COVID-19 Evidence Alerts
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Current best evidence for clinical care (more info)

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Primary Prevention Lamontagne F, Agoritsas T, Siemieniuk R, et al. A living WHO guideline on drugs to prevent covid-19. BMJ. 2021 Mar 1;372:n526. doi: 10.1136/bmj.n526.

CLINICAL QUESTION: What is the role of drugs in preventing covid-19? WHY DOES THIS MATTER?: There is widespread interest in whether drug interventions can be used for the prevention of covid-19, but there is uncertainty about which drugs, if any, are effective. The first version of this living guideline focuses on the evidence for hydroxychloroquine. Subsequent updates will cover other drugs being investigated for their role in the prevention of covid-19.

RECOMMENDATION: The guideline development panel made a strong recommendation against the use of hydroxychloroquine for individuals who do not have covid-19 (high certainty).

HOW THIS GUIDELINE WAS CREATED: This living guideline is from the World Health Organization (WHO) and provides up to date covid-19 guidance to inform policy and practice worldwide. Magic Evidence Ecosystem Foundation (MAGIC) provided methodological support. A living systematic review with network analysis informed the recommendations. An international guideline development panel of content experts, clinicians, patients, an ethicist and methodologists produced recommendations following standards for trustworthy guideline development using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

UNDERSTANDING THE NEW RECOMMENDATION: The linked systematic review and network meta-analysis (6 trials and 6059 participants) found that hydroxychloroquine had a small or no effect on mortality and admission to hospital (high certainty evidence). There was a small or no effect on laboratory confirmed SARS-CoV-2 infection (moderate certainty evidence) but probably increased adverse events leading to discontinuation (moderate certainty evidence). The panel judged that almost all people would not consider this drug worthwhile. In addition, the panel decided that contextual factors such as resources, feasibility, acceptability, and equity for countries and healthcare systems were unlikely to alter the recommendation. The panel considers that this drug is no longer a research priority and that resources should rather be oriented to evaluate other more promising drugs to prevent covid-19.

UPDATES: This is a living guideline. New recommendations will be published in this article and signposted by update notices to this guideline.

READERS NOTE: This is the first version of the living guideline for drugs to prevent covid-19. It complements the WHO living guideline on drugs to treat covid-19. When citing this article, please consider adding the update number and date of access for clarity.

Discipline / Specialty Area Score
Family Medicine (FM)/General Practice (GP)
Emergency Medicine
General Internal Medicine-Primary Care(US)
Infectious Disease
Hospital Doctor/Hospitalists
Internal Medicine
Public Health
Comments from MORE raters

Emergency Medicine rater

I think most physicians are already aware of the lack of evidence for hydroxychloroquine but this is a great template for evidence based guidance from the WHO on other drugs with the potential to prevent or treat COVID-19.

General Internal Medicine-Primary Care(US) rater

This meta analysis extends the findings from trials of hydroxychloroquine (HCQ) therapy for patients who contract COVID-19, in that it has no effect in prevention of COVID-19 infection, just as it did not improve outcomes for patients with COVID-19, and may result in harm. It's main utility is in providing evidence for clinicians whose patients ask about its efficacy.

General Internal Medicine-Primary Care(US) rater

This is a living guideline, so it is a very practical approach, for any new disease. Recommendations will be updated frequently. It’s a practical approach to rapidly inform policy and practice worldwide during the covid-19 pandemic. With this type of work, they don´t recommend the use of hydroxychloroquine as prophylaxis in individuals who do not have covid-19, as it increases the risk of adverse effects. They found evidence regarding the lack of effect of hydroxychloroquine prophylaxis. This suggests that funders and researchers should reconsider the initiation or continuation of these expensive and inefficient trials.

Hospital Doctor/Hospitalists rater

As an Internist treating patients with COVID-19, I found this information useful.

Infectious Disease rater

W.H.O. recommendation against hydroxychloroquine for prevention of COVID-19 as published in BMJ. I found the Visual Summary confusing.

Public Health rater

In my view, this is a guideline on an issue that almost everybody knows.