Neurocrine Biosciences has presented the first retrospective case series of CRENESSITY in patients with classic congenital adrenal hyperplasia due to 11β-hydroxylase deficiency.
The data were presented at ENDO 2026 and provide early real-world clinical insight into a rare CAH subtype that had not previously been studied in CRENESSITY clinical trials.
This is relevant because classic congenital adrenal hyperplasia is a lifelong rare genetic disorder that disrupts adrenal hormone production. While 21-hydroxylase deficiency is the most common form, 11β-hydroxylase deficiency represents a smaller and less-studied patient population with distinct clinical management needs.
The case series found that androstenedione and other adrenal hormone levels improved substantially after CRENESSITY initiation. Neurocrine reported more than 90 per cent median reductions in 11-deoxycortisol and 11-deoxycorticosterone.
Nearly all patients in the series, 14 out of 15, reduced their total glucocorticoid dose after treatment with CRENESSITY. Two of five patients who were receiving antihypertensive medications reduced or discontinued those drugs.
CRENESSITY, also known as crinecerfont, is designed to reduce excess ACTH-driven adrenal androgen production and help lower the need for supraphysiologic glucocorticoid dosing. This is clinically relevant because long-term glucocorticoid exposure can contribute to metabolic, growth and bone health complications.
The findings are early and retrospective, meaning they should be interpreted with caution. Larger prospective studies would be needed to confirm durability, safety and broader applicability in 11β-hydroxylase deficiency.
Adoption in this rare subtype will depend on physician awareness, insurance coverage, endocrine specialist access and confidence in extending use beyond the populations most represented in pivotal trials. The development reflects how post-approval evidence can help clarify treatment value in smaller rare disease subgroups that are often underrepresented in formal studies.
