Nivolumab and Ipilimumab (NIVO IPI) as first-line (1L) treatment for patients with metastatic renal-cell carcinoma (mRCC): A real-world benchmarking analysis from the International mRCC Database Consortium (IMDC).

4549 Background: NIVO IPI has demonstrated durable overall survival (OS) benefit with long-term follow-up in patients with mRCC. Real world outcomes and benchmarks for subgroups as well as conditional survival (CS) are required in the real world. Methods: Patients with mRCC treated with 1L NIVO IPI from the IMDC were analyzed, including various subgroups of interest. Outcomes reported will be objective response rates (ORR), median overall survival (mOS) and conditional survival (CS). CS is defined as survival among patients who were alive and on treatment after the requisite 3-month interval landmarks, as estimated using the Kaplan–Meier method. CS was calculated at landmarks while patients were still on treatment, and at landmarks regardless of treatment. Results: 2115 patients received 1L NIVO IPI; 148/1042/549 were categorized by IMDC risk group as favorable/intermediate/poor risk; 90% of patients had clear-cell histology, 32% had bone metastases, and 14% had sarcomatoid features. Median follow-up was 34 months (m); median duration of treatment was 4.8 m, and median time to next treatment was 11.2 m. 66% of patients received second-line treatment. ORR was 39.5% (8.3% CR) with primary progression seen in 28 mOS was longer in clear cell (47.8 m) than in non–clear cell (26.3 m) (p<0.001). mOS was significantly shorter in patients with sarcomatoid features (34.2 vs 47.0 m; p=0.02 mOS was also different by IMDC risk group: 53.3 m for favorable, 45.7 m for intermediate and 18.8 m for poor risk patients (p<0.001); and by response: 4-year was OS of 93.6% for patients with CR, 60.1% for PR, 43.6% for SD and 15.4% for patients with PD (p<0.001). CS during 1L NIVO IPI is detailed in Table 1 with greater survival with each successive landmark. Conclusions: We provide real-world benchmark survival results for patients with mRCC treated with 1L NIVO IPI, including subgroup analysis regarding the presence of sarcomatoid features, IMDC risk group, and ORR. Conditional survival provides a key understanding of a patient’s prognosis after having been on therapy or been alive for at certain time points. This is essential information for patient counselling and clinical trial design. Conditional survival (CS) through time landmarks, either on treatment or regardless of treatment. Landmark(mo) CS on NIVO IPI (N) CS on treatment If patient is still on therapy past landmarkmo (95% CI) CS (N) regardless of treatment continuation CS regardless of treatment continuationIf patient survived past landmarkmo (95% CI) 0 1965 41.4 (37.7–45.3) 2038 40.2 (36.7–44.5) 3 1129 54.5 (49.7–67.3) 1826 44.6 (40.7–49.4) 6 822 93.0 (60.9–NR) 1626 49.2 (44.6–53.5) 9 627 93.0 (84.2–NR) 1436 53.5 (49.2–59.2) 12 483 114 (84.2–NR) 1276 56.9 (51.1–66.8) 24 210 NR (NR–NR) 805 93.0 (72.8–NR) 36 101 NR (NR–NR) 519 NR (93.0–NR)