Intranasal Bevacizumab for HHT-Related Epistaxis

Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant genetic disorder characterized by systemic vascular malformations that result from mutations of the ENG gene, which encodes for factors in the vascular endothelial growth factor (VEGF) pathway. HHT is diagnosed by the Curacao Criteria including the presence of epistaxis; telangiectasias or vascular malformations in the lungs, liver, or nervous system; and a positive family history involving a first-degree relative. One of the most common presentations of this disease is recurrent and profound epistaxis, with many patients reporting more than 4 epistaxis episodes in a day, many lasting up to an hour. HHT-related epistaxis often results in severe anemia requiring intravenous iron and repeated blood transfusions, and also carries significant psychosocial disability relating to impaired quality of life and work absenteeism. Multiple approaches to treatment have been described, including electrocautery, laser treatment, embolization, septodermoplasty, and as a last resort, Young's procedure, involving closure of the nasal vestibule. These approaches are largely palliative, with variable effectiveness, and almost always require repeated procedures for chronic management of bleeding. There is a great need for the development of new treatment options for reducing the medical morbidity and quality of life impairment associated with refractory epistaxis in HHT.

Recently there has been promising data suggesting that inhibition of angiogenesis may be an effective strategy for managing HHT-related bleeding. Circulating concentrations of VEGF are significantly elevated in HHT, making VEGF an attractive therapeutic target. Preliminary studies suggest that bevacizumab, a recombinant monoclonal antibody that inhibits the biologic activity of VEGF, can significantly improve epistaxis severity when topically applied, locally injected, or intravenously administered. However, these early pilot studies of bevacizumab have been limited exclusively to retrospective case series. As yet, there has been no prospective double-blind placebo controlled trial with serial follow up time points to establish the role of bevacizumab in the treatment of HHT-related epistaxis.

Based on existing level 4 evidence that suggests that bevacizumab injection is beneficial in the management of HHT-related epistaxis, we hypothesize that patients who receive intranasal injection with bevacizumab at the time of electrocautery treatment will have an improvement in the frequency and severity of epistaxis compared to patients who receive injection of saline control.