The new approvals for the anti-programmed death-1 (PD-1) therapies cover both neoadjuvant (pre-surgery) and adjuvant (post-surgery) treatment and apply to patients regardless of their eligibility for cisplatin.
These decisions are based on findings from the Phase III KEYNOTE-B15 trial, also known as EV-304, and build on an earlier authorisation linked to the Phase III KEYNOTE-905 (EV-303) trial.
KEYNOTE-B15 enrolled 808 patients and compared the combination of pembrolizumab and enfortumab vedotin-ejfv with standard neoadjuvant chemotherapy and surgery.
The combination demonstrated a 47% reduction in the risk of event-free survival (EFS) events among patients eligible for cisplatin-based chemotherapy, compared to chemotherapy plus surgery.
Median EFS was not reached for perioperative pembrolizumab plus enfortumab vedotin-ejfv. The regimen also showed a 35% reduction in risk of death compared to chemotherapy and surgery.
In addition, patients in the experimental arm had a higher rate of pathologic complete response (55.8%) compared to those receiving chemotherapy (32.5%).
MSD Research Laboratories senior vice-president and global clinical development oncology head Dr Marjorie Green said: “We’re expanding the use of Keytruda and Keytruda Qlex, each in combination with Padcev, for patients with muscle-invasive bladder cancer who are eligible for cisplatin-based chemotherapy with these approvals.
“The results from KEYNOTE-B15, together with KEYNOTE-905, highlight the potential of these new treatment options for patients regardless of cisplatin eligibility in the perioperative setting and mark a promising step forward in the treatment of muscle-invasive bladder cancer.”
Permanent discontinuation of pembrolizumab in the neoadjuvant phase due to adverse reactions occurred in 17% of patients, with reported serious reactions that included rash, pneumonitis/interstitial lung disease, and diarrhoea.
Fatal adverse reactions occurred in 1.7% of patients in the neoadjuvant phase and 3.2% in the adjuvant phase.
Last month, the European Commission (EC) approved MSD’s Keytruda in combination with Padcev as a neoadjuvant treatment for MIBC.