Benzinga | Feb 2, 2021 07:10AM EST

Travere Therapeutics Announces Achievement of Interim Proteinuria Endpoint in the Ongoing Phase 3 DUPLEX Study of Sparsentan in Focal Segmental Glomerulosclerosis

Sparsentan achieved statistically significant response on interim proteinuria endpoint compared to irbesartan after 36-weeks of treatment

To date in the study, sparsentan has been generally well-tolerated and has shown a safety profile comparable to irbesartan

Company to host conference call and webcast today at 8:30 a.m. ET

SAN DIEGO, Feb. 02, 2021 (GLOBE NEWSWIRE) -- Travere Therapeutics, Inc. (NASDAQ:TVTX) today announced that the Company's ongoing pivotal Phase 3 DUPLEX Study of sparsentan in focal segmental glomerulosclerosis (FSGS) achieved its pre-specified interim FSGS partial remission of proteinuria endpoint (FPRE) after 36 weeks of treatment. Sparsentan, an investigational product candidate, demonstrated a statistically significant response on FPRE compared to the active control, irbesartan (p=0.0094). Preliminary results from the interim analysis suggest that to date in the study, sparsentan has been generally well-tolerated and has shown a comparable safety profile to irbesartan. Based on the data from the interim analysis, the Company intends to pursue submissions for accelerated approval of sparsentan for FSGS. The Company plans to continue its engagement with regulators in the first half of 2021 to discuss the ongoing study and to establish next steps for filing with the available data set.

"For decades people living with FSGS have faced daily challenges in controlling proteinuria and a fear of progressing to transplant or dialysis because current treatment options are not enough," said Eric Dube, Ph.D., chief executive officer of Travere Therapeutics. "Today, we are very pleased to announce interim proteinuria results from the ongoing DUPLEX Study that demonstrate treatment with sparsentan can lead to significantly greater reductions in proteinuria compared to current standard of care. As we move ahead, our organization will be focused on maintaining high quality in this ongoing study, and on continuing our engagement with regulators to enable submissions for accelerated approval with the available data set."

Consistent with prior guidance, the Company is providing limited data from the interim analyses to maintain trial integrity in the ongoing study. In the DUPLEX Study, a total of 371 patients were randomized 1:1 to receive either sparsentan or irbesartan, the active control. The study protocol provided for an unblinded analysis to evaluate the interim efficacy endpoint -- the proportion of patients achieving FPRE, which is a clinically meaningful endpoint defined as urine protein-to-creatinine ratio (UP/C) ?1.5 g/g and a >40 percent reduction in UP/C from Baseline, at Week 36 -- following the first approximately 190 patients reaching 36 weeks of treatment. After 36 weeks of treatment, 42.0 percent of patients receiving sparsentan achieved FPRE, compared to 26.0 percent of irbesartan-treated patients (p=0.0094).

The confirmatory primary endpoint of the DUPLEX Study to support full regulatory approval is the rate of change in eGFR over 108 weeks of treatment. As of the time of the interim analyses, available long-term eGFR data for the confirmatory endpoint were limited. Consistent with the DUPLEX Study protocol, patients will continue in a blinded manner to assess the treatment effect on eGFR slope over 108 weeks in the confirmatory endpoint analysis.

A preliminary review of the interim safety results indicate sparsentan has been generally well-tolerated and the overall safety profiles in the study to date have been generally comparable between treatment groups.

"These interim results from the largest interventional study in FSGS to date build upon the foundational evidence generated by the Phase 2 DUET Study. We believe these data provide further support for the innovative approach of combining endothelin and angiotensin II receptor antagonism in a single molecule to treat the high unmet need in these rare kidney disorders," said Noah Rosenberg, M.D., chief medical officer of Travere Therapeutics. "I would like to thank the patients and their caregivers, investigators and site staff whose continued commitment is critical to reaching this milestone and to ultimately completing this important study for those living with FSGS."

The DUPLEX Study is fully enrolled and is scheduled to continue as planned on a blinded basis to assess the confirmatory eGFR endpoint after 108 weeks of treatment. Topline results from the confirmatory endpoint are expected in the first half of 2023. The Company is also evaluating sparsentan for the treatment of IgA nephropathy in the ongoing pivotal Phase 3 PROTECT Study, and topline efficacy data from the 36-week interim proteinuria endpoint analysis from that study are anticipated in the third quarter of 2021.