Newsroom

Hydroxychloroquine has been widely administered to COVID-19 patients but without robust evidence supporting its use. Recent laboratory studies (1 and 2) suggested that hydroxychloroquine may prevent the SARS-CoV-2 virus from replicating in mammalian cells. Data from small clinical studies have been difficult to interpret.

What’s different about this study

The study included nearly 1,400 patients and is currently the largest published study of hydroxychloroquine in COVID-19 patients. Previous studies have included no more than 100 patients.

What the study did

The study included the first 1,376 patients hospitalized with COVID-19 at a large medical center in New York City (excluding patients who were discharged, intubated, or died within 24 hours of arriving at the emergency department). Among these patients, 811 (58.9%) received hydroxychloroquine and 565 patients (41.1%) did not. The researchers examined the relationship between hydroxychloroquine use and the development of respiratory failure that led to intubation or death. Overall, 346 patients developed respiratory failure; 180 were intubated and 166 died without intubation. After using established and sophisticated statistical techniques to account for known differences between patients in the two groups, including age, sex, and initial vital signs, the researchers found that patients who received hydroxychloroquine had the same risk of intubation or death as patients who did not receive the drug.

What the study means

Hospitalized patients with COVID-19 illness should not be routinely treated with hydroxycholoroquine.

“Given the observational design of the study, our results cannot completely exclude the possibility of either modest benefit or harm of hydroxychloroquine treatment, but the findings do not support its use outside of randomized clinical trials,” says Neil Schluger, MD, chief of the Division of Pulmonary, Allergy and Critical Care Medicine at NewYork-Presbyterian/Columbia University Irving Medical Center and professor of medicine, environmental health sciences, and epidemiology at Columbia University Vagelos College of Physicians and Surgeons, and corresponding author of the paper. “A randomized controlled trial is the best way to determine if a drug has a benefit, and we support enrolling patients with COVID-19 into such trials,” Schluger says. “There are currently many such studies of hydroxychloroquine that are planned or already enrolling in the United States and elsewhere.”

More Information

The study, titled “Observational study of hydroxychloroquine in hospitalized patients with COVID-19,” was published online May 7 in the New England Journal of Medicine. Other authors: Joshua Geleris, Yifei Sun, Jonathan Platt, Jason Zucker, Matthew Baldwin, George Hripcsak, Angelena Labella, Daniel Manson, Christine Kubin, R. Graham Barr, and Magdalena Sobieszczyk (all from NewYork-Presbyterian/Columbia University Irving Medical Center). The research was supported in part by the following grants from the National Institutes of Health: RO1-LM006910, RO1-HL077612, RO1-HL093081 and RO1-HL121270.