Interim Analysis of the Phase 3 PROTECT Study of FILSPARI™ (Sparsentan) in IgA Nephropathy Presented by Travere Therapeutics at NKF Spring Clinical Meetings

(April 12, 2023, New York, NY) — The National Kidney Foundation (NKF) will feature a late-breaking plenary session by Travere Therapeutics on the interim analysis of efficacy and safety data from the ongoing Phase 3 PROTECT Study evaluating FILSPARI™ (sparsentan) in adults with IgA nephropathy (IgAN). “Rapid and Sustained Proteinuria Reduction with Sparsentan in Immunoglobulin A Nephropathy (IgAN): PROTECT Study Interim Results” will be presented Wednesday, April 12, at 5:15 CT, at the NKF Spring Clinical Meetings, the largest multidisciplinary gathering of kidney care professionals in North America, taking place in Austin, TX, from April 11-15.

IgAN is a rare kidney disease (RKD) affecting up to 150,000 people in the U.S.,

and a leading cause of kidney failure due to glomerular disease.

“The data demonstrate the significant and clinically meaningful anti-proteinuric effect of sparsentan compared to irbesartan,” said Brad Rovin, M.D., Medical Director at Ohio State University Center for Clinical Research Management, Director of the Division for Nephrology, and steering committee member for the PROTECT Study. “The data also highlight a consistent treatment effect across patient populations, regardless of age, race, gender, clinical characteristics, and concomitant medications.”

Highlights of the interim results from the PROTECT Study, the largest interventional trial testing a novel molecule versus an active comparator in IgA nephropathy to date, include:

  • After 36 weeks of treatment, patients receiving FILSPARI (sparsentan) achieved a mean reduction in proteinuria from baseline of 49.8%, compared to a mean reduction in proteinuria from baseline of 15.1% for irbesartan-treated patients (p<0.0001).
  • Proteinuria reduction with FILSPARI was consistent across age groups, sex, race, ethnicity, and baseline strata of proteinuria and eGFR​.
  • During the double-blind treatment period, a significantly greater proportion of patients on FILSPARI achieved complete remission (urine protein excretion <0.3 g/day) and partial remission (urine protein excretion <1.0 g/day) of proteinuria compared to patients on irbesartan. Complete remission at any time over the course of the double-blind treatment period occurred in 20.8% of participants in the FILSPARI group and 7.9% of participants in the irbesartan group (p=0.0005). 70.3% of participants in the FILSPARI group achieved partial remission, compared to 44.1% of participants in the irbesartan group (p<0.0001).

Results from the interim assessment in the PROTECT Study also show that FILSPARI was well tolerated with a clearly defined safety profile that has been consistent across all clinical trials conducted to date with treatment-emergent adverse events (TEAEs) comparable to irbesartan. No cases of severe edema, heart failure, hepatotoxicity, or edema-related discontinuations were reported in the study as of the cutoff date. Body weight and blood pressure changes from baseline were not different between the FILSPARI and irbesartan groups.


Data from the study were recently published in The Lancet and announced by Travere Therapeutics.


Thousands of kidney care professionals will attend the Spring Clinical Meetings in-person and virtually. Hundreds of the latest studies and kidney care advances will be unveiled.


About IgA Nephropathy

IgA nephropathy (IgAN), also called Berger's disease, is a rare kidney disease (RKD) characterized by the buildup of immunoglobulin A (IgA), a protein that helps the body fight infections, in the kidneys. The deposits of IgA cause a breakdown of the normal filtering mechanisms in the kidney, leading to hematuria, proteinuria, and a progressive loss of kidney function. Other symptoms of IgAN may include edema and high blood pressure. IgAN is the most common type of primary glomerulonephritis worldwide and a leading cause of kidney failure due to glomerular disease.

NKF Spring Clinical Meetings

For the past 31 years, nephrology healthcare professionals from across the country have come to NKF’s Spring Clinical Meetings to learn about the newest developments related to all aspects of nephrology practice; network with colleagues; and present their research findings. The NKF Spring Clinical Meetings are designed for meaningful change in the multidisciplinary healthcare teams’ skills, performance, and patient health outcomes. It is the only conference of its kind that focuses on translating science into practice for the entire healthcare team. 

About Kidney Disease

In the United States, more than 37 million adults are estimated to have kidney disease, also known as chronic kidney disease (CKD)—and approximately 90 percent don’t know they have it. About 1 in 3 adults in the U.S. are at risk for kidney disease. Risk factors for kidney disease include: diabeteshigh blood pressureheart diseaseobesity, and family history. People of Black or African American, Hispanic or Latino, American Indian or Alaska Native, Asian American, or Native Hawaiian or Other Pacific Islander descent are at increased risk for developing the disease. Black or African American people are about four times as likely as White people to have kidney failure. Hispanics experience kidney failure at about double the rate of White people.

NKF Professional Membership

Healthcare professionals can join NKF to receive access to tools and resources for both patients and professionals, discounts on professional education, and access to a network of thousands of individuals who treat patients with kidney disease.