Observational Safety Study for KALBITOR (Ecallantide) in the Treatment of Acute Attacks of Hereditary Angioedema

Occurrence of Anaphylaxis or Other Adverse Events Suggestive of Hypersensitivity

Based on medical review of multiple preferred terms for treatment emergent adverse events (TEAEs) suggestive of Type 1 hypersensitivity; terms included adverse drug reaction, anaphylaxis, anaphylactic reaction, anaphylactoid reaction, hypersensitivity, erythema, flushing, hot flush, pharyngeal edema, laryngeal edema, pruritus, pruritus generalized, rash, rash erythematous, rhinitis allergic, rhinorrhea, throat irritation, urticaria, urticaria localized, dyspnea, and wheezing. Records of patients with any of these TEAE referred terms were reviewed further to assess potential hypersensitivity reactions, considering factors such as timing of TEAEs in relationship to dose (ie, occurred within 24 hours after start of KALBITOR treatment), accompanying symptoms, Investigator causality assessment (ie, reported as possibly, probably, or definitely related to study drug), and any other available clinical information. Anaphylaxis subset determined based on criteria established by the NIAID.

Time frame: 12 months after first treatment

Occurrence of Seroconversion to Anti-ecallantide Antibodies Upon Exposure to KALBITOR.

Seroconversion is the development of detectable specific antibodies in the blood serum. Serum was tested for development of antibodies (irrespective of immunoglobulin class) against ecallantide at screening and at all safety evaluations. Positive results were to undergo a confirmatory test. Confirmed positive samples were further titered. Patients who developed an antibody response were evaluated for the development of neutralizing antibodies. Patients also had their serum analyzed for IgE-specific antibodies to ecallantide at screening and during safety evaluations. Positive results underwent a confirmatory test. Confirmed positive samples were further titered.

Time frame: 12 months after first treatment

Occurrence of Adverse Events Related to Disordered Coagulation (Hypercoagulability and Hypocoagulability) Upon Exposure to KALBITOR

Events of ecchymosis, hemorrhage, petechiae, spontaneous hemorrhage, hematoma, gastrointestinal bleeding, hemorrhagic stroke and any other term indicative of a bleeding event or increased tendency for bleeding were reviewed to determine the occurrence of hypocoagulability. Events of clotting, thrombosis, pulmonary embolism, vaso-occlusive stroke, myocardial infarction, and any other term indicative of a clotting event or increased risk of clotting were reviewed to determine the occurrence of hypercoagulability.