New Delhi: The US Food and Drug Administration revoked the emergency use authorisation of anti-malarial drugs chloroquine (CQ) and hydroxychloroquine (HCQ) in the treatment of  coronavirus patients, saying that it was no longer reasonable to believe that oral formulations of these medicines may be effective in treating the respiratory illness caused by COVID-19. The FDA asserted that it took the decision on the basis of new information, including clinical trial data results. Also Read - Closing of Schools is Impacting Your Child's Mental Health, Here is What You Need to do

In a letter addressed to Gary Disbrow of Biomedical Advanced Research and Development Authority (BARDA), FDA chief scientist Denise Hinton, said as of the date of this letter (June 15), the oral formulations of hydroxychloroquine (HCQ) and (chloroquine) CQ are no longer authorised by the FDA to treat COVID-19. Also Read - Coronavirus: These States Have Recovery Rate Higher Than National Average | Check List Here

FDA now believes that the suggested dosing regimens for CQ and HCQ are unlikely to produce an antiviral effect, said  Hinton. Also Read - Tamil Nadu Lockdown Extension News: State Extends Suspension of Bus Services Till July 31

“Earlier observations of decreased viral shedding with HCQ or CQ treatment have not been consistently replicated and recent data from a randomised controlled trial assessing probability of negative conversion showed no difference between HCQ and standard of care alone,” he added.

Current US treatment guidelines do not recommend the use of CQ or HCQ in hospitalised patients with COVID-19 outside of a clinical trial, and the NIH guidelines now recommend against such use outside of a clinical trial, the FDA said.

“Recent data from a large randomised controlled 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,” the letter said.

Earlier, US President Donald Trump had called hydroxychloroquine a ‘game-changer’ drug in the fight against COVID-19. In April, at Trump’s request, India had allowed the export of 50 million HCQ tablets to treat COVID-19 patients in America.

Last month, the US president had also revealed that he was taking hydroxychloroquine daily to ward off the deadly coronavirus.