Keytruda Qlex is an FDA-approved subcutaneous formulation of Keytruda developed by Merck & Co. It contains the active immunotherapy molecule pembrolizumab, a PD-1 immune checkpoint inhibitor, combined with berahyaluronidase alfa, an enzyme that enables rapid subcutaneous delivery.

Unlike the traditional intravenous (IV) infusion of Keytruda administered over 30 minutes, Keytruda Qlex is given as a 1- or 2-minute subcutaneous injection every 3 or 6 weeks. Clinical studies in advanced non–small cell lung cancer (NSCLC) demonstrated comparable drug exposure and consistent safety between Keytruda Qlex and IV Keytruda, offering patients a faster administration option while maintaining therapeutic effectiveness.