HCQ for COVID-19: real-time analysis of all 418 studies

HCQ for COVID-19: real-time meta analysis of 345 studies

Covid Analysis (Preprint) (meta analysis)

• Meta analysis using the most serious outcome reported shows 63% [53‑70%] improvement for the 38 early treatment studies. Results are similar after exclusion based sensitivity analysis and after restriction to peer-reviewed studies. The 11 RCTs show 39% [8‑59%] improvement, and the 15 mortality results shows 72% [57‑81%] lower mortality.

• 21 early treatment studies show statistically significant improvements in isolation (15 for the most serious outcome).

• Late treatment is less successful, with only 67% of the 232 studies reporting a positive effect. Very late stage treatment is not effective and may be harmful, especially when using excessive dosages.

• 78% of Randomized Controlled Trials (RCTs) for early, PrEP, or PEP treatment report positive effects, the probability of results as good or better for an ineffective treatment is 0.0053.

• There is evidence of bias towards publishing negative results. 76% of prospective studies report positive effects, compared to 71% of retrospective studies. Studies from North America are 2.6 times more likely to report negative results than studies from the rest of the world combined, p = 0.0000000245.

• Negative meta analyses of HCQ generally choose a subset of trials, focusing on late treatment, especially trials with very late treatment and excessive dosages.

• While many treatments have some level of efficacy, they do not replace vaccines and other measures to avoid infection. Only 5% of HCQ studies show zero events in the treatment arm.

Multiple treatments are typically used in combination, which may be significantly more effective.

• No treatment, vaccine, or intervention is 100% available and effective for all variants. All practical, effective, and safe means should be used. Denying the efficacy of treatments increases mortality, morbidity, collateral damage, and endemic risk.

• All data to reproduce this paper and the sources are in the appendix. See [Ladapo, Prodromos, Risch, Risch (B)] for other meta analyses showing efficacy when HCQ is used early.

Total	345 studies	5,457 authors	458,509 patients
Positive effects	249 studies	3,844 authors	328,863 patients

Early treatment	63% improvement	RR 0.37 [0.30-0.47]
Late treatment	19% improvement	RR 0.81 [0.76-0.86]

Clinical-Epidemiology Aspect of Inpatients With Moderate or Severe COVID-19 in a Brazilian Macroregion: Disease and Countermeasures

Silva et al., Frontiers in Cellular and Infection Microbiology, doi:10.3389/fcimb.2022.899702

Retrospective 395 hospitalized patients in Brazil, showing higher mortality with HCQ treatment, without statistical significance.

risk of death, 46.1% higher, RR 1.46, p = 0.21, treatment 21, control 374, adjusted, OR converted to RR, multivariable, control prevalance approximated with overall prevalence.

Silva et al., 5/20/2022, retrospective, Brazil, South America, peer-reviewed, mean age 58.4, 28 authors, study period 25 March, 2020 - 21 October, 2020.

Frequentist and Bayesian analysis methods for case series data and application to early outpatient COVID-19 treatment case series of high risk patients

Gkioulekas et al., Authorea, Inc., doi:10.22541/au.164745391.17821933/v2 (Preprint)

Hybrid statistical framework for evaluating treatment protocols. COVID-19 treatment protocols often use risk stratification, multiple treatments, and customization based on the disease stage and the patient. Authors find strong evidence for the efficacy of the early outpatient treatment protocols considered.

Gkioulekas et al., 5/16/2022, retrospective, preprint, 3 authors.

Use of combined treatment of 3rd-generation cephalosporin, azithromycin and antiviral agents on moderate SARs-CoV-2 patients in South Korea: A retrospective cohort study

Hong et al., PLOS ONE, doi:10.1371/journal.pone.0267645

Retrospective 25 hospitalized patients treated with cephalosporin, azithromycin, and HCQ, and 217 SOC patients in South Korea, reporting no significant differences. 5 patients receiving lopinavir/ritonavir and HCQ >5 days were excluded for unknown reasons. HCQ was typically initiated based on progression or side effects from another treatment. Conflicting results are reported. Table 2 indicates 15 CA/HCQ patients after matching, while Table S2 shows 25, and the Table 3 count is blank. S2 appears to incorrectly show before matching results, and the after matching results are missing in Table 3. 200mg HCQ bid.

recovery time, 24.9% lower, HR 0.75, p = 0.45, treatment 15, control 15, propensity score matching.

hospitalization time, 12.7% higher, HR 1.13, p = 0.75, treatment 15, control 15, propensity score matching.

viral clearance time, 0.5% lower, HR 1.00, p = 0.99, treatment 15, control 15, propensity score matching.

Hong et al., 5/4/2022, retrospective, South Korea, Asia, peer-reviewed, 11 authors, study period 28 February, 2020 - 28 April, 2020.

Enhanced In Vitro Antiviral Activity of Hydroxychloroquine Ionic Liquids against SARS-CoV-2

Faísca et al., Pharmaceutics, doi:10.3390/pharmaceutics14040877 (In Vitro)

In Vitro study showing improved antiviral activity with ionic formulations of HCQ.

Faísca et al., 4/17/2022, peer-reviewed, 6 authors.

In Vitro studies are an important part of preclinical research, however results may be very different in vivo.

Efficacy and Safety of Fixed Combination of Hydroxychloroquine with Azithromycin Versus Hydroxychloroquine and Placebo in Patients with Mild COVID-19: Randomized, double blind, Placebo controlled trial

Roy-García et al., medRxiv, doi:10.1101/2022.04.06.22273531 (Preprint)

Small early terminated RCT in Mexico with 31 HCQ and 31 control patients, showing higher progression with treatment. There were no hospitalizations in the HCQ and control groups. HCQ patients were older, 38 vs. 32. There were no differences in QT segment duration and no cardiovascular complications.

The analysis presented includes data from participants that withdrew consent or received incorrect medication (5 patients for HCQ+AZ, 1 HCQ, 0 control). The HCQ+AZ arm was not blind due to the use of a different pill regimen. Results for the individual components of the progression outcome are not provided.

The dosing regimen is poor. Dosing studies and HCQ trials show that a loading dose and sufficiently high doses are important to reach therapeutic concentrations quickly [Ali, Ragonnet], and that excessive cumulative doses over time are harmful.

With the already late treatment (IQR 4-6 days) and non-weight-specific dosing, it is likely that therapeutic concentrations would not be reached early enough during the viral phase in most patients, and the continued treatment for 10 days suggests harmful tissue concentrations could be reached for some patients.

NCT04964583.

1. Ali et al., Journal of Pharmaceutical Research International, doi:10.9734/jpri/2020/v32i830468, Optimizing the Use of Hydroxychloroquine in the Management of COVID-19 Given Its Pharmacological Profile, https://www.journaljpri.com/index.php/JPRI/article/view/30468.

2. Ragonnet et al., Future Pharmacology, doi:10.3390/futurepharmacol2010007, Drug Repositioning in Intensive Care Patients and Pharmacokinetic Variability: The Illustration of Hydroxychloroquine, https://www.mdpi.com/2673-9879/2/1/7.

risk of progression, 100% higher, RR 2.00, p = 1.00, treatment 2 of 31 (6.5%), control 1 of 31 (3.2%), supplemental oxygen.

risk of progression, 233.3% higher, RR 3.33, p = 0.06, treatment 10 of 31 (32.3%), control 3 of 31 (9.7%), pneumonia.

risk of progression, 225.0% higher, RR 3.25, p = 0.02, treatment 13 of 31 (41.9%), control 4 of 31 (12.9%), oxygen saturation less than 90%, dyspnea, or pneumonia.

Roy-García et al., 4/16/2022, Double Blind Randomized Controlled Trial, Mexico, North America, preprint, 11 authors, average treatment delay 5.0 days, dosage 200mg bid days 1-10, trial NCT04964583.

Antiviral Used among Non-Severe COVID-19 Cases in Relation to Time till Viral Clearance: A Retrospective Cohort Study

Hafez et al., Antibiotics, doi:10.3390/antibiotics11040498

Retrospective hospitalized patients in the United Arab Emirates, showing no significant difference in viral clearance with different combinations of HCQ, AZ, favipiravir, and lopinavir/ritonavir.

viral clearance time, 12.3% lower, HR 0.88, p = 0.59, treatment 40, control 1,446, Cox proportional hazards.

viral clearance time, 58.7% lower, HR 0.41, p = 0.09, treatment 4, control 1,446, HCQ + favipiravir + lopinavir/ritonavir, Cox proportional hazards.

Hafez et al., 4/8/2022, retrospective, United Arab Emirates, Middle East, peer-reviewed, 6 authors.

Effect of chronic hydroxychloroquine use on COVID-19 risk in patients with rheumatoid arthritis and systemic lupus erythematosus: a multicenter retrospective cohort

Walbi et al., Journal of International Medical Research, doi:10.1177/03000605221090363

Retrospective RA/SLE patients in Saudi Arabia. Numbers in this paper are contradictory. Figure 1 and the introduction to the results indicate 304 HCQ users, while Table 1 and later in the results shows 207 (arms switched). The subsequent text reporting the ICU results (2 non-HCQ-users, zero HCQ users) suggests that the labels are switched in Figure 2, or possibly just specific results.

Excluded in meta analysis: unresolved data inconsistency.

Walbi et al., 4/6/2022, retrospective, Saudi Arabia, Middle East, peer-reviewed, 16 authors, study period March 2020 - February 2021.

Antiviral Activity of Repurposing Ivermectin against a Panel of 30 Clinical SARS-CoV-2 Strains Belonging to 14 Variants

Delandre et al., Pharmaceuticals, doi:10.3390/ph15040445 (In Vitro)

In Vitro study with 30 COVID-19 strains from 14 variants, showing stronger efficacy with ivermectin compared to CQ and remdesivir, and relatively homogeneous efficacy with ivermectin regardless of strain/variant, in contrast to results for CQ and remdesivir.

CQ showed better efficacy for omicron compared to most other variants.

Delandre et al., 4/2/2022, peer-reviewed, 12 authors.

In Vitro studies are an important part of preclinical research, however results may be very different in vivo.

Hydroxychloroquine versus placebo in the treatment of non-hospitalised patients with COVID-19 (COPE – Coalition V): A double-blind, multicentre, randomised, controlled trial

Avezum et al., The Lancet Regional Health - Americas, doi:10.1016/j.lana.2022.100243

Authors have not responded to a request for the data.

Outpatient RCT with 687 HCQ and 682 control patients in Brazil, showing lower hospitalization with treatment, not reaching statistical significance. Higher efficacy was seen with treatment <4 days from onset, RR 0.61. The associated meta analysis includes mostly late treatment studies, for example in [Schwartz] the median delay from onset was 7 days. [Omrani] is missing. The values for [Johnston] are incorrect - the study shows 4 hospitalizations in the control arm - RR for this study should be 0.58 instead of 0.78. NCT04466540.

1. Johnston et al., EClinicalMedicine, doi:10.1016/j.eclinm.2021.100773 (preprint 12/9), Hydroxychloroquine with or Without Azithromycin for Treatment of Early SARS-CoV-2 Infection Among High-Risk Outpatient Adults: A Randomized Clinical Trial, https://www.thelancet.com/journals../PIIS2589-5370(21)00053-5/fulltext.

2. Omrani et al., EClinicalMedicine, doi:10.1016/j.eclinm.2020.100645, Randomized double-blinded placebo-controlled trial of hydroxychloroquine with or without azithromycin for virologic cure of non-severe Covid-19, https://www.sciencedirect.com/science/article/pii/S2589537020303898.

3. Schwartz et al., CMAJ Open, doi:10.9778/cmajo.20210069, Assessing the efficacy and safety of hydroxychloroquine as outpatient treatment of COVID-19: a randomized controlled trial, http://cmajopen.ca/content/9/2/E693.full.

risk of death, 0.7% lower, RR 0.99, p = 1.00, treatment 5 of 687 (0.7%), control 5 of 682 (0.7%), NNT 18741, all-cause death.

risk of death, 56.0% higher, HR 1.56, p = 0.54, treatment 5 of 687 (0.7%), control 5 of 682 (0.7%), adjusted, univariate Firth's penalized likelihood.

risk of mechanical ventilation, 32.4% higher, RR 1.32, p = 0.79, treatment 8 of 687 (1.2%), control 6 of 682 (0.9%).

risk of ICU admission, 16.4% lower, RR 0.84, p = 0.61, treatment 16 of 687 (2.3%), control 19 of 682 (2.8%), NNT 219.

risk of hospitalization, 23.5% lower, RR 0.77, p = 0.18, treatment 44 of 689 (6.4%), control 57 of 683 (8.3%), NNT 51.

risk of hospitalization, 40.0% lower, RR 0.60, p = 0.15, treatment 267, control 265, <4 days.

Avezum et al., 3/31/2022, Double Blind Randomized Controlled Trial, Brazil, South America, peer-reviewed, 40 authors, study period 12 May, 2020 - 7 July, 2021, average treatment delay 4.0 days, dosage 400mg bid day 1, 200mg bid days 2-7, trial NCT04466540.

Screening Large Population Health Databases for Potential COVID-19 Therapeutics: A Pharmacopeia-Wide Association Study (PWAS) of Commonly Prescribed Medications

MacFadden et al., Open Forum Infectious Diseases, doi:10.1093/ofid/ofac156

Retrospective 26,121 cases and 2,369,020 controls ≥65yo in Canada, showing lower cases with chronic use of HCQ.

risk of case, 12.0% lower, OR 0.88, p = 0.01, RR approximated with OR.

MacFadden et al., 3/29/2022, retrospective, Canada, North America, peer-reviewed, 9 authors, study period 15 January, 2020 - 31 December, 2020.

Randomized controlled trial of favipiravir, hydroxychloroquine, and standard care in patients with mild/moderate COVID-19 disease

AlQahtani et al., Scientific Reports, doi:10.1038/s41598-022-08794-w

RCT with 54 favipiravir, 51 HCQ, and 52 SOC hospitalized patients in Bahrain, showing no significant differences. Viral clearance improved with both treatments, but did not reach statistical significance with the small sample size. NCT04387760.

risk of ICU admission, 23.5% lower, RR 0.76, p = 1.00, treatment 3 of 51 (5.9%), control 4 of 52 (7.7%), NNT 55.

risk of no recovery, 4.1% lower, RR 0.96, p = 0.94, treatment 5 of 49 (10.2%), control 5 of 47 (10.6%), NNT 230.

risk of no viral clearance, 47.4% lower, RR 0.53, p = 0.13, treatment 7 of 38 (18.4%), control 14 of 40 (35.0%), NNT 6.0.

AlQahtani et al., 3/23/2022, Randomized Controlled Trial, Bahrain, Middle East, peer-reviewed, 13 authors, study period August 2020 - March 2021, trial NCT04387760.

Frequency and Severity of COVID-19 in Patients with Various Rheumatic Diseases Treated Regularly with Colchicine or Hydroxychloroquine

Oztas et al., Journal of Medical Virology, doi:10.1002/jmv.27731

Retrospective 317 HCQ users and 333 household contacts, showing higher risk with HCQ.

Authors do not adjust for the very different baseline risk for systemic autoimmune disease patients. Other research shows that the risk of COVID-19 for systemic autoimmune disease patients is much higher overall, Ferri et al. show OR 4.42, p<0.001 [Ferri].

1. Ferri at al., Clinical Rheumatology, doi:0.1007/s10067-020-05334-7, COVID-19 and rheumatic autoimmune systemic diseases: report of a large Italian patients series, https://link.springer.com/article/10.1007/s10067-020-05334-7.

risk of hospitalization, 215.1% higher, RR 3.15, p = 0.36, treatment 3 of 317 (0.9%), control 1 of 333 (0.3%).

risk of symptomatic case, 40.1% higher, RR 1.40, p = 0.44, treatment 16 of 317 (5.0%), control 12 of 333 (3.6%).

risk of case, 5.0% higher, RR 1.05, p = 0.88, treatment 22 of 317 (6.9%), control 22 of 333 (6.6%).

Excluded in after exclusion results of meta analysis: not adjusting for the different baseline risk of systemic autoimmune patients, excessive unadjusted differences between groups.

Oztas et al., 3/21/2022, retrospective, Turkey, Europe, peer-reviewed, 15 authors.

Drug Repositioning in Intensive Care Patients and Pharmacokinetic Variability: The Illustration of Hydroxychloroquine

Ragonnet et al., Future Pharmacology, doi:10.3390/futurepharmacol2010007 (Dosing)

Comparison of two HCQ dosing regimens, showing high inter-individual variability of HCQ concentrations (as in [Ruiz]), and significantly better plasma concentrations for the dosing regimen including a loading dose.

1. Ruiz et al., International Journal of Antimicrobial Agents, doi:10.1016/j.ijantimicag.2020.106247, Hydroxychloroquine lung pharmacokinetics in critically ill patients infected with COVID-19, https://www.sciencedirect.com/science/article/pii/S0924857920304672.

Ragonnet et al., 3/19/2022, peer-reviewed, 9 authors.

Factors predicting in-hospital all-cause mortality in COVID 19 patients at the Laquintinie Hospital Douala, Cameroon

Ebongue et al., Travel Medicine and Infectious Disease, doi:10.1016/j.tmaid.2022.102292

Retrospective 580 hospitalized COVID+ patients in Cameroon, showing lower mortality with HCQ+AZ treatment.

risk of death, 43.0% lower, HR 0.57, p = 0.04, treatment 93 of 522 (17.8%), control 36 of 58 (62.1%), NNT 2.3, adjusted, multivariable.

Ebongue et al., 3/18/2022, retrospective, Cameroon, Africa, peer-reviewed, 27 authors, this trial uses multiple treatments in the treatment arm (combined with AZ) - results of individual treatments may vary.

Comparison of Favipiravir to Hydroxychloroquine Plus Azithromycin in the Treatment of Patients with Non-critical COVID-19: A Single-center, Retrospective, Propensity Score-matched Study

Uyaroğlu et al., Acta Medica, doi:10.32552/2022.ActaMedica.719

PSM retrospective 260 late stage hospitalized COVID-19 pneumonia patients in Turkey, showing no significant difference between favipiravir and HCQ.

risk of death, 200.0% higher, RR 3.00, p = 1.00, treatment 1 of 42 (2.4%), control 0 of 42 (0.0%), continuity correction due to zero event.

risk of ICU admission, 66.7% lower, RR 0.33, p = 1.00, treatment 0 of 42 (0.0%), control 1 of 42 (2.4%), NNT 42, relative risk is not 0 because of continuity correction due to zero events.

hospitalization time, 9.8% lower, relative time 0.90, p = 0.90, treatment 42, control 42.

Uyaroğlu et al., 3/17/2022, retrospective, propensity score matching, Turkey, Europe, peer-reviewed, 6 authors, study period 20 March, 2020 - 30 September, 2020, this trial compares with another treatment - results may be better when compared to placebo.

Risk factors of death in mechanically ventilated COVID-19 patients: a retrospective multi-center study

Salehi et al., Research Square, doi:10.21203/rs.3.rs-1362678/v1 (Preprint)

Retrospective 125 mechanically ventilated ICU patients in Iran, showing no significant difference with HCQ treatment in unadjusted results.

risk of death, 14.5% higher, RR 1.14, p = 0.44, treatment 53 of 86 (61.6%), control 21 of 39 (53.8%).

Excluded in after exclusion results of meta analysis: unadjusted results with no group details.

Salehi et al., 3/11/2022, retrospective, Iran, Middle East, preprint, mean age 62.0, 11 authors, study period April 2021 - September 2021.

Mortality risk factors in patients with SARS-CoV-2 infection and atrial fibrillation: Data from the SEMI-COVID-19 registry

Azaña Gómez et al., Medicina Clínica, doi:10.1016/j.medcli.2022.01.008

Retrospective 1,816 COVID-19 patients with atrial fibrillation in Spain, showing lower mortality with HCQ treatment.

risk of death, 35.8% lower, RR 0.64, p < 0.001, treatment 500 of 1,378 (36.3%), control 238 of 421 (56.5%), NNT 4.9.

Excluded in after exclusion results of meta analysis: unadjusted results with no group details.

Azaña Gómez et al., 3/10/2022, retrospective, Spain, Europe, peer-reviewed, 10 authors, study period 1 March, 2020 - 1 October, 2020.

Daily tenofovir disoproxil fumarate/emtricitabine and hydroxychloroquine for pre-exposure prophylaxis of COVID-19: a double-blind placebo controlled randomized trial in healthcare workers

Del Amo, J., medRxiv, doi:10.1101/2022.03.02.22271710 (Preprint)

PrEP RCT with 231 HCQ, 220 TDF/FTC+HCQ, 233 TDF/FTC, and 223 placebo healthcare workers in Spain, Bolivia, and Venezuela, showing lower risk of symptomatic COVID-19 in all treatment arms, without statistical significance. Only 907 of the planned 4,000 participants were recruited. EPICOS. NCT04334928. EudraCT number 2020-001385-11.

risk of symptomatic case, 51.0% lower, RR 0.49, p = 0.79, treatment 3 of 231 (1.3%), control 5 of 223 (2.2%), NNT 106, HCQ, Kaplan–Meier.

risk of symptomatic case, 61.0% lower, RR 0.39, p = 0.72, treatment 3 of 220 (1.4%), control 5 of 223 (2.2%), TDF+HCQ, Kaplan–Meier.

risk of case, 27.0% lower, RR 0.73, p = 0.31, treatment 21 of 231 (9.1%), control 23 of 223 (10.3%), HCQ, Kaplan–Meier.

risk of case, 49.0% lower, RR 0.51, p = 0.09, treatment 13 of 220 (5.9%), control 23 of 223 (10.3%), NNT 23, TDF+HCQ, Kaplan–Meier.

Del Amo et al., 3/4/2022, Double Blind Randomized Controlled Trial, placebo-controlled, multiple countries, multiple regions, preprint, 1 author, study period April 2020 - May 2021, dosage 200mg daily, trial NCT04334928.

Hydroxychloroquine (HCQ) treatment for hospitalized patients with COVID- 19.

Tsanovska et al., Infectious Disorders - Drug Targets, doi:10.2174/1871526522666220303121209

PSM prospective study of 260 COVID-19 patients in Bulgaria, showing lower mortality, ventilation, and ICU admission with HCQ treatment.

risk of death, 57.9% lower, RR 0.42, p = 0.03, treatment 8 of 70 (11.4%), control 19 of 70 (27.1%), NNT 6.4, propensity score matching.

risk of mechanical ventilation, 73.9% lower, RR 0.26, p < 0.001, treatment 6 of 70 (8.6%), control 23 of 70 (32.9%), NNT 4.1, propensity score matching.

risk of ICU admission, 70.4% lower, RR 0.30, p < 0.001, treatment 8 of 70 (11.4%), control 27 of 70 (38.6%), NNT 3.7, propensity score matching.

Tsanovska et al., 3/3/2022, prospective, Bulgaria, Europe, peer-reviewed, 8 authors, study period 6 November, 2020 - 28 December, 2020.

