Durvalumab Granted Accelerated Approval in Urothelial Carcinoma
On May 1, 2017, durvalumab (Imfinzi) was granted accelerated approval by the U.S. Food and Drug Administration (FDA) for the treatment of patients with locally advanced or metastatic urothelial carcinoma whose disease progressed during or after platinum-based chemotherapy or within 12 months of neoadjuvant or adjuvant treatment with platinum-based chemotherapy. For the assessment of the programmed cell death ligand 1 (PD-L1) protein in formalin-fixed, paraffin-embedded urothelial carcinoma tissue, the FDA also approved the Ventana PD-L1 (SP263) Assay as a complementary diagnostic.
The study on which this approval was based is a single-arm trial of 182 patients with locally advanced or metastatic urothelial carcinoma whose disease progressed after prior platinum-based chemotherapy. The dosage schedule for durvalumab was 10 mg/kg given intravenously every 2 weeks.
The confirmed objective response rate was 17.0%, and at the data cutoff for analysis, the median response duration was not reached (range, 0.9+ to 19.9+ months). In 95 patients with a high PD-L1 score, the confirmed objective response rate was 26.3%; in 73 patients with a low or negative PD-L1 score, the confirmed objective response rate was 4.3%.
The most common adverse reactions in at least 15% of patients were fatigue, musculoskeletal pain, constipation, decreased appetite, nausea, peripheral edema, and urinary tract infection. Grade 3/4 adverse events were seen in 43% of patients.