Abstract
4502 Background: In the phase 3 CLEAR trial, L+P showed clinically meaningful and statistically significant benefits in PFS (primary endpoint) and OS, and improved ORR compared with S in 1L aRCC (Motzer NEJM 2021). Here, we report 4-yr follow-up results from the final prespecified OS analysis of CLEAR (data cutoff: 31 Jul 2022). Methods: Treatment-naïve pts (n=1069) who had aRCC with a clear-cell component were randomized (1:1:1) to receive: L 20 mg PO QD + P 200 mg IV Q3W; or L 18 mg + everolimus 5 mg PO QD; or S 50 mg PO QD (4 wks on/2 wks off). Stratification factors were geographic region and MSKCC prognostic risk group. This final prespecified OS analysis was triggered by ~304 death events in 2 arms. OS, PFS, ORR, duration of response (DOR), and PFS on next-line therapy (PFS2) were assessed for L+P and S. PFS, ORR and DOR were assessed per independent review using RECIST v1.1. Nominal P-values are shown. Results: At a median follow-up (IQR) of 49.8 mos (41.4–53.1) for L+P and 49.4 mos (41.6–52.8) for S, 149 and 159 deaths had occurred, respectively. OS benefit with L+P vs S was maintained (HR, 95% CI; 0.79, 0.63–0.99). OS favored L+P vs S across MSKCC risk groups (HR, 95% CI; favorable [fav]: 0.89, 0.53–1.50; intermediate [int]: 0.81, 0.62–1.06; poor: 0.59, 0.31–1.12). PFS benefit of L+P vs S was maintained (HR, 95% CI; 0.47, 0.38–0.57). PFS favored L+P vs S across MSKCC risk groups (HR, 95% CI; fav: 0.46, 0.32–0.67; int: 0.51, 0.40–0.65; poor: 0.18, 0.08–0.42). ORR was greater with L+P (71.3%; complete response [CR], 18.3%) vs S (36.7%; CR, 4.8%) (relative risk, 95% CI; 1.94, 1.67–2.26). Less pts in the L+P arm (181/355, 51.0%) received subsequent anticancer therapies compared with the S arm (246/357, 68.9%); 56 (15.8%) and 195 (54.6%) received PD-1/PD-L1 checkpoint inhibitors, respectively. Analysis of OS adjusted for subsequent therapies will be presented. PFS2 was longer with L+P vs S (43.3 vs 25.9 mos; HR, 95% CI; 0.63, 0.51–0.77). Grade ≥3 treatment-related adverse events occurred in 74.1% and 60.3% pts in the L+P and S arms, respectively. Conclusions: L+P continues to demonstrate clinically meaningful benefit vs S in OS, PFS, ORR, and CR in the 1L treatment of pts with aRCC at 4-yr follow-up, thus supporting the robustness of the primary analysis data from CLEAR. Clinical trial information: NCT02811861 .[Table: see text]