Phase II study of anlotinib in combination with oxaliplatin and capecitabine for patients with RAS/BRAF wild-type metastatic colorectal adenocarcinoma as the first-line therapy

Abstract

Background: Anlotinib, an oral small molecule tyrosine kinase inhibitor targeting VEGFR 1/2/3, FGFR 1-4, PDGFR a/β, and c-kit, had demonstrated prolonged progression-free survival (PFS) in refractory metastatic colorectal cancer (mCRC). This multicenter, single-arm, phase II, exploratory study was conducted to evaluate the efficacy and safety of anlotinib combined with capecitabine and oxaliplatin as first-line treatment for unresectable RAS/BRAF wild-type mCRC.

Methods: Patients aged 18-75 with RAS/BRAF wild-type unresectable mCRC, without prior systemic treatment, and ECOG performance status ≤1 were enrolled. Eligible patients received capecitabine (850 mg/m², p.o., bid, on day 1-14 every 21 days), oxaliplatin (130 mg/m², i.v., on day 1 every 21 days), and anlotinib (12 mg, p.o., qd, on days 1-14 every 21 days) as induction therapy. Following 6 cycles of therapy, patients who achieved response or stable disease received capecitabine and anlotinib as maintenance therapy until tumor progression. The primary endpoint was objective response rate (ORR) according to RECIST (version: 1.1), and the secondary endpoints were PFS, disease control rate (DCR), duration of response (DOR), and safety.

Results: Between November 2019 and February 2021, 31 patients were enrolled. One patient was excluded for refusing treatment. The primary endpoint of ORR was 76.7% (95% CI, 57.7-90.1) with 1 patient achieving a complete response and 22 patients partial response. DCR was 93.3% (95% CI, 77.9-99.2). At a median follow-up of 14.1 months (95% CI, 9.9-18.3), median PFS was 11.3 months (95% CI, 7.1-14.1), and DOR was 7.9 months (95% CI, 5.5-12.7). Twenty-five (83.3%) patients experienced grade 3 or 4 treatment-emergent adverse events (TEAEs). No grade 5 TEAE was reported. The most common grade 3 or 4 TEAEs (>10%) were hypertension (15/30; 50%), neutrophil count decreased (8/30; 26.7%), and diarrhea (4/30; 13.3%). A total of 18 (60%) patients had TEAEs that resulted in dose reduction, interruptions, or delays.

Conclusions: Anlotinib combined with capecitabine and oxaliplatin showed considerable ORR, DCR, PFS, and DOR in the first-line therapy of mCRC with manageable toxicity profiles.

Trial registration: ClinicalTrials.gov : NCT04080843.

Keywords: Anlotinib; Capecitabine; First-line therapy; Metastatic colorectal cancer; Oxaliplatin.