Pfizer Inc. has announced new clinical study results for HYMPAVZI, a treatment for adults and adolescents with hemophilia A or B who have developed inhibitors. The findings, presented at the 67th American Society of Hematology $(ASH)$ Annual Meeting and Exposition in Orlando and published in Blood, demonstrated that HYMPAVZI significantly reduced bleeding episodes and improved certain aspects of health-related quality of life with once-weekly subcutaneous administration. The safety profile was generally favorable, with no deaths or thromboembolic events reported; the most common adverse events included COVID-19, upper respiratory tract infection, fibrin D-dimer increase, and headache, mostly mild or moderate in severity. Pfizer has submitted these data to the U.S. Food and Drug Administration and European Medicines Agency for review. HYMPAVZI is currently approved in more than 40 countries for patients aged 12 years and older with hemophilia A or B without inhibitors.