FRACTION-RCC: Innovative, high-throughput assessment of nivolumab + ipilimumab for treatment-refractory advanced renal cell carcinoma (aRCC).

Abstract

5007Background: The immuno-oncology (I-O) combination nivolumab + ipilimumab (NIVO+IPI) is approved for first-line (1L) and NIVO is approved for second-line treatment post TKI therapy in aRCC. The open-label, randomized, phase 2 Fast Real-Time Assessment of Combination Therapies in Immuno-Oncology (FRACTION-RCC; NCT02996110) platform study has an adaptive design allowing rapid evaluation of I-O therapies, including NIVO+IPI or other investigational combinations. This FRACTION analysis reports preliminary outcomes with NIVO+IPI in aRCC pts after progression on checkpoint inhibitor therapy. Methods: All pts, except 1, had previously received and progressed on checkpoint inhibitor treatment. Pts received NIVO+IPI (NIVO 3 mg/kg + IPI 1 mg/kg Q3W ×4, then after 6 weeks, NIVO 480 mg Q4W), up to 2 years or until progression, toxicity, or protocol-specified discontinuation. Primary endpoints were confirmed objective response rate (ORR; per investigator using RECIST v1.1), duration of response (DOR), and progression-free survival probability at week 24. Safety outcomes were reported. Results: 46 pts were randomized to NIVO+IPI. Pts had 0 (n = 1), 1 (n = 10), 2 (n = 12), 3 (n = 10), or ≥4 (n = 13) prior lines of therapy. All pretreated pts had prior anti-PD-(L)1-, none had prior anti-CTLA-4- therapy, and 37 had prior TKI-based therapy; 45 pts progressed on anti-PD-(L)1 as the most recent therapy. Most pts had clear cell aRCC (n = 44). After a median study follow-up of 8.9 months, ORR was 15.2%; no pts achieved complete response and 7 achieved partial response. DOR ranged from 2–19+ months (n = 7); 5 pts had ongoing response. Six of 7 responders had received ≥2 prior lines of therapy. Any-grade treatment-related adverse events (AEs) were reported in 36 pts (78.3%; fatigue, rash [both 19.6%], and diarrhea [17.4%] were most common). Grade 3–4 treatment-related AEs were reported in 13 pts (28.3%; diarrhea [8.7%], ↑amylase and ↑lipase [both 6.5%] were most common). Treatment-related immune-mediated AEs of any grade were reported in 22 pts (47.8%; rash [19.6%], diarrhea [17.4%], and ↑alanine aminotransferase [8.7%]). No treatment-related deaths were reported. Updated and expanded results with an additional 3 months of follow-up will be presented. Conclusions: These results suggest that NIVO+IPI may provide durable partial response in some pts with prior progression on checkpoint inhibitors, including some heavily pretreated pts. The safety profile of NIVO+IPI in FRACTION pts was similar to historic data in aRCC with this combination. Clinical trial information: NCT02996110 .