Spruce Biosciences Inc. presented data from its Phase 2 clinical trial of tildacerfont in adults with classic congenital adrenal hyperplasia (CAH) at the European Society of Endocrinology’s 23rd European Congress of Endocrinology (ECE 2021).

SPR001-202 was an open-label, 12-week Phase 2a clinical trial, which assessed the ability of a daily dose of 400mg of tildacerfont to lower disease-driving hormones such as adrenocorticotropic hormone (ACTH), 17-hydroxyprogesterone (17-OHP), and androstenedione (A4) over a 12-week dosing period. These hormones are used by physicians as a means of measuring the severity of CAH. 

Patients with poor disease control upon study entry had mean baseline levels of ACTH, 17-OHP and A4 that were significantly above the upper limit of normal. Administration of tildacerfont to these patients resulted in mean maximum reductions of 84% in ACTH, 80% in 17-OHP, and 79% in A4 compared to baseline across the study period. This enabled reduction in the levels of these key hormones to normal or near normal levels, including normalization of ACTH levels in 60% and normalization of A4 levels in 40% of poor disease control patients during month three. 

Normalization of these highly elevated hormones in classic CAH patients without increases to daily steroid doses has not been reported to date with any other investigational product candidate. 

“It is encouraging to see that tildacerfont, an oral, once-daily, and non-steroidal investigational therapy, produced meaningful reductions in highly elevated hormone levels for classic CAH patients, including, in some cases, normalization of these hormone levels over twelve weeks,” said Richard Auchus, MD, PhD, the study’s lead investigator and Professor of Internal Medicine and Pharmacology, University of Michigan, Ann Arbor. “The data suggest that tildacerfont has the potential to improve the adverse consequences of androgen excess and to reduce the burden of daily glucocorticoid dosing for these patients.”