Safety and Efficacy Study of CINRYZE for Prevention of Angioedema Attacks in Children Ages 6-11 With Hereditary Angioedema

Angioedema attack was defined as the participant-reported indication of symptoms or signs such as swelling or pain at any location following a report of no swelling or pain on the previous day. Manifestations of an attack that progress from one site to another, prior to complete resolution, was considered a single attack. Attacks that began to regress and then worsened before complete resolution was also considered one attack. Attacks that began then appeared to resolve and then reappeared without a symptom-free calendar day reported after the appearance of resolution were considered 1 attack. Any events of swelling due to trauma or symmetrical nonpainful swelling of the lower extremities were not considered an angioedema attack. The number of attacks was normalized for the number of days participants participated in a given period and expressed as the monthly frequency.

Severity of the angioedema attack sign/symptom was characterized as None: no symptom; Mild: noticeable symptom but easily tolerated by the participant and did not interfere with routine activities; Moderate: symptom interfered with the participant's ability to attend school or participate in family life and social/recreational activities; Severe: symptom significantly limited the participant's ability to attend school or participate in family life and social/recreational activities. Symptom severity score was assigned as Mild = 1, Moderate = 2 and Severe = 3. Cumulative attack severity score was the sum of the maximum symptom severity scores recorded for each angioedema attack in a treatment period. Cumulative attack-severity score normalized per month [(raw score/number of days of participation in that treatment period)*30.4] was reported here. Cumulative attack-severity score normalized per month ranged from 0 to 10.4 and higher scores represent worse symptoms.

Severity of the angioedema attack sign/symptom was characterized as None: no symptom; Mild: noticeable but easily tolerated by the participant and did not interfere with routine activities; Moderate: interfered with the participant's ability to attend school or participate in family life and social/recreational activities; Severe: significantly limited the participant's ability to attend school or participate in family life and social/recreational activities. Symptom severity score was assigned as Mild = 1, Moderate = 2 and Severe = 3. Cumulative daily-severity score was the sum of the severity scores recorded for every day of reported symptoms in a treatment period. Cumulative daily-severity score normalized per month [(raw score/number of days of participation in that treatment period)*30.4] was reported here. Cumulative daily-severity score normalized per month ranged from 0 to 15.6 and higher scores represent worse symptoms.

Angioedema attack was defined as the participant-reported indication of symptoms or signs such as swelling or pain at any location following a report of no swelling or pain on the previous day. Manifestations of an attack that progress from one site to another, prior to complete resolution, was considered a single attack. Attacks that began to regress and then worsened before complete resolution was also considered one attack. Attacks that began then appeared to resolve and then reappeared without a symptom-free calendar day reported after the appearance of resolution were considered 1 attack. Any events of swelling due to trauma or symmetrical nonpainful swelling of the lower extremities were not considered an angioedema attack. The number of attacks requiring acute treatment was normalized for the number of days participants participated in a given period and expressed as the monthly frequency.

An adverse event (AE) was any untoward, undesired, unplanned clinical event in the form of signs, symptoms, disease, or laboratory or physiological observations occurring in a participant participating in a clinical study with the sponsor's product, regardless of causal relationship. TEAEs were defined as events that started or worsened on or after the date and time of the first dose of investigational product and up to 7 days after the last dose of investigational product.

C1 INH antigen concentration in plasma was determined using an automated nephelometric assay.

The functional activity of C1 INH in plasma samples was determined by a chromogenic assay.

Concentration of Complement C4 in plasma was determined using an automated nephelometric assay.

The presence of C1 INH antibodies in plasma samples was determined using a proprietary enzyme-linked-immunosorbent-assay. Number of participants with C1 INH Antibodies was reported.