Haegarda (C1 Esterase Inhibitor Subcutaneous [Human]) for Hereditary Angioedema

Haegarda (C1 esterase inhibitor subcutaneous [human]) is a prescription medication approved by the U.S. Food and Drug Administration (FDA) for routine prevention of hereditary angioedema (HAE) attacks in people 6 years of age and older.

How Haegarda Works and How It’s Taken

Haegarda is a C1 esterase inhibitor replacement treatment. It replaces a blood protein that is missing or does not work properly in people with hereditary angioedema.

Haegarda inactivates proteins called kallikrein and factor XIIa. This is thought to reduce the production of bradykinin, a substance that can cause blood vessels to leak fluid and lead to swelling.

Doctors prescribe Haegarda to help prevent HAE attacks in people 6 years of age and older.

Haegarda is injected under the skin twice weekly, every three or four days. After proper training, a person with HAE or caregivers may give it at home.

Choose an injection site on the abdomen or another area recommended by your healthcare provider. Use a different site each time. A new site should be at least 2 inches, or 5 centimeters, from the last injection site. Do not inject into skin that is itchy, red or discolored, swollen, painful, or bruised. Avoid scars and stretch marks.

Each vial is for one-time use and contains no preservative. After mixing, use the solution right away or within eight hours. Keep the mixed solution at room temperature. Do not refrigerate or freeze it. Throw away any unused solution.

Typical Dosing for HAE

The recommended dose of Haegarda for HAE is 60 international units per kilogram of body weight. It is injected under the skin twice weekly, every three or four days.

The dose is based on body weight.

This information is based on prescribing information, but your healthcare provider may tailor your treatment plan. Always follow their guidance.

Haegarda Side Effects

In clinical studies, the most common side effects of Haegarda occurred in about 5 percent to 31 percent of people. These include:

Injection site reactions (such as pain, swelling, itching, rash, bruising, warmth, or skin discoloration where the shot is given)
Hypersensitivity (allergic-type reactions such as itching, rash, or hives)
Nasopharyngitis (coldlike symptoms such as a runny or stuffy nose, sneezing, or watery eyes)
Dizziness

Serious Side Effects and Warnings

Haegarda can cause serious side effects that may require immediate medical attention. These include:

Hypersensitivity (allergic) reactions — These reactions may include a severe whole-body allergic reaction or anaphylaxis, which can include hives, chest tightness, trouble breathing or wheezing, low blood pressure.
Thromboembolic events (blood clots) — Clots in veins or arteries can lead to problems like deep vein thrombosis, pulmonary embolism, heart attack, or stroke. Stroke symptoms may include pain, swelling, warmth, or discoloration in an arm or leg, sudden shortness of breath, chest pain that worsens with deep breathing, a fast heartbeat, or sudden weakness or numbness on one side of the body.
Risk of transmitting infections from human blood products — Because Haegarda is made from human blood, there is a risk of transmitting viruses or other infectious agents despite careful screening and processing.

Get medical help right away if you think you are having a serious reaction.

How To Save on Haegarda

CSL Behring LLC, the manufacturer of Haegarda, offers Haegarda Connect. Eligible people with commercial insurance may be able to receive copay support.

Haegarda Connect also offers personalized support from a dedicated case manager, self-administration training from a nurse for people with HAE, parents, and caregivers, insurance navigation, and access to the Haegarda QuickStart Program.

To learn more, visit the Haegarda Connect website or call 844-HAEGARDA.

What To Know Before Taking Haegarda

Before using Haegarda, tell your doctor if you have had blood clots or have risk factors for blood clots. These may include:

Heart or blood vessel disease
A previous stroke or blood clot
An indwelling catheter in a vein
Inability to move for a long time
Use of birth control pills or certain androgens

Tell your doctor about all medicines you take, including prescription drugs, over-the-counter medicines, vitamins, and herbal supplements.

Do not use Haegarda if you have had a life-threatening allergic reaction, including anaphylaxis, to a C1 esterase inhibitor product.

If you miss a dose of Haegarda, call your healthcare provider.

If you are pregnant, planning to become pregnant, or breastfeeding while taking Haegarda, talk with your doctor about the risks and benefits.

Community FAQs

These answers are fact-checked by our editorial staff.

How effective is Haegarda for HAE?

In a study of adults and adolescents with symptomatic type 1 or 2 HAE, people who received Haegarda at 60 international units per kilogram had an average of 0.52 attacks per month. They had 4.03 attacks per month while receiving placebo.

Compared with placebo, the median reduction in attack rate was 95 percent with 60 international units per kilogram and 89 percent with 40 international units per kilogram. In the study, 40 percent of people receiving 60 international units per kilogram had no HAE attacks during the treatment period.

How long does Haegarda take to work for HAE?

Haegarda is used regularly to help prevent HAE attacks. It is not used to treat an attack after it starts.

After twice-weekly injections of 60 international units per kilogram, the median time to reach the highest blood level was 59 hours. This does not show exactly how soon Haegarda begins preventing attacks. The studies measured prevention over several weeks.

Should I take Haegarda for HAE if I have an infection?

There are no specific instructions about stopping or avoiding Haegarda because of an infection. Because Haegarda is made from human plasma, it may carry a risk of transmitting infectious agents, although donor screening, testing, and manufacturing steps are used to reduce that risk.

If you think you may have an infection related to treatment, contact your healthcare provider.

Can I self-administer Haegarda for HAE?

Yes. Haegarda can be self-administered under the skin after a healthcare provider has trained you and confirmed that you can give the injection correctly. A trained caregiver may also give Haegarda.

Do not try to prepare or inject Haegarda until your healthcare provider has taught you how. Always follow the instructions provided by your healthcare provider and the instructions for use.