RECOMBINANT C1 ESTERASE INHIBITOR FOR SHORT-TERM PROPHYLAXIS IN PATIENTS WITH HEREDITARY ANGIOEDEMA

Introduction Patients with hereditary angioedema (HAE) are at risk for an acute attack after medical procedures. Short-term prophylaxis may minimize this risk. This study evaluated recombinant C1 esterase inhibitor (rhC1-INH) as short-term prophylaxis. Methods Patients with angioedema were treated with rhC1-INH prior to medical procedures/stressful life events; HAE attacks were recorded through 2 days and >2-7 days postprocedure. Results Fifty-one patients (median age, 44 years [range, 17-73 years]; 62.7% female; 92.2% HAE type 1) were included. A median rhC1-INH dose of 3075 IU (range, 2100-4200 IU) was administered as prophylaxis, median of 60 minutes prior, for 70 procedures (52.9% [n=37] dental [median, 60 minutes preprocedure]); 30.0% [n=21] surgical [median, 45 minutes preprocedure]; 15.7% [n=11] endoscopy [median, 30 minutes preprocedure, and 1.4% [n=1] stressful life event). Majority (n=48; 68.6%) of 70 cases had rhC1-INH administered 10-65 minutes preprocedure: 25 of 48 (52.1%) dental, 16 (33.3%) surgical, and 7 (14.6%) endoscopy. Nineteen (27.1%) cases involved long-term prophylaxis (danazol/tranexamic acid). Overall, 97.1% (68/70) of cases did not have an HAE attack within 2 days postprocedure; 91.4% (64/70) during >2-7 days postprocedure. For 2 attacks occurring within 2 days, rhC1-INH was administered 230 minutes and ≥24 hours preprocedure, respectively. No adverse events were reported. As a self-control group, 76.9% of 26 cases with no long-term/short-term prophylaxis preprocedure had an attack within 2 days postprocedure. Conclusions Short-term prophylaxis with rhC1-INH, administered within several hours preprocedure, was efficacious and safe in adolescents/adults and reduced the risk of an HAE attack postprocedure.