A study of neoadjuvant sintilimab combined with chemotherapy TP for locally advanced esophageal squamous cell carcinoma (ESCC).

e16038 Background: Although preoperative chemoradiotherapy is the standard of care for patients with locally advanced esophageal cancer, ESCC still has a dismal prognosis. Sintilimab, a humanized IgG4 monoclonal antibody with high affinity and specificity for PD-1, has shown promising efficacy with overall survival in ESCC in a phase II study (ORIENT-02, NCT03116152)1. KEEP-G 03 given the encouraging MPR and favorable tolerability of preoperative sintilimab in combination with triplet chemotherapy in resectable ESCC (KEEP-G 03, NCT03946969)2. This trial evaluates the feasibility and safety of preoperative sintilimab in combination with chemotherapy of TP in ESCC. Methods: This is a single-arm, single center research, phase 2 trial to assessment the efficacy and safety of asintilimab and chemotherapy of TP(Q3W 2-4 cycle) as neoadjuvant treatment of locally advanced ESCC. The key eligibility criteria was locally advanced ESCC, ECOG PS 0 or 1, and at least one measurable lesion per RESIST v1.1. aSintilimab: 200mg for 60kg, 3mg/kg for body weight < 60kg; TP: pacilitaxel 175mg/m2 plus cisplatin 75mg/m2. Primary Objectives: pCR, MPR. Secondary Objectives: R0 rate, RFS, OS, Safety (CTCAE 5.0). Exploratory Objectives: The alteration of molecular biomarkers to neoadjuvant treatment including PD-L1, TMB, DDR, etc. Results: From 1/2020 to 12/2021, 20 eligible patients were recruited in the Jiangxi Tumor Hospital, NanChang, China. Conclusions: Given the encouraging MPR and favorable tolerability, the combination of sintilimab and chemotherapy of TP could be a potentially feasible and safe neoadjuvant option for locally advanced ESCC. The trial will be continued to evaluate the feasibility of this regimen.[Table: see text][Table: see text][Table: see text]