Nasal RADA16 Hydrogel Application Decreases Epistaxis Severity Scores in Adults with Hereditary Hemorrhagic Telangiectasia Open Access

• RADA16 hydrogel reduced epistaxis severity score and improved anemia-related lab parameters.

• RADA16 hydrogel may be a safe and effective conservative option for epistaxis in HHT.

More than 90% of adults with hereditary hemorrhagic telangiectasia (HHT) experience epistaxis, which can be recurrent and cause significant morbidity. RADA16 is a self-assembling peptide hydrogel approved by the FDA for hemostasis and wound healing. In this cohort study, we assessed the effectiveness of nasal RADA16 application in controlling HHT-related epistaxis. A retrospective chart review was performed on a cohort of adult patients who received nasal RADA16 without any other changes in treatment. Pre- and post-Epistaxis Severity Scores (ESS), hemoglobin, and hematocrit were collected to assess treatment response. Of the included patients (n=22), there were 26 applications of RADA16. The cohort was 54.5% male, 86.4% Caucasian, had a mean age of 55.5, and predominantly ACVRL1 genotype (40.9%). Baseline mean ESS was 5.0 and decreased by an average of 2.0 at an average of 46.9 days post-treatment, which is 2.8 times more than the minimal clinically important difference for ESS in HHT (0.71). The mean baseline hemoglobin (n=13) and hematocrit (n=10), were 11.3 g/dL and 37.5%, respectively, and did not exhibit significant changes post-RADA16. No bleeding, pain, or allergic reactions occurred due to the application. Several patients reported mild nasal congestion. Our experience demonstrates that RADA16 can be considered as a safe epistaxis treatment modality for HHT that is easy to apply and does not require the operating suite.