The European Commission has granted orphan designation to asedebart (Lu AG13909), Lundbeck's investigational anti-ACTH monoclonal antibody, for endogenous Cushing's syndrome. The designation covers ACTH-dependent and ACTH-independent forms of the rare endocrine disorder, in which chronic cortisol excess can cause metabolic, cardiovascular and neuropsychiatric complications and increase morbidity and mortality. Asedebart is being developed for ACTH-dependent disease, including Cushing's disease (CD), and is designed to bind ACTH and block its interaction with the melanocortin 2 receptor in the adrenal glands. Proof-of-concept trials are ongoing in CD and classic congenital adrenal hyperplasia (CAH) to assess efficacy and safety. The European Union designation can provide protocol assistance, fee reductions and, if the medicine is approved, 10 years of market exclusivity for the designated indication. Asedebart is not approved for marketing by any regulatory authority, and its efficacy and safety have not been established.