Safety outcomes of pembrolizumab with platinum agent chemotherapy combined with 5-fluorouracil or taxane derivative in head and neck cancer

Abstract

Introduction For patients with metastatic head and neck squamous cell cancer (HNSCC), the outcomes of pembrolizumab in combination with a platinum agent and taxane as first-line therapy remain unknown. The purpose of this study is to characterize the impact of substituting the 5-fluorouracil (5-FU) backbone for a taxane in this chemoimmunotherapy regimen on safety/tolerability and survival outcomes. Methods This was an IRB-approved, single-center, retrospective, active comparator, new-user design study in adult patients with HNSCC treated between January 2018 and September 2021. The primary objective was to assess safety and tolerability of pembrolizumab in combination with a platinum agent and taxane against an active comparator arm of pembrolizumab in combination with a platinum agent and 5-FU. Safety and tolerability were evaluated by assessing differences in overall toxicities, with further secondary analysis evaluating differences in hematologic toxicities and pre-defined non-hematologic toxicities. Results There was no statistical difference demonstrated with the primary endpoint between the cohorts. Reduced toxicity rates were found in the taxane arm for mucositis and creatinine levels. No grade 4 non-hematologic toxicities were reported. Patients receiving 5-FU were more likely to have dose reductions upfront, discontinue treatment due to intolerances and had significantly higher mucositis. Conclusions This study helps to characterize the safety profile and activity of pembrolizumab in combination with a platinum agent and taxane derivative in HNSCC patients. Within our study, substitution of 5-FU with a taxane did not show an increased risk of toxicities, worsened survival, or decreased odds of achieving a response. Mucositis and elevated creatinine rates were significantly reduced within the taxane arm.