This study is testing a new medicine called R3R01, which could help people with certain kidney problems. Alport Syndrome is when kidneys are damaged due to a genetic issue, and Focal Segmental Glomerulosclerosis (FSGS) is when parts of the kidney stop working properly. The study will test if R3R01 is safe, how well it works, and how it behaves in the body. People with uncontrolled proteinuria (too much protein in urine) while on ACE/ARB medicines can join. Participants will take R3R01 for 12 weeks. The study measures how much protein in urine changes after treatment.

• The study lasts 12 weeks, and you'll take R3R01 during this time.
• Participants must be at least 12 years old, with different age rules depending on the country.
• You must not have uncontrolled diabetes, certain infections, or other health issues.

To join, you must understand the study, agree to its terms, and sign a consent form. If you are a child, a parent or guardian must also agree. Women who can become pregnant and men with partners who can become pregnant must agree to use birth control during the study. If you have had COVID-19, certain conditions must be met before joining. This study will help learn more about R3R01's effects on kidney health.