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.

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. 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. Enrolment started in July 2023 and is ongoing, with an estimated completion date of December 2025. This study aims to provide valuable insights into the efficacy and safety of combining serplulimab with chemotherapy for treating patients with T-SCLC originating from EGFR -mutant NSCLC. • T-SCLC is a highly aggressive disease with a poor prognosis and lacks standard treatment. • Adding immunotherapy to chemotherapy might improve outcomes for T-SCLC but lacks clinical evidence. • The first prospective trial to investigate the efficacy of serplulimab plus chemotherapy for T-SCLC. • The exploratory analysis aims to identify potential biomarkers for immunotherapy in T-SCLC. [ABSTRACT FROM AUTHOR]