Efficacy and Safety Study of DX-88 to Treat Acute Attacks of Hereditary Angioedema (HAE)

A Double-blind, Placebo-controlled Study (72 Patients, Randomized 1:1) Followed by a Repeat-dosing Phase to Assess the Efficacy and Safety of DX-88 (Ecallantide; Recombinant Plasma Kallikrein Inhibitor) for the Treatment of Acute Attacks of Hereditary Angioedema

The purpose of this study is to determine if a subcutaneous dose of DX-88 (ecallantide; an investigational product) is safe and relieves symptoms of HAE in patients suffering from moderate to severe acute attacks of HAE.

Inclusion Criteria:

• Age 10 and older
• Documented diagnosis of HAE, Type I or II
• Executed informed consent
• Presentation for treatment within 8 hours of patient recognition of moderate to severe HAE attack

Exclusion Criteria:

• Receipt of investigational drug or device, other than DX-88, within 30 days of treatment
• Receipt of non-investigational C1-INH (C1 esterase inhibitor) within 7 days of treatment
• Diagnostic of acquired angioedema, estrogen-dependent angioedema or drug induced angioedema
• Pregnancy or breastfeeding
• Patients who have received DX-88 within 7 days of presentation for dosing in the Double-blind Phase