SAN DIEGO / Nov 06, 2025 / Business Wire / Travere Therapeutics, Inc., (Nasdaq: TVTX) today announced new data from the Phase 3 DUPLEX Study demonstrating that patients with focal segmental glomerulosclerosis (FSGS) treated with FILSPARI® (sparsentan) were significantly more likely to reach proteinuria levels below 0.7 g/g compared to those receiving the maximum labeled dose of irbesartan, and achievement of this threshold correlated with reduced risk of kidney failure. The data were presented as a late-breaking poster at the American Society of Nephrology (ASN) Kidney Week 2025 in Houston, TX, November 6-9.
“We are pleased to present new data from the pivotal DUPLEX Study, highlighting the correlation between proteinuria reduction and the potential of FILSPARI to reduce long-term kidney failure events,” said Jula Inrig, M.D., chief medical officer of Travere Therapeutics. “People living with FSGS face a serious and progressive disease that often leads to kidney failure and dialysis. The PARASOL Project has determined that reducing proteinuria to the lowest possible levels is key to protecting kidney function in FSGS, and these analyses from the DUPLEX Study reinforce its findings."
The PARASOL Project previously identified urine protein-to-creatinine ratio (UPCR) below 0.7 g/g as a clinically meaningful proteinuria target in FSGS. This late-breaking poster reported the proportion of FILSPARI-treated patients reaching this threshold compared to the maximum labeled dose of irbesartan in the DUPLEX Study, and the effect of reaching this target on progression to kidney failure. A DUPLEX-aligned cohort of patients with FSGS (n=386) from the UK National Registry of Rare Kidney Disease (RaDaR) was then utilized to model the impact of achieving UPCR below 0.7 g/g on five-year kidney failure risk, during a 24-month period.
Key findings from the late-breaking analyses include:
In a separate oral presentation, the Company shared an analysis predicting the reduction in risk of kidney failure events at five-years for patients treated with FILSPARI based on the relative reduction in proteinuria from the DUPLEX Study. As previously published in the New England Journal of Medicine, the DUPLEX Study demonstrated that treatment with FILSPARI resulted in a clinically meaningful and durable reduction in proteinuria, with FSGS patients achieving a 50% reduction from baseline UPCR, compared to a 32% reduction with the maximum labeled dose of irbesartan. This translates to a 26% relative reduction in UPCR for FILSPARI-treated patients compared to the maximum labeled dose of irbesartan at 24 months. The analysis uses a DUPLEX-aligned cohort of patients from RaDaR to examine the correlation between reduction in proteinuria and the long-term risk of kidney failure.
Key findings from the RaDaR analysis include:
More information on Travere’s presence at ASN can be found here.
About the DUPLEX Study
The Phase 3 DUPLEX Study is the largest interventional study to date in FSGS, and the only study in FSGS against a maximally dosed active comparator. While DUPLEX achieved its pre-specified interim FSGS partial remission of proteinuria (FPRE) endpoint with statistical significance at 36 weeks, it did not achieve the primary efficacy eGFR slope endpoint over 108 weeks of treatment. The two-year results from the study were published in the New England Journal of Medicine and showed that FILSPARI delivered clinically meaningful benefit at 108 weeks with significant proteinuria reduction, higher rates of partial and complete remission, and a lower rate of end-stage kidney disease compared to active control. FILSPARI was well-tolerated with a safety profile that was consistent across all clinical trials conducted to date and comparable to the maximally dosed active control, irbesartan, including no drug-induced liver injury and no fluid overload. Patients who completed the DUPLEX double-blind portion of the study on treatment were eligible to participate in the open-label extension of the trial.
About Focal Segmental Glomerulosclerosis
Focal segmental glomerulosclerosis (FSGS) is a rare proteinuric kidney disorder in both children and adults that is estimated to affect more than 40,000 patients in the U.S. with similar prevalence in Europe. The disorder is defined by progressive scarring of the kidney and often leads to kidney failure. FSGS is characterized by proteinuria, where protein leaks into the urine due to a breakdown of the normal filtration mechanism in the kidney. Once in the urine, protein is considered to be toxic to other parts of the kidney, especially the tubules, and is believed to contribute to further disease progression. Other common symptoms include swelling in parts of the body, known as edema, as well as low blood albumin levels, abnormal lipid profiles and hypertension. FILSPARI is not approved for use in FSGS. There are currently no FDA-approved pharmacologic therapies for FSGS.
About Travere Therapeutics
At Travere Therapeutics, we are in rare for life. We are a biopharmaceutical company that comes together every day to help patients, families and caregivers of all backgrounds as they navigate life with a rare disease. On this path, we know the need for treatment options is urgent – that is why our global team works with the rare disease community to identify, develop and deliver life-changing therapies. In pursuit of this mission, we continuously seek to understand the diverse perspectives of rare patients and to courageously forge new paths to make a difference in their lives and provide hope – today and tomorrow. For more information, visit travere.com
FILSPARI® (sparsentan) U.S. Indication
FILSPARI (sparsentan) is indicated to slow kidney function decline in adults with primary immunoglobulin A nephropathy (IgAN) who are at risk for disease progression.
