C1 Inhibitor, Human

Pronunciation: (in-HIB-a-tor)
Class: Protein C1 inhibitor

Trade Names

Berinert
- Injection, lyophilized powder for solution 500 units

Cinryze
- Injection, lyophilized powder for solution 500 units

Pharmacology

Regulates the activation of the complement and intrinsic coagulation (contact system) pathway and also regulates the fibrinolytic system.

Pharmacokinetics

Absorption

C _max is 0.68 units/mL and T _max is 3.9 h ( Cinryze ).

Distribution

V _ss is 11.1 to 56.1 mL/kg ( Berinert ).

Elimination

Half-life is 56 h ( Cinryze ); 7.4 to 24.4 h ( Berinert ).

Special Populations

Renal Function Impairment

Pharmacokinetic studies have not been conducted in patients with renal impairment.

Hepatic Function Impairment

Pharmacokinetic studies have not been conducted in patients with hepatic impairment.

Children

Compared with adults, the half-life was shorter and Cl was faster ( Berinert ).

Indications and Usage

Berinert

Treatment of acute abdominal or facial attacks of hereditary angioedema in adult and adolescent patients.

Cinryze

Routine prophylaxis against angioedema attacks in adolescent and adult patients with hereditary angioedema.

Contraindications

Life-threatening, immediate hypersensitivity reactions, including anaphylaxis, to these products.

Dosage and Administration

Adults and adolescents

IV

Berinert

20 units/kg body weight.

Cinryze

1,000 units every 3 or 4 days.

General Advice

• Consult manufacturer's prescribing information for preparation and administration guidelines.
• Administer Cinryze at a rate of 1 mL/min.
• Administer Berinert by slow IV injection at a rate of 4 mL/min.
• Product is for single use only; discard partially used vials.
• Do not mix with other materials or medicinal products.

Storage/Stability

Berinert

Store at 36° to 77°F. Do not freeze. Protect from light. Use reconstituted solution promptly or within 8 h if stored up to 77°F. Do not refrigerate or freeze the reconstituted solution.

Cinryze

Store at 36° to 77°F. Do not freeze. Protect from light. Use reconstituted solution within 3 h of reconstitution.

Drug Interactions

None well documented.

Laboratory Test Interactions

None well documented.

Adverse Reactions

CNS

Headache (11%).

Dermatologic

Pruritus; rash.

GI

Abdominal pain, nausea (7%); diarrhea, dysgeusia, vomiting (5%).

Local

Pain on injection, redness at injection site (postmarketing).

Musculoskeletal

Muscle spasms (6%); back pain, limb injury, pain in extremities.

Respiratory

Bronchitis, sinusitis, upper respiratory tract infections, viral upper respiratory tract infection.

Miscellaneous

Pain (6%); nasopharyngitis (5%); chills, fever, hypersensitivity/anaphylactic reactions, shock (postmarketing).

Precautions

Monitor Monitor all patients for thrombotic and hypersensitivity reactions.

Pregnancy

Category C .

Lactation

Undetermined.

Children

Safety and efficacy not established in children younger than 13 yr of age.

Hypersensitivity

Severe hypersensitivity reactions may occur.

Infections

Because C1 inhibitor is prepared from human blood, there is a risk of transmitting infectious agents (eg, viruses), including Creutzfeldt-Jakob disease.

Thrombotic events

Have been reported when used off-label at high doses.

Overdosage

Symptoms

Overdosage has not been reported.

Patient Information

• Instruct patients to immediately report the following to their health care provider: signs and symptoms of allergic hypersensitivity reactions, such as anaphylaxis, hives, hypotension, tightness of the chest, urticaria, and wheezing, or signs and symptoms of thrombosis, such as altered consciousness or speech, loss of sensation or motor power, new onset of swelling and pain in the limbs or abdomen, new-onset chest pain, or shortness of breath.
• Advise female patients to notify their health care provider if they become pregnant or intend to become pregnant during C1 inhibitor therapy.
• Advise patients to notify their health care provider if they are breast-feeding or plan to breast-feed.
• Advise patients to bring an adequate supply of medication when travelling.
• Inform patients of the risk and benefits of taking medications made from human blood.

Copyright © 2009 Wolters Kluwer Health.