PDIGREE: An adaptive phase III trial of PD-inhibitor nivolumab and ipilimumab (IPI-NIVO) with VEGF TKI cabozantinib (CABO) in metastatic untreated renal cell cancer (Alliance A031704).

TPS366 Background: First-line treatment of mRCC has rapidly changed to include IPI-NIVO or CABO, with clinical benefit of each based on the Checkmate 214 and CABOSUN (A031203) trials. Combination immunotherapy with VEGF therapies has shown benefit over sunitinib in the JAVELIN 101 and KEYNOTE 426 trials. It is yet unclear which patients (pts) benefit most from combination immunotherapy-VEGF inhibitors, and the optimal sequence of drugs. Methods: In an adaptive, randomized, multicenter phase III trial (Alliance A031704, PDIGREE), pts start treatment with induction IPI 1 mg/kg and NIVO 3 mg/kg intravenously (IV) once every 3 weeks. Key inclusion criteria include clear cell mRCC, International Metastatic RCC Database Consortium (IMDC) intermediate or poor risk, Karnofsky performance status >70, and no prior treatments for mRCC. Based on 3-month radiographic assessment (after completing IPI-NIVO combination), pts with complete responses (CR) undergo maintenance NIVO 480 mg IV every 4 weeks; pts with progression of disease (PD) switch to CABO 60 mg oral daily; pts with non-CR/non-PD are randomized to NIVO 480 mg IV every 4 weeks versus NIVO 480 mg IV every 4 weeks with CABO 40 mg oral daily. Randomization is stratified by IMDC risk criteria and presence of bone metastases. The primary endpoint of the study is overall survival (OS). We hypothesize that 3-year OS will improve to 70% for NIVO-CABO compared to 60% for NIVO alone; to achieve 85% power with a two-sided alpha of 0.05 and exponential distribution, 696 patients will be randomized. Accounting for 30% patients with either CR or PD, and 5% dropout from toxicity, up to 1046 pts will be enrolled. Key secondary endpoints include progression-free survival, 12-month CR rate, overall response rate based on RECIST 1.1 and iRECIST criteria, and toxicity profiles. Quality of life will be assessed based on the FKSI-19, PROMIS-fatigue, and EQ5D-5L questionnaires. Biomarkers associated with CR, tissue-based and plasma-based biomarkers will be assessed. Updated enrollment through January 2021 will be presented. Clinical trial information: NCT03793166 .