Merck Wins FDA Approval for Subcutaneous Keytruda as Exclusivity Challenges Approach
The FDA has approved a subcutaneously injected version of Merck's top-selling immunotherapy drug, Keytruda, named Keytruda Qlex, for use in adults and children aged 12 and older with 38 solid tumor indications—matching most of those covered by the intravenous version246.
Keytruda Qlex combines pembrolizumab with the enzyme berahyaluronidase alfa-pmph, enabling subcutaneous administration in a one-minute injection every three weeks or a two-minute injection every six weeks, compared to a 30-minute infusion for the original drug24.
This new injectable formulation does not require patients to go to a traditional infusion center, but it must still be administered by a healthcare professional at a clinical care site2.
The approval is based on a Phase 3 trial showing that the exposure, overall response rate (45% for Qlex vs. 42% for IV Keytruda), progression-free survival, and safety profile of the subcutaneous form were comparable to the original intravenous Keytruda2.
Keytruda generated $15.1 billion in sales in the first half of 2025, but faces U.S. patent expirations in 2028, after which biosimilar competitors are expected; the new Qlex formulation could help Merck retain market share as exclusivity ends21.
Keytruda Qlex is the latest subcutaneous checkpoint inhibitor to hit the market after recent approvals of other injectable immunotherapies, including Roche's Tecentriq and Bristol Myers Squibb's Opdivo2.
Sources:
1. https://www.fiercepharma.com/pharma/merck-scores-fda-approval-subcutaneous-keytruda
2. https://medcitynews.com/2025/09/mercks-injectable-version-of-blockbuster-cancer-drug-keytruda-wins-fda-approval/
4. https://www.fda.gov/drugs/resources-information-approved-drugs/fda-approves-pembrolizumab-and-berahyaluronidase-alfa-pmph-subcutaneous-injection
6. https://www.clinicaloncology.com/Lung-Cancer/Article/09-25/Keytruda-Qlex-Approved-for-Subcutaneous-Injection-for-Solid-Tumor-Indications-Approved-for-IV-Pembrolizumab/78327