Everolimus (E) plus bevacizumab (B) is effective first-line treatment for patients (pts) with advanced renal cell carcinoma (RCC) with papillary features (PF): Results from a phase II trial.

Abstract

627 Background: We previously reported on a phase II trial of E+B across various non-clear cell RCC histologies and observed significant activity among pts with papillary or unclassified RCC ( uRCC ) with PF (objective response rate [ORR] 39%, median progression-free survival [PFS] 12.9 months [m]; Voss, JCO, 2016). An expansion cohort limited to these two histologies was conducted to confirm the efficacy of E+B. Methods: E + B was administered at standard doses until progressive disease (PD) or intolerance to therapy. The current analysis included 19 pts with pRCC or uRCC with PF in the initial cohort and 20 pts in the expansion cohort (total n=39). The primary endpoint was 6 month PFS with secondary endpoints of ORR, median PFS, and overall survival (OS). Correlative analyses included next generation sequencing (NGS) from tumor and germline across >341 genes of interest. Results: Of 39 pts, 24 had uRCC with PF, 14 had papillary RCC, and 1 had translocation RCC with PF. Among 37 evaluable pts, the ORR was 35%; 43% for uRCC with PF and 23% for papillary RCC. Six-month PFS for all 39 pts was 78%; 82% for uRCC with PF and 68% for papillary RCC. Median PFS was 13.7m; 13.7m for uRCC with PF and 8.4m for papillary RCC (Table). With median followup of 17.6m, median OS is 33.9m. Toxicity with E+B was similar to previous reports. 33 of 39 pts had NGS performed and partial responses were observed across a wide spectrum of genomic alterations, including several recurrently seen in papillary RCC variants such as mutations in FH, MET, NF2, and ARID1a. Conclusions: The expansion cohort confirms the activity of E+B for pts with advanced papillary RCC or uRCC with PF with superior ORR, PFS, and OS compared to historical results with sunitinib for these histologies. E+B represents a new standard first-line treatment option for these pts. Clinical trial information: NCT01399918. [Table: see text]