Recent Advances in Hereditary Angioedema

Written by Stephanie Booth
Medically Reviewed by Brunilda Nazario, MD on January 15, 2026
4 min read

Hereditary angioedema (HAE) is a rare condition that causes sudden and intense swelling attacks. They can affect parts of your body that you can see, like your hands, feet, or face. They can also happen inside your body, like in your gastrointestinal tract or your airway. 

HAE attacks can be scary and hard to predict. At times, they can also be life-threatening. There’s no cure for HAE, but doctors keep getting better at treating it, thanks to recent research advances.

“I feel very optimistic about the future of HAE treatment. The advances are transformative,” says Daniel Ganjian, MD, a pediatrician at Providence Saint John’s Health Center in Santa Monica, California. 

 

HAE symptoms usually start before the age of 13, but it can take up to a decade for some people to get diagnosed. That’s in part because this condition is so rare. Only 1 to 2 people per 100,000 have hereditary angioedema.

“Too often, patients believe their symptoms are common allergies, which can delay them from getting the right care,” says Ganjian.

Allergy medications can’t treat HAE because the swelling it causes isn’t an allergic reaction. It most commonly happens because of a genetic disorder. Your body doesn’t make enough of a specific protein, called C1-INH, which helps control inflammation. 

“A key breakthrough in understanding [hereditary angioedema] has involved precisely mapping the kallikrein-kinin system,” says Ganjian. Also known as KKS, this network plays a key role in inflammation. 

Researchers now know that when you don’t have enough C1-INH, you end up with too much of a peptide called bradykinin, which is made by the kallikrein enzyme. Bradykinin triggers inflammation in your body, and increases how much fluid leaks out of your blood vessels and into the soft tissue around it. That causes a swelling attack.

 

Sixty years ago, doctors didn’t have many ways to treat hereditary angioedema. Today, 12 FDA-approved hereditary angioedema treatments are available.  

Doctors can treat HAE with: 

On-demand (acute) medications

Some medications, like ecallantide (Kalbitor) and sebetralstat (Ekterly), can reduce how severe an HAE attack is and how long it lasts. You need to take this type of treatment as soon as you start to have symptoms.  Some of these medications can even be kept on hand at home or school, which has been another breakthrough in treating HAE. 

Preventative (prophylactic) medications 

Other drugs such as berotralstat (Orladeyo), donidalorsen (Dawnzera), and plasma-derived C1 esterase inhibitor (human) (Haegarda), try to keep an HAE attack from starting. Sometimes, these are used as long-term treatments.

Thanks to what researchers have learned about the causes of hereditary angioedema, today’s  treatments not only work better but cause fewer side effects than previous options.

Researchers keep trying to better understand HAE and develop even more options to stop swelling attacks. In the future, you’ll likely see:

More treatments for young kids. Right now, no treatments that are approved for kids under the age of 12 come in a pill form. Instead, they need to be given by a shot under the skin or through an IV. New medicines that can be swallowed and are easier for young kids to take are in clinical trials. 

Faster-acting treatments. For instance, deucrictibant is one new HAE on-demand treatment researchers are testing. It works by blocking the pathway that bradykinin uses to trigger swelling. In a clinical trial, people who took deucrictibant saw their HAE attacks stop getting worse in 20 minutes compared to nearly four hours for people who took a placebo. 

The median time to major symptom relief with deucrictibant was under three hours, compared to over 12 hours for people who were given a placebo.

Longer-acting treatments. In August 2025, donidalorsen (Dawnzera) was approved by the FDA for adults and kids over 12. It became the first RNA-targeted medicine for HAE, which means it works by binding to your body’s genetic material.  Donidalorsen helps block your body from making bradykinin. Because it’s a preventative treatment, you give yourself a shot every four to eight weeks.

More long-acting treatment options are also in development. “The clinical trials for very long-acting prophylactic treatments are quite exciting,” says Ganjian. “Imagine needing an injection only once a month or less — that level of freedom is a massive leap forward.”

Gene editing. This type of treatment involves changing your genes. Its goal is to correct the mutation (change) that causes a genetic disorder like hereditary angioedema.

In early clinical trials, gene editing shows promise in treating HAE. In one study, 10 participants received a one-time treatment of a gene therapy called lonvoguran ziclumeran (lonvo-z). After nearly three years of follow-up, 98% of participants still hadn’t had another HAE attack.  

Hereditary angioedema research has come a long way, but the progress that researchers have made in understanding this condition and finding new treatments isn’t over.

“The research community is highly energized, and I receive the impression that more breakthrough options are coming soon,” says Ganjian.