THURSDAY, June 4, 2020 (HealthDay News) -- For individuals with high- or moderate-risk exposure to COVID-19, postexposure prophylaxis with hydroxychloroquine does not prevent illness compatible with COVID-19, according to a study published online June 3 in the New England Journal of Medicine.
David R. Boulware, M.D., M.P.H., from the University of Minnesota in Minneapolis, and colleagues conducted a randomized trial across the United States and Canada testing hydroxychloroquine as postexposure prophylaxis for COVID-19. Adults with household or occupational high- or moderate-risk exposure were randomly assigned to receive either placebo or hydroxychloroquine within four days after exposure.
A total of 821 asymptomatic participants were enrolled. The researchers found that 87.6 percent of the participants reported a high-risk exposure. There was no significant difference seen in the incidence of new illness compatible with COVID-19 for those receiving hydroxychloroquine or placebo (11.8 versus 14.3 percent; absolute difference, −2.4 percent; 95 percent confidence interval, −7.0 to 2.2; P = 0.35). Compared with placebo, side effects were more common with hydroxychloroquine (40.1 versus 16.8 percent); however, there were no reports of serious adverse reactions.
"This randomized trial did not demonstrate a significant benefit of hydroxychloroquine as postexposure prophylaxis for COVID-19. Whether preexposure prophylaxis would be effective in high-risk populations is a separate question, with trials ongoing," the authors write. "In order to end the pandemic, a reduction in community transmission is needed."