Mortality and associated risk factors in patients hospitalized due to COVID-19 in a Peruvian reference hospital

Soto et al., PLOS ONE, doi:10.1371/journal.pone.0264789

Retrospective 1,418 very late stage (46% mortality) patients in Peru, showing no significant difference with HCQ. There is strong confounding by indication, for example 48% of patients with baseline SpO₂ <70% were treated compared with 22% for SpO₂ >95%. There may also be significant confounding by time with SOC changing substantially over the first few months of the pandemic.

risk of death, 6.0% higher, HR 1.06, p = 0.46, treatment 292 of 590 (49.5%), control 362 of 828 (43.7%), Cox proportional hazards.

Excluded in after exclusion results of meta analysis: unadjusted results with no group details, substantial unadjusted confounding by indication likely, substantial confounding by time possible due to significant changes in SOC and treatment propensity near the start of the pandemic.

Soto et al., 3/2/2022, retrospective, Peru, South America, peer-reviewed, median age 58.0, 10 authors, study period April 2020 - August 2020, dosage not specified.

Assessment of Recovery Time, Worsening and Death, among COVID-19 inpatients and outpatients, under treatment with Hydroxychloroquine or Chloroquine plus Azithromycin Combination in Burkina Faso

Rouamba et al., International Journal of Infectious Diseases, doi:10.1016/j.ijid.2022.02.034

Retrospective 863 COVID-19 patients in Burkina Faso, showing lower mortality, lower progression for outpatients, and faster viral clearance with HCQ/CQ treatment. Only the lower mortality was statistically significant. NCT04445441.

risk of death, 80.0% lower, HR 0.20, p < 0.001, treatment 20 of 336 (6.0%), control 24 of 73 (32.9%), NNT 3.7, adjusted, inpatients, multivariable, Cox proportional hazards.

risk of progression, 20.0% lower, HR 0.80, p = 0.43, treatment 75 of 745 (10.1%), control 19 of 118 (16.1%), adjusted, all patients, multivariable, Cox proportional hazards.

risk of progression, 73.0% lower, HR 0.27, p = 0.05, treatment 23 of 399 (5.8%), control 4 of 33 (12.1%), adjusted, outpatients, multivariable, Cox proportional hazards, early treatment result.

risk of progression, 7.0% higher, HR 1.07, p = 0.83, treatment 52 of 347 (15.0%), control 15 of 85 (17.6%), adjusted, inpatients, multivariable, Cox proportional hazards.

time to viral clearance, 30.6% lower, HR 0.69, p = 0.26, treatment 746, control 118, adjusted, all patients, propensity score matching, multivariable, Cox proportional hazards, primary outcome.

time to viral clearance, 13.0% lower, HR 0.87, p = 0.29, treatment 746, control 118, adjusted, all patients, without PSM, multivariable, Cox proportional hazards, primary outcome.

time to viral clearance, 21.3% lower, HR 0.79, p = 0.37, treatment 399, control 33, adjusted, outpatients, multivariable, Cox proportional hazards, primary outcome, early treatment result.

time to viral clearance, 13.8% lower, HR 0.86, p = 0.37, treatment 345, control 86, adjusted, inpatients, multivariable, Cox proportional hazards, primary outcome.

Rouamba et al., 2/26/2022, retrospective, Burkina Faso, Africa, peer-reviewed, mean age 42.2, 17 authors, study period 9 March, 2020 - 31 October, 2020, dosage 200mg tid days 1-10, HCQ 200mg tid daily or CQ 250mg bid daily, trial NCT04445441.

Identification of Risk Factors for COVID‐19 Hospitalization in Patients with Anti‐Rheumatic Drugs: Results from a Multicenter Nested Case Control Study

Opdam et al., Clinical Pharmacology & Therapeutics, doi:10.1002/cpt.2551

Retrospective 81 cases and 396 controls among rheumatic disease patients in the Netherlands, showing lower risk of hospitalization with HCQ prophylaxis, without statistical significance.

risk of hospitalization, 45.0% lower, OR 0.55, p = 0.18, treatment 8 of 81 (9.9%) cases, 59 of 396 (14.9%) controls, NNT 17, case control OR.

Opdam et al., 2/23/2022, retrospective, Netherlands, Europe, peer-reviewed, 9 authors.

Multi-institutional Analysis of 505 COVID-19 Patients Supported with ECMO: Predictors of Survival

Hall et al., The Annals of Thoracic Surgery, doi:10.1016/j.athoracsur.2022.01.043

Retrospective 505 ECMO patients showing no significant difference in mortality in unadjusted results.

risk of death, 11.2% lower, RR 0.89, p = 0.31, treatment 31 of 56 (55.4%), control 280 of 449 (62.4%), NNT 14.

Excluded in after exclusion results of meta analysis: unadjusted results with no group details.

Hall et al., 2/18/2022, retrospective, USA, North America, peer-reviewed, 15 authors.

Characteristics associated with poor COVID-19 outcomes in individuals with systemic lupus erythematosus: data from the COVID-19 Global Rheumatology Alliance

Ugarte-Gil et al., Annals of the Rheumatic Diseases, doi:10.1136/annrheumdis-2021-221636

Retrospective 1,606 SLE patients showing lower risk of severe COVID-19 outcomes with HCQ/CQ use.

risk of severe case, 44.4% lower, OR 0.56, p = 0.007, treatment 665, control 230, adjusted, HCQ/CQ only vs. no SLE medication, multivariable, RR approximated with OR.

Ugarte-Gil et al., 2/16/2022, retrospective, multiple countries, multiple regions, peer-reviewed, 58 authors.

Factors associated with hospital admission and adverse outcome for COVID-19: role of social factors and medical care

Beaumont et al., Infectious Diseases Now, doi:10.1016/j.idnow.2022.02.001

Retrospective 296 hospitalized patients in France, showing no significant difference with HCQ treatment.

risk of death/intubation, 14.1% lower, HR 0.86, p = 0.55, treatment 7 of 38 (18.4%), control 88 of 258 (34.1%), NNT 6.4, adjusted, OR converted to RR, Cox proportional hazards.

Beaumont et al., 2/13/2022, retrospective, France, Europe, peer-reviewed, 22 authors, average treatment delay 6.0 days.

Clinical Characteristics and Treatment Outcomes of Mild to Moderate Covid-19 Patients in Saudi Arabia: A Single Centre Study

Albanghali et al., Journal of Infection and Public Health, doi:10.1016/j.jiph.2022.02.001

Retrospective 811 hospitalized COVID+ patients in Saudi Arabia, showing higher mortality with HCQ treatment in unadjusted results subject to confounding by indication.

risk of death, 34.6% higher, RR 1.35, p = 0.46, treatment 20 of 466 (4.3%), control 11 of 345 (3.2%).

Excluded in after exclusion results of meta analysis: unadjusted results with no group details, substantial unadjusted confounding by indication likely.

Albanghali et al., 2/3/2022, retrospective, Saudi Arabia, Middle East, peer-reviewed, 8 authors.

Hydroxychloroquine shortened hospital stay and reduced intensive care unit admissions in hospitalized COVID-19 patients

Omma et al., The Journal of Infection in Developing Countries, doi:10.3855/jidc.14933

Retrospective 393 hospitalized COVID-19 patients in Turkey, showing lower ICU admission and shorter hospitalization time with HCQ. There was no significant difference for mortality. Severity was higher in the HCQ group with greater baseline ventilation, high flow oxygen, fever, and dyspnea.

risk of death, 28.2% lower, RR 0.72, p = 0.30, treatment 17 of 213 (8.0%), control 20 of 180 (11.1%), NNT 32.

risk of ICU admission, 50.2% lower, RR 0.50, p = 0.004, treatment 23 of 213 (10.8%), control 39 of 180 (21.7%), NNT 9.2.

hospitalization time, 16.7% lower, relative time 0.83, p = 0.007, treatment 213, control 180.

Omma et al., 1/31/2022, retrospective, Turkey, Europe, peer-reviewed, 11 authors, study period 1 April, 2020 - 31 December, 2020.

Systematic review and meta-analysis of randomized trials of hydroxychloroquine for the prevention of COVID-19

Garcia-Albeniz et al., medRxiv, doi:10.1101/2020.09.29.20203869 (Preprint) (meta analysis)

Systematic review and meta-analysis of HCQ prophylaxis RCTs showing a statistically significant reduction in cases for pre-exposure prophylaxis.

For PEP trials there were very long treatment delays - in one trial about a third of participants were enrolled 4 days after exposure with an additional shipping delay of ~46 hours on average, and in another trial participants were enrolled up to 7 days after exposure, with an unknown additional delay before treatment, and results suggesting that exposure detection was delayed.

risk of case, 28.0% lower, RR 0.72, p = 0.004, PrEP.

risk of case, 9.0% lower, RR 0.91, p = 0.46, PEP.

Garcia-Albeniz et al., 1/25/2022, preprint, 5 authors.

COVID-19 outcomes in patients with antiphospholipid syndrome: a retrospective cohort study

Erden et al., Bratislava Medical Journal, doi:10.4149/BLL_2022_018

Retrospective 9 COVID-19 patients with antiphospholipid syndrome in Turkey, showing no significant differences based on existing HCQ treatment.

risk of death, 150.0% higher, RR 2.50, p = 1.00, treatment 1 of 6 (16.7%), control 0 of 3 (0.0%), continuity correction due to zero event.

risk of hospitalization, 75.0% lower, RR 0.25, p = 0.23, treatment 1 of 6 (16.7%), control 2 of 3 (66.7%), NNT 2.0.

Excluded in after exclusion results of meta analysis: unadjusted results with no group details.

Erden et al., 1/23/2022, retrospective, Turkey, Europe, peer-reviewed, 11 authors.

Use of glucocorticoids megadoses in SARS-CoV-2 infection in a spanish registry: SEMI-COVID-19

Lavilla Olleros et al., PLOS ONE, doi:10.1371/journal.pone.0261711

Retrospective 14,921 hospitalized patients in Spain, showing lower mortality with HCQ treatment.

risk of death, 36.2% lower, RR 0.64, p < 0.001, treatment 2,285 of 12,772 (17.9%), control 774 of 2,149 (36.0%), NNT 5.5, adjusted, OR converted to RR, multivariable.

Lavilla Olleros et al., 1/21/2022, retrospective, Spain, Europe, peer-reviewed, 22 authors.

Negative Nasopharyngeal SARS-CoV-2 PCR Conversion in Response to Different Therapeutic Interventions

Alwafi et al., Cureus, doi:10.7759/cureus.21442

Retrospective 93 hospitalized patients in Saudi Arabia, 45 treated with CQ/HCQ, showing no significant difference in viral clearance. More patients treated with CQ/HCQ had severe cases at baseline (20% vs. 2%).

risk of no viral clearance, 14.7% lower, RR 0.85, p = 0.65, treatment 12 of 45 (26.7%), control 15 of 48 (31.2%), NNT 22, day 5, primary outcome.

risk of no viral clearance, 25.3% lower, RR 0.75, p = 0.60, treatment 7 of 45 (15.6%), control 10 of 48 (20.8%), NNT 19, day 12.

Excluded in after exclusion results of meta analysis: excessive unadjusted differences between groups.

Alwafi et al., 1/20/2022, retrospective, Saudi Arabia, Middle East, peer-reviewed, 6 authors, study period 7 March, 2020 - 15 April, 2020.

Low Rates of Hospitalization and Death in 4,376 COVID-19 Patients Given Early Ambulatory Medical and Supportive Care. A Case Series and Observational Study.

Tyson et al., Preprint (Preprint)

Retrospective 4,376 patients with mild/moderate COVID-19 in the USA treated with multiple medications including HCQ/ivermectin, favipiravir, vitamin C, D, quercetin, zinc, mAbs, budesonide, dexamethasone, prednisone, and colchicine (exact treatments specific to each patient), showing significantly lower hospitalization and mortality compared to the surrounding community.

risk of death, 99.8% lower, RR 0.002, p < 0.001, treatment 0 of 3,962 (0.0%), control 471 of 20,921 (2.3%), NNT 44, relative risk is not 0 because of continuity correction due to zero events, All AVUC mild patients vs. Imperial County (corrected).

risk of hospitalization, 99.8% lower, RR 0.002, p < 0.001, treatment 2 of 3,962 (0.1%), control 4,343 of 20,921 (20.8%), NNT 4.8, All AVUC mild patients vs. Imperial County (corrected).

risk of death, 97.0% lower, RR 0.03, p < 0.001, treatment 3 of 4,375 (0.1%), control 471 of 20,921 (2.3%), NNT 46, All AVUC patients vs. Imperial County (corrected).

risk of hospitalization, 99.0% lower, RR 0.010, p < 0.001, treatment 9 of 4,375 (0.2%), control 4,343 of 20,921 (20.8%), NNT 4.9, All AVUC patients vs. Imperial County (corrected).

Tyson et al., 1/13/2022, retrospective, USA, North America, preprint, 13 authors.

Prediction of mortality in hospitalized Egyptian patients with Coronavirus disease-2019: A multicenter retrospective study

AbdelGhaffar et al., PLOS ONE, doi:10.1371/journal.pone.0262348

Retrospective 3,712 hospitalized patients in Egypt, showing lower mortality with HCQ treatment in unadjusted results. According to the official treatment protocol, HCQ was recommended with higher risk and/or more serious cases.

risk of death, 99.9% lower, RR 0.001, p < 0.001, treatment 0 of 238 (0.0%), control 900 of 3,474 (25.9%), NNT 3.9, relative risk is not 0 because of continuity correction due to zero events.

AbdelGhaffar et al., 1/11/2022, retrospective, Egypt, Africa, peer-reviewed, 17 authors, study period April 2020 - July 2020.

Hydroxychloroquine pre-exposure prophylaxis provides no protection against COVID-19 among health care workers: a cross-sectional study in a tertiary care hospital in North India

Juneja et al., Journal of Basic and Clinical Physiology and Pharmacology, doi:10.1515/jbcpp-2021-0221

Retrospective 2,200 healthcare workers in India, 996 taking HCQ prophylaxis, showing no significant differences. There were large differences in the occupation of participants and therefore exposure, and the authors make no adjustments.

risk of severe case, 141.8% higher, RR 2.42, p = 0.59, treatment 2 of 996 (0.2%), control 1 of 1,204 (0.1%).

risk of case, 6.4% higher, RR 1.06, p = 0.67, treatment 103 of 996 (10.3%), control 117 of 1,204 (9.7%).

Excluded in after exclusion results of meta analysis: excessive unadjusted differences between groups.

Juneja et al., 1/7/2022, retrospective, India, South Asia, peer-reviewed, 9 authors, study period 2 April, 2020 - 3 September, 2020.

Safety and Tolerability of Hydroxychloroquine in healthcare workers and first responders for the prevention of COVID-19: WHIP COVID-19 Study

McKinnon et al., International Journal of Infectious Diseases, doi:10.1016/j.ijid.2021.12.343

HCQ PrEP RCT with 201 weekly HCQ patients, 197 daily HCQ patients, and 200 control patients, concluding the prophylaxis is safe. There were no grade 3 or 4 AEs, SAEs, ER visits, or hospitalizations. There was only 4 confirmed cases, 2 in the placebo arm and one in each HCQ arm.

HCQ 400mg weekly or HCQ 200mg daily after a loading dose of 400mg on day 1. WHIP COVID-19. NCT04341441.

risk of symptomatic case, 2.5% lower, RR 0.98, p = 1.00, treatment 2 of 365 (0.5%), control 1 of 178 (0.6%), NNT 7219, daily and weekly HCQ combined.

risk of symptomatic case, no change, RR 1.00, p = 1.00, treatment 1 of 178 (0.6%), control 1 of 178 (0.6%), daily HCQ.

risk of symptomatic case, 4.8% lower, RR 0.95, p = 1.00, treatment 1 of 187 (0.5%), control 1 of 178 (0.6%), NNT 3698, weekly HCQ.

risk of symptomatic case, 53.3% lower, RR 0.47, p = 1.00, treatment 0 of 25 (0.0%), control 1 of 178 (0.6%), NNT 178, relative risk is not 0 because of continuity correction due to zero events, AD patients.

risk of case, 51.2% lower, RR 0.49, p = 0.60, treatment 2 of 365 (0.5%), control 2 of 178 (1.1%), NNT 174, daily and weekly HCQ combined.

risk of case, 50.0% lower, RR 0.50, p = 1.00, treatment 1 of 178 (0.6%), control 2 of 178 (1.1%), NNT 178, daily HCQ.

risk of case, 52.4% lower, RR 0.48, p = 0.61, treatment 1 of 187 (0.5%), control 2 of 178 (1.1%), NNT 170, weekly HCQ.

risk of case, 69.5% lower, RR 0.30, p = 1.00, treatment 0 of 25 (0.0%), control 2 of 178 (1.1%), NNT 89, relative risk is not 0 because of continuity correction due to zero events, AD patients.

McKinnon et al., 12/23/2021, Double Blind Randomized Controlled Trial, USA, North America, peer-reviewed, 10 authors, trial NCT04341441.

Hydroxychloroquine as pre-exposure prophylaxis against COVID-19 infection among healthcare workers: a prospective cohort study

Rao et al., Expert Review of Anti-infective Therapy, doi:10.1080/14787210.2022.2015326

Prospective PrEP study with low risk healthcare workers in India showing RR=0.89 [0.53-1.52]. There were no significant adverse effects. Only mean age and gender distribution are provided for baseline characteristics, no severity information is provided, and no adjustments were made. Authors analyze HCQ use for <8 vs. ≥8 weeks, noting a lack of statistical significance, but not providing the results.

risk of case, 11.0% lower, RR 0.89, p = 0.68, treatment 16 of 273 (5.9%), control 67 of 1,021 (6.6%), NNT 143.

Excluded in after exclusion results of meta analysis: unadjusted results with minimal group details.

Rao et al., 12/4/2021, prospective, India, South Asia, peer-reviewed, 8 authors.

Outcomes associated with Hydroxychloroquine and Ivermectin in hospitalized patients with COVID-19: a single-center experience

Ferreira et al., Revista da Associação Médica Brasileira, doi:10.1590/1806-9282.20210661

Retrospective 230 hospitalized patients in Brazil showing higher mortality with HCQ treatment. Authors note that the treatments were more likely to be offered to sicker patients. Authors indicate that they do not know when medication was started, which in some cases could have been after ICU admission or intubation. Dosage is unknown.

risk of death, 151.5% higher, RR 2.51, p = 0.03, treatment 17 of 111 (15.3%), control 11 of 81 (13.6%), OR converted to RR, multivariate.

risk of death/intubation, 45.9% higher, RR 1.46, p = 0.23, treatment 30 of 111 (27.0%), control 15 of 81 (18.5%).

risk of death/intubation/ICU, 61.3% higher, RR 1.61, p = 0.04, treatment 42 of 111 (37.8%), control 19 of 81 (23.5%).

Ferreira et al., 11/26/2021, retrospective, Brazil, South America, peer-reviewed, 5 authors, study period 12 March, 2020 - 8 July, 2020, average treatment delay 7.0 days, dosage not specified.

Treatment with hydroxychloroquine vs nitazoxanide in patients with COVID-19: brief report

Calderón et al., PAMJ - Clinical Medicine, doi:10.11604/pamj-cm.2021.7.15.30981

Planned RCT of HCQ vs. HCQ+nitazoxanide which was aborted due to the retracted Surgisphere paper. Authors retrospectively analyze a small set of HCQ vs. nitazoxanide patients (which were protocol deviations in the planned RCT), showing reduced hospitalization time and ICU admission with nitazoxanide.

risk of death, 214.8% higher, RR 3.15, p = 0.38, treatment 5 of 27 (18.5%), control 1 of 17 (5.9%).

risk of mechanical ventilation, 651.9% higher, RR 7.52, p = 0.15, treatment 4 of 27 (14.8%), control 0 of 17 (0.0%), continuity correction due to zero event.

risk of ICU admission, 145.5% higher, RR 2.45, p < 0.001, treatment 16 of 27 (59.3%), control 0 of 17 (0.0%), adjusted.

hospitalization time, 107.4% higher, relative time 2.07, p = 0.006, treatment 27, control 17.

Calderón et al., 11/23/2021, retrospective, Mexico, North America, peer-reviewed, 7 authors, dosage 200mg bid days 1-7.

Factors Affecting the Incidence, Progression, and Severity of COVID-19 in Type 1 Diabetes Mellitus

Ahmed et al., BioMed Research International, doi:10.1155/2021/1676914

Retrospective type 1 diabetes patients in Saudi Arabia showing reduced risk of cases with HCQ prophylaxis.

risk of case, 99.3% lower, OR 0.007, p = 0.08, treatment 0 of 50 (0.0%) cases, 13 of 50 (26.0%) controls, NNT 1.7, case control OR.

Ahmed et al., 11/23/2021, retrospective, Saudi Arabia, Middle East, peer-reviewed, 7 authors.

Ivermectin and Hydroxychloroquine for Chemo-Prophylaxis of COVID-19: A Questionnaire Survey of Perception and Prescribing Practice of Physicians vis-a-vis Outcomes

Samajdar et al., Journal of the Association of Physicians India, 69:11

Physician survey in India with 164 ivermectin prophylaxis, 129 HCQ prophylaxis, and 81 control patients, showing significantly lower COVID-19 cases with treatment. Details of the treatment and control groups and the definition of cases are not provided, and the results are subject to survey bias. Authors also report on community prophylaxis but present only combined ivermectin/HCQ results.

risk of case, 74.5% lower, RR 0.25, p < 0.001, treatment 12 of 129 (9.3%), control 29 of 81 (35.8%), NNT 3.8, OR converted to RR, physician survey.

risk of case, 48.6% lower, RR 0.51, p = 0.03, treatment 11 of 109 (10.1%), control 39 of 200 (19.5%), NNT 11, OR converted to RR, combined ivermectin or HCQ in community.

Excluded in after exclusion results of meta analysis: minimal details provided, unadjusted results with no group details, results may be significantly affected by survey bias.

Samajdar et al., 11/17/2021, retrospective, India, South Asia, peer-reviewed, 9 authors, study period 1 September, 2020 - 31 December, 2020, dosage not specified.

Association Between Androgen Deprivation Therapy and Mortality Among Patients With Prostate Cancer and COVID-19

Schmidt et al., JAMA Network Open, doi:10.1001/jamanetworkopen.2021.34330

Retrospective 1,106 prostate cancer patients, showing higher mortality with HCQ treatment.

risk of death, 333.0% higher, OR 4.33, p < 0.001, treatment 70, control 407, adjusted, propensity score matching, multivariable, RR approximated with OR, excluded in exclusion analyses: confounding by indication is likely and adjustments do not consider COVID-19 severity at baseline.

risk of severe case, 613.0% higher, OR 7.13, p < 0.001, treatment 70, control 407, adjusted, propensity score matching, multivariable, RR approximated with OR, excluded in exclusion analyses: confounding by indication is likely and adjustments do not consider COVID-19 severity at baseline.

Schmidt et al., 11/12/2021, retrospective, USA, North America, peer-reviewed, 42 authors, study period 17 March, 2020 - 11 February, 2021.

Clinical characteristics and outcomes of COVID-19 patients in a tertiary hospital in Baguio City, Philippines

Cortez et al., Western Pacific Surveillance and Response Journal, doi:10.5365/wpsar.2021.12.4.852

Retrospective 280 hospitalized patients in the Philippines, 25 treated with HCQ, not showing any significant differences in unadjusted results.

risk of death, 15.0% lower, RR 0.85, p = 1.00, treatment 1 of 25 (4.0%), control 12 of 255 (4.7%), NNT 142.

