In ccRCC, first-line pembro + lenva improved OS, PFS, and ORR vs sunitinib in the phase 3 KEYNOTE-581 study. In nccRCC, first-line pembro monotherapy showed promising antitumor activity in cohort B of the phase 2 KEYNOTE-427 study. We report the first results of KEYNOTE-B61, a single-arm, phase 2 study (NCT04704219) evaluating pembro + lenva as first-line treatment for nccRCC.
Adults with previously untreated advanced nccRCC and measurable disease per RECIST v1.1 received pembro 400 mg IV Q6W up to 18 cycles (∼2 y) + lenva 20 mg orally QD. Primary end point was confirmed ORR (CR + PR) per RECIST v1.1 by BICR; secondary end points were DOR, DCR (CR + PR + SD), PFS, OS, and safety. Efficacy was evaluated in treated pts who had the opportunity for ≥24 wk of follow-up. Safety was evaluated in all treated pts.
Of 147 treated pts, 87 (59.2%), 26 (17.7%), and 19 (12.9%) had papillary, chromophobe, and unclassified histology, respectively; 15 pts had translocation (4.1%), medullary (0.7%), or other (5.4%) histology. As of January 31, 2022, median follow-up for pts who had the opportunity for ≥24 wk of follow-up (n=82) was 8.2 mo (range, 5.5-10.5). Of these 82 pts, confirmed ORR was 47.6% (95% CI, 36.4-58.9; 3 CRs [3.7%]; 36 PRs [43.9%]). DCR was 79.3% (95% CI, 68.9-87.4). Median DOR was not reached (range, 1.4+ to 7.2+ mo). ORR and DCR in histologic subgroups are shown in the table. The 6-month PFS rate was 72.3% (95% CI, 60.7-81.0) and the 6-month OS rate was 87.8% (95% CI, 78.5-93.2). In all treated pts (N=147), any grade treatment-related AEs (TRAEs) occurred in 127 pts (86.4%), most commonly hypertension (n=71; 48.3%), diarrhea (n=37; 25.2%), and hypothyroidism (n=37; 25.2%). Grade 3-4 TRAEs occurred in 51 pts (34.7%). No deaths occurred due to TRAEs. Table: 1448O
In this preliminary analysis, pembro + lenva showed promising antitumor activity and manageable safety in pts with advanced nccRCC. No new safety signals emerged with this combination.
Clinical trial identification
NCT04704219, Release date: January 11, 2021.