FDA Approves Durvalumab and BCG for High-Risk NMIBC

In a significant development for the urologic oncology community, the U.S. Food and Drug Administration (FDA) has approved durvalumab (Imfinzi) in combination with Bacillus Calmette-Guerin (BCG) for the treatment of adult patients with BCG-naïve, high-risk non-muscle invasive bladder cancer (NMIBC).

The approval provides a new therapeutic avenue for patients whose disease has not yet been treated with BCG and carries a high risk of progression.

The POTOMAC trial: Efficacy and study design

The regulatory decision was supported by results from the POTOMAC study (NCT03528694), a randomized, open-label, multicenter clinical trial. The study enrolled 1,018 patients with high-risk NMIBC following a transurethral resection of the bladder tumor (TURBT). To qualify as "high-risk," patients had to present with at least one of the following clinical features: a T1 tumor, grade 3/high-grade tumor, carcinoma in situ (CIS), or multiple, recurrent, and large tumors.

Participants were randomized 1:1:1 into three arms: durvalumab plus BCG induction and maintenance, BCG induction and maintenance alone, or an additional investigational combination. The primary efficacy endpoint was investigator-assessed disease-free survival (DFS), which the study defined as the interval between randomization and the first instance of NMIBC recurrence, persistent CIS, progression to muscle-invasive disease, metastasis, or death.

Data from the trial demonstrated a statistically significant improvement in DFS for patients receiving the durvalumab and BCG combination compared to those receiving BCG alone. The hazard ratio was 0.68 (95% CI: 0.50, 0.93; p=0.0154), representing a 32% reduction in the risk of recurrence or death. Notably, the median DFS was not reached in either treatment arm at the time of the analysis.

Dosing and nursing considerations

For oncology nurses administering this new regimen, the recommended dosage of durvalumab for patients weighing 30 kg or more is 1,500 mg administered every four weeks. This is given in combination with the standard BCG induction and maintenance schedule. The treatment protocol for durvalumab is designed to continue for a maximum of 13 cycles or until the patient experiences disease recurrence, progression, or unacceptable toxicity.

Because durvalumab is an immune checkpoint inhibitor, nursing staff must remain vigilant for immune-mediated adverse reactions, which can affect any organ system. The FDA prescribing information also includes specific warnings regarding infusion-related reactions, complications associated with allogeneic hematopoietic stem cell transplantation, and embryo-fetal toxicities.

Clinical significance

This approval marks a shift in the early-stage bladder cancer landscape by integrating immunotherapy into the frontline setting alongside BCG. By improving DFS in the BCG-naïve population, this combination may help delay the progression to more invasive disease states that require radical cystectomy.

The FDA’s review of this application was conducted under a standard review timeline and utilized the Assessment Aid, a voluntary submission from AstraZeneca intended to streamline the agency’s evaluation process. Healthcare providers are encouraged to report any suspected serious adverse events to the FDA’s MedWatch Reporting System.

Reference

1. FDA approves durvalumab in combination with Bacillus Calmette-Guerin for high-risk non-muscle invasive bladder cancer. U.S. Food and Drug Administration. Published May 28, 2026. Accessed May 28, 2026. https://www.fda.gov/drugs/resources-information-approved-drugs/fda-approves-durvalumab-combination-bacillus-calmette-guerin-high-risk-non-muscle-invasive-bladder