A randomized phase 2 study of durvalumab monotherapy and in combination with tremelimumab in patients with metastatic pancreatic ductal adenocarcinoma (mPDAC): ALPS study.

217Background: Durvalumab (D) and tremelimumab (T), monoclonal antibodies against PD-L1 and CTLA-4 immune checkpoints, have shown efficacy as monotherapy/combination therapy in multiple cancer types. Herein, we report a randomized phase 2 study to evaluate efficacy and safety of D monotherapy with or without T (D+T) in previously treated mPDAC. Methods: Part A was a lead-in safety and signal-seeking study with plans to expand to Part B as a nonrandomized or randomized controlled study pending efficacy signal. Eligible pts had progressive disease (PD) following front-line 5-FU- or gemcitabine-based therapy. In Part A, pts were randomized to D (1.5 g IV Q4W) or D+T (D 1.5 g IV + T 75 mg IV Q4W × 4 doses → D 1.5 g IV Q4W) for up to 12 months (mo) or until confirmed PD or unacceptable toxicity. Primary endpoint was investigator-assessed objective response rate per RECIST 1.1. Results: In Part A, 65 pts were randomized to D (n = 33) or D+T (n = 32). Due to a pretreatment death, 64 pts received therapy. Eleven ...