FDA revokes emergency use authorisation for hydroxychloroquine


On June 15, FDA revoked the emergency use authorisation for hydroxychloroquine and chloroquine that was issued on March 27. The FDA said it is no longer reasonable to believe that the drugs may be effective in treating COVID-19 nor the potential benefits outweigh potential risks.

On June 15, the U.S. Food and Drug Administration revoked the emergency use authorisation (EUA) issued for two drugs — hydroxychloroquine sulfate and chloroquine phosphate — for use in certain hospitalised COVID-19 patients. The FDA had issued the authorisation on March 27.

The FDA said that it has “determined that the statutory criteria for EUA are no longer met.  Specifically, FDA has determined that [both drugs] are unlikely to be effective in treating COVID-19 for the authorised uses in the EUA”.

The FDA further added: “In light of ongoing serious cardiac adverse events and other serious side effects, the known and potential benefits of chloroquine and hydroxychloroquine no longer outweigh the known and potential risks for the authorised use.” One April 24, the FDA had cautioned that hydroxychloroquine should not be used outside of the hospital setting or a clinical trial due to risk of heart rhythm problems.

The Saga ends

This brings to an end the saga of using hydroxychloroquine for treating COVID-19 patients after President Donal Trump backed the drug. He had famously said: “It’s a very strong, powerful medicine. But it doesn’t kill people. We have some very good results and some very good tests,” Trump told reporters on April 6, adding: “What really do we have to lose?”

In a letter to Gary L. Disbrow, Deputy Assistant Secretary Director, Medical Countermeasure Programs Biomedical Advanced Research and Development Authority (BARDA), FDA Chief Scientist RADM Denise M. Hinton said “based on a review of new information and a re-evaluation of information available at the time the EUA was issued, FDA now concludes that these criteria are no longer met”.

“FDA has concluded that, based on this new information and other information, it is no longer reasonable to believe that oral formulations of hydroxychloroquine and chloroquine may be effective in treating COVID-19, nor is it reasonable to believe that the known and potential benefits of these products outweigh their known and potential risks,” the Chief Scientist said in the letter.

Four reasons why EUA was revoked

According to the letter, Dr. Hinton had based his decision to revoke the authorisation for the following four reasons: 1) The suggested dosing regimens for both the drugs are unlikely to produce an antiviral effect, 2) Earlier observations of decreased viral shedding with either of the two treatments have not been consistently replicated and recent data from a randomised controlled trial assessing probability of negative conversion showed no difference between hydroxychloroquine and standard of care alone, 3) Current U.S. treatment guidelines do not recommend the use of these drugs in hospitalized patients with COVID-19 outside of a clinical trial, and 4) Recent data from a large randomised controlled trial (the RECOVERY Trial) showed no evidence of benefit for mortality or other outcomes such as hospital length of stay or need for mechanical ventilation of HCQ treatment in hospitalised patients with COVID-19.

Published in The Hindu on June 16, 2020