Pfizer's Bladder Cancer Breakthrough: Sasanlimab Plus BCG Prolongs Event-Free Survival

Pfizer Inc. (NYSE: PFE) has revealed encouraging data from its pivotal Phase 3 CREST trial, evaluating sasanlimab, an investigational anti-PD-1 monoclonal antibody, in combination with Bacillus Calmette-Guérin (BCG) as induction therapy with or without maintenance in patients with BCG-naïve, high-risk non-muscle invasive bladder cancer (NMIBC). The study met its primary endpoint, demonstrating a clinically meaningful and statistically significant improvement in event-free survival (EFS) with sasanlimab in combination with BCG compared to BCG alone.

The CREST trial enrolled 814 patients with high-risk NMIBC who had not previously received BCG. Participants were randomly assigned to one of three treatment arms: sasanlimab plus BCG induction and maintenance (Arm A), sasanlimab plus BCG induction only (Arm B), or BCG induction and maintenance alone (Arm C). The primary endpoint was investigator-assessed EFS between Arm A and Arm C, defined as the time from randomization to the earliest of recurrence of high-grade disease, progression of disease, persistence of carcinoma in situ (CIS), or death.



Pfizer announced that the combination of sasanlimab and BCG significantly improved EFS compared to BCG alone, meeting the primary endpoint of the trial. The safety profile of sasanlimab in combination with BCG was generally consistent with the known profile of BCG and data reported from clinical trials with sasanlimab, indicating that the combination is well-tolerated.

"This is a significant milestone for patients with BCG-naïve, high-risk NMIBC, as the initial therapy with BCG has not advanced in decades," said Roger Dansey, M.D., Chief Oncology Officer at Pfizer. "These results reinforce Pfizer's leadership in genitourinary cancer research and development, demonstrating our ongoing commitment to deliver new treatment options for patients with bladder cancer."

The CREST trial's results suggest a potential paradigm shift in the treatment of BCG-naïve, high-risk NMIBC, offering prolonged event-free survival and reducing the need for more aggressive treatment options. The combination of sasanlimab and BCG could become the new standard of care for this patient population, providing a much-needed advancement in the field after decades of stagnation.

Pfizer plans to present the data at an upcoming medical congress and discuss the findings with global health authorities to support potential regulatory filings for sasanlimab. If approved, sasanlimab would be the first PD-1 inhibitor in combination with BCG to significantly prolong event-free survival in treatment-naive high-risk NMIBC.

In conclusion, Pfizer's pivotal Phase 3 CREST trial has demonstrated the potential of sasanlimab in combination with BCG to significantly improve event-free survival in patients with BCG-naïve, high-risk NMIBC. This breakthrough could lead to a new standard of care for this patient population and provide much-needed hope for those affected by this disease.