What is kallikrein (kininogenase)?

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From the FDA Drug Label

The kallikrein-kinin system is a complex proteolytic cascade involved in the initiation of both inflammatory and coagulation pathways One critical aspect of this pathway is the conversion of High Molecular Weight (HMW) kininogen to bradykinin by the protease plasma kallikrein. KALBITOR is a potent (Ki = 25 pM), selective, reversible inhibitor of plasma kallikrein. By directly inhibiting plasma kallikrein, KALBITOR reduces the conversion of HMW kininogen to bradykinin and thereby treats symptoms of the disease during acute episodic attacks of HAE.

Kallikrein is a protease that plays a critical role in the kallikrein-kinin system, which is involved in the initiation of both inflammatory and coagulation pathways.

  • The drug KALBITOR (ecallantide) is a potent, selective, and reversible inhibitor of plasma kallikrein.
  • By inhibiting plasma kallikrein, KALBITOR reduces the conversion of HMW kininogen to bradykinin, thereby treating symptoms of Hereditary Angioedema (HAE) during acute episodic attacks 1.

From the Research

Kallikrein inhibitors, such as ecallantide, are the most effective treatment for acute attacks of hereditary angioedema, with a significant reduction in symptom severity and improvement in quality of life 2.

Kallikrein Overview

Kallikrein is a group of serine proteases that play important roles in various physiological processes, particularly in the kallikrein-kinin system that regulates blood pressure, inflammation, and pain responses. There are two main types: plasma kallikrein, which circulates in the blood, and tissue kallikrein, found in organs like the kidneys, pancreas, and salivary glands.

Kallikrein Inhibitors

Kallikrein inhibitors, such as ecallantide, are used therapeutically to treat hereditary angioedema attacks. Ecallantide is a novel, specific, and potent inhibitor of plasma kallikrein that has been approved for the treatment of acute attacks of hereditary angioedema in patients aged 16 years and older 3. The recommended dose is 30 mg given as three separate subcutaneous injections 2.

Clinical Evidence

Clinical trials have demonstrated the efficacy and safety of ecallantide in treating acute HAE episodes. For example, a phase III clinical trial found that ecallantide significantly improved symptom severity and quality of life in patients with acute HAE attacks compared to placebo 4. Another study found that ecallantide was well tolerated and effective in reducing symptom severity in patients with HAE 5.

Treatment Considerations

When developing individualized HAE management plans, patient-specific and drug-specific factors should be considered. Optimization of HAE therapy will require further integration of new therapies into the current treatment paradigm 6.

Key Points

  • Kallikrein inhibitors, such as ecallantide, are effective in treating acute attacks of hereditary angioedema.
  • Ecallantide is a novel, specific, and potent inhibitor of plasma kallikrein.
  • The recommended dose of ecallantide is 30 mg given as three separate subcutaneous injections.
  • Clinical trials have demonstrated the efficacy and safety of ecallantide in treating acute HAE episodes.

References

Research

Ecallantide for treatment of acute attacks of hereditary angioedema.

American journal of health-system pharmacy : AJHP : official journal of the American Society of Health-System Pharmacists, 2012

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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