Changes in Adrenal and Gonadal Androgens After 14-Day Treatment With CRF1 Receptor Antagonist, Crinecerfont (NBI-74788), in Men With Classic 21-Hydroxylase Deficiency

Background: Congenital adrenal hyperplasia due to classic 21-hydroxylase deficiency (21OHD) causes cortisol insufficiency and androgen excess. A phase 2 trial of crinecerfont, a CRF1 receptor antagonist, in 18 adults with 21OHD showed prominent decreases in ACTH, 17-hydroxyprogesterone, and androstenedione (A4), and in women, testosterone (T), after 14 days of treatment. In men with 21OHD, T derives from both adrenals and testes; in poor disease control, A4/T ratio is elevated due to disproportionately increased adrenal A4 production and decreased testicular T production. We sought to determine the impact of crinecerfont on both adrenal and gonadal androgen production in men with 21OHD in this phase 2 trial. Methods: A4 and T data were analyzed for 7 men who completed 1 or more of 4 oral dosing regimens: Cohort 1, 50 mg QHS, n=4; Cohort 2, 100 mg QHS, n=2; Cohort 3, 100 mg QPM, n=5; and Cohort 4, 100 mg BID, n=3 (14 total treatment periods). Mean 0600-1000 4-hour morning window (M4hMW) and mean 24-hour (M24h) A4, T, and A4/T ratios were analyzed from serial serum samples at baseline and on day 15. Results: Dose-dependent reductions in M4hMW A4 were observed [median (range)] in men, consistent with previously presented data in all subjects:Cohort 1: -21% (-84 to -12%);Cohort 2: -37% (-51% to -23%);Cohort 3: -43% (-85% to +140%);Cohort 4: -62% (-90% to -33%). In contrast, M4hMW T showed inconsistent changes [median (range)]: Cohort 1: +18% (-40% to +82%);Cohort 2: -4% (-4.3% to -3.8%);Cohort 3: +9% (-11 to +24%);Cohort 4: +9% (-3% to +27%). Thus, M4hMW A4/T ratios decreased with dose. Values at baseline, on day 15, and percent changes [median (range)] were, respectively:Cohort 1: 0.9 (0.3–2.6), 0.6 (0.1–2.1), -26% (-91% to +23%);Cohort 2: 5.0 (4.8–5.2), 3.3 (2.5–4.2), -35% (-49% to -20%);Cohort 3: 0.6 (0.1–6.9), 0.3 (0.1–2.7), -54% (-85% to +178%);Cohort 4: 3.9 (0.6–5.9), 0.4 (0.3–2.1), -65% (-92% to -31%). M24h A4/T ratios similarly declined in all cohorts. Values at baseline, on day 15, and percent changes [median (range)] were, respectively:Cohort 1: 1.0 (0.3–2.3), 0.4 (0.1–1.9), -33% (-92% to +2%);Cohort 2: 4.3 (3.8–4.9), 2.7 (2.4–3.0), -36% (-51% to -22%);Cohort 3: 0.5 (0.1–4.7), 0.4 (0.1–2.4), -59% (-78% to +310%);Cohort 4: 3.2 (0.4–4.1), 0.4 (0.3–1.7), -58% (-89% to -31%). Conclusions: Following crinecerfont therapy, A4 and A4/T decreased in a dose-dependent manner in men with 21OHD. In contrast to reductions in T observed in women with 21OHD, T did not change consistently and rose in some men. Preserved T values despite marked A4 reductions suggests testicular T production increased during crinecerfont therapy, perhaps due to release of gonadotropin suppression from adrenal-derived androgens. Long term studies are needed to determine if crinecerfont treatment improves additional measures of testicular function in men with 21OHD. Reference: RJ Auchus, et al. J Endocr Soc 2020;4(Suppl 1):OR25-03.

OR25-03 The Effects of Crinecerfont (NBI-74788), a Novel CRF1 Receptor Antagonist, on Adrenal Androgens and Precursors in Patients with Classic Congenital Adrenal Hyperplasia: Results from A Multiple-Dose Phase 2 Study

Introduction: Classic congenital adrenal hyperplasia due to 21-hydroxylase deficiency (21OHD CAH) is a rare autosomal recessive disease that results in impaired cortisol synthesis and excess androgen production. Compounds that inhibit adrenocorticotropic hormone (ACTH) release could reduce adrenal androgen production and thus the amounts of exogenous glucocorticoids needed to decrease these androgen levels. This study evaluated the effect of crinecerfont (NBI-74788), a novel, non-steroidal, and selective corticotropin-releasing factor-1 (CRF1) receptor antagonist on adrenal androgens and precursors in adults with 21OHD CAH. Methods: This open-label, multiple-dose study enrolled men and women (18–50 years old) with 21OHD CAH. A sequential-cohort design evaluated 4 crinecerfont oral dosing regimens: 50 mg QHS (Cohort 1); 100 mg QHS (Cohort 2); 100 mg QD (Cohort 3); and 100 mg alternative dosing (Cohort 4). Each regimen was administered for 14 consecutive days. ACTH, 17-hydroxy-progesterone (17OHP), and androstenedione (A4) were measured serially over a 24-hour period, at baseline and after 14 days of dosing. Results: Analyses included 23 participants: Cohort 1 (4 women, 4 men: mean age 31.1 years); Cohort 2 (5 women, 2 men: mean age 32.9 years); and Cohort 3 (3 women, 5 men: mean age 30.9 years). Cohort 4 is ongoing. At baseline, median plasma ACTH, serum 17OHP, and serum A4 levels were as follows: Cohort 1 (ACTH, 151 pg/mL; 17OHP, 5352 ng/dL; A4, 270 ng/dL); Cohort 2 (ACTH, 232 pg/mL; 17OHP, 12821 ng/dL; A4, 597 ng/dL); and Cohort 3 (ACTH, 470 pg/mL; 17OHP, 6451 ng/dL; A4, 299 ng/dL). After 14 days of once-daily crinecerfont 50 mg, Cohort 1 patients had median percent reductions from baseline in plasma ACTH (-54%), serum 17OHP (-60%), and serum A4 (-21%). Median percent reductions were generally larger with 100 mg in Cohort 2 (ACTH, -67%; 17OHP, -75%; A4, -47%) and Cohort 3 (ACTH, -69%; 17OHP, -55%; A4, -43%), consistent with a dose-related response. Adverse events were mostly mild; no clinically significant findings from routine laboratory tests, vital signs, or electrocardiograms were noted. Conclusions: Results of this Phase 2 study of crinecerfont, a novel, orally administered, selective CRF1-receptor antagonist, indicated clinically meaningful reductions of elevated ACTH, 17OHP, and A4 in adults with 21OHD CAH after 14 days of treatment. Further studies are warranted to evaluate the effects of chronic crinecerfont therapy on maintenance of adrenal steroid production, clinical endpoints of disordered steroidogenesis, and reductions in GC exposure in both adult and pediatric patients with 21OHD CAH.