WHO Pauses Hydroxychloroquine Arm of COVID-19 Study Following Safety Concerns


Questions over the efficacy and safety of hydroxychloroquine continue to be raised following the World Health Organization’s decision to temporarily halt a study of the malaria drug as a potential treatment for COVID-19.

The WHO decision was made following a report published in The Lancet medical journal on Friday that showed COVID-19 patients who received the medication in the study were dying at a higher rate than other patients with the disease caused by the novel coronavirus. The study showed that among patients who received hydroxychloroquine, either alone or with a macrolide, the study authors estimated a higher mortality rate. COVID-19 patients who were seriously ill and who were treated with hydroxychloroquine or chloroquine were more likely to die or develop dangerous irregular heart rhythms, the study authors said.

Following that report, the WHO’s executive group overseeing the Solidarity trial, the multi-country study assessing hydroxychloroquine against COVID-19, agreed to temporarily halt the assessment of the malaria drug while it reviews the Lancet study and other evidence that has been gathered globally. The WHO Solidarity trial included 3,550 patients from more than 17 countries, who were randomly assigned to receive hydroxychloroquine or three other medications being assessed for the treatment of COVID-19.

“The review will consider data collected so far in the Solidarity Trial and in particular robust randomized available data, to adequately evaluate the potential benefits and harms from this drug,” WHO Director-General Tedros Adhanom Ghebreyesus said during a presentation this weekend.

Tedros noted that only the hydroxychloroquine arm of the Solidarity study is being paused. The other arms of the study will continue as the Independent Data Monitoring Committee reviews the safety data from the study. Tedros noted that the drug has been safe and effective in patients with malaria and autoimmune diseases such as lupus, but in COVID-19 patients, safety concerns have been raised by multiple studies.

“This concern relates to the use of hydroxychloroquine and chloroquine in COVID-19. WHO will provide further updates as we know more. And we will continue to work night and day for solutions, science and solidarity,” Tedros said, according to a transcript of his remarks.

Speaking to NPR, WHO chief scientist Soumya Swaminathan reiterated that the review of hydroxychloroquine was sparked by the concerns raised in the trial reported in the Lancet. Swaminathan noted that that study was not a randomized control trial but still large enough to raise concern.

"While it was still a reporting of observational data, it came from multiple registries and quite a large number of patients, 96,000 patients,” Swaminathan said. “We decided we should be proactive, err on the side of caution and suspend enrollment temporarily into the hydroxychloroquine arm.”

If all goes well, the hydroxychloroquine arm could resume within a couple of weeks, Swaminathan said.

The safety concerns regarding hydroxychloroquine in COVID-19 patients raised in the Lancet study are not the first time these issues have been noted. A study in China showed that not only did hydroxychloroquine not help patients clear the virus better than standard care, the drug was also likely to cause serious harm. A trial in Brazil was also halted due to safety concerns.

Earlier this month, another study conducted in New York raised questions, not about the safety of hydroxychloroquine, but the efficacy in COVID-19. That research, published in The New England Journal of Medicine, showed that although the drug was widely administered to COVID-19 patients, the results did not show “robust evidence” to warrant continued use.

While these concerns have been raised, there is still some anecdotal evidence that shows the drug has been able to effectively treat COVID-19 patients. The drug has been widely hailed by President Donald Trump who said he had been taking the medication for about two weeks as a preventative measure against the novel coronavirus.

Back to news