FDA approves first subcutaneous C1 Esterase Inhibitor to treat rare genetic disease.

June 22, 2017

The U.S. Food and Drug Administration approved Haegarda, the first C1 Esterase Inhibitor (Human) for subcutaneous (under the skin) administration to prevent Hereditary Angioedema (HAE) attacks in adolescent and adult patients.

The subcutaneous route of administration allows for easier at-home self-injection by the patient or caregiver, once proper training is received.

HAE, which is caused by having insufficient amounts of a plasma protein called C1-esterase inhibitor (or C1-INH), affects approximately 6,000 to 10,000 people in the U.S. People with HAE can develop rapid swelling of the hands, feet, limbs, face, intestinal tract or airway. These attacks of swelling can occur spontaneously, or can be triggered by stress, surgery or infection.

Haegarda is a human plasma-derived, purified, pasteurized, lyophilized (freeze-dried) concentrate prepared from large pools of human plasma from U.S. donors. Haegarda is indicated for routine prophylaxis to prevent HAE attacks, but is not indicated for treatment of acute HAE attacks.

C1 Esterase Inhibitor
C1-INH is a soluble, single-chain highly glycosylated protein containing 478 amino acid residues which belongs to the serine protease inhibitor (serpin) family. All plasma used in the manufacturing of C1-INH is obtained from U.S. donors and is tested
using serological assays for hepatitis B surface antigen and antibodies to HIV-1/2 and HCV. Additionally, the plasma is tested with Nucleic Acid Testing (NAT) for HBV, HCV, HIV-1 and HAV and found to be non-reactive (negative). The plasma is also tested by NAT for Human Parvovirus B19. Only plasma that has passed virus screening is used for production, and the limit for Parvovirus B19 in the fractionation pool is set not to exceed 104 IU of Parvovirus B19 DNA per mL.
The manufacturing process for HAEGARDA includes multiple steps that reduce the risk of virus
transmission. The virus inactivation/reduction capacity consists of three steps:

 Pasteurization in aqueous solution at 60C for 10 hours 
 Hydrophobic interaction chromatography
 Virus filtration (also called nanofiltration) by two filters, 20 nm and 15 nm, in series


The efficacy of Haegarda was demonstrated in a multicenter controlled clinical trial. The study included 90 subjects ranging in age from 12 to 72 years old with symptomatic HAE. Subjects were randomized to receive twice per week subcutaneous doses of either 40 IU/kg or 60 IU/kg, and the treatment effect was compared to a placebo treatment period. During the 16 week treatment period, patients in both treatment groups experienced a significantly reduced number of HAE attacks compared to their placebo treatment period.’


The most common side effects included injection site reactions, hypersensitivity (allergic) reactions, nasopharyngitis (swelling of the nasal passages and throat) and dizziness. Haegarda should not be used in individuals who have experienced life-threatening hypersensitivity reactions, including anaphylaxis, to a C1-INH preparation or its inactive ingredients.

Haegarda received Orphan Drug designation, which provides incentives to assist and encourage the development of drugs to treat rare diseases or conditions.

The FDA granted approval of Haegarda to CSL Behring LLC.