Real World Efficacy of 1st-Line Nivolumab Plus Ipilimumab and its Practical Predictive Biomarkers in Advanced Renal Cell Carcinoma: First Analysis from RENOIR Study (KCSG GU22-13).

Purpose: We investigated the real-world efficacy of first-line nivolumab plus ipilimumab (NI) and its predictive clinicopathological biomarkers in patients with advanced renal cell carcinoma(aRCC).

Materials and methods: We retrospectively analyzed 466 patients with aRCC who started first-line NI between 2019 and 2023 at 21 Korean tertiary hospitals. The primary outcome was objective response rate (ORR). Secondary outcomes were duration of response (DoR), progression-free survival (PFS), overall survival (OS), and identification of practical clinicopathological biomarkers.

Results: Median age of patients was 65 years, and 77.7% were male. ORR was 44.8% including 5.2% of complete response, and median DoR was 39.8 months. Male sex and lung metastasis were predictive markers of objective response, and achieving complete response was significantly associated with a longer DoR (p=0.03). With a median follow-up duration of 23.7 months, the median PFS and OS were 11.5 and 44.2 months, respectively. Full exposure to four cycles of ipilimumab was significantly associated with better PFS and OS. Durable response could significantly predict better OS, whereas multiple metastatic sites (≥4) and poor IMDC risk were two independent predictors for inferior OS. Among the 50 patients who completed 2 years of NI treatment, continuation of nivolumab beyond 2 years has marginally improved OS (p=0.09).

Conclusion: First-line NI showed comparable and competent efficacy in Korean patients with aRCC. We suggest completing full exposure to ipilimumab and durable response as practical predictors of enriched benefits of NI in our real-world.