The U.S. has revoked the emergency authorization for malaria drugs championed by President Donald Trump for treating COVID-19 amid growing evidence they don't work and could cause serious side effects.

The Food and Drug Administration (FDA) said on Monday the drugs hydroxychloroquine and chloroquine were unlikely to be effective in treating the coronavirus. Citing reports of heart complications, the agency said the drugs' unproven benefits "do not outweigh the known and potential risks."