NYU Langone Health researchers are co-leading a major clinical trial to determine whether the common antimalarial medication hydroxychloroquine can help prevent 2019 coronavirus disease (COVID-19) infections. The drug, marketed as Plaquenil®, has attracted considerable media attention, but definitive evidence is lacking on whether it can thwart infections in people who have been exposed to the novel coronavirus known as SARS-CoV-2.

The new study, which is being led by the University of Washington Medical Center in Seattle in collaboration with NYU Langone, may help answer that question. “Currently, there is no proven way to prevent COVID-19 after being exposed,” says Anna Bershteyn, PhD, assistant professor in the Department of Population Health at NYU Langone and the study’s co-principal investigator. “If hydroxychloroquine provides protection, then it could be an essential tool for fighting this pandemic. If it doesn’t, then people should avoid unnecessary risks from taking the drug.”

Hydroxychloroquine, used widely against malaria since the 1950s, is effective against autoimmune diseases like lupus and rheumatoid arthritis as well. Past research has suggested that the same drug might block the SARS-CoV-2 virus from invading human cells in a lab setting. Other modeling studies have hinted at the drug’s potential to prevent an infection or reduce the length of time that people shed viral particles and remain infectious. But these hypotheses have not been specifically tested in humans.

To do so, the new study is enrolling 2,000 adult volunteers at 6 sites. Specifically, researchers are recruiting people who lack any COVID-19 symptoms but have been in close contact with others who have a confirmed or pending diagnosis. On a random basis, the trial participants will receive either hydroxychloroquine or a placebo pill (vitamin C) every day for two weeks. Each day during the 14-day period and then again on day 28, the participants will swab their nasal passages and send the samples to researchers so they can detect any new COVID-19 infections.

If everything goes as planned, the eight-week trial could provide answers by summer on whether a preventive dose of the drug is safe and effective. If so, the strategy could give health officials a much needed boost in slowing person-to-person transmission.

The post-exposure prophylaxis (PEP) trial was inspired by similar efforts to prevent infections in people exposed to HIV. The $9.5 million study is being funded by the COVID-19 Therapeutics Accelerator, an initiative launched by the Bill & Melinda Gates Foundation in partnership with the Wellcome Trust and Mastercard to speed the identification and testing of potential treatments.

For more information, visit the COVID-19 PEP study website or call 1-855-NYU-PEP1 (1-855-698-7371).