A Study to Learn About How Well BAY 3401016 Works in Adults With Alport Syndrome

A Randomized, Double-blind, Placebo-controlled, Parallel Group Phase 2a Study With an Extension Phase to Evaluate the Efficacy and Safety of BAY 3401016 in Participants Aged 18 to 45 With Alport Syndrome

Alport syndrome (AS) is a rare genetic condition that causes kidney disease, hearing loss, and eye abnormalities that occur due to changes in specific genes (COL4A3, COL4A4, and COL4A5). These genes help in producing an important protein called collagen. People with AS have a high risk of developing chronic kidney disease (CKD), a condition in which there is progressive loss in kidney function over time. The kidneys soon lose their ability to remove waste products from the body properly, resulting in end-stage kidney disease. A common sign of decreasing kidney function is the presence of excess protein in the urine that is not usually found with healthy kidneys. This condition is known as proteinuria. The study drug, BAY 3401016 (a monoclonal antibody), is a type of medicine that blocks a protein called Semaphorin 3A (Sema3A), which is thought to be involved in causing kidney damage in AS. By blocking the action of the Sema3A protein, BAY 3401016 may prevent proteinuria and slow down the loss in kidney function due to AS.

The main purpose of this study is to learn more about how well BAY 3401016 works in slowing down the loss in kidney function in adults with a rapidly progressing AS.

Inclusion Criteria:

• Participants must be 18 to 45 years of age inclusive
• Participants with AS, either XLAS (male) or ARAS (male or female)
• eGFR ≥ 45 mL/min/1.73m2
• UACR ≥ 500mg/g

Exclusion Criteria:

• Chronic kidney disease is different from AS
• Clinically significant illness that could have influence on the safety of the participant and/or interfere with the study objectives
• History or current existence of malignancy
• Participants with history of severe allergies, multiple drug allergies or non-allergic drug reactions including allergies affecting the lower respiratory tract - allergic asthma, allergies requiring therapy with corticosteroids or urticaria
• Participants with active skin disorders (e.g. atopic dermatitis, severe acne), that, in the investigator's judgment, could interfere with or confound the evaluation of local infusion/injection-site reactions to the study intervention.
• Systolic blood pressure above 140 mmHg
• Diastolic blood pressure above 90 mmHg