[Edaily Reporter KIM SAE-MI ] "Keytruda SC," which incorporates subcutaneous (SC) formulation technology from Alteogen Inc.(196170), has had its indication expanded in Europe to include the treatment of muscle-invasive bladder cancer.

Merck (MSD) of the U.S., a partner of Alteogen Inc., announced in a press release on the 21st (local time) that the European Commission (EC) has approved the combination therapy of the immunotherapy “Keytruda” and the antibody-drug conjugate (ADC) “Padseve” for pre- and post-surgical treatment of adult patients with operable muscle-invasive bladder cancer.

This approval covers not only the intravenous (IV) formulation of Keytruda but also Keytruda SC, which incorporates Alteogen Inc.’s technology. In the United States, Keytruda SC is marketed under the brand name “Keytruda Qlex.”

With this approval, the Keytruda plus Padseve combination therapy can now be used regardless of whether cisplatin-based chemotherapy is feasible. This is the first PD-1 inhibitor and ADC combination therapy approved in Europe regardless of eligibility for cisplatin treatment.

This approval was based on the results of the Phase 3 “KEYNOTE-B15” (EV-304) clinical trial, conducted jointly by MSD, Pfizer, and Astellas. The trial enrolled 808 patients with muscle-invasive bladder cancer who were eligible for cisplatin-based chemotherapy.

The trial results showed that the Keytruda plus Padseve combination group had a 47% lower risk of events related to event-free survival (EFS)—including disease progression, recurrence, and death—compared to the control group, which had received standard neoadjuvant chemotherapy and surgery. The risk of death was reduced by 35%, and the pathological complete response (pCR) rate was 55.8% in the combination group and 32.5% in the control group.

Margery Green, Senior Vice President at MSD, stated, “We are pleased to have received additional approval in Europe for the combination of Keytruda and Padseve in less than six months,” adding, “This approval allows us to offer treatment options to more patients with muscle-invasive bladder cancer, regardless of their eligibility for cisplatin.”

Previously, in June, MSD received approval in Europe for the combination therapy of Keytruda and Padseve for patients with muscle-invasive bladder cancer who are ineligible for cisplatin-based chemotherapy. This latest approval expands the treatment population to include patients who are eligible for cisplatin.

Keytruda SC incorporates Alteogen Inc.’s human hyaluronidase “ALT-B4.” This technology enables the administration of antibody drugs—which are typically administered via intravenous injection—as subcutaneous injections.

This approval for the expanded indication applies to the 27 member states of the European Union (EU), as well as Iceland, Liechtenstein, and Norway.