Andembry (garadacimab-gxii) is a biologic medicine used to prevent hereditary angioedema (HAE) attacks in adults and adolescents. During an HAE attack, swelling under the skin happens in different areas of the body. While swelling in the throat area is not particularly common, when throat swelling does occur, it can be deadly since it can close off your airway. Certain situations or triggers can cause these attacks to happen. Common triggers for attacks include stress, surgery, medical or dental procedures, infections, and tiredness. People with HAE have to take medicine to prevent these attacks from occurring and also need to have a rescue medicine readily available to treat any breakthrough attacks.
Andembry was approved in June 2025 to prevent HAE attacks in people 12 and older. It is the only activated factor XII (factor XIIa) inhibitor on the market used to prevent HAE attacks. Andembry is not used as a rescue medicine to treat breakthrough HAE attacks, but it can lower the number of attacks that happen.
How Does Andembry Work for Hereditary Angioedema?
Andembry is a monoclonal antibody that blocks the production of a protein called factor XIIa. Blocking factor XIIa lowers the production of an inflammatory substance in the body known as bradykinin, which is usually high in people with HAE. Bradykinin is linked to inflammation and swelling in HAE attacks. Lowering the amount of inflammatory bradykinin in the body helps to lower the number of HAE attacks that people have.
How Should I Use Andembry?
Andembry is a liquid injected under the skin. Andembry is given once initially, and then once every month after that as an injection under the skin.
Andembry is injected into the thighs or stomach area by you or a caregiver at home. A caregiver may also inject the medicine into the back of the upper arm. Do not inject into areas of the skin that are tender, bruised, red, or hard, or that have moles or scars. Each injection should be given at a different site on your body. Do not inject within 2 inches around your belly button.
Andembry comes in two forms for injection under the skin. The most common form is a prefilled device that is ready to use, so you do not need to learn how to use a syringe and needle. The medicine also comes in a prefilled syringe with a needle safety device. In either case, if your health care provider decides you can give your injections at home, they will give you instructions and teach you how to give yourself the injection. The medicine is stored in the refrigerator. To make the injection more pleasant, it is helpful to let it warm up to room temperature before using it.
It is important to inject the medicine properly so that you get the right dose. Your prescription should come with “Instructions for Use,” which explains how to prepare and give a dose. Ask your pharmacist or other health care provider if you are unsure how to use Andembry.
How Was Andembry Studied for Hereditary Angioedema?
One clinical study known as VANGUARD looked at whether Andembry was safe and effective for preventing HAE attacks over a six-month period. Andembry was compared to a placebo that contained no medicine. People in the studies did not know if they were getting Andembry or placebo.
The VANGUARD study included 64 people who were 12 or older with a diagnosis of HAE. Andembry or a placebo was given as an injection into the skin on the first day, and then once every month for five doses. The average age of people in the study was about 41. About 60% of people in the study were female and 40% were male. Eighty-six percent of the people were White, 9% were Japanese, 2% were Black or African American, 2% were Native Hawaiian or Other Pacific Islander, and 2% were categorized as another race. To be included in the study, people were not allowed to take any other preventive medicine for HAE and had to have had at least three HAE attacks during the three months before the study started. During the study, people were allowed to use their emergency medicine to treat any HAE attacks that occurred while taking Andembry.
At the end of the six-month study, people were allowed to continue into a longer study, which is still active. The ongoing study will continue to evaluate the safety and efficacy of Andembry for over three years.
What Benefits Were Seen with Andembry?
People who received Andembry during the study instead of placebo had significantly fewer HAE attacks per month over the six-month period. Andembry reduced the number of HAE attacks by 87% compared to placebo over six months. People had an average of 0.27 HAE attacks per month while taking Andembry and about two attacks per month while taking placebo.
During the six-month study, 62% of people who were taking Andembry were completely attack-free compared to 0% who were taking placebo. Andembry significantly reduced the amount of attacks that required emergency medicine during the study.
Almost three-quarters of people taking Andembry were attack-free during the first three months of the study.
Your results may differ from what was seen in clinical studies.
How Long Does It Take Adembry to Work?
If Andembry is working, the number of HAE attacks you experience should decrease right away. Most people taking Andembry in the study did not have an HAE attack for over two months after starting the medicine.
Do not stop using this or any other medicines for HAE without talking to your health care provider first, even if your symptoms have gotten better. Your symptoms may get worse again if you stop or change any of your medicines. Andembry may not completely stop your attacks from occurring, but it may reduce how often they happen.
Tell your health care provider if the number of attacks you have is not getting better within the first month of using Andembry. Your health care provider may talk about other options for treating this condition.
What Can I Do to Manage Side Effects?
The most common side effects of Andembry are infection in the nose or throat; sore throat; cold symptoms; stomach pain; and pain, itching, redness, or swelling where the needle went in your skin.
People taking Andembry are more likely to have infections of the nose, throat, and upper airways. The best way to prevent infection is to reduce your exposure to germs by washing your hands and staying away from people who are sick. Tell your health care provider if you have a fever or other signs of infection, such as aching, painful muscles, or feeling unwell.
If your stomach pain does not go away or becomes worse while taking Andembry, talk to your health care provider.
To limit injection site reactions such as redness, pain, swelling, and/or bruising where you get the shot, inject the medicine into a different part of the body each time, which is called “rotating” the injection site. For example, Andembry can be injected into the front of the thighs, stomach area, or back of the upper arms. Do not inject Andembry into skin with moles, scars, or bruises or where the skin is tender, red, hard, or injured.
There may be other side effects of Andembry that are not listed here. Contact your health care provider if you think you are having a side effect of a medicine. In the U.S., you can report side effects to the FDA at www.fda.gov/medwatch or by calling 800-FDA-1088 (800-332-1088). In Canada, you can report side effects to Health Canada at www.health.gc.ca/medeffect or by calling 866-234-2345.
