Trump’s Covid-19 Drug to Get More Scrutiny in 40,000-Person Test

(Bloomberg) -- The antimalarial drug that U.S. President Donald Trump touted for Covid-19 is getting another chance, as a global clinical trial will try to determine the treatment's effectiveness in preventing coronavirus infection.

A trial led by Bangkok-based Mahidol Oxford Tropical Medicine Research Unit is now recruiting health workers in contact with Covid-19 patients to study whether hydroxychloroquine, as well as its sister drug chloroquine, can prevent the infection.

The effectiveness of the two treatments has been hotly debated after Trump touted them as potential game changers against the virus. One study that showed the drugs were linked to an increased risk of death and heart ailments was retracted last month.

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“This drug has been more intensely politicized than anything else I've ever heard of,” Nicholas White, professor of tropical medicine and co-principal investigator of the study, said in an interview. “It became very polarizing and had a very, very damaging effect on the one thing we all want to find out, which is the truth.”

Hundreds of treatments are being tested worldwide as researchers try to find a way to slow the pandemic's spread. But the science around almost all of them is still uncertain and the history of other epidemics shows that few slam-dunk treatments are ever found.

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Although a U.K. trial recently reported that hydroxychloroquine wasn't effective when used on hospitalized patients, the focus of that study and many others was on using the drug to treat Covid-19, not to prevent infections. White said he expects the drug to work best before exposure to the virus or just after.

One trial that did focus on prevention showed that the malaria drug failed to offer patients any protection. That study, published in the New England Journal of Medicine last month, involved 821 people given hydroxychloroquine for five days.

The Mahidol Oxford-led study will involve a longer time frame and more people, testing 40,000 participants over several months. It plans to recruit people in Thailand, the U.K. and several study sites in Africa and South America.

Randomized Trial

It will be a double-blind, randomized, placebo-controlled trial, and is sponsored by a grant from the Covid-19 Therapeutics Accelerator, an initiative of the Bill & Melinda Gates Foundation, Wellcome and Mastercard.

It's important to know whether these drugs can prevent Covid-19, as about 20% of the world's population are living in countries where they are recommended as protection against the virus, according to White. But with lots of bad publicity around the drug, he said the trial and the recruitment isn't going to be easy.

“The general public and most health-care workers are not at all as positive about these drugs as they were three or four months ago,” he said. “It would have been much easier -- and we would have the answer now I'm sure -- if these drugs had not been politicized.”

White said the trial and recruitment of participants was paused after the now-retracted paper in The Lancet suggested hydroxychloroquine carried the risk of heart side effects and death. That study was pulled after questions arose about the accuracy of the underlying data.

The Mahidol Oxford-led trial got a green light to go ahead again from the U.K. medicines agency after a five-week hiatus.

“The evidence is that the dosage that's being used in this trial is safe. In fact, there is no new evidence of any cardiac concern,” White said.

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