OUTCOMES FOLLOWING USE OF SUBCUTANEOUS C1-INHIBITOR DURING PREGNANCY IN PATIENTS WITH HEREDITARY ANGIOEDEMA

Introduction In women with hereditary angioedema (HAE) due to C1-inhibitor (C1-INH) deficiency, pregnancy can have a variable effect on disease activity. C1-INH concentrate is recommended as first-line therapy for pregnant patients with HAE. Subcutaneous C1-INH (HAEGARDA®, CSL Behring) is indicated for routine prophylaxis to prevent HAE attacks in adolescents and adults. This analysis examines outcomes in patients who became pregnant during C1-INH (SC) treatment in an open-label safety study. Methods Per study protocol, patients who became pregnant during treatment were required to discontinue the study. These patients were assessed during exposure to C1-INH in the open-label study and followed post-discontinuation to assess pregnancy outcomes. Results Four patients discontinued the study due to pregnancy as mandated by the protocol. C1-INH (SC) exposure after the last menstrual period ranged from 4 to 8 weeks (9, 10, 10, and 15 doses). Pregnancy was normal in all cases, with no related complications. All 4 women delivered live healthy infants, 1 by vaginal delivery and 3 by caesarean section at 36 to 40 weeks gestation. No congenital abnormalities were reported. With twice-weekly C1-INH (SC) treatment in the open-label study (total exposure: 25.3-43.1 weeks), 3 women had ≥50% reduction in HAE attacks relative to the number used to qualify for study entry. Three patients had Conclusions In this study, patients with HAE who were exposed to C1-INH (SC) during the first trimester of pregnancy had normal pregnancy outcomes, and all delivered healthy newborns.