36 Real-world treatment patterns and clinical outcomes of metastatic renal cell carcinoma patients post immune-oncology (IO) and Vascular Endothelial Growth Factor (VEGF) receptor targeted therapies

Abstract Background The metastatic renal cell carcinoma (mRCC) treatment landscape has rapidly evolved with approval of newer IO agents and VEGF targeted tyrosine kinase inhibitors (TKIs). However, real-world treatment patterns and clinical outcomes data for mRCC in post IO and TKI setting is limited. The objective of this study is to describe real-world treatment patterns and clinical outcomes of mRCC patients with a prior receipt of IO and TKI therapies in community oncology settings. Methods This retrospective cohort study utilized data from The US Oncology Network (iKnowMed) electronic health record database. The study cohort included adult mRCC patients receiving subsequent line of therapy (LOT; index date) post IO and TKI in combination or sequence between January-18’ and March-23’. All patients were followed from the index date until June-23’ to examine treatment pattern and estimate overall survival (OS), real-world time on treatment (rwToT), and real-world time to next treatment (rwTTNT) by line of therapy (LOT) and individual index regimen (with sample size ≥10). LOT was assigned based on patient’s absolute order of treatment regimen using start and stop dates. OS was defined as the time between Index date and the date of death due to any cause. Descriptive analyses were used to describe patient characteristics and treatment pattern. Time-to-event outcomes (OS, rwToT, and rwTTNT) from index date were summarized using Kaplan-Meier method with a log-rank test by individual regimens. A multivariate analysis using Cox proportional hazards model was performed to assess the association of index regimens with clinical outcomes after controlling for patient characteristics. Results The study cohort included 820 patients. The median age was 66 (range: 58, 72) years, 72.6% were male and 77.1% were Caucasian. Moreover, 60.0% had an Eastern Co-operative Oncology Group (ECOG) performance status of 0-1 and 74.5% had intermediate/poor IMDC risk score. Overall, 253 (30.9%) received index treatment in LOT2, 509 (62.1%) in LOT3 and 58 (7.1%) in LOT4+. The most common treatments post IO and TKI settings were cabozantinib (35.6%), everolimus plus lenvatinib (9.5%), ipilimumab plus nivolumab (7.4%), and axitinib (7.2%). The median OS for LOT2, LOT3, and LOT4 was (18.0, 17.8, and 28.6 months, respectively). The median rwTOT for LOT2 was 2.5 months, LOT3 was 3.5 months, and LOT4 was 6.2 months. The median rwTTNT for LOT2, LOT3, and LOT4 was 6.4, 7.7, and 11.5 months, respectively. Statistically significant difference across individual regimens was observed for OS, rwToT, and rwTTNT (Table). Conclusions This study presents one of the most comprehensive analysis of treatment patterns and clinical outcomes among mRCC patients in the post IO and TKI settings. TKI-with or without IO-based treatments were the most preferred treatments and associated with improved survival. Overall, clinical outcomes in the post IO and VEGF/TKI setting are limited, and novel treatments are needed in this patient population.