Mortality outcomes with hydroxychloroquine and chloroquine in COVID-19 from an international collaborative meta-analysis of randomized trials

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Abstract

Substantial COVID-19 research investment has been allocated to randomized clinical trials (RCTs) on hydroxychloroquine/chloroquine, which currently face recruitment challenges or early discontinuation. We aim to estimate the effects of hydroxychloroquine and chloroquine on survival in COVID-19 from all currently available RCT evidence, published and unpublished. We present a rapid meta-analysis of ongoing, completed, or discontinued RCTs on hydroxychloroquine or chloroquine treatment for any COVID-19 patients (protocol: https://osf.io/QESV4/ ). We systematically identified unpublished RCTs (ClinicalTrials.gov, WHO International Clinical Trials Registry Platform, Cochrane COVID-registry up to June 11, 2020), and published RCTs (PubMed, medRxiv and bioRxiv up to October 16, 2020). All-cause mortality has been extracted (publications/preprints) or requested from investigators and combined in random-effects meta-analyses, calculating odds ratios (ORs) with 95% confidence intervals (CIs), separately for hydroxychloroquine and chloroquine. Prespecified subgroup analyses include patient setting, diagnostic confirmation, control type, and publication status. Sixty-three trials were potentially eligible. We included 14 unpublished trials (1308 patients) and 14 publications/preprints (9011 patients). Results for hydroxychloroquine are dominated by RECOVERY and WHO SOLIDARITY, two highly pragmatic trials, which employed relatively high doses and included 4716 and 1853 patients, respectively (67% of the total sample size). The combined OR on all-cause mortality for hydroxychloroquine is 1.11 (95% CI: 1.02, 1.20; I² = 0%; 26 trials; 10,012 patients) and for chloroquine 1.77 (95%CI: 0.15, 21.13, I² = 0%; 4 trials; 307 patients). We identified no subgroup effects. We found that treatment with hydroxychloroquine is associated with increased mortality in COVID-19 patients, and there is no benefit of chloroquine. Findings have unclear generalizability to outpatients, children, pregnant women, and people with comorbidities.

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  1. SciScore for 10.1101/2020.09.16.20194571: (What is this?)

    Please note, not all rigor criteria are appropriate for all manuscripts.

    Table 1: Rigor

    Institutional Review Board Statementnot detected.
    Randomization16 We considered all clinical trials that reported randomly allocating patients with confirmed or suspected SARS-CoV-2 infection to a treatment protocol containing HCQ or CQ (for any duration or dose) or the same treatment protocol not containing HCQ or CQ.
    Blindingnot detected.
    Power Analysisnot detected.
    Sex as a biological variablenot detected.

    Table 2: Resources

    Software and Algorithms
    SentencesResources
    17 We additionally searched PubMed and the Cochrane COVID-19 trial registry (covering preprints, trial registries and literature databases) by June 11, 2020, using terms related to HCQ and CQ combined with terms for COVID-19 and a standard RCT filter (Supplement 1).
    PubMed
    suggested: (PubMed, RRID:SCR_004846)

    Results from OddPub: We did not detect open data. We also did not detect open code. Researchers are encouraged to share open data when possible (see Nature blog).


    Results from LimitationRecognizer: We detected the following sentences addressing limitations in the study:
    Our analysis has some limitations. First, although we adopted a comprehensive, systematic search strategy, our real-time initiative differs from traditional systematic reviews. We focused on collecting unpublished information, aiming to rapidly secure as much trial evidence as possible. We did not review individual trials, nor did we stratify results according to patient characteristics. Such analyses are planned in future publications using in-depth details disclosed in individual trial publications to come.44–46 The exploratory subgroup analyses did not support the hypothesis that blinding/use of placebo is associated with the observed effect (the test for an interaction gives p=0.15 and the OR is 0.88 with wide CIs [0.55 to 1.41], compatible with the overall effect); moreover, attrition was negligible (median 0%, IQR 0% to 0%; range 0 to 19.5%). A meta-epidemiological study shows little evidence that mortality results would be affected by lack of blinding, or problems in randomization and allocation concealment, in contrast to less objective outcomes.47 Second, a majority of the potentially eligible trials were not available. Despite going far beyond the standard review of published evidence, we expect additional results from future trials on CQ to narrow the uncertainty of the treatment effect and possibly reveal benefits or harms not discernible based on the current evidence. We plan to perform an update when substantial additional evidence becomes available. Finally, al...

    Results from TrialIdentifier: No clinical trial numbers were referenced.


    Results from Barzooka: We did not find any issues relating to the usage of bar graphs.


    Results from JetFighter: We did not find any issues relating to colormaps.


    Results from rtransparent:
    • Thank you for including a conflict of interest statement. Authors are encouraged to include this statement when submitting to a journal.
    • Thank you for including a funding statement. Authors are encouraged to include this statement when submitting to a journal.
    • No protocol registration statement was detected.

    About SciScore

    SciScore is an automated tool that is designed to assist expert reviewers by finding and presenting formulaic information scattered throughout a paper in a standard, easy to digest format. SciScore checks for the presence and correctness of RRIDs (research resource identifiers), and for rigor criteria such as sex and investigator blinding. For details on the theoretical underpinning of rigor criteria and the tools shown here, including references cited, please follow this link.

