 A multicentre study to investigate pharmacokinetics, clinical efficacy and safety of nanofiltered Cetor called C1-esteraseremmer-N during the development phase for the treatment of hereditary angioedema HAE will be performed. This study KB2003.01 consists of three parts, part A pharmacokinetics phase II, part B treatment of attacks of angioedema phase III and part C prophylactic use of C1 inhibitor phase III. Part B C will provide data on the efficacy of C1-esteraseremmer-N. 