The Efficacy and Safety of the Combination of Axitinib and Pembrolizumab‐activated Autologous DC‐CIK Cell Immunotherapy for Patients with Advanced Renal Cell Carcinoma: a Phase 2 Study

Abstract Objectives Although axitinib has achieved a preferable response rate for advanced renal cell carcinoma (RCC), patient survival remains unsatisfactory. In this study, we evaluated the efficacy and safety of a combination treatment of axitinib and a low dose of pembrolizumab‐activated autologous dendritic cells–co‐cultured cytokine‐induced killer cells in patients with advanced RCC. Methods All adult patients, including treatment‐naive or pretreated with VEGF‐targeted agents, were enrolled from May 2016 to March 2019. Patients received axitinib 5 mg twice daily and pembrolizumab‐activated dendritic cells–co‐cultured cytokine‐induced killer cells intravenously weekly for the first four cycles, every 2 weeks for the next four cycles, and every month thereafter. Results The 43 patients (22 untreated and 21 previously treated) showed a median progression‐free survival (mPFS) of 14.7 months (95% CI, 11.16–18.30). mPFS in treatment‐naive patients was 18.2 months, as compared with 14.4 months in pretreated patients (log‐rank P‐value = 0.07). Overall response rates were 25.6% (95% CI, 13.5–41.2%). Grade 3 or higher adverse events occurred in 5% of patients included hypertension (11.6%) and palmar‐plantar erythrodysesthesia (7.0%). Peripheral blood lymphocyte immunophenotype and serum cytokine profile analyses demonstrated increased antitumor immunity after combination treatment particularly in patients with a long‐term survival benefit, while those with a minimal survival benefit demonstrated an elevated proportion of peripheral CD8+TIM3+ T cells and lower serum‐level immunostimulatory cytokine profile. Conclusions The combination therapy was active and well tolerated for treatment of advanced RCC, either as first‐ or second‐line treatment following other targeted agents. Changes in immunophenotype and serum cytokine profile may be used as prognostic biomarkers.