Perioperative sintilimab and neoadjuvant anlotinib plus chemotherapy for resectable non-small-cell lung cancer: a multicentre, open-label, single-arm, phase 2 trial (TD-NeoFOUR trial).

This open-label, single-arm, phase 2 trial evaluated the efficacy and safety of neoadjuvant sintilimab combined with anlotinib and chemotherapy, followed by adjuvant sintilimab, for resectable NSCLC. Forty-five patients received anlotinib (10 mg, QD, PO, days 1-14), sintilimab (200 mg, day 1), and platinum-based chemotherapy of each three-week cycle for 3 cycles, followed by surgery within 4-6 weeks. Adjuvant sintilimab (200 mg) was administered every 3 weeks. The primary endpoint was achieving a pathological complete response (pCR). From June 10, 2021 through October 10, 2023, 45 patients were enrolled and composed the intention-to-treat population. Twenty-six patients (57.8%) achieved pCR, and 30 (66.7%) achieved major pathological response (MPR). Forty-one patients underwent surgery. In the per-protocol set (PP set), 63.4% (26/41) achieved pCR, and 73.2% achieved MPR. The median event-free survival was not attained (95% CI, 25.1-NE). During the neoadjuvant treatment phase, grade 3 or 4 treatment-related adverse events were observed in 25 patients (55.6%), while immune-related adverse events were reported in 7 patients (15.6%). We assessed vascular normalization and infiltration of immune-related cells by detecting the expression of relevant cell markers in NSCLC tissues with mIHC. Significant tumor microenvironment changes were observed in pCR patients, including reduced VEGF cells and CD4Foxp3 Treg cells, and increased perivascular CD4 T cells, CD39CD8 T cells, and M1 macrophages. In conclusion, perioperative sintilimab and neoadjuvant anlotinib plus chemotherapy achieved pCR in a notable proportion of patients with resectable NSCLC and were associated with profound changes in the tumour microenvironment (ClinicalTrials.gov NCT05400070).