MONDAY, June 15, 2020 (HealthDay News) -- The U.S. Food and Drug Administration has withdrawn its emergency authorization for the use of two malaria drugs championed by President Donald Trump in the fight against COVID-19.
The agency said in a letter Monday that the drugs, hydroxychloroquine and chloroquine, are "unlikely to be effective" as treatments for the coronavirus, The New York Times reported.
The FDA now says the drugs should not be used outside of clinical trials.
Despite its earlier cautious approval, this isn't the first time the agency has voiced concern about the experimental medicines. The FDA had already issued a warning that they might cause dangerous heart rhythm abnormalities.
However, despite a lack of evidence supporting the drugs as coronavirus preventatives, Trump not only touted the drugs, he announced that he took hydroxychloroquine for about two weeks after two White House staffers tested positive for COVID-19.
The FDA in March sanctioned use of the drugs in hospitals to treat COVID-19 patients. But after reviewing data on the drugs, the FDA has now concluded that the risks of taking them outweigh any benefit. This was especially true for hydroxychloroquine, the Times said.
FDA chief scientist Denise Hinton said in the letter that the Biomedical Advanced Research and Development Authority had asked that the drugs' authorization for COVID treatment be revoked. The authority is a division of the U.S. Department of Health and Human Services that oversees treatments in public health emergencies.
Hydroxychloroquine and chloroquine, which have long been used legitimately to treat malaria and lupus, have had their share of bad press when it came to their use against COVID-19.
Two major studies cast doubts on the drugs but were retracted on June 4 because the data used could not be verified. One report was published May 22 in The Lancet, while the other was published May 1 in the New England Journal of Medicine.
Both concluded that hydroxychloroquine and chloroquine were of no use in treating COVID-19 and might even cause heart harms.
Another study -- this time a "gold standard" randomized clinical trial -- found that hydroxychloroquine could not prevent COVID-19 any better than a placebo.
Also, 40% of those taking hydroxychloroquine developed side effects including nausea, upset stomach or diarrhea. However, no serious side effects or heart problems occurred in that study, the researchers said.
In that trial, published online June 3 in the New England Journal of Medicine, researchers randomly assigned more than 800 people in the United States and Canada to take hydroxychloroquine, or a placebo, for five days. All of the participants had been exposed to people with COVID-19.
Overall, 12% of those taking hydroxychloroquine developed COVID-19 as did 14% taking the placebo, the findings showed. The difference was not statistically significant, the study authors noted.
"Our objective was to answer the question of whether hydroxychloroquine worked to prevent disease or did not work," said lead researcher Dr. David Boulware, an infectious disease doctor at the University of Minnesota. "While we are disappointed that this did not prevent COVID-19, we are pleased that we were able to provide a conclusive answer," Boulware said in a university news release.
The U.S. Centers for Disease Control and Prevention has more about COVID-19.