Summary: This study is designed to evaluate the safety after switching to garadacimab from another prophylactic hereditary angioedema (HAE) treatment (marketed kallikrein \[KK\] inhibitor or plasma-derived C1-esterase inhibitor \[pdC1INH\]prophylactic) when administered once monthly for approximately 3 months in participants aged greater than or equal to (\>=) 12 years with HAE.

Summary: This is a multinational, multicenter, prospective, observational cohort study of patients with HAE in the real-world setting. The study will include patients newly initiating garadacimab in routine clinical practice. Each participant will be followed for 48 months after index date (date of the first administration of garadacimab). Patient data will be collected from the HAE eDiary, patient medical...