Excluded in after exclusion results of meta analysis: unadjusted results with no group details.

Cortez et al., 11/11/2021, retrospective, Philippines, Asia, peer-reviewed, 29 authors, study period March 2020 - October 2020.

Evaluation of patients treated by telemedicine in the COVID-19 pandemic by a private clinic in Sao Paulo, Brazil: A non-randomized clinical trial preliminary study

Chechter et al., medRxiv, doi:10.1101/2021.11.05.21265569 (Preprint)

Prospective study of 187 telemedicine patients in Brazil. 74 presenting with moderate symptoms were offered treatment with HCQ+AZ, 12 did not accept HCQ (taking AZ only), forming a control group. There was lower hospitalization and improved recovery with treatment. There appears to be different group sizes in the text and tables without explanation (maybe a typo). RBR-658khm.

risk of hospitalization, 94.7% lower, RR 0.05, p = 0.004, treatment 0 of 60 (0.0%), control 3 of 12 (25.0%), NNT 4.0, relative risk is not 0 because of continuity correction due to zero events.

Excluded in after exclusion results of meta analysis: unadjusted results with no group details.

Chechter et al., 11/5/2021, prospective, Brazil, South America, preprint, 13 authors, dosage 800mg day 1, 400mg days 2-5, this trial uses multiple treatments in the treatment arm (combined with AZ) - results of individual treatments may vary.

Efficacy of the early treatment with tocilizumab-hydroxychloroquine and tocilizumab-remdesivir in severe COVID-19 Patients

Sarhan et al., Journal of Infection and Public Health, doi:10.1016/j.jiph.2021.10.024

Small 108 patient RCT comparing HCQ vs. remdesivir in very late stage treatment. All patients received tocilizumab. There were significant unadjusted baseline differences in ventilation and ICU admission. NCT04779047. REC-H-PhBSU-21011.

risk of death, 25.7% lower, RR 0.74, p = 0.39, treatment 12 of 56 (21.4%), control 15 of 52 (28.8%), NNT 13.

risk of no hospital discharge, 25.7% lower, RR 0.74, p = 0.39, treatment 12 of 56 (21.4%), control 15 of 52 (28.8%), NNT 13.

hospitalization time, 25.0% higher, relative time 1.25, p = 0.06, treatment 56, control 52.

Excluded in after exclusion results of meta analysis: very late stage, >50% on oxygen/ventilation at baseline, significant unadjusted differences between groups.

Sarhan et al., 11/2/2021, Randomized Controlled Trial, Egypt, Africa, peer-reviewed, 8 authors, study period 1 October, 2020 - 10 March, 2021, this trial compares with another treatment - results may be better when compared to placebo, trial NCT04779047.

Hepatic and gastrointestinal disturbances in Egyptian patients infected with coronavirus disease 2019: A multicentre cohort study

Shousha et al., World Journal of Gastroenterology, doi:10.3748/wjg.v27.i40.6951

Retrospective 547 hospitalized COVID+ patients in Egypt, showing no significant differences with CQ/HCQ treatment in unadjusted analysis. Treatments were applied according to patient conditions, demographics, and comorbidities as per the the official guidelines, indicating strong confounding by indication.

risk of death, 11.5% lower, RR 0.88, p = 0.87, treatment 12 of 136 (8.8%), control 41 of 411 (10.0%), NNT 87, unadjusted.

Excluded in meta analysis: confounding by indication, unadjusted results and treatment used selectively per official protocol, unadjusted results with no group details.

Shousha et al., 10/28/2021, retrospective, Egypt, Africa, peer-reviewed, 18 authors, study period 15 April, 2020 - 29 July, 2020.

Treatment for COVID-19—a cohort study from Northern Italy

Guglielmetti et al., Scientific Reports, doi:10.1038/s41598-021-00243-4

Retrospective 600 hospitalized patients in Italy, showing lower mortality with HCQ treatment, without reaching statistical significance (p = 0.1).

risk of death, 28.0% lower, HR 0.72, p = 0.10, treatment 474, control 126, multivariable Cox proportional hazards.

Guglielmetti et al., 10/25/2021, retrospective, Italy, Europe, peer-reviewed, 19 authors, study period 21 February, 2020 - 15 May, 2020.

COVID-19 PrEP HCW HCQ Study

Belmont et al., ClinicalTrials.gov, NCT04354870 (Preprint)

Prospective study of HCQ prophylaxis in the USA, with 56 HCQ patients and 24 control patients, showing no significant differences. NCT04354870

risk of symptomatic case, 78.6% lower, RR 0.21, p = 0.21, treatment 1 of 56 (1.8%), control 2 of 24 (8.3%), NNT 15.

risk of case, 14.3% lower, RR 0.86, p = 1.00, treatment 4 of 56 (7.1%), control 2 of 24 (8.3%), NNT 84.

Belmont et al., 10/6/2021, prospective, USA, North America, preprint, 1 author, trial NCT04354870.

Various Combinations of Favipiravir, Lopinavir-Ritonavir, Darunavir-Ritonavir, High-Dose Oseltamivir, and Hydroxychloroquine for the Treatment of COVID-19: A Randomized Controlled Trial (FIGHT-COVID-19 Study)

Atipornwanich et al., SSRN Electronic Journal, doi:10.2139/ssrn.3936499

RCT 320 patients in Thailand, showing significantly lower progression with HCQ for moderate/severe patients, and faster viral clearance with mild patients (statistically significant for 800mg). There are two sets of results - for moderate/severe patients, and for mild patients. There was no mortality for mild patients. NCT04303299.

risk of death, 56.2% lower, RR 0.44, p = 0.07, treatment 7 of 100 (7.0%), control 16 of 100 (16.0%), NNT 11, moderate/severe, HCQ arms vs. non-HCQ arms.

risk of progression, 54.2% lower, RR 0.46, p = 0.02, treatment 11 of 100 (11.0%), control 24 of 100 (24.0%), NNT 7.7, moderate/severe, HCQ arms vs. non-HCQ arms.

time to viral-, 7.1% lower, relative time 0.93, p = 0.51, treatment mean 10.4 (±6.3) n=50, control mean 11.2 (±5.7) n=50, moderate/severe, oseltamivir arms, primary outcome.

time to viral-, 6.9% lower, relative time 0.93, p = 0.47, treatment mean 9.5 (±5.0) n=50, control mean 10.2 (±4.6) n=50, moderate/severe, favipiravir arms, primary outcome.

risk of progression, 150.0% higher, RR 2.50, p = 1.00, treatment 1 of 60 (1.7%), control 0 of 30 (0.0%), continuity correction due to zero event, mild, early treatment result.

time to viral-, 43.3% lower, relative time 0.57, p = 0.04, treatment mean 8.9 (±6.0) n=30, control mean 15.7 (±16.7) n=30, mild, HCQ 800, primary outcome, early treatment result.

time to viral-, 36.3% lower, relative time 0.64, p = 0.09, treatment mean 10.0 (±6.9) n=30, control mean 15.7 (±16.7) n=30, mild, HCQ 400, primary outcome, early treatment result.

Atipornwanich et al., 10/5/2021, Randomized Controlled Trial, Thailand, South Asia, peer-reviewed, 16 authors, dosage 400mg days 1-14, 800mg/day or 400mg/day, this trial compares with another treatment - results may be better when compared to placebo, this trial uses multiple treatments in the treatment arm (combined with oseltamivir/favipiravir and duranivir/ritonavir for moderate/severe, oseltamivir and duranivir/ritonavir for mild) - results of individual treatments may vary, trial NCT04303299.

A Randomized Controlled Trial of Ivermectin Monotherapy Versus Hydroxychloroquine, Ivermectin, and Azithromycin Combination Therapy in Covid-19 Patients in Nigeria

Babalola et al., Research Square, doi:10.21203/rs.3.rs-950352/v1 (Preprint)

Small RCT with 61 patients in Nigeria, all patients treated with ivermectin, zinc, and vitamin C, showing no significant improvements in recovery with the addition of HCQ+AZ. PACTR202108891693522.

risk of no hospital discharge, 54.5% higher, RR 1.55, p = 0.20, treatment 17 of 30 (56.7%), control 11 of 30 (36.7%), day 7.

risk of no viral clearance, 9.5% lower, RR 0.90, p = 0.78, treatment 19 of 30 (63.3%), control 21 of 30 (70.0%), NNT 15, day 5 mid-recovery.

Babalola et al., 10/1/2021, Single Blind Randomized Controlled Trial, Nigeria, Africa, preprint, 6 authors, this trial uses multiple treatments in the treatment arm (combined with AZ) - results of individual treatments may vary.

Effect of common maintenance drugs on the risk and severity of COVID-19 in elderly patients

Fung et al., PLoS ONE, doi:10.1371/journal.pone.0266922 (preprint 10/1/2021)

Retrospective database analysis of 374,229 patients in the USA, showing no significant difference with HCQ use, however authors do not adjust for the very different baseline risk for systemic autoimmune disease patients. Other research shows that the risk of COVID-19 for systemic autoimmune disease patients is much higher overall, Ferri et al. show OR 4.42, p<0.001 [Ferri].

Authors compare with patients that never used HCQ and with patients that previously used HCQ. The comparison with patients previously using HCQ is more relevant because the matching of patients with systemic autoimmune disease is likely to be better.

1. Ferri at al., Clinical Rheumatology, doi:0.1007/s10067-020-05334-7, COVID-19 and rheumatic autoimmune systemic diseases: report of a large Italian patients series, https://link.springer.com/article/10.1007/s10067-020-05334-7.

risk of death, 13.0% lower, HR 0.87, p = 0.15, vs. past use (better match for systemic autoimmune diseases).

risk of hospitalization, 3.0% lower, HR 0.97, p = 0.63, vs. past use (better match for systemic autoimmune diseases).

risk of case, 9.0% lower, HR 0.91, p = 0.02, vs. past use (better match for systemic autoimmune diseases).

risk of death, 8.0% higher, HR 1.08, p = 0.26, vs. never used.

risk of hospitalization, 6.0% higher, HR 1.06, p = 0.13, vs. never used.

risk of case, 5.0% lower, HR 0.95, p = 0.03, vs. never used.

Excluded in after exclusion results of meta analysis: not fully adjusting for the different baseline risk of systemic autoimmune patients.

Fung et al., 10/1/2021, retrospective, population-based cohort, USA, North America, peer-reviewed, 6 authors.

A retrospective analysis on pharmacological approaches to COVID-19 patients in an Italian hub hospital during the early phase of the pandemic

Menardi et al., PharmAdvances, doi:10.36118/pharmadvances.2021.15

Retrospective 277 hospitalized patients in Italy, showing lower mortality with HCQ treatment, not reaching statistical significance, and subject to confounding by indication.

risk of death, 35.2% lower, RR 0.65, p = 0.12, treatment 32 of 200 (16.0%), control 19 of 77 (24.7%), NNT 12.

Excluded in after exclusion results of meta analysis: excessive unadjusted differences between groups, substantial unadjusted confounding by indication likely.

Menardi et al., 9/30/2021, retrospective, Italy, Europe, peer-reviewed, 10 authors.

Effect of Hydroxychloroquine Use on the Length Of Hospital Stay in Children Diagnosed With Covid 19

Uygen et al., Northern Clinics of Istanbul, doi:10.14744/nci.2021.65471

Retrospective 40 pediatric hospitalized patients, 15 treated with HCQ, showing 7.2 vs. 8.2 days until PCR-, not quite reaching statistical significance.

time to viral-, 12.2% lower, relative time 0.88, p = 0.05, treatment 15, control 25.

Uygen et al., 9/15/2021, retrospective, Turkey, Europe, peer-reviewed, 4 authors.

Clinical Characteristics and Outcome of COVID-19 in Turkish Hematological Malignancy Patients

Çivriz Bozdağ et al., Turk. J. Haematol., doi:10.4274/tjh.galenos.2021.2021.0287

Retrospective 340 patients with hematological malignancy in Turkey, showing higher mortality with HCQ treatment. Confounding by time is likely because more HCQ patients were earlier in time when overall treatment protocols were significantly worse.

risk of death, 399.2% higher, RR 4.99, p = 0.003, treatment 35, control 140.

Excluded in after exclusion results of meta analysis: substantial confounding by time likely due to declining usage over the early stages of the pandemic when overall treatment protocols improved dramatically.

Çivriz Bozdağ et al., 9/15/2021, retrospective, Turkey, Europe, peer-reviewed, 62 authors.

Effectiveness and Safety of Favipiravir Compared to Hydroxychloroquine for Management of Covid-19: A Retrospective Study

Alotaibi et al., International Journal of General Medicine, 2021:14

Retrospective hospitalized patients in Saudi Arabia, showing lower mortality with favipiravir compared to HCQ, not quite reaching statistical significance. Authors do not indicate the factors behind which therapy was chosen. May be subject to significant confounding by indication and confounding by time.

risk of death, 133.5% higher, RR 2.33, p = 0.05, treatment 193, control 244, multivariate.

Alotaibi et al., 9/14/2021, retrospective, Saudi Arabia, Middle East, peer-reviewed, 11 authors, this trial compares with another treatment - results may be better when compared to placebo.

Low dose hydroxychloroquine prophylaxis for COVID-19 - a prospective study

Agarwal et al., medRxiv, doi:10.1101/2021.09.13.21262971 (Preprint)

Small prophylaxis trial with 29 low dose HCQ and 455 control healthcare workers in India, showing no statistically significant differences.

risk of hospitalization, 94.8% lower, RR 0.05, p = 0.61, treatment 0 of 29 (0.0%), control 17 of 455 (3.7%), NNT 27, relative risk is not 0 because of continuity correction due to zero events.

relative severity, 26.9% better, RR 0.73, p = 0.21, treatment 29, control 455.

risk of case, 4.6% higher, RR 1.05, p = 0.81, treatment 6 of 29 (20.7%), control 90 of 455 (19.8%).

Agarwal et al., 9/14/2021, prospective, India, South Asia, preprint, 1 author.

Hydroxychloroquine / azithromycin in COVID-19: The association between time to treatment and case fatality rate

Accinelli et al., Travel Medicine and Infectious Disease, doi:10.1016/j.tmaid.2021.102163

Retrospective 1,265 outpatients in Peru treated with HCQ+AZ showing mortality associated with treatment delay. Mortality was six times lower than the national average.

Accinelli et al., 9/14/2021, peer-reviewed, 6 authors, this trial uses multiple treatments in the treatment arm (combined with AZ) - results of individual treatments may vary.

Assessment of outcomes following implementation of antiviral treatment guidelines for COVID-19 during the first wave in Thailand

Sawanpanyalert et al., Southeast Asian Journal of Tropical Medicine and Public Health, 52:4

Retrospective 744 hospitalized patients in Thailand, showing lower risk of a poor outcome for favipiravir treatment within 4 days of symptom onset. Early treatment with CQ/HCQ and lopinavir/ritonavir or darunavir/ritonavir also showed lower risk, but without statistical significance. Sample sizes for the number of patients treated within 4 days of symptom onset are not provided.

risk of death, ICU, intubation, or high-flow oxygen, 42.0% lower, OR 0.58, p = 0.37, within 4 days of symptom onset, RR approximated with OR.

Sawanpanyalert et al., 9/9/2021, retrospective, Thailand, South Asia, peer-reviewed, 11 authors, dosage varies, this trial uses multiple treatments in the treatment arm (combined with lopinavir/ritonavir or darunavir/ritonavir) - results of individual treatments may vary.

Multidrug-Resistant Infections and Outcome of Critically Ill Patients with Coronavirus Disease 2019: A Single Center Experience

Karruli et al., Microbial Drug Resistance, doi:10.1089/mdr.2020.0489

Retrospective 32 ICU patients, showing no significant difference with HCQ treatment in unadjusted results.

risk of death, 4.8% lower, RR 0.95, p = 1.00, treatment 20 of 28 (71.4%), control 3 of 4 (75.0%), NNT 28.

Excluded in after exclusion results of meta analysis: unadjusted results with no group details.

Karruli et al., 9/1/2021, retrospective, Italy, Europe, peer-reviewed, 13 authors, study period March 2020 - May 2020.

Incidence of COVID-19 Hospitalisation in Patients with Systemic Lupus Erythematosus: A Nationwide Cohort Study from Denmark

Cordtz et al., Journal of Clinical Medicine, doi:10.3390/jcm10173842

Retrospective 2,533 SLE patients in Denmark showing no significant difference in hospitalization risk for COVID-19 cases with HCQ treatment.

risk of hospitalization, 40.0% lower, HR 0.60, p = 0.39, treatment 1,170, control 1,363, adjusted.

Cordtz et al., 8/27/2021, retrospective, population-based cohort, Denmark, Europe, peer-reviewed, 8 authors, study period 1 March, 2020 - 2 February, 2021.

Hydroxychloroquine plus azithromycin early treatment of mild COVID-19 in outpatient setting: a randomized, double-blinded, placebo-controlled clinical trial evaluating viral clearance

Rodrigues et al., International Journal of Antimicrobial Agents, doi:10.1016/j.ijantimicag.2021.106428

RCT 84 low risk patients, 42 treated with HCQ/AZ, showing no significant differences. There was only one hospitalization which was in the treatment arm.

risk of hospitalization, 200.0% higher, RR 3.00, p = 1.00, treatment 1 of 42 (2.4%), control 0 of 42 (0.0%), continuity correction due to zero event.

risk of no viral clearance, 14.4% lower, RR 0.86, p = 0.15, treatment 29 of 36 (80.6%), control 32 of 34 (94.1%), NNT 7.4, PP, day 3.

risk of no viral clearance, 13.1% lower, RR 0.87, p = 0.45, treatment 23 of 36 (63.9%), control 25 of 34 (73.5%), NNT 10, PP, day 6.

risk of no viral clearance, 23.3% lower, RR 0.77, p = 0.47, treatment 13 of 36 (36.1%), control 16 of 34 (47.1%), NNT 9.1, PP, day 9.

risk of no viral clearance, 3.1% lower, RR 0.97, p = 1.00, treatment 31 of 42 (73.8%), control 32 of 42 (76.2%), NNT 42, ITT, day 3.

risk of no viral clearance, no change, RR 1.00, p = 1.00, treatment 25 of 42 (59.5%), control 25 of 42 (59.5%), ITT, day 6.

risk of no viral clearance, 6.2% lower, RR 0.94, p = 1.00, treatment 15 of 42 (35.7%), control 16 of 42 (38.1%), NNT 42, ITT, day 9.

time to viral-, 8.8% lower, relative time 0.91, p = 0.26, treatment 36, control 34, PP.

time to viral-, 1.4% lower, relative time 0.99, p = 0.85, treatment 42, control 42, ITT.

Rodrigues et al., 8/25/2021, Double Blind Randomized Controlled Trial, Brazil, South America, peer-reviewed, 8 authors, average treatment delay 3.8 days, dosage 400mg bid days 1-7, this trial uses multiple treatments in the treatment arm (combined with AZ) - results of individual treatments may vary.

Hydroxychloroquine for pre-exposure prophylaxis of COVID-19 in health care workers: a randomized, multicenter, placebo-controlled trial (HERO-HCQ)

Naggie et al., medRxiv, doi:10.1101/2021.08.19.21262275 (Preprint)

RCT 1,360 healthcare workers in the USA showing OR 0.75 [0.49-1.15] for confirmed or suspected COVID-19 clinical infection by day 30. There were no significant safety issues. Authors note that pooling the results with the COVID PREP study gives OR 0.74 [0.55-1.0] p = 0.046. NCT04334148.

risk of symptomatic case, 23.5% lower, RR 0.76, p = 0.18, treatment 41 of 683 (6.0%), control 53 of 676 (7.8%), NNT 54, OR converted to RR, logistic regression.

risk of symptomatic case, 29.3% lower, RR 0.71, p = 0.18, treatment 41 of 683 (6.0%), control 53 of 676 (7.8%), NNT 54, OR converted to RR, Mantel–Haenszel.

Naggie et al., 8/25/2021, Randomized Controlled Trial, USA, North America, preprint, 22 authors, trial NCT04334148.

A Prospective Longitudinal Study Evaluating The Influence of Immunosuppressives and Other Factors On COVID-19 in Autoimmune Rheumatic Diseases

Patil et al., Research Square, doi:10.21203/rs.3.rs-805748/v1 (Preprint)

Prospective study of 9,212 autoimmune rheumatic disease patients showing lower mortality with HCQ, without reaching statistical significance. Authors incorrectly state "HCQ use did not influence occurrence of COVID-19 (RR = 0.909, CI (0.715,1.154), p = 0.432) or mortality (p = 0.097)" [nature.com]. CFR for the autoimmune rheumatic disease patients was 4.6 times higher than in the general population from the same area.

1. nature.com, https://www.nature.com/articles/d41586-019-00857-9.

risk of death, 65.9% lower, RR 0.34, p = 0.10, treatment 5,266, control 3,946.

risk of case, 9.1% lower, RR 0.91, p = 0.43, treatment 167 of 5,266 (3.2%), control 147 of 3,946 (3.7%), NNT 181, adjusted.

Patil et al., 8/24/2021, prospective, India, South Asia, preprint, 20 authors.

Comparative study between the therapeutic effect of remdesivir versus hydroxychloroquine in COVID-19 hospitalized patients

Eldeen et al., Microbes and Infectious Diseases, doi:10.21608/mid.2021.85877.1177

Small study comparing 25 HCQ and 25 remdesivir hospitalized patients, reporting faster viral clearance with remdesivir. The article proof is missing the results for the HCQ group. Confounding by time is likely - remdesivir patients were after HCQ patients in time, and treatment protocols improved over the period of the study.

Eldeen et al., 8/16/2021, peer-reviewed, 5 authors.

Nebulised Isotonic Hydroxychloroquine Aerosols for Potential Treatment of COVID-19

Tai et al., Pharmaceutics, doi:10.3390/pharmaceutics13081260

Analysis of HCQ solutions suitable for nebulization for COVID-19.

Tai et al., 8/14/2021, peer-reviewed, 8 authors.

Evaluation of the Prophylactic Effect of Hydroxychloroquine on People in Close-Contact with Patients with Covid-19

Shabani et al., Pulmonary Pharmacology & Therapeutics, doi:10.1016/j.pupt.2021.102069

Small PEP trial with 51 HCQ patients, not showing a significant difference in cases. IRCT20130917014693N10.

risk of symptomatic case, 19.0% lower, RR 0.81, p = 1.00, treatment 2 of 51 (3.9%), control 3 of 62 (4.8%), NNT 109, day 7.

risk of case, 6.4% higher, RR 1.06, p = 1.00, treatment 7 of 51 (13.7%), control 8 of 62 (12.9%), day 7, PCR+ and symptomatic.

risk of case, 21.6% higher, RR 1.22, p = 0.78, treatment 7 of 51 (13.7%), control 7 of 62 (11.3%), day 7, PCR+ only.

Shabani et al., 8/10/2021, prospective, Iran, Middle East, peer-reviewed, 16 authors.

