World Health Organization temporarily halts hydroxychloroquine trials

The World Health Organization says it is temporarily dropping hydroxychloroquine — the malaria drug U.S. President Donald Trump said he was taking — from its global study into experimental COVID-19 treatments.

In a press briefing on Monday, WHO Director General Tedros Adhanom Ghebreyesus said in light of a paper published last week in the Lancet that suggested people taking hydroxychloroquine were at higher risk of death and heart problems, there would be "a temporary pause" on the hydroxychloroquine arm of its global clinical trial.

"This concern relates to the use of hydroxychloroquine and chloroquine in COVID-19," said Tedros, who pointed out the drugs are approved treatments for malaria and some autoimmune diseases.

Other treatments in the trial, including the experimental drug remdesivir and an HIV combination therapy, are still being tested.

Tedros said the executive group behind the WHO's global SOLIDARITY trial met on Saturday and decided to conduct a comprehensive review of all available data on hydroxychloroquine and suspend its use in the trial.

Canada is part of the Solidarity trials, known in this country as CATCO (Canadian Treatments for COVID-19). Patients requiring hospitalization for COVID-19 at one of 20 participating Canadian hospitals are eligible to take part. 

Dr. Michael Ryan, WHO's emergencies chief, said there was no indication of any safety problems with hydroxychloroquine in the WHO trial to date, but that statisticians would now analyze the information.

"We're just acting on an abundance of caution based on the recent results of all the studies to ensure that we can continue safely with that arm of the trial," he said.

The WHO said it expected to have more details within the next two weeks.

Last week, Trump announced he was taking hydroxychloroquine despite not having tested positive for the coronavirus.

Both the European Medicines Agency and the U.S. Food and Drug Administration warned health professionals last month that the drug should not be used to treat COVID-19, the illness caused by the coronavirus, outside of hospital or research settings due to numerous serious side-effects that in some cases can be fatal.

Hydroxychloroquine and chloroquine are approved for treating lupus and rheumatoid arthritis and for preventing and treating malaria, but no large rigorous tests have found them safe or effective for preventing or treating COVID-19.