Pembrolizumab With or Without Lenvatinib as First-Line Therapy for Recurrent or Metastatic Head and Neck Squamous Cell Carcinoma: Phase III LEAP-010 Study

PURPOSE – The PD-1 inhibitor pembrolizumab is approved as first-line treatment for recurrent/metastatic head and neck squamous cell carcinoma (R/M HNSCC). In LEAP-010 (ClinicalTrials.gov identifier: NCT04199104), the multikinase inhibitor lenvatinib plus pembrolizumab was evaluated as first-line therapy in participants with PD-L1 combined positive score (CPS) ≥1 R/M HNSCC.METHODS – In this phase III, randomized, placebo-controlled, double-blind study, participants 18 years and older with PD-L1 CPS ≥1 R/M HNSCC deemed incurable by local therapy were randomly assigned 1:1 to lenvatinib 20 mg plus pembrolizumab 200 mg IV once every 3 weeks for ≤35 cycles or placebo orally once daily plus pembrolizumab 200 mg IV once every 3 weeks for ≤35 cycles. Primary end points were objective response rate (ORR), progression-free survival (PFS), and overall survival (OS). Per the prespecified analysis plan, ORR and PFS were reported from the first interim analysis (IA1; data cutoff: July 6, 2022), and OS from IA2 (data cutoff: May 30, 2023).RESULTS – Five hundred eleven participants were randomly assigned to lenvatinib plus pembrolizumab (n = 256) or placebo plus pembrolizumab (n = 255). The median time from random assignment to data cutoff was 11.5 months for IA1 and 21.3 months for IA2. At IA1, the median PFS was 6.2 months for lenvatinib plus pembrolizumab versus 2.8 months for placebo plus pembrolizumab (hazard ratio [HR], 0.64 [95% CI, 0.50 to 0.81]; P =.0001040); the ORR was 46.1% versus 25.4%, respectively (difference = 20.2% [95% CI, 10.5 to 29.6]; P =.0000251). At IA2, the median OS was 15.0 months for lenvatinib plus pembrolizumab versus 17.9 months for placebo plus pembrolizumab (HR, 1.15 [95% CI, 0.91 to 1.45]; P =.882). At IA2, 170 (66.9%) participants receiving lenvatinib plus pembrolizumab had grade 3-4 all-cause adverse events compared with 97 (38.3%) participants on placebo plus pembrolizumab.CONCLUSION – In participants with PD-L1 CPS ≥1 R/M HNSCC, first-line lenvatinib plus pembrolizumab significantly improved ORR and PFS, but not OS, compared with placebo plus pembrolizumab. The safety profile was consistent with published data.