Pfizer reports successful late-stage results for sasanlimab combo in bladder cancer

Pfizer has announced promising results from its phase 3 CREST trial, which is exploring the efficacy of sasanlimab as an induction therapy for certain bladder cancer patients. The study focused on individuals with BCG-naïve, high-risk non-muscle invasive bladder cancer (NMIBC), a condition where cancer cells remain within the bladder's inner lining. Each year, approximately 10,500 people in the UK are diagnosed with bladder cancer, and NMIBC constitutes the majority of these new cases.

Traditionally, NMIBC patients receive induction therapy using Bacillus Calmette-Guérin (BCG), followed by maintenance treatment. However, as many as 50% of high-risk NMIBC patients experience a recurrence of the disease, often necessitating radical cystectomy, a procedure fraught with substantial risks. The CREST trial assessed the subcutaneous administration of sasanlimab, an investigational anti-PD-1 monoclonal antibody, in combination with standard BCG treatment, both with and without continued maintenance.

The trial successfully met its primary endpoint, showing that sasanlimab combined with BCG led to a substantial and statistically significant improvement in event-free survival compared to BCG treatment alone. The safety profile of this drug combination was consistent with the known effects of BCG and the findings from previous clinical trials involving sasanlimab.

Roger Dansey, Pfizer’s chief oncology officer, highlighted the significance of these findings, stating that the initial treatment for high-risk NMIBC using BCG has seen little advancement over the past decades. He described the phase 3 CREST results as potentially transformative, marking the first significant therapeutic advance for BCG-naïve, high-risk NMIBC in over 30 years.

Pfizer plans to engage with global health authorities regarding these findings to support potential regulatory submissions for sasanlimab in treating this specific condition. The company also intends to continue researching the drug in combination with its antibody drug conjugate portfolio for use in advanced solid tumors.

This announcement follows another significant development for Pfizer. Three months earlier, Pfizer, in collaboration with its partner Astellas, received approval from the UK’s Medicines and Healthcare products Regulatory Agency for their product Padcev (enfortumab vedotin). This approval was in combination with Merck & Co's Keytruda (pembrolizumab) for treating advanced bladder cancer. Specifically, the UK regulator authorised the use of this antibody-drug conjugate and PD-1 inhibitor combination for adults with unresectable or metastatic urothelial carcinoma who are eligible for chemotherapy containing platinum.

These advancements underscore Pfizer's commitment to advancing the treatment landscape for bladder cancer patients and exploring innovative therapies that could offer significant benefits over existing treatment regimens. Through these efforts, Pfizer aims to address unmet needs in oncology, offering new hope to patients facing challenging diagnoses.