147P - Serplulimab combined with chemotherapy in the neoadjuvant treatment of resectable oesophageal squamous cell carcinoma: A single-arm phase II trial

Background

In resectable esophageal squamous cell carcinoma (ESCC), there is limited evidence of the efficacy of serplulimab in combination with chemotherapy followed by minimally invasive esophagectomy. Therefore, we aimed to observe and evaluate its efficacy and safety in locally advanced ESCC.

Methods

Patients aged 18-75 years and classified as stage II-IVA according to the 8th edition of the American Joint Committee on Cancer (AJCC) staging manual, who were histologically or cytologically diagnosed with ESCC, were deemed eligible to participate in this trial. Patients received 3 cycles of neoadjuvant therapy with serplulimab (4.5mg/kg intravenously on day 1), carboplatin (AUC=5 intravenously on day 1), albumin paclitaxel (260 mg/m2 intravenously on day 1); each cycle was repeated every 21 days. Surgery occurred 4-6 weeks after the last neoadjuvant treatment cycle. The primary outcome was the pathological complete response (PCR) rate of the tumour and lymph nodes. This prospective, single-arm, phase 2 trial was conducted at the Second Affiliated Hospital of Zhejiang University in China.

Results

A total of 48 patients were enrolled in this study, with no observed disease progression during the neoadjuvant treatment phase. The disease control rate and objective response rate were 100.0% and 68.8%, respectively. Most of the adverse events were grade 1-2, 2 (4.2%) patients experienced grade 3 adverse events. Three patients refused to receive surgical treatment and declined to participate in the study. Consequently, 45 patients received minimally invasive esophagectomy. All 45 patients achieved R0 resection, with 14 patients (31.1%) attaining a PCR for both the tumour and lymph nodes.

Conclusions

The administration of serplulimab in conjunction with chemotherapy in the neoadjuvant setting for locally advanced ESCC has demonstrated promising antitumor activity and an acceptable safety profile in this single-arm study. Extended follow-up to assess survival outcomes and a phase 3 randomized trial are necessary to further evaluate the efficacy and safety of the proposed treatment regimen.

Clinical trial identification

NCT05659251.

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.