The U.S. FDA has approved Merck's Keytruda Qlex, the first subcutaneously administered immune checkpoint inhibitor for solid tumors, enabling dosing in about one minute. This rapid administration format contrasts sharply with the traditional 30-minute intravenous infusion, potentially streamlining treatment sessions for the blockbuster anti-PD-1 therapy. This approval could further drive Keytruda's market dominance as a leading cancer immunotherapy with substantial annual sales.