The Food and Drug Administration (FDA) has granted Fast Track designation to BBP-631, an investigational adeno-associated virus 5 (AAV5) gene therapy, for the treatment of congenital adrenal hyperplasia.

Congenital adrenal hyperplasia (CAH) is a group of rare inherited autosomal recessive disorders caused by gene mutations encoding the enzyme, 21-hydroxylase, which results in a lack of endogenous cortisol and aldosterone production. BBP-631 is designed to deliver a functional copy of the 21-hydroxylase gene to restore the body’s ability to produce cortisol and aldosterone.

The Company will initiate a first-in-human, open-label, dose escalation, phase 1/2 trial ( NCT04783181) to evaluate the safety, tolerability, and efficacy of a single intravenous administration of BBP-631 in adult participants with CAH. The trial will enroll approximately 25 participants. Initial data are anticipated in late 2021 or early 2022.

“The standard-of-care for CAH patients has not changed significantly over the last 50 years, and a gene therapy offers for the first time the possibility that patients may be able to make their own cortisol and aldosterone, at the right times and in the right amounts,” said Eric David, MD, JD, CEO at BridgeBio Gene Therapy. “The FDA’s Fast Track designation reinforces the urgency to address the unmet needs of patients with CAH as quickly and safely as possible.”

The FDA’s Fast Track designation allows for expedited review of therapies that are meant to treat serious or life-threatening conditions. Generally, the designation is granted to therapies that are expected to have an impact on factors such as survival and daily functioning.


BridgeBio Pharma receives FDA Fast Track designation for investigational gene therapy for congenital adrenal hyperplasia. [press release]. Palo Alto, CA: BridgeBio Pharma, Inc.; May 14, 2021.