151P CO-STAR: Surgical Conversion Feasibility Trial of Sintilimab (PD-1 Inhibitor) Combined with Doublet Chemotherapy (Nab-Ptx & S-1) and Apatinib (Anti-Angiogenic TKI) for the First-Line Treatment of Stage IV Gastric Cancer (GC)

BackgroundPD-1 inhibitor & chemotherapy is the standard 1L-therapy of GC with a dismal OS. Retrospective studies suggested that conversion therapy & surgery could prolong life and even cure stage IV GC patients (pts). Given the combination mechanism of PD-1 inhibitor, chemo, and TKIs, this prospective, single-arm, phase II trial was designed to assess the surgical conversion feasibility of this regimen in stage IV GC.MethodsTreatment-naïve pts with histopathologically confirmed stage IV (AJCC8th) GC and ECOG PS 0-1 were enrolled. After receiving sintilimab (200mg, iv, d1), Nab-PTX (non-peritoneal metastasis: 260 mg/m2, iv, d1; peritoneal metastasis: 200 mg/m2, iv, d1 and 60 mg/m2, ip, d1), S-1 (60mg, po, bid, d1-14), and apatinib (250mg, po, qd) Q3W, pts were assessed for tumor response and surgical feasibility by radiologic imaging & MDT Q2-4W. The primary endpoint was ORR and R0 surgical conversion rate.ResultsTable: 151PResponse & Surgical conversion, n (%)N = 47ORRPR29 (61.7)DCR46 (97.9)SD17 (36.2)PD1 (2.1)R0 conversion rate28 (59.6)Pathological responsepCR5/29 (17.2)MPR7/29 (24.1) Open table in a new tab ConclusionsThese results above showed this regimen was feasible and tolerable for surgical conversion of stage IV GC pts. Sintilimab, doublet chemotherapy, and apatinib might offer an opportunity of life-prolonging or cure for this population. Trial ID: NCT04267549.Clinical trial identificationNCT04267549.Legal entity responsible for the studyTianjin Medical University Cancer Institute and Hospital.FundingInnovent Biologics Co. Ltd.DisclosureAll authors have declared no conflicts of interest. BackgroundPD-1 inhibitor & chemotherapy is the standard 1L-therapy of GC with a dismal OS. Retrospective studies suggested that conversion therapy & surgery could prolong life and even cure stage IV GC patients (pts). Given the combination mechanism of PD-1 inhibitor, chemo, and TKIs, this prospective, single-arm, phase II trial was designed to assess the surgical conversion feasibility of this regimen in stage IV GC. PD-1 inhibitor & chemotherapy is the standard 1L-therapy of GC with a dismal OS. Retrospective studies suggested that conversion therapy & surgery could prolong life and even cure stage IV GC patients (pts). Given the combination mechanism of PD-1 inhibitor, chemo, and TKIs, this prospective, single-arm, phase II trial was designed to assess the surgical conversion feasibility of this regimen in stage IV GC. MethodsTreatment-naïve pts with histopathologically confirmed stage IV (AJCC8th) GC and ECOG PS 0-1 were enrolled. After receiving sintilimab (200mg, iv, d1), Nab-PTX (non-peritoneal metastasis: 260 mg/m2, iv, d1; peritoneal metastasis: 200 mg/m2, iv, d1 and 60 mg/m2, ip, d1), S-1 (60mg, po, bid, d1-14), and apatinib (250mg, po, qd) Q3W, pts were assessed for tumor response and surgical feasibility by radiologic imaging & MDT Q2-4W. The primary endpoint was ORR and R0 surgical conversion rate. Treatment-naïve pts with histopathologically confirmed stage IV (AJCC8th) GC and ECOG PS 0-1 were enrolled. After receiving sintilimab (200mg, iv, d1), Nab-PTX (non-peritoneal metastasis: 260 mg/m2, iv, d1; peritoneal metastasis: 200 mg/m2, iv, d1 and 60 mg/m2, ip, d1), S-1 (60mg, po, bid, d1-14), and apatinib (250mg, po, qd) Q3W, pts were assessed for tumor response and surgical feasibility by radiologic imaging & MDT Q2-4W. The primary endpoint was ORR and R0 surgical conversion rate. ResultsTable: 151PResponse & Surgical conversion, n (%)N = 47ORRPR29 (61.7)DCR46 (97.9)SD17 (36.2)PD1 (2.1)R0 conversion rate28 (59.6)Pathological responsepCR5/29 (17.2)MPR7/29 (24.1) Open table in a new tab ConclusionsThese results above showed this regimen was feasible and tolerable for surgical conversion of stage IV GC pts. Sintilimab, doublet chemotherapy, and apatinib might offer an opportunity of life-prolonging or cure for this population. Trial ID: NCT04267549. These results above showed this regimen was feasible and tolerable for surgical conversion of stage IV GC pts. Sintilimab, doublet chemotherapy, and apatinib might offer an opportunity of life-prolonging or cure for this population. Trial ID: NCT04267549.