The Food and Drug Administration (FDA) has accepted for Priority Review the supplemental Biologics License Application (sBLA) for durvalumab, in combination with standard of care chemotherapy, for the treatment of patients with locally advanced or metastatic biliary tract cancer.

The sBLA submission was supported by data from the randomized, double-blind, placebo-controlled, phase 3 TOPAZ-1 trial ( Identifier: NCT03875235), which evaluated the efficacy and safety of durvalumab, a programmed death-ligand 1 (PD-L1) blocking antibody, plus chemotherapy in adults with first-line advanced biliary tract cancer.

Patients were randomly assigned to receive durvalumab or placebo via intravenous (IV) infusion every 3 weeks, in combination with chemotherapy (gemcitabine plus cisplatin) for up to 8 cycles, followed by monotherapy every 4 weeks until disease progression or other discontinuation criteria. The primary endpoint was overall survival (OS).

Based on results from an interim analysis, durvalumab plus chemotherapy reduced the risk of death by 20% compared with chemotherapy alone (hazard ratio [HR], 0.80; 95% CI, 0.66-0.97; 2-sided P =.021). The median OS was 12.8 months for durvalumab plus chemotherapy and 11.5 months for chemotherapy alone. An estimated 25% of durvalumab-treated patients were alive at 2 years compared with 10% of patients treated with chemotherapy alone. 

Durvalumab plus chemotherapy was also associated with a 25% reduction in the risk of disease progression or death (secondary endpoint) compared with chemotherapy alone (HR, 0.75; 95% CI, 0.64-0.89; 2-sided P =.001). Median progression-free survival was 7.2 months for durvalumab plus chemotherapy and 5.7 months for chemotherapy alone. The objective response rate was 26.7% and 18.7% for the combination and chemotherapy alone, respectively.

“People with advanced biliary tract cancer have faced poor outcomes and limited treatment options for too long, and today’s news for the TOPAZ-1 trial underscores the urgency to deliver new, effective therapies in this setting,” said Susan Galbraith, Executive Vice President, Oncology R&D, AstraZeneca. “We are working closely with the FDA to bring the first immunotherapy-based option to patients with this devastating cancer and potentially set a new standard of care with [durvalumab] plus chemotherapy.”

Durvalumab is currently marketed under the brand name Imfinzi and is approved for the treatment of unresectable, Stage III non-small cell lung cancer (NSCLC) and extensive-stage small cell lung cancer. The FDA is expected to make a decision on the application for the biliary tract cancer indication sometime in the third quarter of 2022.


  1. Imfinzi plus chemotherapy granted Priority Review in the US for patients with locally advanced or metastatic biliary tract cancer based on TOPAZ-1 phase III trial. News release. AstraZeneca. Accessed May 4, 2022.
  2. Imfinzi plus chemotherapy reduced risk of death by 20% in 1st-line advanced biliary tract cancer. News release. AstraZeneca. January 18, 2022. Accessed May 4, 2022.