Tislelizumab with anlotinib and chemotherapy for second-line treatment of pancreatic ductal adenocarcinoma: A pilot study early result.

e16316 Background: Advanced pancreatic ductal adenocarcinoma is a malignant tumor with poor prognosis. At present, chemotherapy is still the standard treatment, however the efficacy is unsatisfied. The lack of second-line treatment options for pancreatic cancer results in progression-free survival often lasting less than 3 months. For pancreatic cancer is an immune desert type of tumor, immunotherapy has not brought breakthrough therapeutic regimen compared to the remarkable data in other tumors.There is still insufficient therapeutic evidence treated with PD1 antibody in pancreatic cancer. Anlotinib is a tyrosine kinase inhibitor (TKI) with anti-tumor effects. It has been shown the combination of PD1 and multi-target tyrosine kinase inhibitors can increase immunotherapy efficacy. The purpose of this study is to evaluate the efficacy and tolerability of Tislelizumab combined with Anlotinib, as well as chemotherapy (the choice of the investigator) in second-line treatment of patients with pancreatic ductal adenocarcinoma. Methods: In this single arm, phase II, prospective exploratory study, it was planned to recruit 30 adult patients with treated pancreatic ductal adenocarcinoma who have never received any PD (L) 1 and TKI. Eligible patients received Tislelizumab (iv, 200mg, Q3W), Anlotinib (PO, 10mg, QD), and chemotherapy (determined by the researchers) till disease progression or death. The primary endpoint was median progression-free survival (mPFS), the secondary endpoints were objective response rate (ORR), median overall survival(mOS), disease control rate (DCR), and treatment safety profile. Results: 14 eligible patients were recruited till Jan 2024, 12 patients with PFS records were included. Median follow-up time was 208 days (104 days-504 days). mPFS was 106 days, OS is not reached, BOR (best of response) was stable disease. The 3-months DCR rate was 58.3%, 6-months DCR rate was 25%. One patient was observed to have a 20% tumor shrinkage after two cycles of treatment and is still being followed up. The most common treatment-related adverse events(TRAEs) was neutropenia with level ≤grade 3, observed in 8/14 patients. The immune-related adverse event of concern was hypothyroidism(grade 1/2), which occurred in two patients. Two patients experienced grade 4 obstructive jaundice caused by the progression of the disease. Conclusions: The second-line combination regimen of Tislelizumab with Anlotinib based on chemotherapy demonstrated survival improvement trend and no new safety signals identified in pancreatic cancer. These data suggest Tislelizumab + Anlotinib+Chemo may be a promising novel treatment option for patients with pancreatic cancer. Clinical trial information: NCT05681390 .