Hydroxychloroquine Pre-Exposure Prophylaxis for COVID-19 in Healthcare Workers from India: A Meta-Analysis

Stricker et al., Journal of Infection and Public Health, doi:10.1016/j.jiph.2021.08.001 (meta analysis)

Meta analysis of 11 HCQ PrEP studies in India covering 7,616 healthcare workers, showing significantly lower cases with treatment.

risk of death, 75.0% lower, RR 0.25, p < 0.001, treatment 1,273, control 4,127, >=6 doses.

risk of death, 44.0% lower, RR 0.56, p = 0.004, treatment 3,489, control 4,127, any number of doses.

Stricker et al., 8/5/2021, peer-reviewed, 2 authors.

The Efficacy of Hydroxychloroquine and Azithromycin Combination Therapy on Hospital Mortality in COVID 19 Pneumonia Patients

Özuygur Ermiş et al., Turkish Journal of Medical Sciences, doi:10.3906/sag-2009-64

Retrospective 370 hospitalized patients, 222 receiving HCQ+AZ and 148 receiving HCQ, showing mortality OR 0.61 [0.23-1.59], p = 0.31 for the addition of AZ.

Özuygur Ermiş et al., 8/4/2021, peer-reviewed, 13 authors.

Hydroxychloroquine Prophylaxis against Coronavirus Disease-19: Practice Outcomes among Health-Care Workers

Bhatt et al., medRxiv, doi:10.1101/2021.08.02.21260750 (Preprint)

Observational study of 927 low-risk healthcare workers in India, 731 volunteering for weekly HCQ prophylaxis, showing higher cases with treatment in unadjusted results. Clinical outcome was in the protocol, however no information on which patients were symptomatic is provided. There were no adverse events and no hospitalizations or deaths. Adherence was very low, decreasing weekly, with almost all participants discontinuing by week 11. The majority of infections occurred in later weeks when adherence was very low, and there was no per protocol analysis. #ECR/206/Inst/GJ/2013/RR-20.

risk of case, 49.3% higher, RR 1.49, p = 0.02, treatment 167 of 731 (22.8%), control 30 of 196 (15.3%).

Bhatt et al., 8/4/2021, prospective, India, South Asia, preprint, 4 authors.

Clinical characteristics and treatment outcomes of severe (ICU) COVID-19 patients in Saudi Arabia: A single centre study

Alghamdi et al., Saudi Pharmaceutical Journal, doi:10.1016/j.jsps.2021.08.008

Retrospective 171 ICU patients in Saudi Arabia showing no significant difference for HCQ treatment in unadjusted results.

risk of death, 39.2% higher, RR 1.39, p = 0.52, treatment 29 of 128 (22.7%), control 7 of 43 (16.3%).

Excluded in after exclusion results of meta analysis: unadjusted results with no group details, very late stage, ICU patients.

Alghamdi et al., 8/4/2021, retrospective, Saudi Arabia, Middle East, peer-reviewed, 1 author.

COVID-19 in hospitalized patients in 4 hospitals in San Isidro, Buenos Aires, Argentina

Barra et al., medRxiv, doi:10.1101/2021.07.30.21261220 (Preprint)

Retrospective 668 hospitalized patients in Argentina, 18 treated with HCQ, not showing a significant difference in unadjusted results.

risk of death, 10.8% lower, RR 0.89, p = 1.00, treatment 2 of 18 (11.1%), control 81 of 650 (12.5%), NNT 74, unadjusted.

Excluded in after exclusion results of meta analysis: unadjusted results with no group details.

Barra et al., 7/31/2021, retrospective, Argentina, South America, preprint, 12 authors, average treatment delay 5.0 days.

Doxycycline is a safe alternative to Hydroxychloroquine + Azithromycin to prevent clinical worsening and hospitalization in mild COVID-19 patients: An open label randomized clinical trial (DOXYCOV)

Sobngwi et al., medRxiv, doi:10.1101/2021.07.25.21260838 (Preprint)

RCT 194 mild/asymptomatic low-risk patients in Cameroon, 97 treated with HCQ+AZ and 97 treated with doxycycline, showing 2.1% symptomatic patients at day 10 with HCQ+AZ, versus 4.3% with doxycycline, but without statistical significance. There were only 6 patients with symtoms at day 10. There was no mortality or hospitalization, and no major adverse events.

risk of no recovery, 51.6% lower, RR 0.48, p = 0.44, treatment 2 of 95 (2.1%), control 4 of 92 (4.3%), NNT 45, day 10.

risk of no recovery, 3.2% lower, RR 0.97, p = 1.00, treatment 18 of 95 (18.9%), control 18 of 92 (19.6%), NNT 162, day 3.

risk of no viral clearance, 3.2% lower, RR 0.97, p = 0.88, treatment 32 of 95 (33.7%), control 32 of 92 (34.8%), NNT 91, day 10.

Sobngwi et al., 7/29/2021, Randomized Controlled Trial, Cameroon, Africa, preprint, 16 authors, dosage 400mg days 1-5, this trial compares with another treatment - results may be better when compared to placebo.

The effect of hydroxychloroquine against SARS-CoV-2 infection in rheumatoid arthritis patients

Küçükakkaş et al., Research Square, doi:10.21203/rs.3.rs-43812/v1 (Preprint)

Retrospective 17 rheumatoid arthritis COVID-19+ patients, 7 on HCQ treatment, showing no significant differences. They study reports only including hospitalized patients, but the results include non-hospitalized patients. Results do not reflect potential difference in the probability that a case is serious enough to have been tested and identified. Few group details are provided (even the age of patients in each group is not specified).

risk of ICU admission, 42.9% higher, RR 1.43, p = 1.00, treatment 1 of 7 (14.3%), control 1 of 10 (10.0%).

Excluded in after exclusion results of meta analysis: minimal details of groups provided.

Küçükakkaş et al., 7/20/2021, retrospective, Turkey, Europe, preprint, 2 authors.

Epidemiology and Clinical Characteristics in Individuals with Confirmed SARS-CoV-2 Infection During the Early COVID-19 Pandemic in Saudi Arabia

Alhamlan et al., medRxiv, doi:10.1101/2021.07.13.21260428 (Preprint)

Retrospective hospitalized patients in Saudi Arabia showing higher mortality with most treatments although not reaching statistical significance. Confounding by indication, time, or other factors is likely (a 19x higher risk with lopinavir/ritonavir and 3.5x higher risk with azithromycin is not supported by other studies for example). The number of patients treated with HCQ is not provided.

risk of death, 52.0% higher, HR 1.52, p = 0.57.

Excluded in after exclusion results of meta analysis: substantial unadjusted confounding by indication likely, substantial confounding by time likely due to declining usage over the early stages of the pandemic when overall treatment protocols improved dramatically.

Alhamlan et al., 7/16/2021, retrospective, database analysis, Saudi Arabia, Middle East, preprint, 10 authors.

Evaluation of the Effects of Remdesivir and Hydroxychloroquine on Viral Clearance in COVID-19

Barrat-Due et al., Annals of Internal Medicine, doi:10.7326/M21-0653

Small RCT in Norway with 52 HCQ and 42 remdesivir patients, showing no significant differences with treatment. Add-on trial to WHO Solidarity. NCT04321616.

risk of death, 120.0% higher, RR 2.20, p = 0.35, treatment 4 of 45 (8.9%), control 2 of 48 (4.2%), adjusted.

Barrat-Due et al., 7/13/2021, Double Blind Randomized Controlled Trial, Norway, Europe, peer-reviewed, 41 authors, average treatment delay 8.0 days, trial NCT04321616.

Outcome and death risk of diabetes patients with Covid-19 receiving pre-hospital and in-hospital metformin therapies

Tamura et al., Diabetology & Metabolic Syndrome, doi:10.1186/s13098-021-00695-8

Retrospective 188 hospitalized patients in Brazil, showing higher risk of mortality with HCQ. Relatively few patients received HCQ. The results are likely subject to confounding by indication with treatment more likely for severe cases, and severity was not used in adjustments. Confounding by time is likely, with declining use of HCQ and improving SOC over the study period.

risk of death, 299.0% higher, OR 3.99, p = 0.04, treatment 25, control 163, adjusted, multivariable, RR approximated with OR.

Excluded in after exclusion results of meta analysis: substantial unadjusted confounding by indication likely, substantial confounding by time likely due to declining usage over the early stages of the pandemic when overall treatment protocols improved dramatically.

Tamura et al., 7/13/2021, retrospective, Brazil, South America, peer-reviewed, 4 authors, study period 10 March, 2020 - 13 November, 2020.

Lopinavir-ritonavir and hydroxychloroquine for critically ill patients with COVID-19: REMAP-CAP randomized controlled trial

Arabi et al., Intensive Care Medicine

Very late stage RCT with 50 ICU patients treated with HCQ, 255 lopinavir-ritonavir patients, and 27 combined therapy patients, showing higher mortality with all treatments. REMAP-CAP. NCT02735707.

risk of death, 44.5% higher, RR 1.44, p = 0.01, treatment 17 of 49 (34.7%), control 106 of 353 (30.0%), adjusted, OR converted to RR, multivariable.

Arabi et al., 7/12/2021, Randomized Controlled Trial, multiple countries, multiple regions, peer-reviewed, 1 author, trial NCT02735707.

French Multicentre Observational Study on SARS-CoV-2 infections Intensive care initial management: the FRENCH CORONA Study

Roger et al., Anaesthesia Critical Care & Pain Medicine, doi:10.1016/j.accpm.2021.100931

Prospective study of 966 ICU patients in France, 289 treated with HCQ, showing no significant difference with treatment. Time based confounding is likely because HCQ became increasingly controversial and less used over the time covered, while overall treatment protocols during this period improved dramatically, i.e., more control patients likely come later in the period when treatment protocols were greatly improved.

risk of death, no change, RR 1.00, p = 0.94, treatment 53 of 289 (18.3%), control 120 of 677 (17.7%), OR converted to RR.

Excluded in after exclusion results of meta analysis: substantial confounding by time likely due to declining usage over the early stages of the pandemic when overall treatment protocols improved dramatically.

Roger et al., 7/10/2021, prospective, France, Europe, peer-reviewed, 34 authors, average treatment delay 8.0 days.

Multi-institutional Analysis of 200 COVID-19 Patients treated with ECMO:Outcomes and Trends

Jacobs et al., The Annals of Thoracic Surgery, doi:10.1016/j.athoracsur.2021.06.026

Prospective study of 200 ECMO patients showing no significant difference in unadjusted results for HCQ treatment. Time based confounding is likely because HCQ became increasingly controversial and less used over the time covered (as shown in figure 4), while overall treatment protocols during this period improved dramatically, i.e., more control patients likely come later in the period when treatment protocols were greatly improved.

risk of death, 6.6% lower, RR 0.93, p = 0.74, treatment 24 of 46 (52.2%), control 86 of 154 (55.8%), NNT 27.

Excluded in after exclusion results of meta analysis: unadjusted results with no group details, substantial confounding by time likely due to declining usage over the early stages of the pandemic when overall treatment protocols improved dramatically.

Jacobs et al., 7/6/2021, prospective, USA, North America, peer-reviewed, 14 authors.

COVID-19 in Individuals Treated With Long-Term Hydroxychloroquine: A Propensity Score-Matched Analysis of Cicatricial Alopecia Patients

Shaw et al., Journal of Drugs in Dermatology, doi:10.36849/JDD.5843

PSM retrospective 144 alopecia patients in the USA, showing lower risk of COVID-19 with HCQ prophylaxis. The supplemental appendix is not available.

risk of case, 13.0% lower, OR 0.87, p = 0.006, treatment 45, control 99, adjusted, propensity score matching, multivariable, RR approximated with OR.

Shaw et al., 7/1/2021, retrospective, USA, North America, peer-reviewed, 10 authors, study period 1 March, 2020 - 15 May, 2020.

Hydroxychloroquine and Azithromycin Treatment of Hospitalized Patients Infected with SARS-CoV-2 in Senegal from March to October 2020

Taieb et al., J. Clin. Med. 2021, doi:10.3390/jcm10132954

Retrospective 926 patients in Senegal, 674 treated with HCQ+AZ, showing significantly higher hospital discharge at day 15 with treatment.

risk of no hospital discharge, 38.7% lower, OR 0.61, p = 0.02, treatment 674, control 252, multivariate, RR approximated with OR.

Taieb et al., 6/30/2021, retrospective, Senegal, Africa, peer-reviewed, 29 authors, average treatment delay 6.0 days.

Pharmacoepidemiology, Machine Learning and COVID-19: An intent-to-treat analysis of hydroxychloroquine, with or without azithromycin, and COVID-19 outcomes amongst hospitalized US Veterans

Gerlovin et al., American Journal of Epidemiology, doi:10.1093/aje/kwab183

Retrospective 1,769 hospitalized patients in the USA showing no significant differences for HCQ, and higher intubation for HCQ+AZ.

risk of death, 22.0% higher, HR 1.22, p = 0.18, treatment 90 of 429 (21.0%), control 141 of 770 (18.3%), adjusted, HCQ+AZ.

risk of death, 21.0% higher, HR 1.21, p = 0.33, treatment 49 of 228 (21.5%), control 141 of 770 (18.3%), adjusted, HCQ.

risk of mechanical ventilation, 55.0% higher, HR 1.55, p = 0.02, treatment 64 of 429 (14.9%), control 69 of 770 (9.0%), adjusted, HCQ+AZ.

risk of mechanical ventilation, 33.0% higher, HR 1.33, p = 0.25, treatment 32 of 228 (14.0%), control 69 of 770 (9.0%), adjusted, HCQ.

Gerlovin et al., 6/24/2021, retrospective, USA, North America, peer-reviewed, 21 authors.

Repurposing the Combination Drug of Favipiravir, Hydroxychloroquine and Oseltamivir as a Potential Inhibitor Against SARS-CoV-2: A Computational Study

Yadav et al., Research Square, doi:10.21203/rs.3.rs-628277/v1 (Preprint)

In Silico study showing stronger inhibition of SAR-CoV-2 for HCQ+favipiravir+oseltamivir compared to any of these alone or combinations of two of these drugs.

Yadav et al., 6/21/2021, preprint, 2 authors.

In Silico studies are an important part of preclinical research, however results may be very different in vivo.

Assessing the efficacy and safety of hydroxychloroquine as outpatient treatment of COVID-19: a randomized controlled trial

Schwartz et al., CMAJ Open, doi:10.9778/cmajo.20210069

Small early terminated late treatment RCT not showing significant differences. The HCQ group was a median of 7 days from symptom onset at baseline, which may not include the delay delivering the medication. From the 4 HCQ hospitalizations, only one is in the per-protocol analysis, and that patient was hospitalized one day after randomization (authors do not specify if the patient received and took any HCQ before the hospitalization). The trial was terminated early due to the fraudulent Lancet article (wording here is notably different between the submitted and published versions). Per-protocol analysis, the submitted version, and the peer-review comments (two reviewers, only one with substantial feedback) are in the supplementary material.

risk of ICU admission, 133.3% higher, RR 2.33, p = 1.00, treatment 1 of 111 (0.9%), control 0 of 37 (0.0%), continuity correction due to zero event.

risk of hospitalization, 533.3% higher, RR 6.33, p = 0.57, treatment 4 of 111 (3.6%), control 0 of 37 (0.0%), continuity correction due to zero event.

risk of ICU admission, 141.9% higher, RR 2.42, p = 1.00, treatment 1 of 74 (1.4%), control 0 of 31 (0.0%), continuity correction due to zero event, per-protocol.

risk of hospitalization, 141.9% higher, RR 2.42, p = 1.00, treatment 1 of 74 (1.4%), control 0 of 31 (0.0%), continuity correction due to zero event, per-protocol.

Schwartz et al., 6/18/2021, Double Blind Randomized Controlled Trial, Canada, North America, peer-reviewed, 20 authors, average treatment delay 7.0 days, dosage 800mg day 1, 400mg days 2-5.

An in vitro study of dual drug combinations of anti-viral agents, antibiotics, and/or hydroxychloroquine against the SARS-CoV-2 virus isolated from hospitalized patients in Surabaya, Indonesia

Purwati et al., PLOS One, doi:10.1371/journal.pone.0252302 (In Vitro)

In Vitro study of combinations of drugs showing antiviral efficacy of HCQ alone and in combination with AZ, favipiravir, and doxycycline. No high levels of cytotoxicity were observed, and authors conclude that using a combination of drugs can reduce the degree of cytotoxicity, increase antiviral activity, reduce the effect on pro-inflammatory markers, and increase anti-inflammatory response.

Purwati et al., 6/18/2021, peer-reviewed, 16 authors.

In Vitro studies are an important part of preclinical research, however results may be very different in vivo.

Clinical Course and Risk Factors for In-Hospital Mortality of 205 Patients with SARS-CoV-2 Pneumonia in Como, Lombardy Region, Italy

Turrini et al., Vaccines, 10.3390/vaccines9060640

Retrospective 205 patients in Italy, 160 treated with HCQ, showing lower mortality with treatment in multivariate analysis, but not reaching statistical significance.

risk of death, 9.8% lower, RR 0.90, p = 0.15, treatment 103 of 160 (64.4%), control 33 of 45 (73.3%), NNT 11, adjusted, OR converted to RR, multivariate.

Turrini et al., 6/11/2021, retrospective, Italy, Europe, peer-reviewed, 16 authors.

Lack of efficacy of hydroxychloroquine and azithromycin in patients hospitalized for COVID-19 pneumonia: A retrospective study

Saib et al., PLOS ONE, doi:10.1371/journal.pone.0252388

203 hospitalized patients in France, not showing significant differences with treatment. Confounding by indication is likely. Authors do not discuss confounding.

risk of death/intubation, 125.0% higher, RR 2.25, p = 0.23, treatment 9 of 52 (17.3%), control 4 of 52 (7.7%), PSM.

Excluded in after exclusion results of meta analysis: substantial unadjusted confounding by indication likely.

Saib et al., 6/9/2021, prospective, propensity score matching, France, Europe, peer-reviewed, 9 authors, average treatment delay 7.2 days.

Safety and efficacy of antiviral therapy alone or in combination in COVID-19 - a randomized controlled trial (SEV COVID Trial)

Singh et al., medRxiv, doi:0.1101/2021.06.06.21258091 (Preprint)

Very small early terminated RCT in India, showing lower mortality but without statistical significance with the very small sample size. Time since symptom onset is not provided. The recovery percentage for non-severe group B (86.7%) does not match any number of recoveries, we have used the closest number (15/17).

risk of death, 47.5% lower, RR 0.53, p = 0.45, treatment 3 of 20 (15.0%), control 6 of 21 (28.6%), NNT 7.4, severe.

risk of death, 50.0% lower, RR 0.50, p = 0.48, treatment 3 of 37 (8.1%), control 6 of 37 (16.2%), NNT 12, all patients.

risk of no recovery, 14.1% lower, RR 0.86, p = 0.76, treatment 9 of 20 (45.0%), control 11 of 21 (52.4%), NNT 14, severe.

risk of no recovery, 8.3% lower, RR 0.92, p = 1.00, treatment 11 of 37 (29.7%), control 12 of 37 (32.4%), NNT 37, all patients.

Singh et al., 6/8/2021, Randomized Controlled Trial, India, South Asia, preprint, 13 authors, this trial uses multiple treatments in the treatment arm (combined with ribavirin) - results of individual treatments may vary.

Hydroxychloroquine for SARS CoV2 Prophylaxis in Healthcare Workers – A Multicentric Cohort Study Assessing Effectiveness and Safety

Badyal et al., Journal of the Association of Physicians of India, Volume 69, June 2021

Prophylaxis study with 12,089 Indian healthcare workers, showing lower risk of COVID-19 cases with treatment, and increasingly lower risk for longer durations of HCQ prophylaxis. The appendices are not currently available.

risk of case, 60.1% lower, RR 0.40, p < 0.001, treatment 247 of 617 (40.0%), control 611 of 1,473 (41.5%), adjusted, OR converted to RR, >=6 weeks, logistic regression.

risk of case, 35.1% lower, RR 0.65, p = 0.003, treatment 88 of 185 (47.6%), control 611 of 1,473 (41.5%), adjusted, OR converted to RR, 4-5 weeks, logistic regression.

risk of case, 23.2% lower, RR 0.77, p = 0.04, treatment 80 of 181 (44.2%), control 611 of 1,473 (41.5%), adjusted, OR converted to RR, 2-3 weeks, logistic regression.

Badyal et al., 6/7/2021, prospective, India, South Asia, peer-reviewed, 18 authors.

Outcomes of 2,111 COVID-19 hospitalised patients treated with 2 hydroxychloroquine/azithromycin and other regimens in Marseille, France: a 3 monocentric retrospective analysis

Lagier et al., Preprint (Preprint)

Retrospective 2,011 hospitalized patients in France, median age 67, showing lower mortality with HCQ+AZ, and further benefit with the addition of zinc.

risk of death, 32.0% lower, RR 0.68, p = 0.004, treatment 93 of 1,270 (7.3%), control 146 of 841 (17.4%), NNT 10.0, adjusted, weighted multivariate Cox proportional hazards model.

Lagier et al., 6/4/2021, retrospective, France, Europe, preprint, 32 authors.

Safety and Efficacy of Hydroxychloroquine for Treatment of Non-Severe COVID-19 in Adults in Uganda: A Randomized Open Label Phase II Clinical Trial

Byakika-Kibwika et al., Research Square, doi:10.21203/rs.3.rs-506195/v1 (Preprint)

Small 105 patient RCT in Uganda showing no significant differences. No mortality was reported. The patients were very young (median age 32), recovering in a median time of 3 days with standard of care, so there is little room for a treatment to make improvements. Time since symptom onset is not specified, but the distribution of symptoms at baseline suggests that the enrollment is relatively late within a cohort of low risk patients.

recovery time, no change, relative time 1.00, p = 0.91, treatment 36, control 29.

relative improvement in Ct value, 29.3% better, RR 0.71, p = 0.47, treatment 15, control 15.

risk of no viral clearance, 2.6% higher, RR 1.03, p = 1.00, treatment 35 of 55 (63.6%), control 31 of 50 (62.0%), day 6.

risk of no viral clearance, 6.7% higher, RR 1.07, p = 0.85, treatment 27 of 55 (49.1%), control 23 of 50 (46.0%), day 10.

Byakika-Kibwika et al., 6/4/2021, Randomized Controlled Trial, Uganda, Africa, preprint, 17 authors.

Azithromycin and hydroxychloroquine in hospitalised patients with confirmed COVID-19–a randomised double-blinded placebo-controlled trial

Sivapalan et al., European Respiratory Journal, doi:10.1183/13993003.00752-2021

Early terminated late stage (8 days from onset, 59% on oxygen) RCT not showing statistically significant differences. NCT04322396 ProPAC-COVID. NNF20SA0062834.

risk of death, 92.0% lower, RR 0.08, p = 0.32, treatment 1 of 61 (1.6%), control 2 of 56 (3.6%), adjusted.

risk of ICU admission, 22.4% higher, RR 1.22, p = 1.00, treatment 4 of 61 (6.6%), control 3 of 56 (5.4%).

relative days alive and discharged from hospital within 14 days (inverse), 8.4% worse, RR 1.08, p = 0.36, treatment 61, control 56, adjusted.

