Merck, known as MSD outside of the United States and Canada, announced that the European Commission (EC) has approved a new subcutaneous (SC), or under the skin, route of administration and a new pharmaceutical form (solution for injection) of Keytruda (pembrolizumab), Merck’s anti-PD-1 therapy. 

Keytruda SC, as it will be marketed in the European Union (EU), [known as Keytruda Qlextm (pembrolizumab and berahyaluronidase alfa-pmph) in the U.S.], is a subcutaneous injection containing pembrolizumab and berahyaluronidase alfa and has been approved for use across all 33 Keytruda indications for adult patients in Europe. 

Berahyaluronidase alfa is a variant of human hyaluronidase developed and manufactured by Alteogen Inc. For a list of select indications for which Keytruda and Keytruda Qlex are approved in the United States, see Selected Indications in the U.S. below.

The approval of Keytruda SC is based on results from the pivotal 3475A-D77 trial, which compared Keytruda SC and Keytruda, both administered every six weeks, each in combination with chemotherapy, in patients with treatment naïve metastatic non-small cell lung cancer (NSCLC) with no EGFR, ALK, or ROS1 genomic tumor aberrations.

This trial demonstrated comparable pharmacokinetic exposure levels between Keytruda SC and Keytruda. In descriptive efficacy analyses, overall response rates (ORR) were consistent between Keytruda SC and Keytruda. 

The ORR in the Keytruda SC with chemotherapy arm was 45% (95% CI, 39-52) and 42% (95% CI, 33-51) in the Keytruda with chemotherapy arm. Additionally, no notable differences were observed in progression-free survival (PFS) and overall survival (OS).

This decision authorizes the marketing of Keytruda SC in all 27 EU member states, as well as Iceland, Liechtenstein, and Norway.

This follows Keytruda Qlex’s approval by the U.S. FDA in September 2025. In the U.S, Keytruda Qlex is now approved for use in adults across all solid tumor indications approved for Keytruda.