Research team finds novel drug improves outcomes for patients with rare kidney disorder

Focal segmental glomerulosclerosis (FSGS) is a rare kidney disorder that affects children and adults, and can lead to kidney failure. New findings from a team led by the University of Minnesota Medical School show patients with FSGS who were treated with the medication sparsentan experienced improved kidney function—making it a potential new treatment option for the disorder.

The research, published today in the New England Journal of Medicine, suggests sparsentan may provide kidney protection by significantly reducing excess protein in urine—known as proteinuria, a proven indicator of kidney damage.

"FSGS is a frustrating disease for children to deal with and affects their quality of life," said Michelle Rheault, MD, professor at the U of M Medical School and pediatric nephrologist with M Health Fairview. "We're committed to offering our patients with kidney disease access to new treatments through our clinical trial options."

Clinically, reduction of proteinuria and delaying time to kidney failure are critically important for patients. FSGS patients in this study who were treated with sparsentan through two years of treatment had lower protein in their urine and were more likely to achieve complete remission compared to patients treated with irbesartan, the current standard treatment.

Although the endpoint for glomerular filtration rate—which measures how well kidneys filter blood—was not achieved after two years of treatment, other improvements were seen, including:

• Significant proteinuria reduction
• Higher rates of partial or complete remission
• Lower rates of reaching end-stage kidney disease

These findings suggest sparsentan could be a potential new treatment option for FSGS. Clinically, reduction of proteinuria and delaying time to kidney failure are critically important for patients.

Further analysis is ongoing to determine which patients with FSGS may benefit the most from sparsentan.

This research was funded by Travere Therapeutics—the maker of sparsentan.