FDA Grants Orphan Drug Designation to Lundbeck's Anti-ACTH Antibody Asedebart for Endogenous Cushing's Syndrome
核心洞察
The U.S. FDA has granted Orphan Drug Designation to asedebart (搜索) (Lu AG13909), Lundbeck's investigational anti-ACTH monoclonal antibody, for endogenous Cushing's syndrome (搜索).
Asedebart (搜索) is a humanized antibody that blocks ACTH binding to the melanocortin 2 receptor (搜索), reducing adrenal secretion of glucocorticoids, mineralocorticoids and androgens.
Proof-of-concept trials are ongoing in Cushing's disease (搜索) and classic congenital adrenal hyperplasia (搜索), with orphan designations already secured in the EU, U.S. and Japan.
The U.S. Food and Drug Administration (搜索) has granted Orphan Drug Designation (ODD) to asedebart (搜索) (Lu AG13909), Lundbeck's novel investigational anti-ACTH monoclonal antibody, for the treatment of endogenous Cushing's syndrome (搜索), the Danish biopharmaceutical company announced on Sept. 11, 2026.
Endogenous Cushing's syndrome (搜索) encompasses both ACTH-dependent and ACTH-independent forms. The ACTH-dependent form is a rare, serious endocrine disorder caused by excess secretion of adrenocorticotropic hormone (ACTH), most commonly from a pituitary tumor (Cushing's disease (搜索)) and less frequently from an ectopic ACTH-secreting tumor. Elevated ACTH drives increased adrenal production of glucocorticoids, mineralocorticoids and androgens, disrupting normal physiological homeostasis.
Sustained cortisol excess is of particular importance, contributing to a considerable disease burden through metabolic, cardiovascular and neuropsychiatric complications, and is associated with increased morbidity and mortality. Although existing medical therapies can reduce or control elevated cortisol levels, important treatment gaps remain, and achieving and maintaining adequate disease control can be difficult, with available therapies differing in their efficacy and potentially constrained by safety and tolerability considerations.
Mechanism of Action and Development Program
Asedebart (搜索) is a humanized anti-ACTH monoclonal antibody that specifically recognizes ACTH with high affinity. It blocks the binding of ACTH to the melanocortin 2 receptor (搜索) in the adrenal glands, thereby inhibiting the neurohormonal signaling of ACTH. This inhibition reduces secretion of glucocorticoids, mineralocorticoids and androgens from the adrenal glands.
Because ACTH plays a key role in the biosynthesis of adrenal steroids, it is considered a promising therapeutic target in conditions characterized by elevated ACTH levels. Through its mechanism of action, asedebart (搜索) has the potential to treat conditions associated with chronically elevated ACTH, such as Cushing's disease (搜索) (CD) and classic congenital adrenal hyperplasia (搜索) (CAH).
The antibody is advancing in clinical development as a potential first-in-class treatment for rare conditions characterized by excess ACTH, with proof-of-concept trials ongoing in CD and classic CAH to evaluate efficacy and safety. A proof-of-concept trial evaluating the efficacy and safety of Lu AG13909 in Cushing's disease (搜索) is currently ongoing.
Regulatory Momentum Across ACTH-Driven Disorders
With the FDA designation, asedebart (搜索) continues to build momentum with regulatory authorities across rare ACTH-driven disorders. The antibody has also received orphan designation in the European Union for Cushing's syndrome of endogenous origin, in addition to previous orphan drug designations for CAH in the European Union and the United States, and for CAH and CD in Japan.
"The FDA Orphan Drug Designation is an important step for asedebart (搜索) and for Lundbeck's growing commitment to rare neuroendocrine disorders," said Tarek Samad, Executive Vice President and Head of Research & Development at Lundbeck. "ACTH-dependent Cushing's syndrome can be a devastating condition for patients, with long-term consequences that remain difficult to control despite available treatments. This milestone reflects the strength of the science behind asedebart's development to date and supports our ambition to advance innovative medicines in areas where patients continue to face significant unmet need."
Treatment Landscape and Unmet Need
Surgery to remove the source of excess ACTH is the preferred first-line treatment when feasible; however, not all patients are eligible for surgery or achieve sustained remission. Current medical therapies can help manage cortisol excess, but disease control remains challenging and treatment options may be limited by variable efficacy, safety and tolerability.
Orphan Drug Designation is granted by the FDA to drugs and biologics intended to treat, diagnose or prevent rare diseases or conditions. The designation may provide certain development incentives, including tax credits for qualified clinical testing, exemption from certain FDA application fees and, if approved, potential seven years of market exclusivity for the designated indication.
Lundbeck noted that asedebart (搜索) is an investigational compound that is not approved for marketing by any regulatory authority worldwide, and its efficacy and safety have not been established. The company is a biopharmaceutical company focusing exclusively on brain health, with more than 70 years of experience in neuroscience.