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.
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).
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. 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). 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). 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.
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.
Xevinapant (an inhibitor of apoptosis proteins inhibitor) added to chemoradiotherapy did not improve event-free survival (EFS) or overall survival (OS); in fact, OS was worse in the combination arm.
The KEYNOTE-689 trial evaluated perioperative pembrolizumab + SOC (surgery + adjuvant RT ± cisplatin) in resectable, locally advanced head and neck squamous-cell carcinoma (HNSCC) that is at least 1% PDL1 positive. The addition of pembrolizumab significantly improved 3-year event-free survival (EFS) in all PD-L1 subgroups: CPS≥10 (59.8% vs 45.9%), CPS≥1 (58.2% vs 44.9%), and the total population (57.6% vs 46.4%). Three-year overall survival (OS) also favored pembrolizumab: CPS≥10 (68.2% vs 59.2%), CPS≥1 (69.0% vs 60.2%), and total (68.4% vs 61.1%), though OS was not formally tested at this interim. Toxicities were as expected. Bottom line: perioperative pembro is now a part of the treatment paradigm for locally advanced HNCSCC with PDL1 expression.
Based on these findings, Carbo/Taxol+Pembro is an active regimen in met-HNC and an option for those patients who are not good candidates for 5FU based therapy.
Although immunotherapy did not beat chemotherapy but was non inferior and with more favorable safety.
Pembro with chemotherapy or alone better then cetuximab combination, also improved responses to subsequent therapy.