C1 esterase inhibitor

Subjects were to assess their symptoms every 15 minutes up to 4 hours after the initial dose or until substantial relief of the defining symptom was achieved. The conservative analysis defined substantial relief as 3 consecutive assessments of improvement of the defining symptom; any attack that did not have 3 consecutive documented reports of improvement was considered a treatment failure. In the less conservative analysis, attacks also were considered to have responded if clinical improvement of the defining symptom occurred but data were incomplete due to cessation of symptom assessments.

A hereditary angioedema (HAE) attack was defined as a discrete episode during which the subject progressed from no angioedema to symptoms of angioedema.

Randomized subjects assessed their symptoms every 15 minutes up to 4 hours after the initial dose of blinded study drug or until substantial relief of the defining symptom was achieved. Substantial relief was defined as 3 consecutive assessments of improvement of the defining symptom. Beginning of substantial relief was considered the first of the 3 consecutive assessments.

An HAE attack was defined as the subject-reported indication of swelling at any location following a report of no swelling on the previous day. Analyses include observed attack counts and normalized attack counts (i.e., the number of attacks observed during each therapy period, normalized for the number of days the subject participated in that period).

Defined as either a new focal neurological impairment, or a decrease of at least 2 points on the Glasgow Coma Scale. This should last for at least 1 hour, is not apparent immediately after aneurysm occlusion, and cannot be attributed to other causes by means of clinical assessment, CT or MRI scanning of the brain, and appropriate laboratory studies.

Complication rate during hospitalization

The protocol-specified Day 20 (post-treatment) biopsy was compared to the qualifying biopsy to assess changes in histopathology for light and immunofluorescence microscopy. The Central Pathologist provided the following categorical information from the qualifying biopsy in an AMR Scorecard: C4d Score (0-100), Margination Score (0-100) Glomerulitis Score (0-100), Vasculitis Score (0-100), Glomerulosclerosis Score (0-100), Chronic Glomerulopathy Score (0-100), Interstitial Fibrosis Score (0-100), and the Chronic Vasculitis Score (0-100), with 0 being absence of abnormal histopathology. The "qualifying" renal allograft biopsy was performed as standard of care (SOC) within 12 months after transplant and prior to screening for this study. The first dose of study drug (Day 1) was administered within 72 hours after qualifying biopsy. A negative change from baseline indicates that histopathology has improved. Endpoint includes subjects with both Qualifying and Day 20 Biopsies.