Pfizer's Sasanlimab and BCG Enhance Event-Free Survival in High-Risk Bladder Cancer

Pfizer Inc. recently revealed promising results from its Phase 3 CREST trial, investigating the efficacy of sasanlimab, an experimental anti-PD-1 monoclonal antibody, combined with Bacillus Calmette-Guérin (BCG) therapy. This study focused on patients with high-risk, BCG-naïve, non-muscle invasive bladder cancer (NMIBC). The trial achieved its primary goal, event-free survival (EFS) as assessed by investigators, showcasing a significant and clinically relevant improvement when sasanlimab was used alongside BCG compared to BCG alone.

Dr. Neal Shore, Medical Director for the Carolina Urologic Research Center and lead investigator, emphasized the high recurrence and progression rates in patients with this form of bladder cancer. He highlighted the potential of sasanlimab, noting its ability to extend event-free survival, possibly delaying or reducing the need for more invasive treatments. If approved, sasanlimab could be administered subcutaneously every four weeks, offering a less burdensome treatment option for patients and healthcare systems alike.

Bladder cancer impacts approximately 100,000 individuals worldwide annually, with BCG therapy being the standard treatment for decades. Nonetheless, 40-50% of patients experience recurrence, often necessitating radical cystectomy, a procedure carrying significant risks. Bladder-sparing alternatives remain limited.

Dr. Roger Dansey, Pfizer's Chief Oncology Officer, described the trial outcomes as potentially transformative, marking the first significant advancement in BCG-naïve, high-risk NMIBC treatment in over 30 years. The results underscore Pfizer’s dedication to advancing genitourinary cancer treatments and providing new options for bladder cancer patients.

The safety profile of sasanlimab combined with BCG aligned with known data from BCG and existing trials involving sasanlimab. Its safety characteristics were broadly consistent with other PD-1 inhibitors. Pfizer anticipates presenting the findings at an upcoming medical congress and intends to engage with global health authorities to discuss potential regulatory submissions. Sasanlimab is also being tested in combination with Pfizer’s antibody-drug conjugate (ADC) portfolio for advanced solid tumors.

The CREST trial is a Phase 3, international, open-label study with three parallel arms, contrasting sasanlimab and BCG therapy (with or without maintenance) against BCG therapy alone in patients with BCG-naïve, high-risk NMIBC. Participants received 300 mg of sasanlimab via subcutaneous injection every four weeks, coupled with BCG for six weeks during the induction phase. This was followed by either maintenance with BCG or no further BCG, depending on the study arm. Primary and secondary outcomes focused on event-free survival, assessing various disease progression metrics.

Sasanlimab operates as a humanized immunoglobulin G4 monoclonal antibody, targeting PD-1, a protein that modulates immune response. Through its action, sasanlimab potentially enhances the body's ability to fight tumors. Previously demonstrated efficacy in early clinical trials for advanced cancers has prompted ongoing research in combination therapies across multiple cancer types.

Within Pfizer Oncology, substantial efforts are directed toward revolutionizing cancer therapy. Their robust portfolio includes diverse treatment strategies, such as small molecules, ADCs, and bispecific antibodies, focusing on prevalent cancers like breast and lung cancer. Guided by scientific innovation, Pfizer is committed to delivering groundbreaking therapies that improve the quality and longevity of life for cancer patients.

In a broader context, Pfizer aims to harness scientific and global resources to develop treatments that significantly enhance patient lives. The company maintains rigorous standards in creating healthcare products and collaborates with various stakeholders to increase access to affordable healthcare worldwide. With a longstanding history of 175 years, Pfizer continues to impact the lives of countless individuals relying on their innovations.