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 CD4⁺Foxp3⁺ Treg cells, and increased perivascular CD4⁺ T cells, CD39⁺CD8⁺ 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).