The Evaluation of the Drug R3R01 for the Excretion of Protein in the Urine in Patients With Diabetic Kidney Disease.

The goal of this clinical trial is to to investigate whether the drug R3R01 has a beneficial effect on the amount of protein excreted in the urine in adult patients (above 18 years of age) with type 2 diabetes and resulting kidney disease. The main questions it aims to answer are: 1. Does 3 months of treatment with 200mg of the drug R3R01 morning and evening have a beneficial effect on the amount of protein excreted in the urine in patients with type 2 diabetes and kidney disease? 2. Does R3R01 have an effect on kidney function and daily blood pressure? Researchers will compare the results of 40 people who take R3R01 to 20 people who receive an inactive substance (placebo). Participants will receive R3R01 or the placebo as an oral tablet and undergo a selection of medical examinations - such as: * blood samples * urine tests * kidney tests involving a radiolabelled marker which is injected into the bloodstream and monitored via blood samples * 24 hour blood pressure monitoring via a wearable device * urine pregnancy test (if applicable)