British-Swedish biopharmaceutical company AstraZeneca (NASDAQ:AZN) reported on Friday that Imfinzi (durvalumab), combined with Bacillus Calmette-Guérin (BCG) induction and maintenance therapy, significantly improved disease-free survival (DFS) in patients with high-risk non-muscle-invasive bladder cancer (NMIBC) in the Phase III POTOMAC trial.

The data showed that adding one year of Imfinzi to standard-of-care BCG induction and maintenance therapy significantly improved DFS compared to BCG alone.

This treatment plan resulted in patients living longer without high-risk disease recurrence or progression, with no new safety concerns identified. The combination did not hinder patients' ability to complete BCG therapy, and its safety profile remained consistent with known data for both medicines.

The trial included a second experimental arm testing Imfinzi with BCG induction-only therapy, which did not meet its DFS endpoint. While the study was not powered to assess overall survival, descriptive data showed no negative impact, AstraZeneca said.

NMIBC accounts for over 70% of bladder cancer diagnoses with approximately half of these cases being considered high-risk for recurrence or progression. Despite efforts to cure, recurrence is common, with many patients ultimately requiring bladder surgery.

These findings, which will be presented at an upcoming medical meeting, support AstraZeneca's broader strategy to extend immunotherapy into earlier stages of bladder cancer. The company continues to develop Imfinzi for early and late-stage bladder cancer in the VOLGA and NILE studies. Imfinzi is already approved for muscle-invasive bladder cancer in multiple countries based on NIAGARA trial data.