Efficacy and optimal combination timing of chemotherapy combined with PD-1 inhibitor in advanced cervical cancer: a multicenter retrospective cohort study.

Background: This study aimed to investigate the efficacy and safety of chemotherapy combined with programmed cell death protein 1 (PD-1) inhibitors in the treatment of advanced cervical cancer and the effect of optimal combination timing on prognosis. Methods: From March 2020 to December 2021, the clinical data of 116 patients with advanced cervical cancer who received PD-1 inhibitors combined with chemotherapy were collected. The clinical characteristics and adverse events of the patients were recorded until the cut-off date of follow-up. The primary endpoints were progression-free survival (PFS), the objective response rate (ORR), and safety; the secondary endpoints were the disease-control rate (DCR) and overall survival (OS). Multivariate Cox proportional hazards regression was used to analyze the prognostic factors affecting the PFS of patients and to assess the effect of the timing of combination therapies on PFS. Results: In total, 85 patients from 4 study centers were included in this study. The median PFS was 10.3 months [95% confidence interval (CI): 9.47-11.13 months], the ORR was 44.7%, the DCR was 75.3%, and the median OS was not reached. The multivariate Cox proportional hazards regression analysis showed that the early combination of chemotherapy with a PD-1 inhibitor provided better PFS than the late combination [hazard ratio (HR) 0.40, 95% CI: 0.24-0.67, P=0.001]. Lymph node metastasis (HR 2.04, 95% CI: 1.24-3.38, P=0.005), and previous treatment (HR 1.79, 95% CI: 1.09-3.00, P=0.023) were also independent risk factors for PFS. During the treatment and follow-up periods, the overall incidence of adverse events in this study was 56.5%, and that of grade ≥3 adverse events was 12.9%. Thrombocytopenia, neutropenia, anemia, and hypothyroidism were the main treatment-related adverse events, all of which were tolerated, and no serious adverse events leading to death were observed. There were no treatment-related deaths. Conclusions: PD-1 inhibitors combined with chemotherapy have good efficacy and controllable safety in patients with advanced cervical cancer. The early combination of PD-1 inhibitors and chemotherapy may provide better survival benefits than the late combination for patients.