New Treatments for Hereditary Angioedema

Over the years, medical research has helped improve treatments for a variety of disorders, including one rare inherited blood disorder named hereditary angioedema.

Today, we cover what this disorder is and how research has helped to improve the treatments available to people with this condition.

What Is Hereditary Angioedema?

Hereditary angioedema is a very rare genetic condition that can prove life threatening, especially when not diagnosed or monitored. The disorder affects between 1 in 10,000 and 1 in 50,000 people, and can affect individuals with varying degrees of severity.

There are three types of hereditary angioedema. The variations in types I, II and III are based on what gene mutation causes the condition, as well as the levels of the C1 inhibitor protein present in the patients’ blood. While these three types are diagnosed differently, and may be treated differently, the symptoms and effects on the patient remain similar. Type I is by far the most common, occurring in 85 out of every 100 cases (source).

As an inherited disorder, the patient may have received one copy of the mutated gene from one of his or her two parents. However, the mutation can also occur spontaneously, not requiring the parent to have carried the gene or have ever been diagnosed.

Symptoms of hereditary angioedema attacks can include the following:

• Edema, or swelling, of the hands, feet, intestines, limbs, face, airway, recurring in episodes
• Abdominal pain
• Nausea
• Vomiting

These attacks can be triggered by stress or an injury, surgery, or other bodily trauma, but they can also occur with no discernible cause. Recurring episodes may last 2-4 days and may affect only one or multiple areas of the body at the same time. Hereditary angioedema is most dangerous when swelling affects the throat and vocal box, as that swelling can inhibit breathing and cut off necessary airways.

Ever had a bee sting or bug bite? You might have swelled at the site of the sting, and used an antihistamine or epinephrine to help the swelling go down. Unfortunately, hereditary angioedema cannot be treated through the use of those medications, as they have proven to be ineffective.

Hereditary Angioedema Treatments

For many years, a variety of treatments were used to lessen the impact of hereditary angioedema, however, they were met with limited success. Patients underwent surgeries, took steroids and used anti-inflammatories, however, none were able to affect the root cause and all came with unpleasant and often irreversible side effects.

Today, medical research has led to new options to treat patients who are experiencing an attack. Between 2008 and 2009, two intraveneous C1 inhibitors were approved by the FDA, boosting the C1 inhibitor activity lacking in hereditary angioedema patients. The first injected HAW medicine was approved in 2009, as well, followed by a self-administered injection to prevent fluid build-up in 2011.

Each of these treatments have allowed hereditary angioedema patients to quickly be treated during an attack. Further medical research is being done, both to treat symptoms and attacks, as well as to find a cure for the disorder. Research gets us closer every day to establishing treatments that can provide permanent relief to these patients.