Toripalimab combined with concurrent platinum-based Chemoradiotherapy in patients with locally advanced cervical Cancer: an open-label, single-arm, phase II trial.

Background: Concurrent chemoradiotherapy is currently the standard of care for patients with locally advanced cervical cancer. However, even with the application of modern radiotherapy techniques, a considerable number of patients still develop distant metastases. PD-L1 inhibitors show good efficacy in cervical cancer. This single-arm phase II study aims to explore the efficacy and tolerability of combining PD-L1 inhibitor with concurrent chemoradiotherapy in the treatment of locally advanced cervical cancer.

Methods/design: The primary endpoint of the study was the objective response rate assessed according to RECIST v1.1 criteria. The inclusion criteria were previously untreated patients aged 18-75 years with stage III-IVA (FIGO 2018 staging system) locally advanced cervical cancer. During concurrent chemoradiotherapy and consolidation chemotherapy, the enrolled patients will receive toripalimab (240 mg) every 3 weeks. After consolidation chemotherapy, the enrolled patients will be treated with toripalimab (240 mg) once every 6 weeks until the whole treatment cycle reaches 1 year. Intensity modulated radiotherapy was used for external beam radiation, and high-dose rate brachytherapy was delivered under image-guidance. Weekly DDP (40 mg/m) was given concurrently with radiotherapy while 6 cycles of consolidated chemotherapy (paclitaxel plus DDP) were given after radiotherapy every three weeks. Secondary objectives included safety and tolerability, toxicity profile, progression-free survival, and overall survival.

Discussion: PD-L1 inhibitor has shown good efficacy in recurrent/metastatic cervical cancer. However, there is still a lack of evidence about its combination with concurrent chemoradiotherapy in the treatment of locally advanced cervical cancer. The purpose of this study is to explore the efficacy and tolerance of this combination therapy, so as to lay the foundation for the future phase III randomized study.

Trial Registration:  clinicaltrials.gov NCT05084677 . Retrospectively registered on Octorber 07, 2021.