The French government on Wednesday banned treatment of COVID-19 patients with hydroxychloroquine, a controversial and potentially harmful drug that US President Donald Trump has said he is taking preventively.
The move came after two French advisory bodies and the World Health Organization warned this week that the drug -- a treatment for rheumatoid arthritis and lupus -- had been shown to be potentially dangerous in several studies.
The urgency of the coronavirus outbreak has prompted some doctors to prescribe the drug despite a lack of research to demonstrate its efficacy against the novel coronavirus.
Among them were a French infectious disease specialist who caught the ear of Trump, who stunned his own administration last week by revealing he was taking hydroxychloroquine as a preventive measure against COVID-19.
Under the new French rules, the drug can be used only in clinical trials to test its efficacy against coronavirus -- making it unclear if the French doctor, Didier Raoult, would be able to continue using it at his hospital in Marseille in the south.
Raoult has already rejected a comprehensive study published last week in The Lancet medical journal, which found that administering hydroxychloroquine or its related compound chloroquine actually increased the risk of dying for many patients.
Hydroxychloroquine, also used to treat malaria, is sold under the brand name Plaquenil by French pharma giant Sanofi, which promised to offer governments millions of doses if studies proved it could be safely used in the coronavirus fight.