Aims: First-line N+C significantly improved progression-free survival (PFS), overall survival (OS), and objective response rate (ORR) vs sunitinib in aRCC patients in the phase 3 CheckMate 9ER trial (NCT03141177; Choueiri NEJM 2021). Assessing outcomes of N+C vs sunitinib by baseline disease characteristics can inform clinical decision making.
Methods: Patients with clear cell aRCC were randomized to nivolumab 240 mg IV Q2W + cabozantinib 40 mg PO QD vs sunitinib 50 mg PO QD (4 weeks on/2 weeks off). In this post hoc exploratory analysis, PFS, OS, and ORR were assessed across patient subgroups: IMDC risk, number of organs with ≥1 target/nontarget lesion (T/NT), sum of diameters of target lesions (sDTL), and site of metastasis. PFS and ORR were evaluated per RECIST v1.1 by blinded independent central review.
Results: Median follow-up in ITT patients was 23.5 months. N+C was favored over sunitinib for PFS across all subgroups, median (hazard ratio [HR], 95% CI): IMDC risk favorable, 25 vs 13 months (0.58, 0.36-0.93); intermediate, 17 vs 9 months (0.58, 0.45-0.76); poor, 10 vs 4 months (0.36, 0.23-0.56); T/NT 1 organ site, 25 vs 13 months (0.53, 0.32-0.88); ≥2 organ sites, 15 vs 7 months (0.53, 0.43-0.67); sDTL <72.1mm, 20 vs 10 months (0.52, 0.39-0.71); ≥72.1mm, 11 vs 6 months (0.53, 0.40-0.70); metastases lung, 17 vs 8 months (0.51, 0.40-0.64); bone, 18 vs 4 months (0.38, 0.25-0.59); liver, 11 vs 6 months (0.51, 0.33-0.79). N+C was favored over sunitinib for ORR across all subgroups (range, 38%-66% vs 10%-44%) and for OS across most subgroups (HR range, 0.45-0.94). Complete responses were seen with N+C in all subgroups (range, 1%-20%).
Conclusions: Efficacy benefits with N+C vs sunitinib were maintained regardless of IMDC risk, metastasis site, or extent of tumor burden at baseline, supporting N+C as first-line treatment for patients with aRCC.