First-line penpulimab (an anti-PD1 antibody) and anlotinib (an angiogenesis inhibitor) with nab-paclitaxel/gemcitabine (PAAG) in metastatic pancreatic cancer: a prospective, multicentre, biomolecular exploratory, phase II trial.

Metastatic pancreatic cancer (mPC) has a dismal prognosis. Herein, we conducted a prospective, multicentre, single-arm, phase II trial evaluating the efficacy and safety of penpulimab and anlotinib in combination with nab-paclitaxel/gemcitabine (PAAG) in patients with first-line mPC (NCT05493995). The primary endpoints included the objective response rate (ORR) and disease control rate (DCR), while secondary endpoints encompassed progression-free survival (PFS), overall survival (OS), and safety. In 66 patients analysed for efficacy, the best response, indicated by the ORR, was recorded at 50.0% (33/66) (95% CI, 37.4-62.6%), with 33 patients achieving partial response (PR). Notably, the DCR was 95.5% (63/66, 95% CI, 87.3-99.1%). The median PFS (mPFS) and OS (mOS) were 8.8 (95% CI, 8.1-11.6), and 13.7 (95% CI, 12.4 to not reached) months, respectively. Grade 3/4 treatment-related adverse events (TRAEs) were reported in 39.4% of patients (26/66). In prespecified exploratory analysis, patients with altered SWI/SNF complex had a poorer PFS. Additionally, low serum CA724 level, high T-cell recruitment, low Th17 cell recruitment, and high NK CD56dim cell scores at baseline were potential predicative biomarkers for more favourable efficacy. In conclusion, PAAG as a first-line therapy demonstrated tolerability with promising clinical efficacy for mPC. The biomolecular findings identified in this study possess the potential to guide the precise clinical application of the triple-combo regimen.