Sivapalan et al., 6/3/2021, Double Blind Randomized Controlled Trial, Denmark, Europe, peer-reviewed, 32 authors, average treatment delay 8.0 days, trial NCT04322396.

The effect of Hydroxychloroquine use due to rheumatic disease on the risk of Covid-19 infection and its course

Korkmaz et al., Authorea, doi:10.22541/au.162257516.68665404/v1 (Preprint)

Retrospective 683 patients in a rheumatology department, 384 chronic HCQ users and 299 control patients, showing no mortality for HCQ users vs. 2 deaths in the control group, and significantly fewer cases for HCQ users.

risk of death, 82.1% lower, RR 0.18, p = 0.19, treatment 0 of 385 (0.0%), control 2 of 299 (0.7%), NNT 150, relative risk is not 0 because of continuity correction due to zero events.

risk of case, 93.7% lower, RR 0.06, p < 0.001, treatment 2 of 395 (0.5%), control 24 of 299 (8.0%), NNT 13.

Korkmaz et al., 6/1/2021, retrospective, Turkey, Europe, preprint, 4 authors.

Hydroxychloroquine as a primary prophylactic agent against sars-cov-2 infection: a cohort study

Kamstrup et al., International Journal of Infectious Diseases, doi:10.1016/j.ijid.2021.05.076

Retrospective HCQ users in Denmark, not showing a significant difference, however authors do not adjust for the very different baseline risk for systemic autoimmune disease patients.

Authors appear unaware of research in the area, for example saying that "currently, no obvious connection exists between a known rheumatological disorder and the risk of contracting SARS-CoV-2". Many papers show that the risk of COVID-19 for systemic autoimmune disease patients is much higher overall, e.g., Ferri et al. show OR 4.42, p<0.001 [Ferri].

Supplementary data is not currently available.

1. Ferri at al., Clinical Rheumatology, doi:0.1007/s10067-020-05334-7, COVID-19 and rheumatic autoimmune systemic diseases: report of a large Italian patients series, https://link.springer.com/article/10.1007/s10067-020-05334-7.

risk of hospitalization, 44.0% higher, OR 1.44, p = 0.25, treatment 5,488, control 54,846, RR approximated with OR.

risk of case, 10.0% lower, HR 0.90, p = 0.23, treatment 188 of 5,488 (3.4%), control 2,040 of 54,846 (3.7%), NNT 340, adjusted Cox proportional hazards regression.

Excluded in after exclusion results of meta analysis: not fully adjusting for the different baseline risk of systemic autoimmune patients.

Kamstrup et al., 6/1/2021, retrospective, population-based cohort, Denmark, Europe, peer-reviewed, 21 authors.

Hydroxychloroquine and Tocilizumab in the Treatment of COVID-19: A Longitudinal Observational Study

Ramírez-García et al., Archivos de Medicina Universitaria

Retrospective 403 hospitalized patients in Spain, showing lower mortality with treatment, however authors do not adjust for the differences between the groups. Confounding by indication is likely.

risk of death, 67.0% lower, RR 0.33, p < 0.001, treatment 48 of 350 (13.7%), control 22 of 53 (41.5%), NNT 3.6.

risk of ICU admission, 6.0% higher, RR 1.06, p = 1.00, treatment 35 of 350 (10.0%), control 5 of 53 (9.4%).

Excluded in after exclusion results of meta analysis: excessive unadjusted differences between groups, substantial unadjusted confounding by indication likely.

Ramírez-García et al., 5/31/2021, retrospective, Spain, Europe, peer-reviewed, 5 authors.

Observational Study on 255 Mechanically Ventilated Covid Patients at the Beginning of the USA Pandemic

Smith et al., medRxiv, doi:10.1101/2021.05.28.21258012 (Preprint)

Retrospective 255 mechanical ventilation patients in USA, showing that weight-adjusted HCQ+AZ improved survival by over 100%. QTc prolongation did not correlate with cumulative HCQ dose or HCQ serum level.

Although authors mention immortal time bias, full details on the timing of HCQ administration is not provided and this is not fully addressed. Survival curves indicate immortal time bias will significantly change results, although the observed benefit appears to exceed the potential bias.

risk of death, 27.2% lower, RR 0.73, p = 0.002, treatment 19 of 37 (51.4%), control 182 of 218 (83.5%), NNT 3.1, OR converted to RR, >3g HCQ and >1g AZ, multivariable cox proportional hazard regression.

risk of death, 92.9% lower, OR 0.07, p < 0.001, ≥80mg/kg HCQ and >1g AZ, RR approximated with OR.

Excluded in after exclusion results of meta analysis: immortal time bias may significantly affect results.

Smith et al., 5/31/2021, retrospective, USA, North America, preprint, 4 authors.

Optimizing the Use of Hydroxychloroquine in the Management of COVID-19 Given Its Pharmacological Profile

Ali et al., Journal of Pharmaceutical Research International, doi:10.9734/jpri/2020/v32i830468 (Dosing)

Review of the mechanisms of action, pharmacokinetics and toxicity of HCQ, recommending use as early as possible with a loading dose in 3-4 divided doses to minimize toxicity, and daily maintenance divided into two doses, continued until remission.

Ali et al., 5/29/2021, peer-reviewed, 8 authors.

Early Treatment with Hydroxychloroquine and Azithromycin in 10,429 COVID-19 Outpatients: A Monocentric Retrospective Cohort Study

Million et al., Reviews in Cardiovascular Medicine, doi:10.31083/j.rcm2203116 (preprint 5/27/2021)

Retrospective 10,429 outpatients in France, 8,315 treated with HCQ+AZ a median of 4 days from symptom onset, showing significantly lower mortality with treatment.

risk of death, 83.0% lower, HR 0.17, p < 0.001, treatment 5 of 8,315 (0.1%), control 11 of 2,114 (0.5%), NNT 217, adjusted.

risk of ICU admission, 44.0% lower, HR 0.56, p = 0.18, treatment 17 of 8,315 (0.2%), control 7 of 2,114 (0.3%), NNT 789, adjusted.

risk of hospitalization, 4.0% lower, HR 0.96, p = 0.77, treatment 214 of 8,315 (2.6%), control 64 of 2,114 (3.0%), adjusted.

Million et al., 5/27/2021, retrospective, France, Europe, peer-reviewed, 28 authors, average treatment delay 4.0 days, dosage 200mg tid days 1-10, this trial uses multiple treatments in the treatment arm (combined with AZ) - results of individual treatments may vary.

Pre-exposure Prophylaxis With Various Doses of Hydroxychloroquine Among Healthcare Personnel With High-Risk Exposure to COVID-19: A Randomized Controlled Trial

Syed et al., Cureus, doi:10.7759/cureus.20572 (preprint 5/17/2021)

Small PrEP RCT of low risk patients, showing no significant differences. Authors report that there was no hospitalization, ICU care, or death from COVID-19, however table 3 of the preprint shows severe events labeled as "requiring hospitalization". Symptomatology and disease severity results in tables 3 and 4 appear inconsistent. NCT04359537.

risk of symptomatic case, 59.7% higher, RR 1.60, p = 0.41, treatment 10 of 48 (20.8%), control 6 of 46 (13.0%), group 1.

risk of symptomatic case, 110.5% higher, RR 2.10, p = 0.13, treatment 14 of 51 (27.5%), control 6 of 46 (13.0%), group 2.

risk of symptomatic case, 16.4% lower, RR 0.84, p = 0.77, treatment 6 of 55 (10.9%), control 6 of 46 (13.0%), NNT 47, group 3.

risk of case, 91.7% higher, RR 1.92, p = 0.12, treatment 15 of 38 (39.5%), control 7 of 34 (20.6%), group 1.

risk of case, 136.6% higher, RR 2.37, p = 0.02, treatment 19 of 39 (48.7%), control 7 of 34 (20.6%), group 2.

risk of case, 21.4% higher, RR 1.21, p = 0.77, treatment 8 of 32 (25.0%), control 7 of 34 (20.6%), group 3.

Syed et al., 5/17/2021, Randomized Controlled Trial, Pakistan, South Asia, peer-reviewed, 8 authors, trial NCT04359537.

Hydroxychloroquine For Prophylaxis Of COVID-19 In Health Workers: A Randomized Clinical Trial

Rojas-Serrano et al., medRxiv, doi:10.1101/2021.05.14.21257059 (Preprint)

Early terminated HCQ PrEP RCT with 62 HCQ and 65 placebo patients, showing 82% lower cases with treatment, p = 0.12. NCT04318015.

If the trial is continued and the same event rate is observed, statistical significance will be reached after adding about 16 patients per arm.

risk of symptomatic case, 82.0% lower, RR 0.18, p = 0.12, treatment 1 of 62 (1.6%), control 6 of 65 (9.2%), NNT 13, adjusted.

Rojas-Serrano et al., 5/16/2021, Double Blind Randomized Controlled Trial, Mexico, North America, preprint, 8 authors, trial NCT04318015.

SARS-CoV-2 Persistent Viral Shedding in the Context of Hydroxychloroquine-Azithromycin Treatment

Drancourt et al., Viruses, doi:10.3390/v13050890

Retrospective 3,737 patients in France, showing lower risk of persistent viral shedding with HCQ+AZ treatment.

Drancourt et al., 5/12/2021, peer-reviewed, 11 authors, this trial uses multiple treatments in the treatment arm (combined with AZ) - results of individual treatments may vary.

Predictors for inpatient mortality during the first wave of the SARS-CoV-2 pandemic: A retrospective analysis

Sammartino et al., PLOS One, doi:10.1371/journal.pone.0251262

Retrospective 1,108 hospitalized patients in New York showing significantly higher mortality with HCQ treatment.

Time based confounding is very likely because HCQ became increasingly controversial and less used over the time covered (Mar - Jun 2020), while overall treatment protocols during this period improved dramatically, i.e., more control patients likely come later in the period when treatment protocols were greatly improved. Authors note that for every week or month later that a person was admitted, their risk of death dropped by 16% and 49%, respectively, yet they do not consider time based confounding.

risk of death, 240.0% higher, OR 3.40, p = 0.002, treatment 137, control 191, PSM, model 1a, RR approximated with OR.

Excluded in after exclusion results of meta analysis: substantial confounding by time likely due to declining usage over the early stages of the pandemic when overall treatment protocols improved dramatically.

Sammartino et al., 5/10/2021, retrospective, propensity score matching, USA, North America, peer-reviewed, 7 authors.

Review of four major biomolecular target sites for COVID-19 and possible inhibitors as treatment interventions

Vigbedor et al., Journal of Applied Pharmaceutical Science, doi:10.7324/JAPS.2021.110825 (Review)

Review of major target sites in SARS-CoV-2 and the host organism along with potential inhibitors.

Vigbedor et al., 5/8/2021, peer-reviewed, 8 authors.

Risk Factors for Mortality in COVID-19 Hospitalized Patients in Piedmont, Italy: Results from the Multicenter, Regional, CORACLE Registry

De Rosa et al., J. Clin. Med., doi:10.3390/jcm10091951

Retrospective 1,538 hospitalized patients in Italy, showing only HCQ associated with reduced mortality. Authors analyze mortality amongst those that were alive at day 7 to avoid survival time bias due to drug recording requiring a minimum of 5 days treatment.

risk of death, 35.0% lower, RR 0.65, p = 0.02, treatment 118 of 731 (16.1%), control 80 of 280 (28.6%), NNT 8.0, adjusted, OR converted to RR, multivariate logistic regression, patients alive at day 7.

risk of death, 36.0% lower, RR 0.64, p < 0.001, treatment 207 of 1,019 (20.3%), control 215 of 519 (41.4%), NNT 4.7, adjusted, OR converted to RR, multivariate logistic regression, all patients.

De Rosa et al., 5/1/2021, retrospective, Italy, Europe, peer-reviewed, 20 authors, average treatment delay 6.0 days.

The Effect of Pre-admission Hydroxychloroquine Treatment on COVID-19-Related Intensive Care Follow-up in Geriatric Patients

Çiyiltepe et al., South. Clin. Ist. Euras., doi:10.14744/scie.2021.89847

Retrospective 147 ICU patients in Turkey, showing no significant difference in outcomes based on HCQ treatment before ICU admission. This is not very informative, for example we do not know if HCQ treated patients were much less likely to be admitted to the ICU.

risk of death, 3.2% lower, RR 0.97, p = 0.85, treatment 69 of 95 (72.6%), control 39 of 52 (75.0%), NNT 42.

Excluded in after exclusion results of meta analysis: treatment group only includes patients where treatment failed resulting in ICU admission.

Çiyiltepe et al., 4/30/2021, retrospective, Turkey, Europe, peer-reviewed, 5 authors.

Favipiravir and Hydroxychloroquine Combination Therapy in Patients with Moderate to Severe COVID19 (FACCT Trial): An Open-Label, Multicenter, Randomized, Controlled Trial

Bosaeed et al., Infect. Dis. Ther., doi:10.1007/s40121-021-00496-6

RCT 254 very late stage (93% on oxygen, 17% in ICU at baseline) hospitalized patients in Saudi Arabia not showing significant differences with HCQ+favipiravir treatment. Only SaO₂ < 94% patients were eligible, however the actual SaO₂ of enrolled patients is not provided.

risk of death, 3.7% lower, RR 0.96, p = 0.91, treatment 14 of 125 (11.2%), control 15 of 129 (11.6%), NNT 234, 90 days.

risk of death, 28.6% lower, RR 0.71, p = 0.45, treatment 9 of 125 (7.2%), control 13 of 129 (10.1%), NNT 35, 28 days.

risk of death, 65.1% higher, RR 1.65, p = 0.68, treatment 8 of 125 (6.4%), control 5 of 129 (3.9%), 14 days.

risk of mechanical ventilation, 8.4% higher, RR 1.08, p = 0.78, treatment 21 of 125 (16.8%), control 20 of 129 (15.5%).

risk of ICU admission, 31.0% higher, RR 1.31, p = 0.24, treatment 33 of 125 (26.4%), control 26 of 129 (20.2%).

recovery time, 28.6% higher, relative time 1.29, p = 0.29, treatment 125, control 129.

hospitalization time, 12.5% higher, relative time 1.12, p = 0.42, treatment 125, control 129.

risk of no viral clearance, 2.6% lower, RR 0.97, p = 0.75, treatment 100 of 125 (80.0%), control 106 of 129 (82.2%), NNT 46.

Excluded in after exclusion results of meta analysis: very late stage, >50% on oxygen/ventilation at baseline.

Bosaeed et al., 4/30/2021, Randomized Controlled Trial, Saudi Arabia, Middle East, peer-reviewed, 30 authors, average treatment delay 5.85 days.

Decreased in-hospital mortality associated with aspirin administration in hospitalized patients due to severe COVID-19

Haji Aghajani et al., Journal of Medical Virology, doi:10.1002/jmv.27053

Retrospective 991 hospitalized patients in Iran, showing lower mortality with HCQ, not reaching statistical significance.

risk of death, 19.5% lower, HR 0.81, p = 0.09, treatment 553, control 438, adjusted, Cox proportional hazards, RR approximated with OR.

Haji Aghajani et al., 4/29/2021, retrospective, Iran, Middle East, peer-reviewed, 7 authors.

Decreased In-Hospital Mortality Associated with Aspirin Administration in Hospitalized Patients Due to Severe COVID-19

Aghajani et al., Journal of Medical Virology, doi:10.1002/jmv.27053

Retrospective 991 hospitalized patients in Iran focusing on aspirin use but also showing results for HCQ, remdesivir, and favipiravir.

risk of death, 19.5% lower, HR 0.81, p = 0.09, treatment 553, control 438, multivariate Cox proportional regression.

Aghajani et al., 4/29/2021, retrospective, Iran, Middle East, peer-reviewed, 7 authors.

The predictors of COVID-19 mortality in a nationwide cohort of Turkish patients

Kokturk et al., Respiratory Medicine, doi:10.1016/j.rmed.2021.106433

Retrospective 1,500 hospitalized late stage (median SaO₂ 87.7) patients in Turkey, showing no significant difference with HCQ treatment.

risk of death, 3.8% higher, RR 1.04, p = 0.97, treatment 62 of 1,382 (4.5%), control 5 of 118 (4.2%), adjusted, OR converted to RR.

Kokturk et al., 4/28/2021, retrospective, database analysis, Turkey, Europe, peer-reviewed, 68 authors.

An open-label randomized controlled trial evaluating the efficacy of chloroquine/hydroxychloroquine in severe COVID-19 patients

Réa-Neto et al., Scientific Reports, doi:10.1038/s41598-021-88509-9

Early terminated very late stage (99% on oxygen, 81% in ICU, 18% on mechanical ventilation at baseline) RCT with 24 CQ patients, 29 HCQ, and 52 control patients, showing worse clinical outcomes with treatment. NCT04420247.

risk of death, 57.0% higher, RR 1.57, p = 0.20, treatment 16 of 53 (30.2%), control 10 of 52 (19.2%).

risk of mechanical ventilation, 115.0% higher, RR 2.15, p = 0.03, treatment 53, control 52.

9-point scale clinical status, 147.0% higher, OR 2.47, p = 0.02, treatment 53, control 52, RR approximated with OR.

Réa-Neto et al., 4/27/2021, Randomized Controlled Trial, Brazil, South America, peer-reviewed, 6 authors, average treatment delay 8.0 days, trial NCT04420247.

Clinical review of COVID-19 patients presenting to a quaternary care private hospital in South India: A retrospective study

Mohandas et al.,

Retrospective 3,345 hospitalized patients in India, 11.5% treated with HCQ, showing unadjusted higher mortality with treatment. Confounding by indication and time based confounding (due to declining use over the period when overall treatment protocols improved dramatically) are likely.

risk of death, 81.0% higher, RR 1.81, p = 0.007, treatment 27 of 384 (7.0%), control 115 of 2,961 (3.9%).

Excluded in after exclusion results of meta analysis: substantial unadjusted confounding by indication likely, unadjusted results with no group details, substantial confounding by time likely due to declining usage over the early stages of the pandemic when overall treatment protocols improved dramatically.

Mohandas et al., 4/26/2021, retrospective, India, South Asia, peer-reviewed, 6 authors.

Clinical factors associated with death in 3044 COVID-19 patients managed in internal medicine wards in Italy: results from the SIMI-COVID-19 study of the Italian Society of Internal Medicine (SIMI)

Corradini et al., Internal and Emergency Medicine, doi:10.1007/s11739-021-02742-8

Retrospective 3,044 hospitalized COVID-19 patients in Italy, showing HCQ significantly associated with survival in light, mild, and moderate cases in multivariable analysis, but not in severe cases.

risk of death, 70.2% lower, OR 0.30, p < 0.001, treatment 1,439, control 274, adjusted, Table S6, all patients, multivariable, RR approximated with OR.

risk of death, 67.4% lower, OR 0.33, p = 0.01, treatment 641, control 102, adjusted, Table S6, light condition patients, multivariable, RR approximated with OR, early treatment result.

risk of death, 76.8% lower, OR 0.23, p < 0.001, treatment 546, control 71, adjusted, Table S6, mild condition patients, multivariable, RR approximated with OR.

risk of death, 84.2% lower, OR 0.16, p < 0.001, treatment 184, control 64, adjusted, Table S6, moderate condition patients, multivariable, RR approximated with OR.

risk of death, 29.0% higher, OR 1.29, p = 0.73, treatment 68, control 37, adjusted, Table S6, severe condition patients, multivariable, RR approximated with OR.

Corradini et al., 4/24/2021, retrospective, Italy, Europe, peer-reviewed, 60 authors, dosage not specified.

A Cross-Country Analysis of the Determinants of COVID-19 Fatalities

Toya et al., SSRN (Preprint)

Country based analysis finding lower mortality with the use of HCQ.

Toya et al., 4/23/2021, preprint, 2 authors.

Effect of Early Treatment With Hydroxychloroquine or Lopinavir and Ritonavir on Risk of Hospitalization Among Patients With COVID-19 The TOGETHER Randomized Clinical Trial

Reis et al., JAMA Network Open, doi:10.1001/jamanetworkopen.2021.6468

Early terminated RCT in Brazil showing lower mortality and hospitalization with HCQ, but not reaching statistical significance. Although the title includes "early treatment", treatment was relatively late, with most patients being over 5 days from the onset of symptoms. Adverse events were lower in the HCQ group compared to the control group.

The paper indicates the placebo was talc, however the trial protocol shows the "placebo" as vitamin C, for which there are 7 COVID-19 treatment studies as of April 2021 that collectively show significant efficacy.

Results differ significantly from those reported prior to publication. Prior to publication, authors reported an RR for hospitalization or death of 1.0 [0.45-2.21] [ajtmh.org]. Hence the trial may have been accidently terminated due to a data error.

1. ajtmh.org, https://www.ajtmh.org/view/journals/tpmd/104/1/article-p35.xml.

risk of death, 66.0% lower, RR 0.34, p = 1.00, treatment 0 of 214 (0.0%), control 1 of 227 (0.4%), NNT 227, relative risk is not 0 because of continuity correction due to zero events.

risk of hospitalization, 24.0% lower, HR 0.76, p = 0.57, treatment 8 of 214 (3.7%), control 11 of 227 (4.8%), NNT 90, ITT, Cox proportional hazards.

risk of no viral clearance, 4.1% lower, RR 0.96, p = 0.10, treatment 97 of 185 (52.4%), control 102 of 179 (57.0%), NNT 22, adjusted, OR converted to RR, ITT, mixed-effect logistic model.

Reis et al., 4/22/2021, Double Blind Randomized Controlled Trial, Brazil, South America, peer-reviewed, 18 authors, dosage 800mg day 1, 400mg days 2-10, trial NCT04403100 (TOGETHER).

Clinical characteristics and outcome of COVID-19 in patients with rheumatic diseases

Alzahrani et al., Rheumatology International , doi:10.1007/s00296-021-04857-9

Retrospective 47 rheumatic disease patients not finding significant differences with HCQ.

risk of death, 58.7% lower, RR 0.41, p = 1.00, treatment 0 of 14 (0.0%), control 1 of 33 (3.0%), NNT 33, relative risk is not 0 because of continuity correction due to zero events.

risk of mechanical ventilation, 81.0% lower, RR 0.19, p = 0.54, treatment 0 of 14 (0.0%), control 3 of 33 (9.1%), NNT 11, relative risk is not 0 because of continuity correction due to zero events.

risk of severe case, 32.7% lower, RR 0.67, p = 0.70, treatment 2 of 14 (14.3%), control 7 of 33 (21.2%), NNT 14.

Alzahrani et al., 4/15/2021, retrospective, Saudi Arabia, Middle East, peer-reviewed, 3 authors.

