Camrelizumab combined with ablation and chemotherapy for pancreatic cancer with liver metastases: A single-arm, phase II, prospective clinical study.

TPS4169 Background: Pancreatic cancer represents one of the most aggressive tumors and the majority of patients receive a diagnosis of metastatic disease, mainly in the liver, leading to poor prognosis and survival. Currently, chemotherapy has been the treatment of choice for fit patients with pancreatic cancer liver metastases (PCLM), reaching a median survival of about 5 to 7 months. In addition, local ablation of the metastatic tumors, by increasing neoantigen exposure and transforming the immune microenvironment to reduce the progression of liver metastases, might increase the survival benefit of patients. Camrelizumab, an anti-PD-1 monoclonal antibody, has obtained preliminary results in metastatic pancreatic cancer. Therefore, this study aims to explore the effectiveness and safety of camrelizumab combined with ablation and chemotherapy in the treatment of PCLM. Methods: In this single-arm, prospective, phase II study, 34 patients with histological or cytological diagnosis of PCLM, ECOG performance score of 0-1, no prior chemotherapy or the interval of adjuvant chemotherapy ≥6 months, plan to be enrolled. The enrolled patients first received ablation surgery of liver metastases, then chemotherapy (the standard regimen for advanced pancreatic cancer, determined by the investigator) combined with camrelizumab (200 mg, iv, q3w) is administered 1 week after ablation. If the patient has multiple metastatic tumors, the ablation needs to be performed in stages. The treatment regimens will continue until the disease progression, unacceptable toxicity or withdrawal of consent. The primary endpoint is 6-month progress-free survival (6-month PFS) rate (per RECIST v1.1 by researcher). Secondary endpoints are objective response rate, disease control rate, progression-free survival, overall survival and safety. On the basis of a threshold 6-month PFS rate of 25%, targeting an expected 6-month PFS rate of 44% and assuming 18 months follow-up, 80% power and a one-sided α = 0.05, this design requires 34 evaluable patients to be accrued over 2 years. Clinical trial information: NCT04420130.