FRONTiER: A feasibility trial of nivolumab with neoadjuvant CF or DCF, FLOT therapy for locally advanced esophageal carcinoma (JCOG1804E)—Short-term results for cohorts C and D.

Abstract

286 Background: The standard neoadjuvant chemotherapy (NAC) in Japan for locally advanced esophageal squamous cell carcinoma (ESCC) consists of CDDP + 5-FU (CF). Recently, neoadjuvant DTX plus CF (DCF) therapy has shown promising efficacy for locally advanced ESCC. In addition, immune checkpoint inhibitors (ICIs) have demonstrated a survival benefit in ESCC and potential as an NAC in several cancers, including lung, breast, skin, and bladder. We previously reported that neoadjuvant CF plus nivolumab (Nivo) therapy was tolerable and showed promising efficacy for ESCC; however, the efficacy of ICI with DCF as an NAC and the safety of subsequent surgery for ESCC patients remain unclear. Methods: FRONTiER is a multi-cohort phase I study designed to evaluate the safety and efficacy of ICI combined with NAC in ESCC. The eligibility criteria were histologically proven ESCC with cT1N1-3M0 or cT2-3N0-3M0 (8th-UICC TNM classification), patient age of 20-75 years, PS ≤1, and no prior cancer therapies. The primary endpoint was the incidence of dose-limiting toxicities (DLT) from the initial dose to the 30th postoperative day. This study contained 5 experimental cohorts: cohort C received 3 courses of DTX (70 mg/m2), CDDP (70 mg/m2), and Nivo (360 mg/body) on day 1 and 5-FU (750 mg/m2) on days 1–5 every three weeks. Cohort D received one administration of Nivo (240 mg/body) 2 weeks before chemotherapy followed by the same regimen as cohort C. Results: Twelve patients were enrolled in cohort C (n = 6) and D (n = 6) (median age [range]: 60 [31-74] years, PS 0/1: 11/1, clinical stage I/II/III/IVA: 2/2/7/1). Only one patient in cohort D developed DLT (grade 3 dyspnea and rash); no other DLT were seen. Grade ≥3 adverse events were neutropenia (n = 1), leukopenia (n = 7), anorexia (n = 3), hyponatremia (n = 2), febrile neutropenia (n = 1), nausea (n = 1), and lymphopenia (n = 1) during NAC, and lung infection (n = 2), peritoneal infection (n = 1), anemia (n = 1), lymph leakage (n = 1), vagal reflex (n = 1), dyspnea (n = 1), rash (n = 1), septic shock (n = 1), pleural effusion (n = 1), and pneumatosis intestinalis (n = 1) during the postoperative period. No treatment-related deaths were observed. All patients received 3 courses of NAC, and 11 patients (91.7%) achieved an R0 resection without treatment interruption. One patient (16.7%) in cohort C and 3 patients (50.0%) in cohort D achieved pathological complete responses. Conclusions: Neoadjuvant DCF + Nivo with/without prior Nivo administration followed by surgery for locally advanced ESCC was well tolerated and showed an extremely promising efficacy. Clinical trial information: NCT03914443.