FDA Approves ArkBio Ziresovir Phase II Trial

Mapp Biopharmaceutical Co., Ltd. (ArkBio) announced that the U.S. United States — Food and Drug Administration (FDA) has approved ziresovir (AK0529) for a phase II clinical trial in severely ill RSV-infected infants, including those in pediatric intensive care units (PICU). Ziresovir is the first direct RSV antiviral to complete a phase III trial with positive results, showing significant reduction in viral load, faster resolution of respiratory symptoms, and lower risk of recurrent wheezing and asthma. The new phase II trial is a multicenter, randomized, double-blind, placebo-controlled study focusing on the most critically ill RSV patients, evaluating clinical efficacy, particularly length of oxygen treatment and sustained recovery time. This approval marks a key milestone in the global clinical development of ziresovir, addressing an urgent unmet need as no RSV-specific antiviral is currently approved worldwide. ArkBio, a commercial-stage biotech focused on respiratory and pediatric diseases, has partnerships with Roche, F. Hoffmann-La Roche — Genentech, Scripps Research, the China — Chinese Academy of Sciences, and Qilu Pharmaceutical.