How Haegarda works
People with hereditary angioedema have recurrent and unpredictable flare-ups of their disease. The main manifestations are swelling in the mucous membranes of the lungs and intestinal tract and under the skin.
Those with the rare condition do not have enough of an enzyme called the C1 esterase inhibitor, or they have a faulty version of it. Without a proper version, the body produces overwhelming amounts of an inflammatory substance called bradykinin, which leads to tissue swelling.
Haegarda provides the body with the C1 esterase inhibitor it needs. It keeps the levels high as the body slowly absorbs and processes it.
Haegarda is meant to be self-administered. The white, freeze-dried powder has to be dissolved in water before patients inject it.
Haegarda in clinical trials
A Phase 1/2 (NCT01576523) clinical trial looked at the pharmacokinetics (how the body processes medicine), pharmacodynamics (how the medicine affects the body), and safety of Haegarda. It found that three different doses given as twice-weekly injections under the skin for a month were safe and well tolerated in patients with type 1 or 2 hereditary angioedema. The largest dose was four times the smallest, and the middle dose twice the size of the smallest.
The two highest doses were able to keep levels of C1 esterase inhibitor above 40 percent of normal — the amount required to keep a person safe from angioedema attacks. The study also found that injecting Haegarda under the skin led to more consistent delivery of the medication than putting it directly in the bloodstream with an IV. The most common side effects were pain and swelling at the injection site.
A Phase 3 clinical trial (NCT01912456) showed that injections of 40 international units per kilogram of Haegarda reduced angioedema attacks by 89 percent, while a dose of 60 IU/kg reduced the attacks by 95 percent. The results applied to patients with either type 1 or 2 hereditary angioedema.
Forty percent of patients who received the higher dose had no attacks at all. When attacks did occur, they were generally milder and less frequent. The trial ended in 2015, with the results published in the New England Journal of Medicine.
CSL Behring conducted an extension of the Phase 3 trial (NCT02316353) to determine Haegarda’s long-term safety and efficacy. Patients who completed the trial were eligible to enroll in the long-term study, where they continued receiving the same doses for up to three years. The trial ended in September 2017. The results have yet to be published.
Haegarda is the first preventative medication for hereditary angioedema that can be injected under the skin. In 2016, the FDA approved CSL Behring’s biologics license to market the therapy in the U.S.
The most common side effects from Haegarda are pain and swelling at the injection site, hypersensitivity reactions like itchiness, rash, hives, difficulty breathing, and chest tightness, symptoms of the common cold, and dizziness.
Angioedema News is strictly a news and information website about the disease. It does not provide medical advice, diagnosis or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.