  2. SciScore for 10.1101/2020.09.16.20194571: (What is this?)

    Please note, not all rigor criteria are appropriate for all manuscripts.

    Table 1: Rigor

    Institutional Review Board Statementnot detected.RandomizationWe considered all clinical trials that reported randomly allocating patients with confirmed or suspected SARS-CoV-2 infection to a treatment protocol containing HCQ or CQ (for any duration or dose) or the same treatment protocol not containing HCQ or CQ.BlindingIn most trials, patients and clinicians were aware of the treatment (13 trials; 50%), while in one trial (4%) the patients were blinded and in eleven trials (42%) patients and clinicians were blinded (Table 2).Power Analysisnot detected.Sex as a biological variablenot detected.

    Table 2: Resources

    Software and Algorithms
    SentencesResources
    16 We additionally searched PubMed and the Cochrane COVID-19 trial registry (covering preprints, trial registries and literature databases) by June 11, 2020, using terms related to HCQ and CQ combined with terms for COVID-19 and a standard RCT filter (Supplement 1).
    PubMed
    suggested: (PubMed, RRID:SCR_004846)

    Results from OddPub: We did not detect open data. We also did not detect open code. Researchers are encouraged to share open data when possible (see Nature blog).


    Results from LimitationRecognizer: We detected the following sentences addressing limitations in the study:

    Our analysis has some limitations. First, although we adopted a comprehensive, systematic search strategy, our real-time initiative differs from traditional systematic reviews. We focused on collecting unpublished information, aiming to rapidly secure as much trial evidence as possible. We did not review individual trials, nor break down results according to patient characteristics. Such analyses are planned in future publications using in-depth details disclosed in individual trial publications to come.38–40 However, consistent findings in placebo-controlled, double-blinded and open-label trials indicate an overall low risk of bias across trials; moreover, attrition was negligible (median 0%, IQR 0% to 0%; range 0 to19.5%). Meta-epidemiological work shows that mortality results are least affected by lack of blinding, or problems in randomization and allocation concealment as compared with other outcomes. 41 Second, a majority of the potentially eligible trials were not available. Despite going far beyond the standard review of published evidence, we expect additional results from future trials to narrow the uncertainty of the treatment effect and possibly reveal benefits or harms not discernible based on the current evidence. Of the unavailable trials, the WHO Solidarity trial may have the largest sample size and provide most mortality data. We plan to perform an update when substantial additional evidence becomes available. Finally, although conclusions were robust across s...


    Results from TrialIdentifier: We found the following clinical trial numbers in your paper:

    IdentifierStatusTitle
    NCT04261517CompletedEfficacy and Safety of Hydroxychloroquine for Treatment of C...
    NCT04381936RecruitingRandomised Evaluation of COVID-19 Therapy
    NCT04316377Active, not recruitingNorwegian Coronavirus Disease 2019 Study
    NCT04384380CompletedEfficacy and Tolerability of Hydroxychloroquine in Adult Pat...
    NCT04308668CompletedPost-exposure Prophylaxis / Preemptive Therapy for SARS-Coro...
    NCT04304053CompletedTreatment of COVID-19 Cases and Chemoprophylaxis of Contacts...
    NCT04322123Active, not recruitingSafety and Efficacy of Hydroxychloroquine Associated With Az...
    NCT04329923RecruitingThe PATCH Trial (Prevention And Treatment of COVID-19 With H...
    NCT04345289RecruitingEfficacy and Safety of Novel Treatment Options for Adults Wi...
    NCT04335552TerminatedPragmatic Factorial Trial of Hydroxychloroquine, Azithromyci...
    NCT04342650CompletedChloroquine Diphosphate in the Prevention of SARS in Covid-1...
    NCT04323527CompletedChloroquine Diphosphate for the Treatment of Severe Acute Re...
    NCT04315896Active, not recruitingHydroxychloroquine Treatment for Severe COVID-19 Pulmonary I...
    NCT04333654TerminatedHydroxychloroquine in Outpatient Adults With COVID-19
    NCT04353336RecruitingEfficacay of Chloroquine or Hydroxychloroquine in COVID-19 T...
    NCT04338698RecruitingHydroxychloroquine, Oseltamivir and Azithromycin for the Tre...
    NCT04369742SuspendedTreating COVID-19 With Hydroxychloroquine (TEACH)
    NCT04345692RecruitingA Randomized Controlled Clinical Trial: Hydroxychloroquine f...
    NCT02735707RecruitingRandomized, Embedded, Multifactorial Adaptive Platform Trial...
    NCT04325893RecruitingHydroxychloroquine Versus Placebo in COVID-19 Patients at Ri...
    NCT04342221RecruitingHydroxychloroquine for COVID-19
    NCT04340544RecruitingHydroxychloroquine for the Treatment of Mild COVID-19 Diseas...


    Results from Barzooka: We did not find any issues relating to the usage of bar graphs.


    Results from JetFighter: We did not find any issues relating to colormaps.


    About SciScore

    SciScore is an automated tool that is designed to assist expert reviewers by finding and presenting formulaic information scattered throughout a paper in a standard, easy to digest format. SciScore checks for the presence and correctness of RRIDs (research resource identifiers), and for rigor criteria such as sex and investigator blinding. For details on the theoretical underpinning of rigor criteria and the tools shown here, including references cited, please follow this link.