MRK HIV Regimen Meets Goal in New Study, Gains EU Nod for Keytruda SC

Core Insights - Merck announced positive top-line results from a pivotal late-stage study for its investigational HIV treatment DOR/ISL, demonstrating non-inferiority to Gilead's Biktarvy [1][4][6] Group 1: Study Results - The phase III MK-8591A-053 study evaluated DOR/ISL in treatment-naïve adults with HIV-1, showing comparable efficacy and safety to Gilead's Biktarvy [3][4] - The study met its primary endpoint, with a significant percentage of patients achieving HIV-1 RNA levels below 50 copies/mL at week 48 [4][8] - DOR/ISL's safety profile was found to be similar to that of Biktarvy, supporting its potential as a treatment option [4][8] Group 2: Regulatory and Market Implications - A regulatory filing for DOR/ISL to treat virologically suppressed adults on antiretroviral therapy is under FDA review, with a decision expected on April 28, 2026 [2] - Merck plans to present detailed results from the MK-8591A-053 study at a future medical conference and is preparing applications for approval to treat treatment-naïve HIV patients [5][6] - Year-to-date, Merck's shares have decreased by 4.4%, contrasting with the industry's growth of 14.5% [5] Group 3: Additional Developments - The European Commission approved the subcutaneous formulation of Keytruda, enhancing patient convenience and potentially increasing adoption rates [10][12] - The SC version of Keytruda can be administered in as little as one minute, compared to at least 30 minutes for the IV formulation, easing the burden on healthcare facilities [12][13]