Lundbeck receives orphan drug designation in the US and EU for Lu AG13909 for the treatment of congenital adrenal hyperplasia

• Congenital adrenal hyperplasia (CAH) is a rare autosomal recessive disease¹ with an estimated global incidence of approximately 1 in 14,000–18,000 live births²
• A phase II trial has recently been initiated to investigate the efficacy and safety of LuAG13909 for the potential treatment of CAH³

Valby, Denmark, 24 June 2025 – Lundbeck today announces that orphan drug designation has been granted to Lu AG13909 by the US Food and Drug Administration (FDA) on 12 May 2025 and the European Medicines Agency (EMA) on 20 June 2025. Lu AG13909 is a novel, humanised monoclonal antibody, under investigation for the treatment of patients with CAH, a rare genetic disease. CAH is characterised by impaired cortisol production and elevated levels of adrenocorticotropic hormone (ACTH), a hormone produced in the brain and involved in the regulation of multiple functions in the body. Elevated levels of ACTH lead to additional adrenal hormone imbalance, ultimately resulting in multiple developmental disturbances including symptoms related to the central nervous system, and long-term health concerns.

“CAH is a life-long condition, requiring constant management. Many existing treatments focus on controlling cortisol levels, however these options are often complicated by side effects. The orphan drug designation for Lu AG13909, our potential first in class anti-ACTH antibody, reflects the program’s innovative approach, as well as the high medical need to find new treatments for CAH” said Johan Luthman, EVP and Head of Research and Development at Lundbeck.

Lu AG13909 is advancing to mid-stage clinical development, as a new therapeutic approach for conditions marked by elevated ACTH levels, such as CAH. Lundbeck is currently expanding an ongoing Phase I/II clinical open-label trial, evaluating the efficacy and safety of anti-ACTH antibody Lu AG13909 in adults with classic CAH. The trial will open for enrolment in North America and seven countries across Europe, with the first sites opening in late June 2025.

The expanded trial will enrol men and women, aged ≥18 to ≤70 years with classic CAH, under stable glucocorticoid dosing. Participants will receive monthly intravenous administrations of Lu AG13909 and will be divided into two cohorts. The first will include participants with hyperandrogenemia, and the second will include participants with normal androgen levels, but treated with supraphysiologic glucocorticoid doses. Participants may enter an optional open-label extension, where they receive monthly Lu AG13909 administration over a period of 12 months.

About Lu AG13909
Lu AG13909 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 in the adrenal glands and thereby inhibits the neurohormonal signalling of ACTH. This inhibition causes a decreased secretion of glucocorticoids, mineralocorticoids and androgens from the adrenal glands.^3,4

ACTH plays a key role in the biosynthesis of adrenal steroids⁵ and is therefore considered a promising therapeutic target in conditions characterized by elevated ACTH levels.⁴ In this context, Lu AG13909, a novel molecule, may provide a therapeutic approach for treating conditions associated with chronically elevated ACTH levels.

In animal studies, Lu AG13909 has shown significant and durable reductions of corticosterone/cortisol and aldosterone.³ No adverse effects were observed after 6 months of intravenous dosing.

About congenital adrenal hyperplasia
Classic CAH is a rare, autosomal recessive disorder¹ affecting 1 in 14,000–18,000 live births worldwide.² Classic CAH is characterized by an enzyme deficiency, most commonly 21-hydroxylase deficiency, affecting the adrenal steroidogenesis leading to cortisol and aldosterone deficiency. People with 21-hydroxylase deficiency are at risk of adrenal crisis, a life-threatening condition contributing to the increased mortality throughout life.⁶ Balancing physiological glucocorticoid replacement and control of hyperandrogenism remains a challenge with the risk of long-term consequences of glucocorticoid overtreatment.^7-9