The armamentarium for LTP of HAE attacks has considerably expanded since 2017, with a subcutaneous formulation of plasma‐derived C1‐INH (pdC1‐INH) approved in the United States in 2017 and the European Union (EU; approval date varies per country),11, 12 subcutaneous monoclonal antibody against plasma kallikrein lanadelumab approved both in the United States and the EU in 2018,13, 14 and oral kallikrein inhibitor berotralstat approved in the United States in 2020 and in the EU in 2021.15, 16. Here, KLK4 is linked to hereditary angioedema.