Researchers decided to halt the hydroxychloroquine portion of a World Health Organization trial of potential COVID-19 treatments, an official said.

A group of experts advising the WHO’s Solidarity trial concluded that the drug shows no benefit compared to the standard of care in reducing deaths, Ana Maria Henao-Restrepo, a WHO medical officer, said at a briefing in Geneva.

The U.S. Food and Drug Administration on Monday revoked emergency-use authorization for hydroxychloroquine and chloroquine, a related antimalarial drug, after determining they were unlikely to treat the virus and could have dangerous side effects. U.S. President Donald Trump has touted hydroxychloroquine as a treatment for the coronavirus since the early weeks of the global outbreak, calling it a “game-changer.”

The decision for the WHO’s trial was made by independent experts and doesn’t constitute a guideline by the agency, Henao-Restrepo said. The decision also didn’t consider whether hydroxychloroquine could help prevent COVID-19, she said.