Real-world outcomes with modified-release hydrocortisone in classic congenital adrenal hyperplasia

To evaluate outcomes after switching from conventional glucocorticoids (GCs) to modified-release hydrocortisone (MR-HC; Efmody) in adults with classic congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency under real-life conditions.

Prospective, observational cohort study at a tertiary endocrine center.

Sixty-two adults with classic CAH (25 male; 42 salt-wasting) were switched to MR-HC and followed up for at least 12 months and up to 4 visits or until termination of treatment (median 23.5 months; visit 4 not yet completed in 6/62). Outcomes included hormonal control, metabolic parameters, and menstrual patterns.

At baseline, 42/62 patients had androstenedione (A4) within the reference range, 13/62 showed elevated concentrations, and 7/62 had suppressed concentrations. At the last available visit, 11/13 of patients with elevated A4 normalized. Salivary 17-hydroxyprogesterone decreased significantly in the early morning (P = .025), 12 Pm (P = .036) and 4 Pm (P = .042). Median hydrocortisone-equivalent dose declined from 30 mg (IQR 25-37.5) to 25 mg (IQR 20-30) (P < .001). HOMA-IR improved (2.15-1.67; P = .023), while other metabolic parameters remained stable. Daytime blood systolic and diastolic pressure decreased by ∼5 mmHg (P = .007 and P = .003). Fludrocortisone was reduced in 12/41 (29.3%) salt-wasting patients. Among women with menstrual disturbances (12/42), 6/12 normalized and 1/12 conceived; among women with regular cycles, 3/12 developed irregular cycles or amenorrhea. The adrenal crisis rate was 5.0 per 100 patient-years.

MR-HC enabled stable biochemical control with reduced GC exposure and was associated with improvements in insulin sensitivity, blood pressure, and menstrual regularity, supporting its role as a safe and physiological treatment option in adults with CAH.