Risk of COVID-19 hospitalization and mortality in rheumatic patients treated with hydroxychloroquine or other conventional DMARDs in Italy

Alegiani et al., Rheumatology, doi:10.1093/rheumatology/keab348

Retrospective database analysis case control study of rheumatic patients. When compared with other cDMARDs, HCQ users had significantly lower hospitalization, however there was no significant difference in mortality. Results differ significantly from previous studies, for example showing mortality OR 0.94 [0.83-1.06] for patients with rheumatic disease and mortality OR 0.88 [0.74-1.05] for patients with RA/SLE. Other research shows that the risk of COVID-19 for systemic autoimmune disease patients is much higher overall.

risk of death, 8.0% higher, OR 1.08, p = 0.64, HCQ vs. other cDMARDs, RR approximated with OR.

risk of hospitalization, 18.0% lower, OR 0.82, p = 0.03, HCQ vs. other cDMARDs, RR approximated with OR.

risk of death, 19.0% higher, OR 1.19, p = 0.32, HCQ vs. MTX, RR approximated with OR.

risk of hospitalization, 12.0% lower, OR 0.88, p = 0.17, HCQ vs. MTX, RR approximated with OR.

Alegiani et al., 4/15/2021, retrospective, case control, database analysis, Italy, Europe, peer-reviewed, 16 authors.

Positive impact of oral hydroxychloroquine and povidone-iodine throat spray for COVID-19 prophylaxis: an open-label randomized trial

Seet et al., International Journal of Infectious Diseases, doi:10.1016/j.ijid.2021.04.035

Prophylaxis RCT in Singapore with 3,037 low risk patients, showing lower serious cases, lower symptomatic cases, and lower confirmed cases of COVID-19 with all treatments (ivermectin, HCQ, PVP-I, and Zinc + vitamin C) compared to vitamin C.

Only 71.4% reported >70% adherence, limiting efficacy.

QTc did not statistically significantly differ between baseline and follow-up readings (mean 379 vs 378ms, paired t-test p=0.387).

Meta-analysis of vitamin C in 6 previous trials shows a benefit of 16%, so the actual benefit of ivermectin, HCQ, and PVP-I may be higher. Cluster RCT with 40 clusters.

There were no hospitalizations and no deaths. NCT04446104.

risk of symptomatic case, 35.1% lower, RR 0.65, p = 0.047, treatment 29 of 432 (6.7%), control 64 of 619 (10.3%), NNT 28.

risk of case, 32.0% lower, RR 0.68, p = 0.009, treatment 212 of 432 (49.1%), control 433 of 619 (70.0%), NNT 4.8, adjusted, OR converted to RR, model 6.

Seet et al., 4/14/2021, Cluster Randomized Controlled Trial, Singapore, Asia, peer-reviewed, 15 authors, dosage 400mg day 1, 200mg days 2-42, this trial compares with another treatment - results may be better when compared to placebo, trial NCT04446104.

Clinical characteristics of hospitalised patients with COVID-19 and the impact on mortality: a single-network, retrospective cohort study from Pennsylvania state

Gadhiya et al., BMJ Open, doi:10.1136/bmjopen-2020-042549

Retrospective 283 patients in the USA showing higher mortality with all treatments (not statistically significant). Confounding by indication is likely. In the supplementary appendix, authors note that the treatments were usually given for patients that required oxygen therapy. Oxygen therapy and ICU admission (possibly, the paper includes ICU admission for model 2 in some places but not others) were the only variables indicating severity used in adjustments. Time based confounding is likely because HCQ became increasingly controversial and less used over the time covered (March 1 to May 31, 2020), while overall treatment protocols during this period improved dramatically, i.e., more control patients likely come later in the period when treatment protocols were greatly improved.

risk of death, 4.8% higher, RR 1.05, p = 0.89, treatment 22 of 55 (40.0%), control 33 of 216 (15.3%), adjusted, OR converted to RR, multivariate logistic regression.

Excluded in after exclusion results of meta analysis: substantial confounding by time likely due to declining usage over the early stages of the pandemic when overall treatment protocols improved dramatically, substantial unadjusted confounding by indication likely.

Gadhiya et al., 4/8/2021, retrospective, USA, North America, peer-reviewed, 4 authors.

3219 hospitalised patients with COVID-19 in Southeast Michigan: a retrospective case cohort study

Mulhem et al., BMJ Open, doi:10.1136/bmjopen-2020-042042

Retrospective database analysis of 3,219 hospitalized patients in the USA. Very different results in the time period analysis (Table S2), and results significantly different to other studies for the same medications (e.g., heparin OR 3.06 [2.44-3.83]) suggest significant confounding by indication and confounding by time.

risk of death, 28.3% higher, RR 1.28, p = 0.10, treatment 435 of 2,496 (17.4%), control 81 of 723 (11.2%), adjusted, OR converted to RR, logistic regression.

Excluded in after exclusion results of meta analysis: substantial unadjusted confounding by indication likely, substantial confounding by time likely due to declining usage over the early stages of the pandemic when overall treatment protocols improved dramatically.

Mulhem et al., 4/7/2021, retrospective, database analysis, USA, North America, peer-reviewed, 3 authors.

Clinical outcomes of patients with mild COVID-19 following treatment with hydroxychloroquine in an outpatient setting

Mokhtari et al., International Immunopharmacology, doi:10.1016/j.intimp.2021.107636

Retrospective 28,759 adult outpatients with mild COVID-19 in Iran, 7,295 treated with HCQ, showing significantly lower hospitalization and mortality with treatment.

risk of death, 69.7% lower, RR 0.30, p < 0.001, treatment 27 of 7,295 (0.4%), control 287 of 21,464 (1.3%), NNT 103, adjusted, OR converted to RR.

risk of hospitalization, 35.3% lower, RR 0.65, p < 0.001, treatment 523 of 7,295 (7.2%), control 2,382 of 21,464 (11.1%), NNT 25, adjusted, OR converted to RR.

Mokhtari et al., 4/6/2021, retrospective, Iran, Middle East, peer-reviewed, 11 authors, dosage 400mg bid day 1, 200mg bid days 2-5.

Safety of treatment with chloroquine and hydroxychloroquine: A ten-year systematic review and meta-analysis

Edington et al., European Journal of Internal Medicine, doi:10.1016/j.ejim.2021.03.028

Safety analysis of CQ and HCQ covering 46 RCTs with 23,132 patients, showing no mortality attributed to CQ/HCQ. Authors conclude that the data reinforces that CQ and HCQ have a good safety profile though caution is advised when using higher than usual doses in hospitalized COVID-19 patients.

Edington et al., 4/5/2021, peer-reviewed, 3 authors.

Clinical Efficacy of Hydroxychloroquine in Patients with COVID-19: Findings from an Observational Comparative Study in Saudi Arabia

Alghamdi et al., Antibiotics, doi:10.3390/antibiotics10040365

Retrospective 775 hospitalized patients in Saudi Arabia showing no significant difference. There was no adjustment for severity or comorbidities. Confounding by indication is likely.

risk of death, 6.9% higher, RR 1.07, p = 0.88, treatment 44 of 568 (7.7%), control 15 of 207 (7.2%).

Excluded in after exclusion results of meta analysis: confounding by indication is likely and adjustments do not consider COVID-19 severity at baseline.

Alghamdi et al., 3/31/2021, retrospective, Saudi Arabia, Middle East, peer-reviewed, 10 authors.

Safety of hydroxychloroquine in healthcare workers for COVID-19 prophylaxis

Faruqui et al., Indian J. Med. Res., doi:10.4103/ijmr.IJMR_2294_20

Retrospective 1303 health care workers finding that HCQ prophylaxis was well tolerated. 20% reported an adverse event, mostly gastrointestinal. 1.5% received treatment for adverse effects, with none requiring hospitalization.

Faruqui et al., 3/26/2021, peer-reviewed, 24 authors.

Risk factors and frequency of COVID-19 among healthcare workers at a tertiary care centre in India: a case–control study

Dev et al., Transactions of The Royal Society of Tropical Medicine and Hygiene, doi:10.1093/trstmh/trab047

Retrospective case control study of 3,100 healthcare workers in India showing lower cases with HCQ prophylaxis, and an inverse association between the number of HCQ doses taken and the risk of COVID-19 cases. Low risk population with no mortality and no severe cases.

risk of case, 26.0% lower, RR 0.74, p = 0.003, treatment 260, control 499, any number of HCQ doses vs. no HCQ prophylaxis.

Dev et al., 3/24/2021, retrospective, India, South Asia, peer-reviewed, 5 authors.

Clinical Characteristics and Outcomes of Hospitalized COVID-19 Patients in a MERS-CoV Referral Hospital during the Peak of the Pandemic

Barry et al., International Journal of Infectious Diseases, doi:10.1016/j.ijid.2021.03.058

605 hospitalized patients in Saudi Arabia showing no mortality with HCQ (only 6 patients received HCQ).

risk of death, 98.9% lower, RR 0.01, p = 0.60, treatment 0 of 6 (0.0%), control 91 of 599 (15.2%), NNT 6.6, relative risk is not 0 because of continuity correction due to zero events.

Barry et al., 3/23/2021, retrospective, Saudi Arabia, Middle East, peer-reviewed, 14 authors.

COVID-19 Evidence Accelerator: A parallel analysis to describe the use of Hydroxychloroquine with or without Azithromycin among hospitalized COVID-19 patients

Stewart et al., PLoS ONE, doi:10.1371/journal.pone.0248128

Collection of seven retrospective database analyses in the USA, showing higher mortality with treatment (not statistically significant).

Results contradict strong evidence from the RECOVERY/SOLIDARITY trials, suggesting substantial confounding by indication.

Time based confounding is very likely because HCQ became highly controversial and usage dramatically declined over the time covered, while overall treatment protocols during this period improved dramatically, i.e., more control patients likely come later in the period when treatment protocols were greatly improved.

This study includes anyone PCR+ during or prior to their visit, and anyone with ICD-10 COVID-19 codes which includes asymptomatic PCR+ patients, therefore some patients in the control groups may be asymptomatic with regards to SARS-CoV-2, but in the hospital for another reason.

Authors do not mention the possibility of any of these likely confounding factors.

risk of death, 18.0% higher, RR 1.18, p = 0.27, treatment 90 of 429 (21.0%), control 141 of 737 (19.1%), adjusted, VA, HCQ+AZ.

risk of death, 1.0% lower, RR 0.99, p = 0.95, treatment 66 of 578 (11.4%), control 188 of 1,243 (15.1%), adjusted, TriNetX, HCQ+AZ.

risk of death, 129.9% higher, RR 2.30, p < 0.001, treatment 32 of 108 (29.6%), control 33 of 256 (12.9%), Synapse, HCQ+AZ.

risk of death, 9.0% higher, RR 1.09, p = 0.65, treatment 212 of 1,157 (18.3%), control 203 of 1,101 (18.4%), NNT 873, adjusted, Health Catalyst, HCQ+AZ.

risk of death, 90.0% higher, RR 1.90, p = 0.09, treatment 46 of 208 (22.1%), control 47 of 1,334 (3.5%), adjusted, Dascena, HCQ+AZ.

risk of death, 16.0% higher, RR 1.16, p = 0.26, treatment 428 of 1,711 (25.0%), control 123 of 688 (17.9%), adjusted, COTA/HMH, HCQ+AZ.

risk of mechanical ventilation, 29.0% higher, RR 1.29, p = 0.09, treatment 48 of 305 (15.7%), control 95 of 1,302 (7.3%), adjusted, Aetion, HCQ.

Excluded in after exclusion results of meta analysis: substantial unadjusted confounding by indication likely, substantial confounding by time likely due to declining usage over the early stages of the pandemic when overall treatment protocols improved dramatically, includes PCR+ patients that may be asymptomatic for COVID-19 but in hospital for other reasons.

Stewart et al., 3/17/2021, retrospective, USA, North America, peer-reviewed, 37 authors.

Structural basis of anti-SARS-CoV-2 activity of hydroxychloroquine: specific binding to NTD/CTD and disruption of LLPS of N protein

Dang et al., bioRxiv, doi:10.1101/2021.03.16.435741 (Preprint) (In Vitro)

Microscopy/spectroscopy study showing that HCQ binds to both N-terminal domain and C-terminal domain of SARS-CoV-2 nucleocapsid protein to inhibit
their interactions with nucleic acids and disrupt NA-induced liquid-liquid phase separation essential for the viral life cycle including the package of gRNA and N protein into new virions. These results suggest that HCQ may achieve its
anti-SARS-CoV-2 activity by interfering in several key steps of the viral life cycle.

Dang et al., 3/17/2021, preprint, 2 authors.

In Vitro studies are an important part of preclinical research, however results may be very different in vivo.

Outcome of Different Therapeutic Interventions in Mild COVID-19 Patients in a Single OPD Clinic of West Bengal: A Retrospective study

Roy et al., medRxiv, doi:10.1101/2021.03.08.21252883 (Preprint)

Retrospective database analysis of 56 mild COVID-19 patients, all treated with vitamin C, vitamin D, and zinc, comparing ivermectin + doxycycline (n=14), AZ (n=13), HCQ (n=14), and SOC (n=15), finding that all groups recover quickly, and there was no significant difference between the groups.

relative time to clinical response of wellbeing, 2.4% lower, relative time 0.98, p = 0.96, treatment 14, control 15, primary outcome.

Excluded in after exclusion results of meta analysis: no serious outcomes reported and fast recovery in treatment and control groups, there is little room for a treatment to improve results.

Roy et al., 3/12/2021, retrospective, database analysis, India, South Asia, preprint, 5 authors, dosage not specified.

Incidence of COVID-19 in patients exposed to chloroquine and hydroxychloroquine: results from a population-based prospective cohort in Catalonia, Spain, 2020

Vivanco-Hidalgo et al., Eurosurveillance, doi:/10.2807/1560-7917.ES.2021.26.9.2001202

Retrospective database analysis of chronic HCQ users and matched control patients, failing to match or adjust for the very different baseline risk for systemic autoimmune disease patients. Other research shows that the risk of COVID-19 for systemic autoimmune disease patients is much higher overall, Ferri et al. show OR 4.42, p<0.001 [Ferri].

1. Ferri at al., Clinical Rheumatology, doi:0.1007/s10067-020-05334-7, COVID-19 and rheumatic autoimmune systemic diseases: report of a large Italian patients series, https://link.springer.com/article/10.1007/s10067-020-05334-7.

risk of hospitalization, 46.0% higher, RR 1.46, p = 0.10, treatment 40 of 6,746 (0.6%), control 50 of 13,492 (0.4%), adjusted.

risk of case, 8.0% higher, RR 1.08, p = 0.50, treatment 97 of 6,746 (1.4%), control 183 of 13,492 (1.4%), adjusted.

Excluded in after exclusion results of meta analysis: not fully adjusting for the different baseline risk of systemic autoimmune patients.

Vivanco-Hidalgo et al., 3/9/2021, retrospective, Spain, Europe, peer-reviewed, 8 authors.

Absent or insufficient anti-SARS-CoV-2 S antibodies at ICU admission are associated to higher viral loads in plasma, antigenemia and mortality in COVID-19 patients

Martin-Vicente et al., medRxiv, doi:10.1101/2021.03.08.21253121 (Preprint)

Retrospective 92 ICU patients with almost all treated with HCQ and only one non-HCQ treated patient that died, showing unadjusted non-statistically significant lower mortality with treatment.

risk of death, 59.3% lower, RR 0.41, p = 0.41, treatment 37 of 91 (40.7%), control 1 of 1 (100.0%), NNT 1.7.

Excluded in after exclusion results of meta analysis: unadjusted results with no group details, treatment or control group size extremely small.

Martin-Vicente et al., 3/8/2021, retrospective, Spain, Europe, preprint, 38 authors.

Clinical Features and Prognostic Factors of 245 Portuguese Patients Hospitalized With COVID-19

Salvador et al., Cureus, doi:10.7759/cureus.13687

Prospective study of 245 hospitalized patients, 121 treated with HCQ, showing lower (non-statistically significant) mortality and higher ventilation at 30 days. Confounding by indication is likely.

risk of death, 32.9% lower, RR 0.67, p = 0.10, treatment 28 of 121 (23.1%), control 58 of 124 (46.8%), NNT 4.2, OR converted to RR, multivariate.

risk of mechanical ventilation, 447.8% higher, RR 5.48, p = 0.003, treatment 32 of 121 (26.4%), control 12 of 124 (9.7%), OR converted to RR, multivariate.

risk of death/intubation, 16.7% lower, RR 0.83, p = 0.21, treatment 51 of 121 (42.1%), control 63 of 124 (50.8%), NNT 12, OR converted to RR, univariate.

Salvador et al., 3/4/2021, prospective, Portugal, Europe, peer-reviewed, 10 authors.

Failure of chronic hydroxychloroquine in preventing severe complications of COVID-19 in patients with rheumatic diseases

Pham et al., Rheumatology Advances in Practice, 10.1093/rap/rkab014

Tiny retrospective database analysis of hospitalized COVID-19 patients with rheumatologic disease containing 14 chronic HCQ and 28 control patients. Patients are very poorly matched. Bias against HCQ is clear in the abstract which mentions differences favoring HCQ but ignores those favoring control (large differences in ethnicity, rheumatic conditions, hypertension, coronary artery disease, solid organ transplant recipients, immunosuppresive drugs). 61% of control patients also received HCQ. Adherence for chronic HCQ patients was not examined. Despite the very large differences between the groups, no adjustments are made. The study claims that HCQ did not prevent severe cases, but the study is among hospitalized patients, i.e., they already have cases severe enough for hospitalization - this study can not identify a protective effect of HCQ that reduces the probability of disease severe enough for hospitalization.

risk of death, 19.7% lower, RR 0.80, p = 0.77, treatment 2 of 14 (14.3%), control 5 of 28 (17.9%), NNT 28, OR converted to RR, univariate.

risk of ICU admission, 35.5% higher, RR 1.35, p = 0.61, treatment 4 of 14 (28.6%), control 6 of 28 (21.4%), OR converted to RR, univariate.

Pham et al., 3/2/2021, retrospective, USA, North America, peer-reviewed, 5 authors.

Chloroquine nasal drops in asymptomatic & mild COVID-19: An exploratory randomized clinical trial

Thakar et al., Indian J. Med. Res., doi:10.4103/ijmr.IJMR_3665_20

Small RCT for CQ nasal drops suggesting efficacy in preventing infection, while no significant difference was seen for patients that already had mild COVID-19.

Thakar et al., 2/28/2021, peer-reviewed, 11 authors.

A Preventive Study on Hydroxychloroquine Prophylaxis against COVID-19 in Health Care Workers at a Tertiary Care Center in North India

Bhandari et al., International Journal of Medicine and Public Health, doi:10.5530/ijmedph.2021.1.4

Retrospective 4,239 healthcare workers using HCQ prophylaxis showing no mortality, 8 mild symptomatic cases, and 85 asymptomatic cases, with the cases occuring mostly in the first week.

Bhandari et al., 2/28/2021, India, South Asia, peer-reviewed, 10 authors.

Hydroxychloroquine for SARS-CoV-2 positive patients quarantined at home: The first interim analysis of a remotely conducted randomized clinical trial

Amaravadi et al., medRxiv, doi:10.1101/2021.02.22.21252228 (Preprint)

Tiny early-terminated 34 patient RCT for outpatient treatment showing faster recovery with treatment (not statistically significant). All patients recovered (3 control patients recovered after crossover to the treatment arm). There was no mortality and only one hospitalization on day 0 before treatment. There were no severe adverse events.

risk of not reaching lowest symptom score at day 7 mid-recovery, 60.0% lower, RR 0.40, p = 0.13, treatment 3 of 15 (20.0%), control 6 of 12 (50.0%), NNT 3.3.

relative time to first occurrence of lowest symptom score, 42.9% lower, relative time 0.57, p = 0.21, treatment 15, control 12.

relative time to release from quarantine, 27.3% lower, relative time 0.73, p = 0.28, treatment 16, control 13.

Amaravadi et al., 2/26/2021, Double Blind Randomized Controlled Trial, USA, North America, preprint, 20 authors, dosage 400mg bid days 1-14.

Hydroxychloroquine plus azithromycin and early hospital admission are beneficial in COVID-19 patients: Turkish experience with real-life data

Tanriverdi et al., Turkish Journal of Medical Sciences, doi:doi:10.3906/sag-2005-82

Retrospective 83 hospitalized patients in Turkey confirming that earlier treatment is better, and showing that the addition of AZ to HCQ reduced hospitalization time.

Tanriverdi et al., 2/26/2021, peer-reviewed, 8 authors.

The Need for Early Management in Patients With COVID-19

Giraud-Gatineau et al., Research Square, doi:rs.3.rs-251817/v1 (Preprint)

Review of early treatment of COVID-19 at IHU Méditerranée Infection in France, including HCQ+AZ treatment, comparing outcomes to those for all of France. Age-standardized mortality was lower with early treatment for all periods of the epidemic. Authors recommend early treatment for all age groups.

Giraud-Gatineau et al., 2/26/2021, preprint, 9 authors.

Efficacy and Safety of Ivermectin and Hydroxychloroquine in Patients with Severe COVID-19: A Randomized Controlled Trial

Beltran Gonzalez et al., Infectious Disease Reports, doi:10.3390/idr14020020 (preprint 2/23/2021)

RCT late stage severe condition (93% SOFA ≥ 2, 96% APACHE ≥ 8) high comorbidity hospitalized patients in Mexico with 33 HCQ and 37 control patients not finding significant differences. NCT04391127.

risk of death, 62.6% lower, RR 0.37, p = 0.27, treatment 2 of 33 (6.1%), control 6 of 37 (16.2%), NNT 9.8.

risk of respiratory deterioration or death, 25.3% lower, RR 0.75, p = 0.57, treatment 6 of 33 (18.2%), control 9 of 37 (24.3%), NNT 16.

risk of no hospital discharge, 12.1% higher, RR 1.12, p = 1.00, treatment 3 of 33 (9.1%), control 3 of 37 (8.1%).

Beltran Gonzalez et al., 2/23/2021, Double Blind Randomized Controlled Trial, Mexico, North America, peer-reviewed, mean age 53.8, 13 authors, average treatment delay 7.0 days, trial NCT04391127.

Recent Hydroxychloroquine Use Is Not Significantly Associated with Positive PCR Results for SARS-CoV-2: A Nationwide Observational Study in South Korea

Bae et al., Viruses 2021, doi:10.3390/v13020329

Retrospective database analysis of prior HCQ usage in South Korea, showing non-statistically significantly lower mortality and cases with treatment.

risk of case, 30.3% lower, RR 0.70, p = 0.18, treatment 16 of 743 (2.2%), control 91 of 2,698 (3.4%), NNT 82, OR converted to RR, PSM.

risk of case, 19.5% lower, RR 0.81, p = 0.50, treatment 16 of 743 (2.2%), control 91 of 2,698 (3.4%), OR converted to RR, PSM, adjusted for region.

risk of case, 30.3% lower, RR 0.70, p = 0.30, treatment 16 of 743 (2.2%), control 91 of 2,698 (3.4%), NNT 82, OR converted to RR, PSM, adjusted for immunosuppresant use.

risk of case, 40.2% lower, RR 0.60, p = 0.09, OR converted to RR, PSM, HCQ >= 6 months.

Bae et al., 2/20/2021, retrospective, propensity score matching, South Korea, Asia, peer-reviewed, 8 authors.

Hydroxychloroquine with azithromycin in patients hospitalized for mild and moderate COVID-19

Lamback et al., The Brazilian Journal of Infectious Diseases, doi:10.1016/j.bjid.2021.101549

Retrospective 193 hospitalized patients in Brazil not finding a significant difference with HCQ.

