To assess the efficacy of recombinant human C1-esterase inhibitor in the management of HAE prodrome for preventing the progression from prodrome to an acute angioedema attacks. Subjects will either receive Ruconest after the first 2 prodromes or during the last 2 prodromes. 5 clinic visits will occur within 24 hours of a prodrome. Subjects will complete prodrome severity and angioedema attack diaries

After screening, subjects will be followed in the study for four consecutive prodromes. For prodromes designed to be treated with Ruconest, the drug will be administered within 12 hours of prodromal onset and prior to the onset of objective selling. Ruconset will be self-administered at home or by a healthcare professional at the recommended dose of 50 IU/kg body weight with maximum dose of 4200 IU as a slow IV injection over 5 minutes Subjects will be randomized into two arms after enrollment. Subjects in Arm A receives Ruconest after 1st and 2nd prodrome and no Ruconest after 3rd and 4th prodromes. Subjects in Arm B receive no Ruconest after 1st and 2nd prodrome and Ruconest after 3rd and 4th prodromes.

Inclusion Criteria:

• Prior diagnosis of HAE Type 1 and 2,
• One or more HAE attacks per month,
• History of 4 prodromes that proceed to angioedema attacks

Exclusion Criteria:

• History of thrombosis or arterial/venous thromboembolic attacks
• History of atherosclerosis, morbid obesity, immobility
• History of allergy to rabbits or products from rabbits
• History of life-threatening immediate allergic reactions to C1 esterase inhibitor preparations

not needed for manuscript