Analysis of the benefit of salvage chemotherapy after progression on nivolumab in patients with squamous cell carcinoma of the head and neck.

BACKGROUND: Checkpoint inhibitor (CI) therapies have shown benefit in the treatment of locally recurrent or metastatic head and neck squamous cell carcinoma (R L/M HNSCC). Previous studies have suggested a superior benefit of salvage chemotherapy (SCT) in R/M HNSCC after progression on CI. We aimed to describe the benefit of SCT after progression on nivolumab. PATIENTS AND METHODS: Patients were eligible if they received at least one injection of SCT in the treatment of R/M HNSCC after progression on nivolumab between 2017 and 2022. The present work was a retrospective and monocenter study. Primary endpoint was the objective response rate (ORR) on first regimen of salvage chemotherapy (SCT1). Secondary endpoints were disease-control rate (DCR), ORR on second course of SCT (ORR2), progression-free survival (PFS) on SCT1 and SCT2 (PFS2) and overall survival (OS). RESULTS: Eighty-three patients received an SCT. The ORR on STC1 was 32%. Median progression-free survival (PFS) was 2.20 months (CI 95% 2.06-3.71). Median OS was 5.55 months (CI 95% 4.82-10.20). The ORR to the first line of treatment in the relapse setting was an independent prognostic factor for SCT1 PFS and OS. CONCLUSION: In R/M HNSCC, SCT following nivolumab is associated with ORRs of 32%. These results are consistent with other publications that suggest a superior benefit of SCT after CI treatment, independent of the tumor outcome on previous immunotherapy.