AstraZeneca announced Friday that its marketing application for the investigational PD-L1 antibody durvalumab was granted priority review by the FDA as a potential treatment for patients with locally advanced or metastatic urothelial carcinoma whose disease progressed during or after at least one standard platinum-containing regimen. Chief medical officer Sean Bohen stated the "acceptance of [our submission for] durvalumab in urothelial cancer is an important milestone for patients who still face considerable unmet medical need in this area."
AstraZeneca noted that its filing was supported by data from the urothelial carcinoma cohort of Study 1108, an ongoing Phase I/II trial testing durvalumab, also known as MEDI4736, in patients with advanced solid tumours. Meanwhile, preliminary results from a Phase I/II study unveiled  at the ASCO conference in June showed that durvalumab monotherapy was associated with an objective response rate of 31 percent in all-evaluable patients with advanced urothelial bladder cancer, and a rate of 46 percent in those with PD-L1-high-expressing tumours.
The FDA, which awarded durvalumab breakthrough therapy status  earlier this year, is expected to make a final decision on whether to approve the drug in the urothelial carcinoma indication in the second quarter of 2017.
AstraZeneca noted that durvalumab is also being investigated as monotherapy and in combination with the CTLA-4 monoclonal antibody tremelimumab in the Phase III DANUBE study as a possible first-line treatment for patients with metastatic urothelial carcinoma. The combination is also being assessed in late-stage trials for non-small-cell lung cancer (NSCLC) and for head and neck squamous cell carcinoma (HNSCC). The FDA recently lifted a partial clinical hold on trials testing durvalumab in patients with HNSCC following reports of bleeding incidents.
Meanwhile, in October 2015, AstraZeneca temporarily halted  two NSCLC trials evaluating the combination of durvalumab plus Tagrisso (osimertinib), formerly known as AZD9291, due to an increase in the incidence of interstitial lung disease-like reports. The company later disclosed  that Phase II data from another study would likely be insufficient to support regulatory submissions of durvalumab monotherapy for NSCLC, with Bohen saying at the time that "we will make that determination following a full analysis of the data."