Study of Lu AG13909 in Participants With Congenital Adrenal Hyperplasia

Study Overview
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Brief Summary
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This study will evaluate the effects of different doses of Lu AG13909 in adult participants with congenital adrenal hyperplasia, also called CAH. CAH is a rare genetic disorder that affects a person's ability to produce certain hormones. The main goals of this study are to learn about the safety and tolerability of Lu AG13909, how Lu AG13909 behaves in the body, and how the body responds to Lu AG13909.

Official Title
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A Multi-site, Open-label, Sequential-group, Multiple-ascending-dose Study to Investigate the Safety, Tolerability, Pharmacokinetics, and Pharmacodynamic Effects of Lu AG13909 in Patients With Congenital Adrenal Hyperplasia

Conditions
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Congenital Adrenal Hyperplasia

Intervention / Treatment
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* Drug: Lu AG13909


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Confirmed diagnosis of 21-hydroxylase deficiency CAH (based on a pathogenic CYP21A2 variant and/or elevated 17-OHP). Morning (pre-glucocorticoid [GC] replacement dose) blood concentrations of 17-OHP >4-times upper limit of normal (ULN). Body mass index (BMI) ≥18.5 kilograms (kg)/square meter (m^2) (minimum 50 kg) and ≤35 kg/m^2. Stable GC replacement therapy for ≥1 month prior to the Screening Visit. For the salt-wasting form of CAH, the participant must have been on a stable dose of mineralocorticoid replacement for ≥3 months prior to the Screening Visit. Apart from CAH, the participant is generally healthy in the opinion of the investigator and based on medical history, physical examination, vital signs, ECGs, and the results of the safety laboratory tests. Exclusion Criteria: The participant is pregnant or breastfeeding. The participant has a clinically significant abnormal laboratory value, electrocardiogram (ECG) parameter, or vital signs value, or other safety findings at the Screening Visit that indicate a potential risk for the participant if enrolled, in the opinion of the investigator. The participant has a history of known hypersensitivity or intolerance to Lu AG13909 or its excipients. Other inclusion and exclusion criteria may apply.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 55 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Sequential Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Lu AG13909<br>Participants in Part A will receive multiple intravenous (IV) doses of Lu AG13909 per a prespecified dosing schedule. After data from Part A has shown that a pharmacologically relevant dose level is safe and tolerable, participants in Part B will then receive multiple IV doses of Lu AG13909 per a prespecified dosing schedule. | Drug: Lu AG13909<br>* Solution for infusion<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of Participants With Treatment-Emergent Adverse Events (TEAEs) |  | Up to Day 161 | 
| Number of Participants With Anti-Drug Antibodies (ADAs) |  | Day 1 up to end of study (Day 161) | 
| Cmax: Maximum Observed Serum Concentration of Lu AG13909 |  | 0 (predose) up to 24 hours postdose on Day 1 to Day 161 | 
| Tmax: Nominal Time Corresponding to the Occurrence of Cmax |  | 0 (predose) up to 24 hours postdose on Day 1 to Day 161 | 
| Ctrough: Minimum Observed Serum Concentration of Lu AG13909 |  | 0 (predose) up to 24 hours postdose on Day 1 to Day 161 | 
| t½: Apparent Elimination Half-life of Lu AG13909 |  | 0 (predose) up to 24 hours postdose on Day 1 to Day 161 | 
| AUC0-infinity: Area under the plasma concentration curve of x from zero to infinity of Lu AG13909 |  | 0 (predose) up to 24 hours postdose on Day 1 to Day 161 | 
| CL: Apparent Total Serum Clearance of Lu AG13909 |  | 0 (predose) up to 24 hours postdose on Day 1 to Day 161 | 
| Vz: Volume of Distribution During the Terminal Elimination Phase After IV Administration of Lu AG13909 |  | 0 (predose) up to 24 hours postdose on Day 1 to Day 161 | 
| Change From Baseline After Each Dose of Lu AG13909 in Blood Concentrations of 17-hydroxyprogesterone (17-OHP) and Androstenedione (A4) |  | Baseline up to Day 85 | 
| AUC0-tau: Area under the curve over a dosing interval |  | 0 (predose) up to 24 hours postdose on Day 1 to Day 161 |