The US Food and Drug Administration (FDA) has granted breakthrough therapy designation for Astellas and Seattle Genetics’ jointly developed PADCEV (enfortumab vedotin-ejfv), in combination with KEYTRUDA (pembrolizumab), to treat a type of bladder cancer.

Developed by US-based pharma firm Merck, KEYTRUDA is a humanized antibody that works by blocking the PD-1 pathway and is used as an immunotherapy for treating cancers.

The combination of PADCEV and KEYTRUDA is indicated as a treatment for unresectable metastatic urothelial cancer in patients not treated with cisplatin-based chemotherapy in the first-line setting.

Astellas senior vice president and oncology therapeutic area head Andrew Krivoshik said: “The FDA’s Breakthrough Therapy designation reflects the encouraging preliminary evidence for the combination of PADCEV and pembrolizumab in previously untreated advanced urothelial cancer to benefit patients who are in need of effective treatment options.

“We look forward to continuing our work with the FDA as we progress our clinical development program as quickly as possible.”

The FDA breakthrough therapy designation for PADCEV is based on ongoing EV-103 trial

The FDA has granted breakthrough therapy designation based on results from the dose-escalation cohort and expansion cohort A of the phase 1b/2 trial, EV-103, which evaluated PADCEV in combination with KEYTRUDA.

EV-103 is an ongoing, multi-cohort, open-label, multicentre phase 1b/2 trial of PADCEV, evaluating the safety, tolerability and efficacy in muscle-invasive, locally advanced and metastatic urothelial cancer.

In December 2019, PADCEV has been granted the FDA accelerated approval for the treatment of metastatic urothelial cancer in patients previously treated using PD-1/L1 inhibitor and platinum-containing chemotherapy.

Seattle Genetics chief medical officer Roger Dansey said: “This is an important step in our investigation of PADCEV in combination with pembrolizumab as a first-line therapy for patients with advanced urothelial cancer who are unable to receive cisplatin-based chemotherapy.

“Based on encouraging early clinical activity, we recently initiated a phase 3 trial of this platinum-free combination and look forward to potentially addressing an unmet need for patients.”