Rationale and Design of a Phase II Trial of Combined Serplulimab and Chemotherapy in Patients with Histologically Transformed Small Cell Lung Cancer: a Prospective, Single-arm and Multicentre Study

Aims: Transformed small cell lung cancer (T-SCLC) is a highly aggressive clinical disease with a notably poor prognosis. It most often arises from epidermal growth factor receptor (EGFR)-mutant non -small cell lung cancer (NSCLC) following treatment. To date, no standard treatment has been established for T-SCLC. Platinum-etoposide was the most commonly used regimen, but progression -free survival remains unsatisfactory. Therefore, there is an urgent unmet need to develop novel and effective strategies for this population. Our study, a multicentre, open -label, single -arm phase II clinical trial (NCT05957510), aims to evaluate the efficacy and safety of serplulimab plus chemotherapy in untreated T-SCLC patients after histological transformation. Materials and methods: In total, 36 eligible participants experiencing SCLC transformation from EGFR-mutant NSCLC will be enrolled to receive combination therapy of serplulimab, etoposide and carboplatin for four to six cycles, followed by maintenance therapy with serplulimab for up to 2 years. The primary endpoint is progression -free survival; secondary endpoints include objective response rate, overall survival and safety. Results: Enrolment started in July 2023 and is ongoing, with an estimated completion date of December 2025. Conclusions: This study aims to provide valuable insights into the efficacy and safety of combining serplulimab with chemotherapy for treating patients with TSCLC originating from EGFR-mutant NSCLC. (c) 2023 Published by Elsevier Ltd on behalf of The Royal College of Radiologists.