Health and Medicine

The WHO Halts Hydroxychloroquine Trial Over Patient Safety Fears


Tom Hale

Senior Journalist

clockMay 26 2020, 12:21 UTC

There has recently been a huge amount of hype surrounding hydroxychloroquine, despite the lack of scientific evidence that proves its benefits for treating Covid-19. Simone Hogan/Shutterstock

The World Health Organization (WHO) has paused its global trial of hydroxychloroquine – the anti-malaria drug Donald Trump has controversially promoted and claimed he's taking as a precaution – after new research suggested the drug could increase the risk of death in Covid-19 patients. 


Speaking on Monday, the WHO’s Director-General Dr Tedros Adhanom Ghebreyesus said the organization has implemented a temporary pause of its hydroxychloroquine trial from the Solidarity Trial, a global project involving hundreds of hospitals across several countries that are investigating several possible treatments for Covid-19, while researchers review the safety of the drug for this treatment. Dr Tedros stressed that the drug is still considered safe for the treatment of malaria and autoimmune diseases for which it was developed.

“The Executive Group has implemented a temporary pause of the hydroxychloroquine arm within the Solidarity Trial while the safety data is reviewed by the Data Safety Monitoring Board,” Dr Tedros said at a media briefing on Monday. 

“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.” 

The decision, Dr Tedros said, comes off the back of a landmark study published in The Lancet medical journal on May 22 that analyzed data from nearly 15,000 patients with Covid-19 receiving a combination of chloroquine, hydroxychloroquine, and/or antibiotics. It concluded there was “no evidence of benefit” of the treatment for patients with Covid-19 from the drug combinations. In fact, seriously ill Covid-19 patients who were treated with hydroxychloroquine and chloroquine were significantly more likely to die. This echoes the findings of a US Veterans Health Administration study released in April that also found a higher risk of death among patients treated with hydroxychloroquine alone.


Hydroxychloroquine is listed by the WHO as an essential medicine because it is widely used to prevent and treat malaria in areas where malaria remains sensitive to chloroquine. It's also used as a treatment for certain autoimmune diseases, such as lupus. There has recently been a huge amount of hype surrounding hydroxychloroquine and chloroquine as a treatment for Covid-19, despite the lack of scientific evidence that proves its benefits. Much of the fanfare around the drugs stems from President Trump's promotions at press briefings and on social media, based on a small French study published in the International Journal of Antimicrobial Agents in March. Studying 36 patients, they found that hydroxychloroquine was “significantly associated” with a reduction in viral load in Covid-19 patients. 

However, the research has since run into a fair amount of criticism and a number of other studies have not reached the same conclusion, finding the drugs have no benefit for patients with Covid-19. Other research highlighted concerns over the potential side-effects of the drug when treating severely ill Covid-19 patients, most notably potentially fatal irregular heartbeats.

In spite of the scant evidence that they work as a treatment for those infected with Covid-19, the drugs caught the attention of President Trump, who recently revealed at a press conference he is taking hydroxychloroquine and azithromycin to ward off the virus, despite the lack of evidence that they act as a preventative against catching Covid-19 either. 


"What do you have to lose? I've been taking it for about a week and a half,” Trump said at the roundtable event at the White House on May 18. “I take it because I hear very good things.”

Health and Medicine
  • pandemic,

  • outbreak,

  • World Health Organization,

  • drug,

  • coronavirus,

  • covid-19,

  • chloroquine,

  • hydroxychloroquine,

  • drug trial