345. CAMRELIZUMAB AS ADJUVANT THERAPY IN RESECTED ESOPHAGEAL SQUAMOUS CELL CARCINOMA: A PHASE 2 TRIAL

Abstract

Abstract CheckMate 577 has confirmed that adjuvant immunotherapy significantly prolongs disease-free survival (DFS) in patients with resected (R0) stage II or III esophageal or gastroesophageal junction cancer who had received neoadjuvant chemoradiotherapy. However, adjuvant therapy for patients with different neoadjuvant therapies needs to be explored. Therefore, this study was designed to investigate the efficacy and safety of camrelizumab as adjuvant therapy in patients with resected (R0) esophageal squamous cell carcinoma (ESCC). This is an ongoing, non-randomized, open-label, phase 2 trial (NCT04533490) in China. ESCC patients (stage cT1b-T4aN0M0/cT1-T4aN + M0) aged 18–75 years with ECOG performance status of 0–1 was planned to be enrolled in cohort A (n = 42, with 6–12 weeks of neoadjuvant therapy) and cohort B (n = 43, without neoadjuvant therapy). Following R0 resection, adjuvant camrelizumab (200 mg Q2W) was given until tumor recurrence, metastasis, intolerable toxicity, or the completion of 12-month treatment. The primary endpoint was DFS. Secondary endpoints included overall survival, recurrence rate, 1/3/5-year DFS rates, and safety. At data cutoff (Apr 21, 2022), 17 patients were enrolled, with a median age of 65 years; 9 (53%) patients were males, and 12 (71%) had ECOG performance status of 0. There were 15 patients in cohort A (14 with neoadjuvant immunochemotherapy, and 1 with neoadjuvant chemotherapy) and 2 in cohort B. With a median follow-up of 5.5 months, DFS was not reached. A total of 14 (82.3%) patients had treatment-related adverse events, which were all grade 1–2. The most common events were reactive cutaneous capillary endothelial proliferation (11 [65%]), adrenal cortical insufficiency (3 [18%]), and interstitial pneumonia (2 [12%]). Adjuvant camrelizumab showed acceptable safety profile in patients with resected (R0) ESCC who mainly received neoadjuvant immunochemotherapy, and the efficacy was worth expecting. The study enrollment is ongoing, and further survival and safety data will be reported in the future.