Travere Therapeutics presented new data at the American Society of Nephrology (ASN) Kidney Week 2024, reinforcing the clinical benefits of FILSPARI (sparsentan) in IgA nephropathy (IgAN) and highlighting its potential in focal segmental glomerulosclerosis (FSGS). The data encompass findings from the SPARTAN, SPARTACUS, PROTECT, and DUPLEX studies, evaluating sparsentan's efficacy and safety in various IgAN treatment scenarios and FSGS.
FILSPARI as First-Line Therapy in IgAN
The SPARTAN study evaluated FILSPARI as a first-line therapy in newly diagnosed, RASi-naïve IgAN patients. Results showed a rapid and sustained reduction in proteinuria of approximately 70% from baseline over 24 weeks. Notably, nearly 60% of patients achieved complete remission of proteinuria at any point during the treatment period, with a stable estimated glomerular filtration rate (eGFR) throughout the study duration.
Combination Therapy with FILSPARI in IgAN
Interim data from the SPARTACUS study demonstrated that FILSPARI, when added to a stable SGLT2 inhibitor regimen, was generally well-tolerated. Approximately one-third of patients experienced at least a 50% reduction in proteinuria, and two-thirds had at least a 30% reduction after 24 weeks of treatment. Data from the ongoing PROTECT study's open-label extension and real-world use further supported the favorable safety profile and additive efficacy of combining SGLT2 inhibitors or immunosuppressants with FILSPARI.
Sparsentan in Genetic FSGS
A late-breaking presentation from the DUPLEX study focused on a subset of patients with genetic mutations in podocyte proteins, representing a high-risk, treatment-resistant form of FSGS. Sparsentan delivered a rapid and sustained proteinuria reduction in these patients, with some achieving complete remission and experiencing long-term kidney health benefits. Additionally, an analysis of patient-reported outcomes from 306 adult patients in the DUPLEX study indicated that health-related quality of life remained stable over the two-year treatment period, and the burden of kidney disease improved compared to those receiving irbesartan.
EPPIK Study in Pediatric Patients
Preliminary data from the EPPIK Study showed that children with a range of rare proteinuric glomerular diseases treated with sparsentan experienced rapid and robust proteinuria reduction of approximately 50% over 12 weeks.
About IgAN and FSGS
IgA nephropathy (IgAN), or Berger's disease, is a rare progressive kidney disease affecting up to 150,000 people in the U.S. It is characterized by the buildup of immunoglobulin A (IgA) in the kidneys, leading to impaired filtering mechanisms, blood in the urine (hematuria), protein in the urine (proteinuria), and progressive loss of kidney function. Focal segmental glomerulosclerosis (FSGS) is another rare proteinuric kidney disorder affecting more than 40,000 patients in the US and Europe. It is defined by progressive scarring of the kidney and often leads to kidney failure. There is currently no approved pharmacologic indicated for the treatment of FSGS.
Travere Therapeutics' Perspective
"The data presented at ASN provided additional evidence that FILSPARI is effective across all subgroups of IgAN patients studied to-date, and that it achieved significant levels of complete remission when used in newly diagnosed patients," said Jula Inrig, M.D., chief medical officer of Travere Therapeutics. "We also shared initial data showing that FILSPARI safely induced further proteinuria reduction when used with SGLT2 inhibitors or steroids, supportive of the flexibility to be used in combination with other medicines as needed. Furthermore, we shared data exploring a subgroup of genetic FSGS patients in our DUPLEX Study. Genetic FSGS patients are often treatment resistant so the significant reductions in proteinuria and benefit on outcomes reported in this group are very encouraging."
