A Study of the Effect and Safety of Sparsentan in the Treatment of Patients With IgA Nephropathy

To join this study, you generally need to be at least 18 years old and have a confirmed diagnosis of IgA nephropathy (IgAN) through a kidney biopsy. Your urine should show a certain amount of protein, and your kidneys should have a specific level of filtering ability when you join. You should also already be taking stable doses of standard kidney-protective medicines like ACE inhibitors or ARBs, but your disease must still be considered at high risk of getting worse.

There are also reasons why you might not be able to join. For example, if your IgAN is caused by another condition, or if you have severe scarring in your kidneys from the biopsy. You also wouldn't be able to participate if you have certain other serious health issues like recent heart problems, very low blood count, high potassium levels, or problems with your liver. The study also cannot include individuals with a history of serious allergic reactions to similar medications or if you've had organ transplants (except for specific eye transplants).

Also, if you need to take certain immunosuppressive medications for more than a couple of weeks, or if your blood pressure is too high, you wouldn't be eligible. Women taking part would need to agree to use contraception. The study team will carefully review all your health information to make sure it's safe and appropriate for you to participate.

If you decide to take part in this study, you will first go through a screening process to check if you're suitable. Once enrolled, you'll be randomly assigned to receive either sparsentan or irbesartan, which you will take as a single tablet by mouth every morning. Neither you nor your doctor will know which medicine you are receiving during the main part of the study.

Throughout the study, you'll have regular visits to the clinic for assessments. These will include blood tests, urine tests (to measure protein levels), blood pressure checks, and discussions about your general health and any side effects you might experience. These visits are important for the researchers to monitor how the treatment is affecting you and your kidney function.

The main double-blind part of the study is expected to last for about 114 weeks (around two years). After this, if you meet certain criteria, you might have the option to continue in an 'open-label' extension period for up to an additional 156 weeks (about three years), where all participants will know they are receiving sparsentan. In total, your participation could last up to 270 weeks (around five years).