From COVID-19 antivirals to RSV, influenza, malaria, and gram-negative infections, new research highlights both advances and ongoing challenges in infectious disease prevention and treatment.
The US Food and Drug Administration (FDA) has accepted Shionogi’s new drug application for ensitrelvir, an investigational oral antiviral for the prevention of COVID-19 following exposure, with a Prescription Drug User Fee Act decision expected by June 16, 2026. The application is supported by phase 3 SCORPIO-PEP trial results, which demonstrated a 67% relative risk reduction in symptomatic COVID-19 compared with placebo (2.9% vs 9%; risk ratio, .33; 95% CI, .22-0.49; P < .0001), with consistent findings across broader analyses. Ensitrelvir, a SARS-CoV-2 main protease inhibitor marketed as Xocova in Japan and Singapore, was well tolerated with adverse events comparable to placebo and is also under regulatory review in Europe, Taiwan, and other regions. If approved, it would be the first oral antiviral available in the United States for postexposure prophylaxis of COVID-19.
