Ruconest (C1 esterase inhibitor, recombinant)

Complement 1 (C1)-esterase inhibitor is a naturally occurring inhibitor of certain serine proteases (e.g., C1 complement, kallikrein, coagulation factor XIIa, plasmin) involved in the complement, coagulation (e.g., contact), and fibrinolytic systems. C1-esterase inhibitor (recombinant) is a biosynthetic preparation of human C1-esterase inhibitor.

C1-esterase inhibitor (recombinant) is a biosynthetic (recombinant DNA origin) preparation of human C1-esterase inhibitor produced from the milk of transgenic (genetically modified) rabbits. The drug is isolated and purified from rabbit milk using a series of filtration and chromatography steps to reduce the risk of viral contamination. Currently available C1-esterase inhibitor concentrates in the US include plasma-derived (Cinryze(R), Berinert(R) , Haegarda(R) ) and recombinant (Ruconest(R)) preparations.

Recombinant and plasma-derived preparations of C1-esterase inhibitor are structurally similar and produce comparable therapeutic effects.

C1-esterase inhibitor is a naturally occurring serine protease inhibitor that principally regulates the activation of the complement and intrinsic coagulation (e.g., contact system) pathways. C1-esterase inhibitor also plays a role in the fibrinolytic system. Patients with hereditary angioedema (HAE) have low plasma concentrations of endogenous or functional C1-esterase inhibitor.

Such a deficiency leads to uncontrolled activation of the complement and contact system, resulting in increased vascular permeability. Replacement therapy with C1-esterase inhibitor (recombinant) increases plasma concentrations of C1-esterase inhibitor and provides an additional source of the enzyme in patients with HAE. C1-esterase inhibitor regulates the contact system by inhibiting plasma kallikrein and coagulation factor XIIa, thus preventing formation of bradykinin, the presumed mediator of increased vascular permeability in HAE.

C1-esterase inhibitor blocks both the spontaneous activation of C1 complement and formation of activated C1 complement, suppressing the classical complement pathway. During these processes, irreversible complexes are formed between the inhibitor and its target protease; the resulting complexes are then inactivated and removed from circulation. C1-esterase inhibitor also exhibits inhibitory effects on plasmin.

C1-esterase inhibitor (recombinant) exhibits dose-dependent restoration of complement homeostasis by increasing plasma C4 (substrate for activated C1) levels in patients with HAE. A dose of 50 units/kg of C1-esterase inhibitor (recombinant) increases plasma C1-esterase inhibitor activity to concentrations exceeding 0.7 units/mL (the lower limit of normal) in patients with HAE. Pharmacokinetic studies conducted in patients with asymptomatic HAE indicate that peak plasma concentrations of C1-esterase inhibitor (recombinant) are achieved in approximately 0.3 hours and the elimination half-life of the drug is approximately 2.5 hours following administration of 50 units/kg.

The elimination half-life of C1-esterase inhibitor (recombinant) has been reported to be shorter than that of plasma-derived C1-esterase inhibitor due to differences in glycosylation.

USES: This medication is used to treat the swelling problems caused by a certain immune disease passed down through families (hereditary angioedema-HAE). HAE is caused by low levels or improper function of a natural substance produced by the body (C1-esterase inhibitor). Symptoms such as rapid swelling of the hands, feet, limbs, face, tongue, or throat can occur.

Swelling of the intestinal tract may cause symptoms such as abdominal cramps, diarrhea, or vomiting. Attacks of swelling may occur without reason. However, anxiety, stress, sickness, and surgery may trigger attacks in some people.

This medication works by increasing the level of C1-esterase inhibitor to help treat attacks of sudden swelling due to hereditary angioedema.

Generic name: C1 esterase inhibitor, recombinant
Drug class: C1 Esterase Inhibitors (Acute)
Therapeutic class: Hematological Agents

The following indications are listed for Ruconest:

• Hereditary Angioedema

Also known as: Hereditary Angioneurotic Edema.