Penn Medicine finds hydroxychloroquine ineffective in preventing COVID-19

Hydroxychloroquine is no more effective than a placebo in preventing COVID-19, researchers at the Perelman School of Medicine found.

There was no difference in infection rates among health care workers who took the drug daily and those who took a placebo, according to Penn Medicine News. The study was published on Sept. 30 in the Journal of the American Medical Association: Internal Medicine.

A placebo is a medical treatment designed to deceive a participant in a clinical experiment because it does not contain any active ingredients.

While the researchers did not see an effect associated with HCQ, overall infection rates remained low among participants, Penn Medicine News reported. The researchers believe this is the result of the effectiveness of other prevention methods, such as social distancing, use of personal protective equipment, and proper hand hygiene. 

The study included 125 health care workers from the Hospital of the University of Pennsylvania and Penn Presbyterian Medical Center, including the emergency departments and COVID-19 units.

Associate professor of medicine Ravi Amaravadi and professor of emergency medicine Benjamin Abella led the clinical trials. Between April 9 and July 14, roughly half of the participants received HCQ and roughly half received a matching placebo. 

At the end of the study, 6.3% of those who took HCQ tested positive and 6.6% of those who took the placebo tested positive. There was also no difference detected in the heart rhythms of either group, which showed that while the drug did not prevent against COVID-19, it was not detrimental aside from temporary side effects, Penn Medicine News reported.

“To really test the potential of HCQ as a prevention drug, we felt it was key to recruit health care workers with many hours of direct physical exposure to COVID-19 patients, then randomize them in a double-blind manner between hydroxychloroquine or a matching placebo, and treat them for a long period of time,” Amaravadi told Penn Medicine News.

At the start of the pandemic, studies suggested HCQ — which is used to treat arthritis and malaria — could be an effective treatment for COVID-19, but follow-up studies have found less promising results, The New York Times reported.

The drug gained national prominence in March when President and 1968 Wharton graduate Donald Trump tweeted about it as a potential COVID-19 treatment. Trump, who announced he tested positive for the virus on Friday, announced in May that he was taking the drug.

“A lot of good things have come out. You’d be surprised at how many people are taking it, especially the front line workers,” Trump said at the White House. "I happen to be taking it."