A Study to Evaluate the Safety and Effect of Escalating Doses of CINRYZE (C1 Inhibitor [Human])

Inclusion Criteria:

To be eligible for this protocol, subjects must:

1. Be ≥6 years of age and ≥25 kg body weight

2. Have a confirmed diagnosis of HAE with a documented history of swelling of the face, extremities, gastrointestinal tract, genitalia, or larynx and a history of at least one of the following:

   • C1 inhibitor (C1 INH) gene mutation
   • C4 level below the lower limit of the reference range
   • C1 inhibitor antigen level below the lower limit of the reference range
   • Functional C1 inhibitor level below the lower limit of the reference range
   • Family history of HAE (i.e., grandparent, parent, sibling)
3. Have a history of >1.0 HAE attack per month (average) of any severity over the 3 consecutive months prior to screening while receiving the recommended Cinryze dosing of 1000 U every 3 to 4 days via intravenous injection.
4. If an adult, be informed of the nature of the study and provide written informed consent before any study-specific procedures are performed.

OR If a child, have a parent/legal guardian who is willing and able to provide written informed consent for the child to participate in the study (with assent from the child when appropriate).

Exclusion Criteria:

To be eligible for this protocol, subjects must not:

1. Have, as determined by the investigator and/or the sponsor's medical monitor, any surgical or medical condition that could interfere with the administration of study drug or interpretation of study results.
2. Have a history of abnormal blood clotting or other coagulopathy.
3. Be taking prescription anticoagulation medication
4. Have a history of allergic reaction to Cinryze or other blood products.
5. Have participated in any other investigational drug study within the past 30 days (other than Cinryze protocols).
6. Have received any blood products (other than Cinryze) within 60days prior to screening.

7. Have any of the following laboratory values at screening:

   • Hemoglobin <8 g/dL
   • White blood cell (WBC) count <2 x 109/L or >20 x 109/L
   • Platelet count <50 x 109/L or >400 x 109/L
   • Serum aspartate aminotransferase (AST) and/or alanine aminotransferase (ALT) >2.0 x the upper limit of normal
   • Blood urea nitrogen (BUN) and/or creatinine >2.0 x the upper limit of normal
8. Be pregnant or breastfeeding