Wierman, Margaret E.

Abstract Context Crinecerfont, a first-in-class corticotropin-releasing factor type 1 receptor antagonist, is FDA-approved as an adjunct to the physiologic glucocorticoid (GC) required to treat the underlying adrenal insufficiency in patients (≥4 years old) with classic congenital adrenal hyperplasia (CAH). By reducing elevated adrenocorticotropic hormone, crinecerfont controls excess adrenal androgens, thereby enabling lower GC doses. However, there are no published recommendations for how to reduce supraphysiologic GC doses after initiating crinecerfont. This manuscript aims to provide a framework developed by experienced endocrinologists for reducing supraphysiologic GC doses in patients taking crinecerfont. Evidence Acquisition An experienced panel of 11 endocrinologists discussed strategies and considerations when reducing GC doses and developed an algorithm to guide GC dose reductions after introducing crinecerfont in adults with CAH. Evidence Synthesis Approaches to GC reduction should be individualized based on the patient's therapeutic goals, cortisol needs, lifestyle preferences, and the clinician's experience to set appropriate targets for clinical parameters, androgens, and GC dose regimen. In general, GC doses should be reduced gradually to minimize the risks of developing symptoms of GC withdrawal or adrenal insufficiency. GC doses should be adjusted to the lowest level needed to maintain androgens at goal, without reducing below what is needed for cortisol replacement. Practical considerations during GC dose reduction include switching from longer- to shorter-acting GCs (eg, from dexamethasone to hydrocortisone), optimizing dose distribution to mimic normal circadian cortisol exposure, and consolidating or eliminating doses to improve adherence. Conclusion This framework for reducing supraphysiologic GC doses in adult patients taking crinecerfont may become increasingly relevant as treatment of CAH shifts toward physiologic GC replacement with adjunctive control of adrenal androgens.

Single-cell diversity in the brain The cells that make up an organism may all start from one genome, but somatic mutations mean that somewhere along the line of development, an organism's individual cellular genomes diverge. McConnell et al. review the implications and causes of single-cell genomic diversity for brain function. Somatic mutations caused by mobile genetic elements or errors in DNA repair may underlie certain neuropsychiatric disorders. Science , this issue p. eaal1641