IBI343 Combined With Chemotherapy in Advanced Pancreatic Cancer

This is a Phase Ib/II study to evaluate the safety, tolerability and efficacy of IBI343 in combination with chemotherapy in patients with advanced pancreatic cancer, including a Phase Ib safety introduction and Phase II expansion phase. In phase Ib (safe introduction phase), participants with CLDN18.2-positive advanced pancreatic adenocarcinoma (PAC) who had previously received first-line gemcitabine-based systemic therapy were enrolled to receive IBI343 in combination with chemotherapy.A classic "3+3" dose-escalation design was used to determine the dose of the combination therapy, including the following two cohorts: Cohort A: received IBI343+ capecitabine TBD mg/m2 BID PO×14d Q3W; Cohort B: received IBI343+ capecitabine TBD mg/m2 BID PO×14d Q3W+ oxaliplatin TBD mg/m2 IV Q3W (each subject received up to 8 cycles of oxaliplatin). In cohort A, 3 subjects were enrolled in Intravenous (IV) Q3W, and the starting dose of IBI343 was 6 mg/kg.The preset starting dose of capecitabine was 750mg/m2 BID PO, D1-14, Q3W. The observation period of safe introduction of DLT was 21 days (3 weeks) after the first administration, and IBI343 was administered only once during the DLT observation period.If the first 3 subjects did not develop DLT during the DLT observation period, 3-6 subjects were allowed to receive IBI343 6mg/kg combined with capecitabine 1000mg/m2 BID PO, D1-14, Q3W;If DLT occurs in 1 of these 3 subjects, the other 3 subjects will be included in the same dose group.If no DLT occurred in the three additional subjects, 3-6 subjects were allowed to receive IBI343 6mg/kg combined with capecitabine 1000mg/m2BID PO, D1-14, Q3W;If DLT occurred in ≥1 of the 3 subjects included in the supplement, or ≥2 of the 6 subjects in total, or ≥2 of the first 3 subjects, 3 to 6 subjects were allowed to receive IBI343 4.5mg/kg Q3W;If intolerance remains, the mode and dose of administration will be further discussed. If the dose level of 1000mg/m2 in combination with capecitabine is co