The anti-inflammatory drug hydroxychloroquine should not be used to prevent infection in people who do not have Covid-19, says a WHO guideline development group panel of experts.
In a report in The BMJ, the experts' strong recommendation is based on high-certainty evidence from six randomised controlled trials involving more than 6,000 participants with and without known exposure to coronavirus.
The evidence showed hydroxychloroquine had no meaningful effect on death and admission to hospital.
But moderate-certainty evidence showed it had no meaningful effect on laboratory-confirmed Covid-19 infection, and probably increased the risk of adverse effects.
As such, the panel states that the drug is no longer a research priority and that resources should go towards more promising drugs to prevent Covid-19.
This guideline applies to all people who do not have Covid-19, regardless of their exposure to an infected person.
The panel judged that almost all people would not consider this drug worthwhile.
It also decided that factors such as resources, feasibility, acceptability and equity for countries and healthcare systems were unlikely to alter the recommendation.
The recommendation is the first version of a living guideline for drugs to prevent Covid-19, developed by the World Health Organisation with the support of the Magic Evidence Ecosystem Foundation.
Its aim is to provide trustworthy guidance on the management of Covid-19 and help doctors to make better decisions.
Living guidelines are useful in fast-moving research areas such as Covid-19 because they allow researchers to update vetted and peer-reviewed evidence, the WHO says.
It plans to add recommendations for other Covid-19 preventive drugs to the guideline as evidence becomes available.
