Crenessity is part of the CRF1 Antagonists class and treats Congenital Adrenal Hyperplasia. CRF1 antagonists, also known as corticotropin-releasing factor type 1 receptor antagonists, are used to treat congenital adrenal hyperplasia. They work by reducting the amount of corticotropic hormone levels which in turn can reduct the amount of steroid treatment a patient needs to take. Crenessity is only available as a brand name drug.