Pfizer and Astellas Pharma have shared positive results from a late-stage study of their antibody-drug conjugate Padcev (enfortumab vedotin-ejfv) in bladder cancer.
The phase 3 EV-302 trial, also known as KEYNOTE-A39, has been evaluating the drug in combination with Merck’s PD-1 inhibitor Keytruda (pembrolizumab) in patients with previously untreated locally advanced or metastatic urothelial cancer (UC).
Approximately 614,000 people are diagnosed with bladder cancer globally every year, with UC accounting for about 90% of all cases.
The Padcev/Keytruda combination was approved for UC by the Medicines and Healthcare products Regulatory Agency in October last year, following authorisations from the US Food and Drug Administration and European Commission.
The approvals were based on positive results from EV-302, in which Padcev plus Keytruda resulted in statistically significant and clinically meaningful improvements in overall survival (OS) and progression-free survival (PFS) compared to platinum-based chemotherapy.
The new data from an additional 12 months of follow-up, presented at this year’s American Society of Clinical Oncology Genitourinary Cancers Symposium, showed that the combination reduced the risk of death by 49% compared to chemotherapy, with a median OS of 33.8 months for the combination versus 15.9 months for chemotherapy.
Padcev plus Keytruda also reduced the risk of disease progression or death by 52% compared to chemotherapy and demonstrated a median PFS of 12.5 months versus 6.3 months for chemotherapy, according to the latest results.
The companies added that the OS benefit was seen in all pre-specified patient subgroups, including cisplatin eligible and ineligible cohorts, and the safety profile of the combination was consistent with previous findings.
Pfizer’s chief oncology officer, Roger Dansey, said: “Patients with bladder cancer can face a poor prognosis, particularly in the advanced stages, and until recently had few available treatment options.
“The updated EV-302 results show sustained long-term efficacy in a broad population that includes both cisplatin eligible and ineligible patients and reinforce this combination’s ability to reshape the UC treatment landscape.”
Also commenting on the latest results, Ahsan Arozullah, senior vice president, head of oncology development at Astellas, said: “The combination of [Padcev] and [Keytruda] was the first approval to offer an alternative to platinum-containing chemotherapy, which had been the standard of care for first-line locally advanced or metastatic UC for decades.
“We are delighted that the additional follow-up results of the EV-302 trial show a durable benefit.”