Efficacy and Safety of FOLFIRI/aflibercept in Second-line Treatment of Metastatic Colorectal Cancer in a Real-world Population: Prognostic and Predictive Markers

Purpose: The phase III VELOUR trial demonstrated efficacy with combined FOLFIRI-aflibercept in patients with metastatic colorectal cancer previously treated with oxaliplatin with or without bevacizumab versus placebo. The effect of FOLFIRI-aflibercept in routine clinical practice was evaluated.

Methods/patients: Overall survival (OS), progression-free survival (PFS), response and safety were analysed for 78 patients treated with FOLFIRI-aflibercept at six GITuD institutions. Exploratory analyses of prognostic and predictive markers of efficacy were performed.

Results: Patients had good general status (PS 0-1 96.2%), tumours were mostly RAS-mutant (75.6%), synchronous (71.8%), and left-sided (71.8%). Prior therapy included bevacizumab (47.4%) and anti-EGFR agents (12.8%). PFS was longer for metachronous than synchronous tumours (11.0 vs 5.0 months, P = 0.028), and for left-colon tumours (7.0 vs 3.0 months, P = 0.044). RAS-mutant status, first-line treatment and primary tumour surgery did not impact PFS. The disease control rate was 70.5%. The most common grade 3/4 toxicities were neutropenia (15.3%), asthenia (10.3%), diarrhea and mucositis (6.4% each). Dysphonia was reported in 39.7% of patients, and grade 3 hypertension in 3.8%. Development of hypertension (any grade) was significantly associated with a reduced risk of progression by multivariate analysis (HR = 2.7; 95%CI 1.3-5.4; P = 0.001).

Conclusions: Efficacy with FOLFIRI-aflibercept in a real-life population was in line with results from the pivotal trial and toxicity was manageable with treatment adaptation. Survival outcomes were not impacted by primary tumour location, RAS-mutant status, first-line treatment or primary tumour surgery. Hypertension may be a surrogate marker of efficacy in this patient population.