Plasma VEGF - a candidate biomarker for response to treatment with bevacizumab in HHT patients.

Abstract

Recurrent epistaxis is the principal symptom of hereditary hemorrhagic telangiectasia (HHT). Currently, there is no standard therapy for this condition. Bevacizumab (anti-VEGF) treatment has been under intense investigation but treatment effects vary greatly between individuals. There are currently no markers to predict anti-VEGF therapeutic response in HHT patients. We evaluated plasma VEGF levels in 13 HHT patients and correlated values with i) degree of epistaxis, measured by visual analog scale (VAS), epistaxis severity score (ESS), and patient bleeding diaries ii) the prevalence of extranasal manifestations, iii) the HHT subtype and iv) the treatment response to intranasal submucosal bevacizumab. Plasma VEGF was elevated in all 13 HHT patients compared to reference levels and showed a moderate correlation with VAS and duration of moderate bleeding events. In patients treated with intranasal submucosal bevacizumab plasma VEGF levels showed a strong correlation with the degree of reduction of mild bleeding events and VAS. The role of plasma VEGF as a potential predictive biomarker for therapeutic response to bevacizumab treatment warrants further investigation in larger prospective studies.