Biomaterial Database

Treatment of hereditary angioedema with a vapor-heated C1 inhibitor concentrate. 1996

A T Waytes, and F S Rosen, and M M Frank

Laboratory of Clinical Investigation, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Md, USA.

BACKGROUND Hereditary angioedema results from a congenital deficiency of functional C1 inhibitor and is characterized by episodic bouts of edema, which may be life-threatening when they involve the larynx. We evaluated the effectiveness of a C1 inhibitor concentrate in the prevention and treatment of attacks of hereditary angioedema. The concentrate was vapor-heated to inactivate hepatitis and human immunodeficiency viruses. METHODS We conducted two double-blind, placebo-controlled studies. The first was a crossover study consisting of two 17-day trials in which prophylactic infusions of either C1 inhibitor (25 plasma units per kilogram of body weight) or placebo were given intravenously every third day to six patients with hereditary angioedema. The second study was conducted in patients with acute attacks of hereditary angioedema and assessed the length of time to a clinical response after infusions of either 25 plasma units of C1 inhibitor per kilogram (55 infusions in 11 patients) or placebo (49 infusions in 11 patients). RESULTS The infusions of C1 inhibitor concentrate resulted in close to normal functional levels of C1 inhibitor and C4. As compared with placebo, prophylactic infusions of C1 inhibitor resulted in significantly lower daily symptom scores for the severity of edema of the extremities (P<0.01), larynx (P<0.05), abdomen (P<0.05), and genitourinary tract (P<0.05). Likewise, during the treatment study the time from the start of an infusion to the beginning of improvement in symptoms was shorter for the C1 inhibitor infusions than the placebo infusions (55 vs. 563 minutes, P<0.001). There was no evidence of toxicity. CONCLUSIONS Infusions of a vapor-heated C1 inhibitor concentrate are a safe and effective means of both preventing attacks of hereditary angioedema and treating acute attacks.

UI	MeSH Term	Description	Entries
D003174	Complement C1 Inactivator Proteins	Serum proteins that inhibit, antagonize, or inactivate COMPLEMENT C1 or its subunits.	Complement 1 Esterase Inhibitors,Complement C1 Inactivating Proteins,Complement C1 Inhibiting Proteins,Complement C1 Inhibitor Proteins,Complement C1r Protease Inhibitor Proteins,Complement C1s Esterase Inhibitor Proteins,Complement Component 1 Inactivator Proteins
D004311	Double-Blind Method	A method of studying a drug or procedure in which both the subjects and investigators are kept unaware of who is actually getting which specific treatment.	Double-Masked Study,Double-Blind Study,Double-Masked Method,Double Blind Method,Double Blind Study,Double Masked Method,Double Masked Study,Double-Blind Methods,Double-Blind Studies,Double-Masked Methods,Double-Masked Studies,Method, Double-Blind,Method, Double-Masked,Methods, Double-Blind,Methods, Double-Masked,Studies, Double-Blind,Studies, Double-Masked,Study, Double-Blind,Study, Double-Masked
D006358	Hot Temperature	Presence of warmth or heat or a temperature notably higher than an accustomed norm.	Heat,Hot Temperatures,Temperature, Hot,Temperatures, Hot
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000799	Angioedema	Swelling involving the deep DERMIS, subcutaneous, or submucosal tissues, representing localized EDEMA. Angioedema often occurs in the face, lips, tongue, and larynx.	Quincke's Edema,Urticaria, Giant,Angioneurotic Edema,Angioedemas,Angioneurotic Edemas,Edema, Angioneurotic,Edema, Quincke's,Edemas, Angioneurotic,Giant Urticaria,Giant Urticarias,Quincke Edema,Quinckes Edema,Urticarias, Giant
D013242	Sterilization	The destroying of all forms of life, especially microorganisms, by heat, chemical, or other means.
D016896	Treatment Outcome	Evaluation undertaken to assess the results or consequences of management and procedures used in combating disease in order to determine the efficacy, effectiveness, safety, and practicability of these interventions in individual cases or series.	Rehabilitation Outcome,Treatment Effectiveness,Clinical Effectiveness,Clinical Efficacy,Patient-Relevant Outcome,Treatment Efficacy,Effectiveness, Clinical,Effectiveness, Treatment,Efficacy, Clinical,Efficacy, Treatment,Outcome, Patient-Relevant,Outcome, Rehabilitation,Outcome, Treatment,Outcomes, Patient-Relevant,Patient Relevant Outcome,Patient-Relevant Outcomes
D018592	Cross-Over Studies	Studies comparing two or more treatments or interventions in which the subjects or patients, upon completion of the course of one treatment, are switched to another. In the case of two treatments, A and B, half the subjects are randomly allocated to receive these in the order A, B and half to receive them in the order B, A. A criticism of this design is that effects of the first treatment may carry over into the period when the second is given. (Last, A Dictionary of Epidemiology, 2d ed)	Cross-Over Design,Cross-Over Trials,Crossover Design,Crossover Studies,Crossover Trials,Cross Over Design,Cross Over Studies,Cross Over Trials,Cross-Over Designs,Cross-Over Study,Crossover Designs,Crossover Study,Design, Cross-Over,Design, Crossover,Designs, Cross-Over,Designs, Crossover,Studies, Cross-Over,Studies, Crossover,Study, Cross-Over,Study, Crossover,Trial, Cross-Over,Trial, Crossover,Trials, Cross-Over,Trials, Crossover