The drug hydroxychloroquine, once touted by Donald Trump as a pandemic "game-changer", should not be used to prevent Covid-19 and has no meaningful effect on patients already infected, a World Health Organization expert panel said on Tuesday.
The anti-inflammatory drug should not be used in the fight against the pandemic, the WHO's Guideline Development Group (GDG) expert panel wrote in the BMJ British medical journal, and is "not worthwhile" exploring in further research studies of possible Covid-19 treatments.
This "strong recommendation", the experts said, is based on high-certainty evidence from six randomised controlled trials involving more than 6,000 participants both with and without known exposure to Covid-19.
Former US President Trump said last March that hydroxychloroquine could be a game-changer in the coronavirus pandemic. He also said he was taking it himself, even after the US medicines regulator, the Food and Drug Administration (FDA), advised that its efficacy and safety were unproven.
But the WHO's experts said they now "judged that almost all people would not consider this drug worthwhile".
"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," they wrote.
The WHO noted in a statement that the recommendation is a so-called "living guideline" on potential drugs for Covid-19.
The guidelines, which can be updated as new evidence emerges, are designed to advise doctors and healthcare providers on managing the respiratory disease and help them make better decisions for patients.