Surufatinib plus toripalimab combined with etoposide and cisplatin as first-line treatment in advanced small-cell lung cancer patients: a phase Ib/II trial

Abstract

There is still room for improvement in first-line treatment of advanced small cell lung cancer (SCLC). This trial firstly investigated efficacy and safety of antiangiogenic therapy (surufatinib) (200 mg, qd, po) plus anti-PD-1 treatment (toripalimab) (240 mg, d1, ivdrip) combined with etoposide (100 mg/m², d1-d3, iv, drip) and cisplatin (25 mg/m², d1-d3, ivdrip) for advanced SCLC as first-line treatment, which has been registered on ClinicalTrials.gov under the identifier NCT04996771. The four-drug regimen was conducted q3w for 4 cycles with maintenance therapy of surufatinib and toripalimab. The primary endpoint was progression-free survival (PFS). The secondary end points included objective response rate (ORR), disease control rate (DCR), overall survival (OS) and safety. All of the 38 patients were enrolled for safety analysis, while only 35 patients were enrolled for efficacy analysis since loss of efficacy evaluation in 3 cases after treatment. After a median follow-up of 21.3 months, the ORR was 97.1% (34/35), and the DCR and the tumor shrinkage rate were both 100% (35/35). The median PFS was 6.9 months (95% CI: 4.6 m-9.2 m) and the median OS was 21.1 months (95% CI: 12.1 m-30.1 m). The 12-month, 18-month, and 24-month OS rates were 66.94%, 51.39% and 38.54%. The occurrence rate of grade ≥3 treatment-emergent adverse events (TEAEs) was 63.2% (24/38), including neutrophil count decreased (31.6%, 12/38), white blood cell count decreased (23.7%, 9/38) and platelet count decreased (10.5%, 4/38). No unexpected adverse events occurred. This novel four-drug regimen (surufatinib, toripalimab, etoposide plus cisplatin) revealed impressive therapeutic efficacy and tolerable toxicities.

Fig. 1

Patient flowchart

Fig. 2

Treatment response and survival analysis. a Best percentage changes from baseline in target lesions; b Treatment exposure and response duration; c Change of tumor size overall time. d Kaplan–Meier curves of progression-free survival; e Kaplan–Meier curves of overall survival

Fig. 3

Biomarker analysis stratified by the baseline levels of Ki-67, NSE, ProGRP, and the status of PD-L1 expression & TMB. Tumor shrinkage rate and Kaplan–Meier curves of PFS & OS stratified by the baseline levels of a Ki-67, b NSE, c ProGRP. d Swimmer plot stratified by the status of PD-L1 expression and TMB at baseline