This study looks at a new medicine to help kidneys in people who have protein in their urine due to either diabetic kidney disease or two other diseases that specifically impact the kidneys, called focal segmental glomerulosclerosis and treatment resistant minimal change disease. It looks at the safety of a new medicine, GFB-887, which blocks a channel called TRPC-5. Existing studies suggest that blocking the TRPC-5 channel can help lower urine protein levels and preserve kidney function in people with these diseases. The drug is a tablet taken once a day; depending on your doseage level, you may take up to 4 tablets once a day. Some participants will get the medications while others will get a placebo (also in tablet form); this will be decided randomly by chance. We will look at protein loss in the urine as the main outcome and also look at safety and kidney function.
- Age 18 or older
- Diagnosis of Diabetic Nephropathy, Focal Segemental Glomerularsclerosis (FSGS), or Treatment-Resistant Minimal Change Disease
- Protein in the urine (for diabetic nephropathy patients, urine albumin to creatinine ratio ≥150 mg/g; for FSGS and T-RMCD patients, urine protein to creatinine ration ≥1.0 g/g)
- Uncontrolled blood pressure (systolic blood pressure >160 mmHg or diastolic blood pressure >90 mmHg)
- Pregnant or breastfeeding
- Alanine aminotransferase (ALT) and/or aspartate aminotransferase (AST) >2 × upper normal limit, or a known history of severe or chronic hepatobiliary disease.
The study lasts about 26 weeks, including up to 6 weeks without the drug where we screen and take some initial data on you, 12 weeks where participants take a pill or pills daily, and another 8 weeks without the drug for follow-up. In the first few weeks, there is a visit weekly, but these are less frequent as the study goes on, spacing out to 4 weeks at the end. Twice during this study, you will be asked to capture your urine output at home for 24 hours.
There are no x-rays or scans but everyone will have an electrocardiogram (EKG).
There are frequent urine samples and blood draws, up to a few tablespoons per visit.
Some visits will be about an hour, but 2 visits require you to stay in the hospital to take a few blood samples over the course of 8 hours (not overnight).