The U.S. Food and Drug Administration (FDA) has approved a new treatment option for patients with high-risk non–muscle invasive bladder cancer (NMIBC), authorizing the use of durvalumab (Imfinzi) in combination with Bacillus Calmette-Guérin (BCG) on May 28, 2026. The decision represents an expansion of immunotherapy-based treatment strategies for a disease known for its high recurrence rate and long-term management needs.
NMIBC is the most common form of bladder cancer and is characterized by tumors confined to the bladder’s inner lining without invading the muscle layer. Although generally less aggressive than muscle-invasive disease, it frequently recurs after treatment and, in some cases, can progress, requiring ongoing surveillance and repeated intervention.
The approval is supported by data from the Phase 3 POTOMAC trial (NCT03528694), a randomized, multicenter study evaluating durvalumab plus BCG versus BCG alone in patients with high-risk NMIBC who had undergone transurethral resection of bladder tumor (TURBT).
The trial enrolled more than 1,000 patients and followed participants after TURBT, with the primary endpoint defined as investigator-assessed disease-free survival (DFS), measuring recurrence, progression to muscle-invasive or metastatic disease, or death.
Results showed that the durvalumab combination reduced the risk of disease recurrence, progression, or death by 32% compared with BCG alone (hazard ratio 0.68; 95% CI 0.50–0.93). Median disease-free survival was not reached in either group at the time of analysis.
Researchers also reported fewer DFS events in the combination arm, with 67 events compared with 98 events in the BCG-only group, suggesting improved disease control with the addition of durvalumab.
Durvalumab is an immune checkpoint inhibitor that blocks PD-L1, helping the immune system recognize and attack cancer cells more effectively. BCG, a long-established intravesical therapy for bladder cancer, stimulates a localized immune response within the bladder to target residual tumor cells.
The combination is designed to enhance both systemic and local immune activity, with the goal of improving durable tumor control and reducing recurrence risk in high-risk patients.
According to the FDA’s approval summary, the findings demonstrate a clinically meaningful improvement in disease-free survival, reinforcing the need for additional effective options beyond BCG alone in this patient population.
With the approval, durvalumab plus BCG becomes an available treatment option for eligible patients with high-risk NMIBC. However, clinicians emphasize that routine cystoscopic surveillance remains essential, as recurrence risk persists even after therapy.
Experts note that while the approval represents a significant advance in early-stage bladder cancer treatment, longer follow-up is still required to fully assess the durability of the benefit and its impact on overall survival outcomes.