On May 28, 2026, the U.S. Food and Drug Administration approved durvalumab in combination with Bacillus Calmette-Guerin for adult patients with BCG-naïve, high-risk non–muscle-invasive bladder cancer (NMIBC). Durvalumab is marketed as Imfinzi by AstraZeneca. According to the FDA-recommended dosage, durvalumab is given with BCG induction and maintenance treatment.
Background
Non–muscle-invasive bladder cancer refers to bladder cancer that has not invaded the muscle layer of the bladder wall. In this FDA approval, high-risk disease was defined as the presence of a T1 tumor, Grade 3 or high-grade tumor, carcinoma in situ, or multiple, recurrent, and large tumors. The approval applies to patients who are BCG-naïve, meaning they have not previously received Bacillus Calmette-Guerin treatment for high-risk non–muscle-invasive bladder cancer.
How Does Durvalumab Work?
Durvalumab is an immune checkpoint inhibitor that targets programmed death-ligand 1, also known as PD-L1. PD-L1 can be expressed on tumor cells and tumor-associated immune cells, and it can reduce T-cell activity through interactions with PD-1 and CD80.
By binding to PD-L1, durvalumab blocks these interactions and helps release inhibition of the immune response. This can support T-cell activation and anti-tumor immune activity. Durvalumab does not work like chemotherapy. Instead of directly killing cancer cells, it helps the immune system maintain an anti-tumor response.
Read more about Durvalumab (Imfinzi) on OncoDaily.
POTOMAC Trial and Study Design
The efficacy and safety of durvalumab plus BCG were evaluated in POTOMAC (NCT03528694), a randomized, open-label, multicenter phase 3 trial. The study enrolled 1,018 patients with high-risk non–muscle-invasive bladder cancer after transurethral resection of bladder tumor.
Patients were randomized in a 1:1:1 ratio to receive durvalumab every 4 weeks for 13 cycles plus BCG induction and maintenance, durvalumab every 4 weeks for 13 cycles plus BCG induction only, or BCG induction and maintenance alone.
The major efficacy outcome measure was investigator-assessed disease-free survival. Disease-free survival was defined as the time from randomization to the first recurrence of high-risk non–muscle-invasive bladder cancer, persistent carcinoma in situ, muscle-invasive bladder cancer, metastatic disease, or death.
Efficacy Outcomes
Durvalumab plus BCG induction and maintenance showed a statistically significant improvement in disease-free survival compared with BCG induction and maintenance alone. The disease-free survival hazard ratio was 0.68, with a 95% confidence interval of 0.50 to 0.93 and a two-sided p-value of 0.0154. Median disease-free survival was not reached in either arm.
Updated POTOMAC Results at ASCO 2026
At the 2026 ASCO Annual Meeting, Maria De Santis, MD, from Charité Universitaetsmedizin Berlin and the Medical University of Vienna, presented updated findings from the phase 3 POTOMAC trial, including the planned 5-year overall survival analysis and patient-reported outcomes.
At the October 3, 2025 data cutoff, median follow-up was 72 months. For durvalumab plus BCG induction and maintenance versus BCG induction and maintenance alone, the overall survival hazard ratio was 0.81, with a 95% confidence interval of 0.54 to 1.19.
The 5-year overall survival rate was 88% with durvalumab plus BCG induction and maintenance and 86% with BCG induction and maintenance alone. Median overall survival was not reached in either arm.
Read more about POTOMAC Results at ASCO 2026 on OncoDaily.
Patient-Reported Outcomes
Patient-reported outcomes were analyzed at the April 3, 2025 data cutoff. Baseline questionnaire completion was high, with completion rates of 74% versus 79% for EORTC QLQ-C30 and 80% versus 82% for EORTC QLQ-NMIBC24. Baseline patient-reported outcome scores were generally similar between treatment groups.
Across EORTC QLQ-C30 measures, adjusted mean changes from baseline showed modest deterioration in global health status/quality of life and physical functioning, along with increased fatigue, in both treatment arms. Overall, changes were generally similar between groups. The between-arm differences were −2.7 for global health status/quality of life, −2.6 for physical functioning, and 4.0 for fatigue.
For EORTC QLQ-NMIBC24, adjusted mean change-from-baseline scores were not clinically meaningful and were similar between treatment arms across urinary symptoms, intravesical treatment issues, future perspective or worries, and sexual functioning.
Across abdominal pain, diarrhea, and painful urination, PRO-CTCAE worsening rates through Week 106 were similar between arms. Urinary frequency worsening was numerically higher with durvalumab plus BCG than with BCG alone, but the difference was 10% or less.
Safety Profile
The prescribing information for durvalumab includes warnings and precautions for immune-mediated adverse reactions, infusion-related reactions, complications of allogeneic hematopoietic stem cell transplantation, and embryo-fetal toxicity. Healthcare professionals should report serious adverse events suspected to be associated with the use of any medicine or device to the FDA MedWatch Reporting System.
Dosing and Administration
For patients weighing at least 30 kg, the recommended durvalumab dose is 1,500 mg every 4 weeks for 13 cycles in combination with BCG induction and maintenance treatment. Treatment should continue until recurrence of high-risk disease, disease progression, unacceptable toxicity, or a maximum of 13 cycles.
Takeaway
The FDA approved durvalumab plus BCG for adult patients with BCG-naïve, high-risk non–muscle-invasive bladder cancer. In POTOMAC, durvalumab plus BCG induction and maintenance significantly improved disease-free survival compared with BCG induction and maintenance alone. Updated results presented at ASCO 2026 showed that median overall survival was not reached in either arm after a median follow-up of 72 months, with 5-year overall survival rates of 88% and 86%, respectively. Patient-reported outcomes were generally similar between treatment groups.
The full information about the approval is available on the official FDA website.
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