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For individuals living with classic congenital adrenal hyperplasia (CAH), the standard of care has long presented a difficult dilemma. While patients require glucocorticoids (GCs) to survive, the historical reliance on supraphysiologic doses—doses higher than what the body naturally produces—has carried a heavy burden of long-term health risks, including metabolic complications, bone density loss, and mental health challenges. Recently, Neurocrine Biosciences announced promising new two-year data that could fundamentally shift how this condition is managed.
Significant Progress in Reducing Glucocorticoid Exposure
At the American Association of Clinical Endocrinology 2026 Annual Meeting, researchers presented findings from the Phase 3 CAHtalyst® Adult study. The data highlights the effectiveness of CRENESSITY® (crinecerfont) in helping patients reach and maintain physiological-range glucocorticoid dosing. Specifically, at the two-year mark, approximately 70% of participants achieved a physiologic GC dose, successfully lowering their reliance on the high-dose regimens that have historically defined CAH treatment.
Perhaps most notably, this reduction did not come at the cost of hormone control. Patients were able to lower their GC intake while simultaneously maintaining control over adrenal androgens. For those previously taking potent medications like dexamethasone, the results were particularly impactful: 75% of patients transitioned off dexamethasone entirely, allowing for a more natural approach to cortisol replacement.
Improving Long-Term Health Outcomes
The implications for patient quality of life are substantial. Dr. Richard J. Auchus, Principal Investigator for the CAHtalyst Adult study, emphasized that the, “sequelae significantly impact quality of life and commonly develop with traditional CAH treatment regimens.” By providing a way to safely reduce cumulative steroid exposure, CRENESSITY offers a potential solution to mitigating the risks of obesity, diabetes, and cardiovascular issues that have plagued the CAH patient community for decades.
Key study metrics from the two-year mark include:
- 69% of patients reached the physiologic GC dose threshold of hydrocortisone equivalents.
- Sustained efficacy: The mean percent change from baseline in GC dose remained stable at -38% from month 18 through month 24.
- High retention: Over 80% of study participants remained in the trial, suggesting the treatment is well-tolerated over the long term.
A New Era for CAH Care
As the largest interventional trial conducted to date in the classic CAH population, these findings provide clinical evidence that durability is possible with CRENESSITY. By acting as a corticotropin-releasing factor type 1 receptor (CRF1) antagonist, the treatment addresses the underlying hormonal drivers of the condition without requiring the massive doses of steroids previously needed to suppress ACTH production.
For clinicians and patients alike, this milestone represents a move away from the traditional, often damaging reliance on high-dose steroids. With these two-year results, there is a clear path forward for managing classic CAH in a way that prioritizes both hormonal balance and long-term systemic health.