Sintilimab plus anlotinib as second or further-line therapy for extensive disease small cell lung cancer: a phase 2 investigator-initiated non-randomized controlled trial.

Background: Treatment options remain rather limited for extensive disease small cell lung cancer (ED-SCLC) patients in second or further-line setting. Methods: The phase 2 investigator-initiated non-randomized study enrolled patients who had disease progression on at least one line of platinum-based chemotherapy. Participants received intravenous sintilimab 200 mg on day one and oral daily anlotinib 12 mg on days 1-14 once every three weeks per cycle. The primary endpoint was progression-free survival (PFS). The secondary endpoints included overall survival (OS), objective response rate (ORR), disease control rate (DCR) and safety. This study is registered with ClinicalTrials.gov (NCT04055792). Findings: Forty-two patients were enrolled between August 29, 2019 and December 26, 2021 at Henan Cancer Hospital in China. 37 patients were evaluable for efficacy. The median follow-up was 24.8 months (IQR: 16.9-28.2). The median PFS was 6.1 months (95% CI: 5.0-7.3). The OS was 12.7 months (95% CI: 7.1-18.2). The ORR was 56.8% (21/37, 95% CI: 40.0-73.5) and the DCR was 89.2% (33/37, 95% CI: 78.7-99.7). Forty patients (40/42, 95%) had at least one treatment-related adverse event (TRAE). Immune-related adverse events (irAEs) were reported in 39 patients (39/42, 93%), while grade 3 or higher irAEs occurred in 11 patients (11/42, 26%). The most frequent irAEs were hypothyroidism (16/42, 38%), elevated gamma-glutamyl transpeptidase (15/42, 36%) and elevated creatine kinase MB (15/42, 36%). The most frequent grade 3 or higher irAEs were elevated gamma-glutamyl transpeptidase (5/42, 12%) and increased aspartate aminotransferase (3/42, 7%). Interpretation: Sintilimab plus anlotinib demonstrated promising antitumor activities as second or further-line therapy for ED-SCLC and had manageable toxicities. The findings support further randomized controlled trials of this combination regimen for ED-SCLC. Funding: Henan Province Health and Youth Subject Leader Training Project, Henan Health Science and Technology Innovation Talents, ZHONGYUAN QIANREN JIHUA, Henan International Joint Laboratory of drug resistance and reversal of targeted therapy for lung cancer, Tumor Research Fund of Anti-Angiogenesis Targeted Therapy of China Anti-Cancer Association.