Mega-trial of ‘hot’ Covid-19 candidate drug hydroxychloroquine resumes

In spite of findings published two months ago in the Journal of the American Medical Association (JAMA), that hydroxychloroquine, when used to treat COVID-19, caused cardiac arrhythmias, a major global trial of the drug is about to resume. British regulators have approved the resumption of the so-called COPCOV trial involving 40 000 healthcare and other at-risk workers. The stop-start trial, the biggest and therefore the most important, was halted when inconclusive or red-flag results from smaller-scale trials left regulators in the UK and the USA nervous. The Federal Drug Administration (FDA) revoked emergency use of the anti-malarial drug after reviewing trials showing either no benefit or unproven C-19 efficacy and safety, the arrhythmia being the most concerning. However, the current randomised controlled trial is expected to give a definitive answer. President Donald Trump controversially claimed to have taken the drug for a fortnight after some of his colleagues fell victim to the coronavirus, citing smaller, more hopeful but inconclusive studies in France and Italy. However, his motivation is under question. If hydroxychloroquine becomes an accepted treatment, several pharmaceutical companies stand to profit, including shareholders and senior executives with connections to the president, who reportedly has a small personal financial interest in Sanofi, the French drug company that makes Plaquenil, the brand-name version of hydroxychloroquine. Hydroxychloroquine trials in South Africa, where ethics and regulatory approvals were obtained a month ago, continued unaffected. – Chris Bateman 

By Kate Kelland

LONDON (Reuters) – A global trial designed to test whether the anti-malaria drugs hydroxychloroquine and chloroquine can prevent infection with COVID-19 is to restart after being approved by British regulators.

The Medicines and Healthcare Products Regulatory Agency (MHRA) took its decision on what is known as the COPCOV trial after hydroxychloroquine was found in another British trial to have no benefit as a treatment for patients already infected with COVID-19, the disease caused by the new coronavirus.

The COPCOV study was paused pending review after the treatment trial results.

It is a randomised, placebo-controlled trial that is aiming to enrol 40,000 healthcare workers and other at-risk staff around the world, and is being led by the Oxford University's Mahidol Oxford Tropical Medicine Research Unit (MORU) in the Thai capital, Bangkok.

U.S. President Donald Trump said in March hydroxychloroquine could be a game-changer and then said he was taking it himself, even after the U.S. regulator, the Food and Drug Administration (FDA), advised that its efficacy and safety were unproven.

The FDA later revoked emergency use authorisation for the drugs to treat COVID-19, after trials showed they were of no benefit as treatments.

But White, who is co-leading the COPCOV trial, said studies of the drugs as a potential preventative medicine had not yet given a conclusive answer.

"Hydroxychloroquine could still prevent infections, and this needs to be determined in a randomised controlled trial," he said in a statement. "The question whether (it) can prevent COVID-19 or not remains as pertinent as ever."

White's team said recruitment of British health workers would resume this week, and said plans were under way for new sites in Thailand and Southeast Asia, Africa and South America. Results are expected by the end of this year.

(Reporting by Kate Kelland, editing by Paul Sandle and Timothy Heritage)