The control group was composed of patients refusing HCQ or with contraindications. Time based confounding is very likely because HCQ became more controversial in Brazil over the time covered (Mar - Jun 2020), while overall treatment protocols during this period improved dramatically, i.e., more control patients (those refusing HCQ) likely come later in the period when treatment protocols were greatly improved.

The paper does not mention the word "confounding" or make any adjustments.

risk of death, 8.9% lower, RR 0.91, p = 0.83, treatment 11 of 101 (10.9%), control 11 of 92 (12.0%), NNT 94.

risk of ICU admission, 19.9% higher, RR 1.20, p = 0.61, treatment 25 of 101 (24.8%), control 19 of 92 (20.7%).

hospitalization time, 12.5% lower, relative time 0.88, treatment 101, control 92.

Excluded in after exclusion results of meta analysis: substantial confounding by time likely due to declining usage over the early stages of the pandemic when overall treatment protocols improved dramatically.

Lamback et al., 2/19/2021, retrospective, Brazil, South America, peer-reviewed, 10 authors.

Impact of hydroxychloroquine on disease progression and ICU admissions in patients with SARS-CoV-2 infection

Awad et al., American Journal of Health-System Pharmacy, doi:10.1093/ajhp/zxab056

This paper has inconsistent values - the number of treatment and control patients differs in the text and Table 1, we have used treatment 188 and control 148. Retrospective 336 hospitalized patients in the USA showing higher mortality, ICU admission, and intubation with treatment. Confounding by indication is likely. Time varying confounding is also likely due to declining usage over the early period when overall treatment protocols were also improving dramatically. Authors and reviewers appear to be unfamiliar with either of these.

risk of death, 19.1% higher, RR 1.19, p = 0.60, treatment 56 of 188 (29.8%), control 37 of 148 (25.0%).

risk of mechanical ventilation, 460.7% higher, RR 5.61, p < 0.001, treatment 64 of 188 (34.0%), control 9 of 148 (6.1%), adjusted, OR converted to RR.

risk of ICU admission, 463.4% higher, RR 5.63, p < 0.001, treatment 67 of 188 (35.6%), control 9 of 148 (6.1%), adjusted, OR converted to RR.

Excluded in after exclusion results of meta analysis: substantial confounding by time likely due to declining usage over the early stages of the pandemic when overall treatment protocols improved dramatically, substantial unadjusted confounding by indication likely.

Awad et al., 2/18/2021, retrospective, USA, North America, peer-reviewed, 4 authors.

Seroprevalence of IgG against SARS-CoV-2 and its determinants among healthcare workers of a COVID-19 dedicated hospital of India

Mahto et al., American Journal of Blood Research, 11:1

Retrospective 689 healthcare workers in India, showing no significant difference in IgG positivity with HCQ prophylaxis in unadjusted results.

risk of IgG positive, 26.9% lower, RR 0.73, p = 0.38, treatment 9 of 89 (10.1%), control 84 of 600 (14.0%), NNT 26, unadjusted, OR converted to RR.

Excluded in after exclusion results of meta analysis: unadjusted results with no group details.

Mahto et al., 2/15/2021, retrospective, India, South Asia, peer-reviewed, 6 authors.

Early Lopinavir/ritonavir does not reduce mortality in COVID-19 patients: results of a large multicenter study

Lora-Tamayo et al., J. Infection, doi:10.1016/j.jinf.2021.02.011

Lopinavir/ritonavir retrospective study also showing univariate results for HCQ, with significantly lower mortality.

risk of death, 50.5% lower, RR 0.50, p < 0.001, treatment 7,192, control 1,361, OR converted to RR, univariate, control prevalence approximated with overall prevalence.

Lora-Tamayo et al., 2/11/2021, retrospective, Spain, Europe, peer-reviewed, 10 authors.

The Use of Antiviral Agents against SARS-CoV-2: Ineffective or Time and Age Dependent Result? A Retrospective, Observational Study among COVID-19 Older Adults

Desai et al., J. Clinical Medicine, doi:10.3390/jcm10040686

Retrospective 143 COVID-19 hospitalized patients >65yo, showing adjusted OR for antiviral treatment starting within 6 days of 0.44 [0.2-0.9], p = 0.02, compared to treatment started later.

Desai et al., 2/10/2021, peer-reviewed, 9 authors.

Outcomes Related to COVID-19 Treated With Hydroxychloroquine Among In-patients With Symptomatic Disease (ORCHID)

Thompson et al., NCT04332991 (Preprint)

Late stage (65% on oxygen at baseline) low-dose RCT, not showing significant differences with treatment.

risk of death, 6.2% higher, RR 1.06, p = 0.85, treatment 25 of 241 (10.4%), control 25 of 236 (10.6%), NNT 455, adjusted, OR converted to RR, day 28.

risk of death, 51.0% higher, RR 1.51, p = 0.28, treatment 18 of 241 (7.5%), control 14 of 236 (5.9%), adjusted, OR converted to RR, day 14.

risk of 7-point scale, 3.1% higher, OR 1.03, p = 0.87, treatment 241, control 236, day 28, RR approximated with OR.

risk of 7-point scale, 2.0% lower, OR 0.98, p = 0.91, treatment 241, control 236, day 14, RR approximated with OR.

Thompson et al., 2/9/2021, Double Blind Randomized Controlled Trial, USA, North America, preprint, 1 author.

Revisiting a Meta-analysis Shows that Hydroxychloroquine with Azithromycin may be Efficient in Covid-19 patients

Lounnas e al., Archives of Microbiology & Immunology, doi: (meta analysis)

Analysis of the Fiolet meta analysis and correction of bias evaluation, showing HCQ RR 0.45 [0.31-0.59], and HCQ+AZ RR 0.34 [0.06-0.61].

Lounnas et al., 2/9/2021, peer-reviewed, 4 authors.

A Randomized, Double-Blind, Multicenter Clinical Study Comparing the Efficacy and Safety of a Drug Combination of Lopinavir/Ritonavir-Azithromycin, Lopinavir/Ritonavir-Doxycycline, and Azithromycin-Hydroxychloroquine for Patients Diagnosed with Mild to Moderate COVID-19 Infections

Purwati et al., Biochemistry Research International, doi:10.1155/2021/6685921

RCT 754 patients comparing HCQ+AZ along with other treatment groups using lopinavir/ritonavir and doxycycline to a control group taking AZ, finding significantly faster viral clearance with all treatment groups. (The labels in Figure 2 appear to be reversed).

risk of no viral clearance, 66.3% lower, RR 0.34, p < 0.001, treatment 38 of 121 (31.4%), control 111 of 119 (93.3%), NNT 1.6, day 7.

Purwati et al., 2/9/2021, Double Blind Randomized Controlled Trial, Indonesia, South Asia, peer-reviewed, 12 authors.

Risk Factors for Infection and Health Impacts of the COVID-19 Pandemic in People with Autoimmune Diseases

Fitzgerald et al., medRxiv, doi:10.1101/2021.02.03.21251069 (Preprint)

Retrospective 4666 people with autoimmune or inflammatory conditions, showing HCQ adjusted risk of COVID-19 OR 0.91 [0.68-1.23]. Results are not adjusted for the significantly different risk of COVID-19 depending on the type and severity of autoimmune or inflammatory condition.

risk of case, 8.5% lower, RR 0.91, p = 0.54, treatment 65 of 1,072 (6.1%), control 200 of 3,594 (5.6%), adjusted, OR converted to RR.

Excluded in after exclusion results of meta analysis: not fully adjusting for the baseline risk differences within systemic autoimmune patients.

Fitzgerald et al., 2/5/2021, retrospective, USA, North America, preprint, 34 authors.

Hydroxychloroquine for the treatment of severe respiratory infection by COVID-19: a randomized controlled trial

Hernandez-Cardenas et al., medRxiv, doi:10.1101/2021.02.01.21250371 (Preprint)

Very late stage RCT with 214 patients, mean SpO₂ 65%, 162 on mechanical ventilation, showing no significant difference in mortality.

Patients not intubated at baseline show greater improvement, HR 0.43 [0.09-2.03].

Table 4 shows different results to the abstract - table 4 adjusted HR 0.80 [0.51-1.23], abstract HR 0.88 [0.51-1.53]. There was no significant difference in severe adverse events.

risk of death, 12.0% lower, RR 0.88, p = 0.66, treatment 106, control 108.

risk of death, 57.0% lower, RR 0.43, p = 0.29, subgroup not intubated at baseline.

Hernandez-Cardenas et al., 2/5/2021, Randomized Controlled Trial, Mexico, North America, preprint, 6 authors, average treatment delay 7.4 days.

Factors associated with the occurrence of acute respiratory distress and death in patients with COVID-19 in Burkina Faso

Ouedraogo et al., Revue des Maladies Respiratoires, doi:10.1016/j.rmr.2021.02.001

Retrospective 456 patients in Burkina Faso showing lower risk of ARDS (p=0.001) and mortality (p=0.38) with HCQ.

risk of death, 33.0% lower, HR 0.67, p = 0.38, treatment 397, control 59, multivariate.

risk of ARDS, 68.0% lower, OR 0.32, p = 0.001, treatment 397, control 59, multivariate, RR approximated with OR.

Ouedraogo et al., 2/5/2021, retrospective, Burkina Faso, Africa, peer-reviewed, 14 authors.

Early Multidrug Outpatient Treatment of SARS-CoV-2 Infection (COVID-19) and Reduced Mortality Among Nursing Home Residents

Alexander et al., medRxiv, doi:10.1101/2021.01.28.21250706 (Review) (Preprint)

Review of studies on treatment of COVID-19 for nursing home residents, concluding that there is a large >60% mortality risk reduction associated with multidrug treatment using two or more intracellular anti-infectives (HCQ and either AZM or DOXY) combined with other agents including corticosteroids, anti-thrombotics, and nutraceuticals. Authors note there is also recent focus on ivermectin and favorable evidence for bromhexine.

Alexander et al., 2/1/2021, preprint, 11 authors.

COVID-19: A Single-Center ICU Experience of the First Wave in the Philippines

Ubaldo et al., Critical Care Research and Practice, 10.1155/2021/7510306

Retrospective ICU patients in the Philippines showing unadjusted HCQ RR 0.82, p = 0.64.

risk of death, 18.4% lower, RR 0.82, p = 0.64, treatment 17 of 25 (68.0%), control 5 of 6 (83.3%), NNT 6.5, COVID-19 positive patients.

Excluded in after exclusion results of meta analysis: substantial unadjusted confounding by indication likely, very late stage, ICU patients, unadjusted results with no group details.

Ubaldo et al., 2/1/2021, retrospective, Philippines, Asia, peer-reviewed, 3 authors.

Prophylactic effects of hydroxychloroquine on the incidence of COVID-19 in patients with rheumatic arthritis: an observational cohort study

Naderi et al., Immunopathologia Persa, doi:10.34172/ipp.2021.29 (Preprint)

Prospective observational study of 215 RA patients treated with HCQ showing 9 cases, 1 hospitalization (without ICU/intubation), and no mortality.

Naderi et al., 1/31/2021, preprint, 7 authors.

Clinical and pharmacological data in COVID-19 hospitalized nonagenarian patients

Roig et al., Revista Espanola de Quimioterapia, doi:10.37201/req/130.2020

Retrospective 79 hospitalized nonagenarian patients showing unadjusted HCQ mortality RR 0.84, p = 0.76.

risk of death, 15.6% lower, RR 0.84, p = 0.76, treatment 33 of 67 (49.3%), control 7 of 12 (58.3%), NNT 11.

Excluded in after exclusion results of meta analysis: unadjusted results with no group details.

Roig et al., 1/31/2021, retrospective, Spain, Europe, peer-reviewed, 6 authors.

Disentangling the Association of Hydroxychloroquine Treatment with Mortality in Covid-19 Hospitalized Patients through Hierarchical Clustering

Di Castelnuovo et al., Journal of Healthcare Engineering, doi:10.1155/2021/5556207 (preprint 1/29/2021)

Retrospective 4,396 hospitalized patients in Italy showing significantly lower mortality with HCQ treatment, and identifying greater efficacy for a subgroup of patients in clustering analysis.

risk of death, 40.0% lower, RR 0.60, p < 0.001, treatment 3,270, control 1,000, OR converted to RR, multivariate Cox proportional hazards model 4, control prevalence approximated with overall prevalence.

Di Castelnuovo et al., 1/29/2021, retrospective, Italy, Europe, peer-reviewed, 112 authors.

Effet d’un traitement par hydroxychloroquine prescrit comme traitement de fond de rhumatismes inflammatoires chroniques ou maladies auto-immunes systémiques sur les tests diagnostiques et l’évolution de l’infection à SARS CoV-2: étude de 871 patients

Trefond et al., Revue du Rhumatisme, doi:10.1016/j.rhum.2021.09.004 (preprint 1/27/2021)

Retrospective 71 chronic HCQ patients compared with 191 matched controls, analyzing only those with a highly suspected or confirmed diagnosis of COVID-19. No significant difference was found in outcomes, however matching failed with extreme confounding - 77.5% of HCQ patients with systemic autoimmune diseases vs. 21.5% of control patients.

Other research shows that the risk of COVID-19 for systemic autoimmune disease patients is much higher overall, Ferri et al. show OR 4.42, p<0.001 [Ferri].

1. Ferri at al., Clinical Rheumatology, doi:0.1007/s10067-020-05334-7, COVID-19 and rheumatic autoimmune systemic diseases: report of a large Italian patients series, https://link.springer.com/article/10.1007/s10067-020-05334-7.

risk of death, 16.6% higher, RR 1.17, p = 0.80, treatment 4 of 68 (5.9%), control 12 of 183 (6.6%), adjusted, OR converted to RR.

risk of death/ICU, 78.2% higher, RR 1.78, p = 0.21, treatment 8 of 71 (11.3%), control 18 of 191 (9.4%), adjusted, OR converted to RR.

risk of hospitalization, 44.9% higher, RR 1.45, p = 0.12, treatment 24 of 71 (33.8%), control 53 of 191 (27.7%), adjusted, OR converted to RR.

Excluded in after exclusion results of meta analysis: not fully adjusting for the different baseline risk of systemic autoimmune patients, significant unadjusted confounding possible, excessive unadjusted differences between groups.

Trefond et al., 1/27/2021, retrospective, France, Europe, peer-reviewed, 21 authors.

Hydroxychloroquine and azithromycin: As a double edge sword for COVID-19?

Eftekhar et al., medRxiv, doi:10.1101/2021.01.16.21249941 (Preprint)

Retrospective 172 hospitalized patients, 83% treated and HCQ+AZ and 17% with HCQ, not finding a significant difference in QTc prolongation, but recommending careful monitoring for the use of HCQ+AZ; especially in males, patients with high-risk Tisdale score, and in patients who have baseline QTc interval ≥ 450 milliseconds.

Eftekhar et al., 1/26/2021, preprint, 6 authors.

Efficacy of favipiravir in COVID-19 treatment: a multi-center randomized study

Dabbous et al., Archives of Virology, doi:10.1007/s00705-021-04956-9

This study was retracted.

Dabbous et al., 1/25/2021, peer-reviewed, 10 authors.

Molecular Docking Identification for the efficacy of Some Zinc Complexes with Chloroquine and Hydroxychloroquine against Main Protease of COVID-19

Hussein et al., Journal of Molecular Structure, doi:10.1016/j.molstruc.2021.129979

Molecular dynamics analysis recommending Zn (CQ) Cl2(H2O) and Zn (HCQ) Cl2(H2O) as potential inhibitors for COVID-19 M^pro. Zn (HCQ) Cl2(H2O) exhibited a strong binding to the main protease receptor, forming eight hydrogen bonds.

Hussein et al., 1/25/2021, peer-reviewed, 2 authors.

In Silico studies are an important part of preclinical research, however results may be very different in vivo.

Nebulized Hydroxychloroquine for COVID-19 Treatment: 80x Improvement in Breathing

Zelenko, Z., Preprint (Preprint)

Report on the use of nebulized HCQ showing much more rapid improvement compared to tablets, with 95% of patients experiencing improved breathing within 1 hour. Author notes that the effectiveness of HCQ is time and dose dependent, with a primary issue being the time it takes for a therapeutic dosage to reach the lungs, and that treatment with tablets may take an average of 80 hours to achieve significant clinical improvement.

Author notes that it may take 3-7 days to achieve optimal alveolar concentrations with tablets, whereas nebulized HCQ administered as microdroplets directly to the lungs achieves optimal alveolar concentration in approximately one hour and is associated with faster clinical improvement, reduction in pulmonary complications, and a reduction in medical costs.

Zelenko et al., 1/24/2021, preprint, 1 author.

Incidence of COVID-19 in patients under chronic treatment with hydroxychloroquine

Cifuentes et al., Medicina Clínica (English Edition), doi:10.1016/j.medcle.2020.10.012

Retrospective 3,817 chronic HCQ patients showing 4.4% COVID-19 positive rate, 1.3% severe. There is no comparison with a control group. Authors note that there was a 3.6% incidence among 2,032,863 patients in one of the regions (Castilla La Mancha), however they provide no information on this group - it is expected that the mostly systemic autoimmune disease patients in the treatment group are older on average. Additonally, other research shows that the risk of COVID-19 for systemic autoimmune disease patients is much higher overall, Ferri et al. show OR 4.42, p<0.001 [Ferri].

1. Ferri at al., Clinical Rheumatology, doi:0.1007/s10067-020-05334-7, COVID-19 and rheumatic autoimmune systemic diseases: report of a large Italian patients series, https://link.springer.com/article/10.1007/s10067-020-05334-7.

Cifuentes et al., 1/23/2021, peer-reviewed, 18 authors.

Evaluation of the efficacy and safety of hydroxychloroquine in comparison with chloroquine in moderate and severe patients with COVID-19

Li et al., Science China Life Sciences, doi:10.1007/s11427-020-1871-4

Small RCT comparing HCQ and CQ in China with 88 very late stage (17.6 days from onset to hospitalization and ~10 days to randomization) patients. The primary clinical outcomes (TTCR and TTCI) were not significantly different. Authors note that HCQ may have more promising efficacy in immune system modulation, indicated by ferritin reduction in the moderate cases and improvement of CT scores and lymphocyte counts in the severe cases. HCQ and CQ were well tolerated.

Authors also compare RCT patients to a matched sample of non-RCT patients in the same hospital, showing shorter time to discharge with CQ/HCQ, but not statistically significant due to the small size.

risk of no hospital discharge, 50.0% lower, HR 0.50, p = 0.09, treatment 14, control 14, RCT patients vs. matched sample of non-treated patients.

Li et al., 1/18/2021, retrospective, China, Asia, peer-reviewed, 21 authors.

Prevalence of COVID-19 in patients with rheumatoid arthritis (RA) already treated with hydroxychloroquine (HCQ) compared with HCQ-naive patients with RA: a multicentre cross-sectional study

Khoubnasabjafari et al., Postgraduate Medical Journal, doi:10.1136/postgradmedj-2020-139561

Survey analysis of 1,858 RA patients in Iran, showing no significant difference in cases with HCQ prophylaxis.

risk of case, 16.7% lower, RR 0.83, p = 0.59, treatment 34 of 1,436 (2.4%), control 12 of 422 (2.8%), NNT 210.

Khoubnasabjafari et al., 1/13/2021, retrospective, Iran, Middle East, peer-reviewed, 10 authors.

Treatment of COVID-19 patients with hydroxychloroquine or chloroquine: A retrospective analysis

Li et al., Research Square, doi:10.21203/rs.3.rs-119202/v1 (Preprint)

Small retrospective database analysis of 37 late stage patients hospitalized in an intensive care center in China, not finding a significant difference in viral shedding. Pateints were all in serious condition. There was only one death however the group is not specified. Confounding by indication is likely.

time to viral-, 40.0% higher, relative time 1.40, p = 0.06, treatment 18, control 19.

Li et al., 1/12/2021, retrospective, database analysis, China, Asia, preprint, 5 authors.

Chronic Hydroxychloroquine Therapy and COVID-19 Outcomes: A Retrospective Case-Control Analysis

Rangel et al., Journal of the American Academy of Dermatology, doi:10.1016/j.jaad.2020.10.098

Retrospective 50 COVID-19 patients that take chronic HCQ, compared to a matched sample of patients not taking chronic HCQ, showing lower mortality and ICU admission, and shorter hospitalization for HCQ patients, but not statistically significant due to the small number of events.

The actual benefit for HCQ could be much larger. The study does not address the risk of being sick enough to visit the hospital. HCQ users are likely systemic autoimmune disease patients and authors do not adjust for the very different baseline risk for these patients. Other research shows that the risk of COVID-19 for systemic autoimmune disease patients is much higher overall, Ferri et al. show OR 4.42, p<0.001 [Ferri].

1. Ferri at al., Clinical Rheumatology, doi:0.1007/s10067-020-05334-7, COVID-19 and rheumatic autoimmune systemic diseases: report of a large Italian patients series, https://link.springer.com/article/10.1007/s10067-020-05334-7.

risk of death, 25.1% lower, RR 0.75, p = 0.77, treatment 4 of 50 (8.0%), control 11 of 103 (10.7%), NNT 37, from all patients.

risk of hospitalization, 22.2% lower, RR 0.78, p = 0.29, treatment 17 of 50 (34.0%), control 45 of 103 (43.7%), NNT 10.

hospitalization time, 41.2% lower, relative time 0.59, p = 0.12, treatment 21, control 54.

Excluded in after exclusion results of meta analysis: not fully adjusting for the different baseline risk of systemic autoimmune patients.

Rangel et al., 1/10/2021, retrospective, USA, North America, peer-reviewed, 5 authors.

Epidemiological and Clinical Characteristics, and Virologic Features of COVID-19 Patients in Kazakhstan: a Nation-Wide, Retrospective, Cohort Study

Yegerov et al., medRxiv, doi:10.1101/2021.01.06.20249091 (Preprint)

Retrospective 1,072 hospitalized patients in Kazakhstan showing no mortality for HCQ treated patients, however only 23 patients received treatment - this result is not statistically significant.

risk of death, 95.3% lower, RR 0.05, p = 1.00, treatment 0 of 23 (0.0%), control 20 of 1,049 (1.9%), NNT 52, relative risk is not 0 because of continuity correction due to zero events.

Excluded in after exclusion results of meta analysis: unadjusted results with no group details.

Yegerov et al., 1/8/2021, retrospective, Kazakhstan, Asia, preprint, 8 authors, average treatment delay 1.0 days.

Inhibitory capacity of Chloroquine against SARS-COV-2 by effective binding with Angiotensin converting enzyme-2 receptor: An insight from molecular docking and MD-simulation studies

Baildya et al., Journal of Molecular Structure, doi:10.1016/j.molstruc.2021.129891

Molecular docking study of 16 drugs showing CQ had the highest binding affinity with ACE2, and molecular dynamics study of the docked CQ-ACE2 structure. Authors conclude that CQ binds reasonably strongly with ACE2 and the stable ACE2-CQ may prevent further binding of ACE2 with the SARS-CoV-2 spike protein.

Baildya et al., 1/7/2021, peer-reviewed, 3 authors.

