Neurocrine Biosciences Inc. (NASDAQ: NBIX) reported two-year data from its Phase 3 CAHtalyst Pediatric study showing sustained hormone control and clinical improvements in children and adolescents with classic congenital adrenal hyperplasia treated with CRENESSITY (crinecerfont).

The analysis included 86 participants aged four to 17 years who completed up to two years of treatment. At 24 months, patients showed mean reductions of 157 pg/mL in adrenocorticotropic hormone levels and 1,924 ng/dL in 17-hydroxyprogesterone levels compared to baseline, while maintaining reduced glucocorticoid doses averaging 3.2 mg/m²/day lower than baseline.

Among participants with obesity at baseline, 60% achieved clinically meaningful improvements in body mass index standard deviation scores at two years, with 23% reaching a BMI below the 85th percentile. Among those with insulin resistance at baseline, 61% no longer met insulin resistance criteria after two years of treatment.

The study also showed improvements in androgen-related outcomes. In patients with acne at baseline, mean severity scores decreased by 11.0 mm on a visual analog scale at 24 months. Among male participants with elevated androstenedione-to-testosterone ratios at baseline, 36% achieved normal ratios by month 24.

"These two-year findings showed that CRENESSITY achieved durable reductions in both androgen levels and glucocorticoid doses in children and adolescents with classic congenital adrenal hyperplasia," said Sanjay Keswani, chief medical officer at Neurocrine Biosciences.

Treatment was generally well tolerated with more than 80% study retention at two years and no new safety signals observed. The data was presented at the Pediatric Endocrine Society 2026 Annual Meeting in San Francisco.

CRENESSITY received FDA approval in December 2024 for treating classic congenital adrenal hyperplasia in adults and children four years and older. The open-label extension portions of both pediatric and adult studies are ongoing.