IMPORTANT SAFETY INFORMATION
BOXED WARNING: HEPATOTOXICITY AND EMBRYO-FETAL TOXICITY
Because of the risk of hepatotoxicity, FILSPARI is available only through a restricted program called the FILSPARI REMS. Under the FILSPARI REMS, prescribers, patients and pharmacies must enroll in the program.
Hepatotoxicity
Some Endothelin Receptor Antagonists (ERAs) have caused elevations of aminotransferases, hepatotoxicity, and liver failure. In clinical studies, elevations in aminotransferases (ALT or AST) of at least 3-times the Upper Limit of Normal (ULN) have been observed in up to 3.5% of FILSPARI-treated patients, including cases confirmed with rechallenge.
Measure transaminases and bilirubin before initiating treatment and then every 3 months during treatment. Interrupt treatment and closely monitor patients who develop aminotransferase elevations more than 3x ULN.
FILSPARI should generally be avoided in patients with elevated aminotransferases (>3x ULN) at baseline because monitoring for hepatotoxicity may be more difficult and these patients may be at increased risk for serious hepatotoxicity.
Embryo-Fetal Toxicity
FILSPARI is contraindicated for use during pregnancy because it may cause fetal harm if used by pregnant patients. Therefore, in patients who can become pregnant, exclude pregnancy prior to initiation of FILSPARI. Advise use of effective contraception before the initiation of treatment, during treatment, and for two weeks after discontinuation of treatment with FILSPARI. When pregnancy is detected, discontinue FILSPARI as soon as possible.
Contraindications
FILSPARI is contraindicated in patients who are pregnant. Do not coadminister FILSPARI with angiotensin receptor blockers (ARBs), ERAs, or aliskiren.
Warnings and Precautions
Most common adverse reactions
The most common adverse reactions (≥5%) are hyperkalemia, hypotension (including orthostatic hypotension), peripheral edema, dizziness, anemia, and acute kidney injury.
Drug interactions
Please see the full Prescribing Information, including BOXED WARNING, for additional Important Safety Information.
Forward Looking Statements
This press release contains “forward-looking statements” as that term is defined in the Private Securities Litigation Reform Act of 1995. Without limiting the foregoing, these statements are often identified by the words “on-track,” “positioned,” “look forward to,” “will,” “would,” “may,” “might,” “believes,” “anticipates,” “plans,” “expects,” “intends,” “potential,” or similar expressions. In addition, expressions of strategies, intentions or plans are also forward-looking statements. Such forward-looking statements include, but are not limited to, references to: statements relating to the clinical studies, models and data described herein; statements regarding the potential of FILSPARI to reduce long-term kidney failure events; statements regarding FILSPARI as a potential treatment for FSGS; and statements related to the estimated sizes of patient populations. Such forward-looking statements are based on current expectations and involve inherent risks and uncertainties, including factors that could delay, divert or change any of them, and could cause actual outcomes and results to differ materially from current expectations. No forward-looking statement can be guaranteed. Among the factors that could cause actual results to differ materially from those indicated in the forward-looking statements are risks and uncertainties related to the Company’s sNDA for FILSPARI in FSGS, including the timing and outcome thereof. There is no guarantee that the FDA will grant approval of FILSPARI for FSGS on the anticipated timeline, or at all. The Company also faces risks and uncertainties related to its business and finances in general, the success of its commercial products, risks and uncertainties associated with its preclinical and clinical stage pipeline, risks and uncertainties associated with the regulatory review and approval process, risks and uncertainties associated with enrollment of clinical trials for rare diseases, and risks that ongoing or planned clinical trials may not succeed or may be delayed for safety, regulatory or other reasons. Specifically, the Company faces risks associated with the ongoing commercial launch of FILSPARI in IgAN, the timing and potential outcome of its and its partners’ clinical studies, market acceptance of its commercial products including efficacy, safety, price, reimbursement, and benefit over competing therapies, risks related to the challenges of manufacturing scale-up, risks associated with the successful development and execution of commercial strategies for such products, including FILSPARI, and risks and uncertainties related to the new administration, including but not limited to risks and uncertainties related to tariffs and the funding, staffing and prioritization of resources at government agencies including the FDA. The Company also faces the risk that it will be unable to raise additional funding that may be required to complete development of any or all of its product candidates, including as a result of macroeconomic conditions; risks relating to the Company’s dependence on contractors for clinical drug supply and commercial manufacturing; uncertainties relating to patent protection and exclusivity periods and intellectual property rights of third parties; risks associated with regulatory interactions; and risks and uncertainties relating to competitive products, including current and potential future generic competition with certain of the Company’s products, and technological changes that may limit demand for the Company’s products. The Company also faces additional risks associated with global and macroeconomic conditions, including health epidemics and pandemics, including risks related to potential disruptions to clinical trials, commercialization activity, supply chain, and manufacturing operations. You are cautioned not to place undue reliance on these forward-looking statements as there are important factors that could cause actual results to differ materially from those in forward-looking statements, many of which are beyond our control. The Company undertakes no obligation to publicly update any forward-looking statement, whether as a result of new information, future events, or otherwise. Investors are referred to the full discussion of risks and uncertainties, including under the heading “Risk Factors,” as included in the Company’s most recent Form 10-K, Form 10-Q and other filings with the Securities and Exchange Commission.
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| Daily Change: | -0.96 -2.88 |
| Daily Volume: | 2,802,322 |
| Market Cap: | US$2.890B |
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