BBP-631

BBP-631 is an investigational gene therapy developed by BridgeBio Pharma for the treatment of congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency. It utilizes an adeno-associated virus serotype 5 (AAV5) vector to deliver a functional copy of the CYP21A2 gene, which encodes the 21-hydroxylase enzyme, directly to the adrenal gland. The goal is to restore endogenous cortisol and aldosterone production in patients with CAH, potentially reducing or eliminating their need for lifelong glucocorticoid or mineralocorticoid replacement therapy. Preclinical studies demonstrated efficient and persistent delivery of the therapeutic gene, and early clinical data showed increased endogenous cortisol production in treated patients. Despite these advances, development was discontinued after Phase 1/2 trials due to strategic business decisions rather than safety concerns[1][3][4][5][7].