On October 22, 2020, BioCryst Pharmaceuticals, Inc. (“BioCryst”) announced the publication of data from a Phase 3 clinical trial evaluating berotralstat for patients with hereditary angioedema (HAE). As a developer of small-molecule therapies designed to treat patients with rare diseases, BioCryst wanted to improve quality of life (QOL) for patients with HAE. The data, published in the Journal of Allergy and Clinical Immunology, shares data collected during the first 24 weeks (5.5 months) of the trial.

Berotralstat

In the Phase 3 APeX-2 clinical trial, researchers evaluated the safety, efficacy, and tolerability of berotralstat. The therapy is orally-administered. 121 patients (ages 12+) enrolled in the trial. During the first portion of the trial, patients received either 110 or 150 mg berotralstat or a placebo. Ultimately, researchers determined that berotralstat significantly reduced HAE attacks and swelling, particularly in the higher dosage.

Currently, berotralstat is being considered in multiple countries under the name ORLADEYO. In the United States, BioCryst submitted a New Drug Application (NDA) for berotralstat, and is expecting a decision by the end of the year. It is also being considered in Japan, with a decision meant for the end of the year. In the European Union, the EMA approved a Marketing Authorization Application (MAA) for berotralstat, and will receive an opinion within the next year.

Hereditary Angioedema (HAE)

When you break down “hereditary angioedema,” you see that it is pretty aptly named. The condition is inherited through an autosomal dominant pattern, so someone only needs to inherit one defective gene from parents. “Angio” means it relates to blood vessels, and “edema” is swelling caused by excess fluid.

In HAE, the gene that normally controls a blood protein (C1-inhibitor) is either partially functional or non-functional. Normally, C1-inhibitor helps fight diseases and prevent inflammation. But without having enough working C1-inhibitor, a protein peptide called bradykinin begins to accumulate. Ultimately, this causes blood vessels to leak fluid into bodily tissue, causing inflammation.

HAE attacks can be caused by triggers, such as stress or injury, but swelling can still occur without any triggers. Generally, females with HAE have more attacks than males, which is believed to be caused by hormonal changes. Swelling commonly occurs in the arms, legs, hands, and toes; stomach and intestines; lips, eyelids, and cheeks; and the throat. As a result, patients may experience nausea and vomiting, abdominal pain, and difficulty breathing.

 People who have hereditary angioedema (also referred to as HAE or HAE disease) have a genetic defect on chromosome 11 that results in recurring attacks of unexplained, severe swelling underneath the skin. Hereditary angioedema affects an estimated 1 in 50,000 people.

Learn more about HAE here.