In Silico studies are an important part of preclinical research, however results may be very different in vivo.

Quantum chemical studies on molecular structure, AIM, ELF, RDG and antiviral activities of hybrid hydroxychloroquine in the treatment of COVID-19: molecular docking and DFT calculations

Noureddine et al., Journal of King Saud University - Science, doi:10.1016/j.jksus.2020.101334

In silico analysis of hydroxychloroquine and hydroxychloroquine sulfate predicting that hydroxychloroquine sulfate is more stable and effective for COVID-19.

Noureddine et al., 1/6/2021, peer-reviewed, 5 authors.

In Silico studies are an important part of preclinical research, however results may be very different in vivo.

Safety profile of hydroxychloroquine and azithromycin combined treatment in COVID-19 patients

Gautret et al., International Journal of Antimicrobial Agents, doi:10.1016/j.ijantimicag.2020.106236

Report on the safety of HCQ+AZ with 3,737 COVID-19 patients. 138 had contraindications and treatment was discontinued in 12 cases due to QTc prolongation. There were no cases of torsade de pointe or sudden death.

Gautret et al., 1/4/2021, peer-reviewed, 4 authors.

Determinants of in-hospital mortality in COVID-19; a prospective cohort study from Pakistan

Sarfaraz et al., medRxiv, doi:10.1101/2020.12.28.20248920 (Preprint)

Retrospective 186 hospitalized patients in Pakistan showing unadjusted HCQ mortality RR 1.45, p = 0.07. Confounding by indication is likely.

risk of death, 45.0% higher, RR 1.45, p = 0.07, treatment 40 of 94 (42.6%), control 27 of 92 (29.3%).

Excluded in after exclusion results of meta analysis: substantial unadjusted confounding by indication likely, significant unadjusted confounding possible, unadjusted results with no group details.

Sarfaraz et al., 1/2/2021, retrospective, Pakistan, South Asia, preprint, 7 authors, average treatment delay 7.0 days.

Use of Hydroxychloroquine in Patients with COVID-19: A Retrospective Observational Study

Lotfy et al., Turk. Thorac. J., doi:10.5152/TurkThoracJ.2021.20180

Retrospective 202 patients in Saudi Arabia not showing significant differences with treatment. No information is provided on how patients were selected for treatment, there may be significant confounding by indication. Time varying confounding is also likely as HCQ became controversial during the period studied, therefore HCQ use was likely more frequent toward the beginning of the period, a time when overall treatment protocols were significantly worse.

risk of death, 24.8% higher, RR 1.25, p = 0.76, treatment 6 of 99 (6.1%), control 5 of 103 (4.9%).

risk of mechanical ventilation, 41.2% higher, RR 1.41, p = 0.34, treatment 19 of 99 (19.2%), control 14 of 103 (13.6%).

risk of ICU admission, 16.5% higher, RR 1.17, p = 0.53, treatment 28 of 99 (28.3%), control 25 of 103 (24.3%).

Excluded in after exclusion results of meta analysis: substantial confounding by time likely due to declining usage over the early stages of the pandemic when overall treatment protocols improved dramatically, substantial unadjusted confounding by indication likely.

Lotfy et al., 1/1/2021, retrospective, Saudi Arabia, Middle East, peer-reviewed, mean age 55.0, 3 authors.

No clinical benefit in mortality associated with hydroxychloroquine treatment in patients with COVID-19

Sands et al., International Journal of Infectious Diseases, doi:/10.1016/j.ijid.2020.12.060

Retrospective database analysis of 1,669 patients in the US showing OR 1.81, p = 0.01. Confounding by indication is likely.

COVID-19 was determined via PCR+ results, therefore authors include patients asymptomatic for COVID-19, but in the hospital for other reasons. While authors adjust for severity, the method used is very poor. 93.5% of patients are classified as "mild", which is patients with no documented care in a critical care unit within 8 hours of admission. Therefore almost all patients are in the same category, and those in a different category may be due to symptoms unrelated to COVID-19. Lower bias toward male patients in the control group also agrees with the hypothesis that the control group is made up of more people that were in hospital for another reason.

Since the analysis covers the initial period of the pandemic in the USA, it is likely that HCQ was used more often earlier in the analysis period when treatment protocols were considerably worse. It's unclear why the analysis only considers patients up to April 27, when the manuscript was submitted in October.

For other issues see [ijidonline.com].

1. ijidonline.com, https://www.ijidonline.com/article/S1201-9712(21)00165-X/pdf.

risk of death, 69.9% higher, RR 1.70, p = 0.01, treatment 101 of 973 (10.4%), control 56 of 696 (8.0%), OR converted to RR.

Excluded in after exclusion results of meta analysis: includes PCR+ patients that may be asymptomatic for COVID-19 but in hospital for other reasons, substantial unadjusted confounding by indication likely.

Sands et al., 1/1/2021, retrospective, database analysis, USA, North America, peer-reviewed, 10 authors.

A Retrospective Observational Study of Hypoxic COVID-19 Patients Treated with Immunomodulatory Drugs in a Tertiary Care Hospital

Mahale et al., Indian Journal of Critical Care Medicine, doi:10.5005/jp-journals-10071-23599

Retrospective 134 hospitalized COVID-19 patients in India, showing no significant difference with HCQ treatment in unadjusted results.

risk of death, 28.7% lower, RR 0.71, p = 0.36, treatment 25 of 102 (24.5%), control 11 of 32 (34.4%), NNT 10.

Excluded in after exclusion results of meta analysis: unadjusted results with no group details.

Mahale et al., 12/31/2020, retrospective, India, South Asia, peer-reviewed, 22 authors, study period 22 March, 2020 - 21 May, 2020.

A comprehensive review on the biological interest of quinoline and its derivatives

Matada et al., Bioorganic & Medicinal Chemistry, doi:10.1016/j.bmc.2020.115973 (Review)

Review of quinolone and derivatives, natural and drug sources, and biological activity.

Matada et al., 12/31/2020, peer-reviewed, 3 authors.

Corona Virus Disease-19 (COVID-19) in a Veterans Affairs Hospital at Suffolk County, Long Island, New York

Psevdos et al., Open Forum Infectious Diseases, doi:10.1093/ofid/ofaa439.721

Retrospective 67 hospitalized patients in the USA showing non-statistically significant unadjusted increased mortality with HCQ. Confounding by indication is likely.

Time varying confounding is likely. HCQ became controversial and was suspended during the end of the period studied, therefore HCQ use was likely more frequent toward the beginning of the study period, a time when overall treatment protocols were significantly worse.

risk of death, 63.5% higher, RR 1.63, p = 0.52, treatment 17 of 52 (32.7%), control 3 of 15 (20.0%).

Excluded in after exclusion results of meta analysis: unadjusted results with no group details, no treatment details, substantial confounding by time likely due to declining usage over the early stages of the pandemic when overall treatment protocols improved dramatically, substantial unadjusted confounding by indication likely.

Psevdos et al., 12/31/2020, retrospective, USA, North America, peer-reviewed, 3 authors.

Characteristics and outcomes of COVID-19 patients admitted to a regional health system in the southeast

Texeira et al., Open Forum Infectious Diseases, doi:10.1093/ofid/ofaa439.560

Retrospective 161 hospitalized patients in the USA showing non-statistically significant unadjusted increased mortality with HCQ. Confounding by indication is likely.

Time varying confounding is likely. HCQ became controversial and was suspended towards the end of the period studied, therefore HCQ use was likely more frequent toward the beginning of the study period, a time when overall treatment protocols were significantly worse.

risk of death, 79.3% higher, RR 1.79, p = 0.10, treatment 17 of 65 (26.2%), control 14 of 96 (14.6%).

Excluded in after exclusion results of meta analysis: unadjusted results with no group details, no treatment details, substantial confounding by time likely due to declining usage over the early stages of the pandemic when overall treatment protocols improved dramatically, substantial unadjusted confounding by indication likely.

Texeira et al., 12/31/2020, retrospective, USA, North America, peer-reviewed, 6 authors.

Early experimental COVID-19 therapies: associations with length of hospital stay, mortality and related costs

Vernaz et al., Swiss Medical Weekly, doi:10.4414/smw.2020.20446

Retrospective 840 hospitalized patients in Switzerland showing non-statistically significant lower mortality with HCQ but significantly longer hospitalization times. Confounding by indication is likely. PSM fails to adjust for severity with a 16% higher mNEWS score for HCQ vs. SOC in the matched cohort.

Time varying confounding is likely. HCQ became controversial and was suspended towards the end of the period studied, therefore HCQ use was likely more frequent toward the beginning of the study period, a time when overall treatment protocols were significantly worse.

Authors note: "overall, there was an indication bias, with the reason of prescription being associated with the outcome of interest. Indeed, patients with more severe COVID-19 were more likely to receive experimental therapies."

risk of death, 15.3% lower, RR 0.85, p = 0.71, treatment 12 of 93 (12.9%), control 16 of 105 (15.2%), NNT 43, HCQ vs. SOC, PSM.

hospitalization time, 49.0% higher, relative time 1.49, p = 0.002, treatment 93, control 105, HCQ vs. SOC, PSM.

Excluded in after exclusion results of meta analysis: substantial confounding by time likely due to declining usage over the early stages of the pandemic when overall treatment protocols improved dramatically, substantial unadjusted confounding by indication likely.

Vernaz et al., 12/31/2020, retrospective, propensity score matching, Switzerland, Europe, peer-reviewed, 15 authors.

Multifaceted highly targeted sequential multidrug treatment of early ambulatory high-risk SARS-CoV-2 infection (COVID-19)

McCullough et al., Reviews in Cardiovascular Medicine, doi:10.31083/j.rcm.2020.04.264 (Review)

Review urging early treatment of COVID-19 with sequential multidrug treatment that has been shown to be safe and effective. Proposed treatment includes zinc, vitamin D & C, quercetin, and depending on age, comorbidities, and symptoms may include >=2 of HCQ, ivermectin, favipiravir; AZM/DOXY; corticosteroids; colchicine; bamlanivimab; aspirin; LMWH; and supplemental oxygen.

McCullough et al., 12/30/2020, peer-reviewed, 58 authors.

Clinical outcomes after early ambulatory multidrug therapy for high-risk SARS-CoV-2 (COVID-19) infection

Procter et al., Reviews in Cardiovascular Medicine, doi:10.31083/j.rcm.2020.04.260

Retrospective 922 outpatients, with 320 treated early due to age>50 or comorbidities, showing 2.2% hospitalization and 0.3% death, which authors note is considerably lower than reported in other studies in their region.

At least two of zinc, HCQ, and ivermectin were used, along with one antibiotic, and budesonide and/or dexamethasone.

Procter et al., 12/30/2020, peer-reviewed, 6 authors.

Comparing ICU Admission Rates of Mild/Moderate COVID-19 Patients Treated with Hydroxychloroquine, Favipiravir, and Hydroxychloroquine plus Favipiravir

Güner et al., Journal of Infection and Public Health, doi:10.1016/j.jiph.2020.12.017

Retrospective 824 hospitalized patients in Turkey showing lower ICU admission for HCQ vs. favipiravir.

risk of ICU admission, 77.3% lower, RR 0.23, p = 0.16, treatment 604, control 100, IPTW multivariate analysis, HCQ vs. favipiravir.

Güner et al., 12/29/2020, retrospective, Turkey, Europe, peer-reviewed, 23 authors.

Incidence and severeness of COVID-19 hospitalisation in patients with inflammatory rheumatic disease: a nationwide cohort study from Denmark

Cordtz et al., Rheumatology, doi:10.1093/rheumatology/keaa897

Retrospective 58,052 rheumatic disease patients in Denmark showing that RA patients have a higher risk of COVID-19 hospitalization in general. HCQ treated patients show lower risk, although this is not statistically significant with only 3 hospitalizations for HCQ treated patients.

HR 0.76 [0.23-2.52] time-dependent exposure model
HR 0.45 [0.11-1.92] time-fixed exposure model

risk of hospitalization, 24.0% lower, HR 0.76, p = 0.67, treatment 3 of 2,722 (0.1%), control 38 of 26,718 (0.1%), NNT 3124, adjusted, time-dependent exposure model.

risk of hospitalization, 55.0% lower, HR 0.45, p = 0.28, treatment 3 of 2,722 (0.1%), control 38 of 26,718 (0.1%), adjusted, time-fixed exposure model.

Cordtz et al., 12/28/2020, retrospective, population-based cohort, Denmark, Europe, peer-reviewed, 10 authors.

Clinical features associated with COVID-19 outcome in multiple myeloma: first results from the International Myeloma Society data set

Chari et al., Blood, doi:10.1182/blood.2020008150

Retrospective multiple myeloma patients showing lower mortality with HCQ treatment, unadjusted RR 0.67, p = 0.17 (data is in the supplementary material).

risk of death, 33.1% lower, RR 0.67, p = 0.17, treatment 8 of 29 (27.6%), control 195 of 473 (41.2%), NNT 7.3.

Excluded in after exclusion results of meta analysis: unadjusted results with no group details.

Chari et al., 12/24/2020, retrospective, multiple countries, multiple regions, peer-reviewed, median age 69.0, 25 authors.

Efficacy of early hydroxychloroquine treatment in preventing COVID-19 pneumonia aggravation, the experience from Shanghai, China

Su et al., BioScience Trends, doi:10.5582/bst.2020.03340

85% lower disease progression with early use of HCQ. Retrospective 616 patients in China showing adjusted progression HR 0.15, p = 0.006.

risk of progression, 84.9% lower, HR 0.15, p = 0.006, adjusted, binary logistic regression.

improvement time, 24.0% better, relative time 0.76, p = 0.02, adjusted, Cox proportional hazards.

risk of no viral clearance, 35.8% lower, HR 0.64, p = 0.001, Cox proportional hazards.

Su et al., 12/23/2020, retrospective, China, Asia, peer-reviewed, 9 authors, study period 20 January, 2020 - 30 April, 2020, dosage 400mg days 1-10, 400mg daily for 10-14 days.

The role of organizational characteristics on the outcome of COVID-19 patients admitted to the ICU in Belgium

Taccone et al., The Lancet Regional Health - Europe, doi:10.1016/j.lanepe.2020.100019

Retrospective 1,747 ICU patients in Belgium showing lower mortality with HCQ, multivariate mixed effects analysis HCQ aOR 0.64 [0.45-0.92].

risk of death, 24.7% lower, RR 0.75, p = 0.02, treatment 449 of 1,308 (34.3%), control 183 of 439 (41.7%), NNT 14, OR converted to RR.

Taccone et al., 12/23/2020, retrospective, Belgium, Europe, peer-reviewed, 10 authors, average treatment delay 5.0 days.

Mortality in an Italian nursing home during COVID-19 pandemic: correlation with gender, age, ADL, vitamin D supplementation, and limitations of the diagnostic tests

Cangiano et al., Aging, doi:10.18632/aging.202307

73% lower mortality with HCQ. Analysis of 98 PCR+ nursing home residents in Italy, mean age 90, showing HCQ mortality RR 0.27, p = 0.03. Subject to confounding by contraindication. The paper provides the p value for regression but not the effect size.

risk of death, 73.4% lower, RR 0.27, p = 0.03, treatment 5 of 33 (15.2%), control 37 of 65 (56.9%), NNT 2.4.

Cangiano et al., 12/22/2020, retrospective, Italy, Europe, peer-reviewed, 14 authors.

Association of prescribed medications with the risk of COVID-19 infection and severity among adults in South Korea

Huh et al., International Journal of Infectious Diseases, doi:10.1016/j.ijid.2020.12.041

Retrospective database analysis with 17 cases for existing HCQ users and 5 severe cases, showing no significant difference for cases and higher risk for severe cases. However, HCQ users are likely systemic autoimmune disease patients and authors do not adjust for the very different baseline risk for these patients. Other research shows that the risk of COVID-19 for systemic autoimmune disease patients is much higher overall, Ferri et al. show OR 4.42, p<0.001 [Ferri].

1. Ferri at al., Clinical Rheumatology, doi:0.1007/s10067-020-05334-7, COVID-19 and rheumatic autoimmune systemic diseases: report of a large Italian patients series, https://link.springer.com/article/10.1007/s10067-020-05334-7.

risk of progression, 251.0% higher, RR 3.51, p = 0.11, treatment 5 of 8 (62.5%), control 873 of 2,797 (31.2%), adjusted, multivariate.

risk of case, 6.0% lower, RR 0.94, p = 0.82, treatment 17 of 122 (13.9%), control 7,324 of 43,924 (16.7%), adjusted, multivariate.

Excluded in after exclusion results of meta analysis: not fully adjusting for the different baseline risk of systemic autoimmune patients.

Huh et al., 12/19/2020, retrospective, database analysis, South Korea, Asia, peer-reviewed, 8 authors.

Clinical characteristics of COVID-19 patients hospitalized at Clinique Ngaliema, a public hospital in Kinshasa, in the Democratic Republic of Congo: A retrospective cohort study

Matangila et al., PLoS ONE, doi:10.1371/journal.pone.0244272

55% lower death with HCQ+AZ. Retrospective 160 hospitalized patients in the Democratic Republic of Congo, 92% receiving HCQ+AZ, showing adjusted OR 0.24 [0.03-2.2].

risk of death, 54.9% lower, RR 0.45, p = 0.21, treatment 25 of 147 (17.0%), control 8 of 13 (61.5%), NNT 2.2, adjusted, OR converted to RR.

Matangila et al., 12/18/2020, retrospective, DR Congo, Africa, peer-reviewed, median age 54.0, 12 authors, average treatment delay 7.0 days.

Prevalence and 30-day mortality in hospitalized patients with COVID-19 and prior lung diseases

Signes-Costa et al., Archivos de Bronconeumología, doi:10.1016/j.arbres.2020.11.012

47% lower mortality with HCQ/CQ. Retrospective 1,271 patients with lung disease in Canada, China, Cuba, Ecuador, Germany, Italy and Spain, 83% treated with HCQ/CQ.

Multivariable Cox regression HCQ/CQ mortality hazard ratio HR 0.53, p < 0.001.

risk of death, 47.0% lower, RR 0.53, p < 0.001, treatment 4,854, control 993, adjusted.

Signes-Costa et al., 12/16/2020, retrospective, multiple countries, multiple regions, peer-reviewed, 28 authors.

Prophylactic use of Hydroxychloroquine among Physicians working in Pandemic Hospitals

Gönenli et al., Research Square, doi:0.21203/rs.3.rs-107937/v1 (Preprint)

Small prophylaxis survey showing lower, but not statistically significant, progression to pneumonia (3 of 148 HCQ, 12 of 416 control), RR 0.70, p = 0.77. There was a higher incidence of cases with HCQ, OR 1.19, p = 0.58, which may be due to survey bias, treatment self-selection, and inconsistent regimens. Improvement on severity may be related to the much higher HCQ concentration in lung tissue, and also reflect that binary PCR does not distinguish replication-competence. Details of the pneumonia numbers for treatment/control are from the author.

risk of pneumonia, 29.7% lower, RR 0.70, p = 0.77, treatment 3 of 148 (2.0%), control 12 of 416 (2.9%), NNT 117.

risk of case, 18.9% higher, RR 1.19, p = 0.58, treatment 8 of 148 (5.4%), control 20 of 416 (4.8%), OR converted to RR.

Gönenli et al., 12/16/2020, retrospective, Turkey, Europe, preprint, survey, 4 authors.

Clinical and Demographic Characteristics of COVID-19 Patients Admitted in a Tertiary Care Hospital in the Dominican Republic

De Luna et al., medRxiv, doi:10.1101/2020.12.11.20247437 (Preprint)

Retrospective 150 patients in the Dominican Republic, 132 treated with HCQ, showing higher mortality with treatment in unadjusted results. Confounding by indication is likely.

risk of death, 104.5% higher, RR 2.05, p = 0.69, treatment 15 of 132 (11.4%), control 1 of 18 (5.6%).

Excluded in after exclusion results of meta analysis: unadjusted results with no group details, substantial unadjusted confounding by indication likely.

De Luna et al., 12/14/2020, retrospective, Dominican Republic, Caribbean, preprint, 10 authors.

SARS-CoV‑2, a virus with many faces: a series of cases with prolonged persistence of COVID-19 symptoms

Sofian et al., Wiener Medizinische Wochenschrift, doi:10.1007/s10354-020-00793-8

Report on a series of 10 patients experiencing prolonged COVID-19 symptoms that were given HCQ 250mg bid for 5 days, with resolution of symptoms in all cases, and patients reporting they felt much better 2 days after treatment initiation.

Sofian et al., 12/14/2020, peer-reviewed, 7 authors.

Clinical characteristics and short-term prognosis of in-patients with diabetes and COVID-19: A retrospective study from an academic center in Belgium

Orioli et al., Diabetes & Metabolic Syndrome: Clinical Research & Reviews, doi:10.1016/j.dsx.2020.12.020

Small retrospective study of 73 diabetic patients in Belgium, 55 HCQ patients, showing HCQ RR 0.87, p = 1.0.

risk of death, 12.7% lower, RR 0.87, p = 1.00, treatment 8 of 55 (14.5%), control 3 of 18 (16.7%), NNT 47.

Orioli et al., 12/14/2020, retrospective, Belgium, Europe, peer-reviewed, 9 authors.

Predicting mortality in SARS-COV-2 (COVID-19) positive patients in the inpatient setting using a Novel Deep Neural Network

Naseem et al., medRxiv, doi:10.1101/2020.12.13.20247254 (Preprint)

Retrospective 1,214 hospitalized patients in Pakistan, 77 HCQ patients, showing 33% lower mortality with HCQ, multivariate Cox HR 0.67, p = 0.34.

risk of death, 33.3% lower, RR 0.67, p = 0.34, treatment 77, control 1,137, multivariate Cox.

Naseem et al., 12/14/2020, retrospective, Pakistan, South Asia, preprint, 5 authors.

Antiandrogens	(meta)	Lactoferrin	(meta)
Aspirin	(meta)	Melatonin	(meta)
Bamlaniv../e..	(meta)	Metformin	(meta)
Bebtelovimab	(meta)	Molnupiravir	(meta)
Bromhexine	(meta)	N-acetylcys..	(meta)
Budesonide	(meta)	Nigella Sativa	(meta)
Cannabidiol	(meta)	Nitazoxanide	(meta)
Casirivimab/i..	(meta)	Paxlovid	(meta)
Colchicine	(meta)	Peg.. Lambda	(meta)
Conv. Plasma	(meta)	Povidone-Iod..	(meta)
Curcumin	(meta)	Probiotics	(meta)
Diet	(meta)	Proxalutamide	(meta)
Ensitrelvir	(meta)	Quercetin	(meta)
Ensovibep	(meta)	Remdesivir	(meta)
Exercise	(meta)	Sleep	(meta)
Famotidine	(meta)	Sotrovimab	(meta)
Favipiravir	(meta)	Tixagev../c..	(meta)
Fluvoxamine	(meta)	Vitamin A	(meta)
Hydroxychlor..	(meta)	Vitamin C	(meta)
Iota-carragee..	(meta)	Vitamin D	(meta)
Ivermectin	(meta)	Zinc	(meta)

Other Treatments		Global Adoption