247P Efficacy of adebrelimab with chidamide, gemcitabine, and S-1 in locally advanced or metastatic pancreatic cancer: A phase II study

Methods: Pts with PD-L1+ mNSCLC and progression after 1 prior anti-PD-L1 tx were enrolled to acasunlimab (Arm A: 100 mg Q3W x2 cycles then 500 mg Q6W) or acasunlimab with pembrolizumab (pembro) to maximize PD-1 blockade (Arm B: 100 mg + pembro 200 mg Q3W; Arm C: 100 mg + pembro 400 mg Q6W).Tumor PD-L1 status (TPS 1%) was centrally assessed (PD-L1 IHC 22C3 PharmDx).Primary endpoint: ORR; other endpoints: PFS, OS, safety. Results: As of Dec 2, 2024, 125 pts (87 centrally PD-L1+; 65 Ph3-eligible) were dosed: 22 (16; 11) in Arm A, 42 (26; 22) in Arm B, 61 (45; 32) in Arm C. In Arm C, 49.2% of ITT pts and 53.1% of Ph3-eligible pts remained on trial at data cutoff.Baseline pt and tumor characteristics across arms were similar.Most common TRAEs in ITT (all grades; n, %) were asthenia (21, 16.8%); AST increased (18, 14.4%); ALT increased (16, 12.8%); diarrhea (16, 12.8%); fatigue (16, 12.8%); and decreased appetite (13; 10.4%).Transaminase elevations were mostly grade 1-2 and generally manageable.Time-to-event and response outcomes are presented in the table.Table.Time-toevent and response outcomes in CPI-treated mNSCLC.Conclusions: Acasunlimab plus pembro showed promising OS and durable benefit in PD-L1+ mNSCLC post-CPI (Arm C 12 mo OS rate of 64%).Safety was manageable, with generally reversible hepatic events.The Q6W regimen offered better tolerability, durability of response, and survival, supporting its evaluation in the ongoing Ph3 trial (NCT06635824).