Dr. Jula Inrig explains the mechanism of action for the Dual Endothelin Angiotensin Receptor Antagonist (DEARA) investigational candidate Sparsentan, for rare kidney diseases.
The novel investigational candidate Sparsentan is a Dual Endothelin Angiotensin Receptor Antagonist (DEARA) and has been supported by mutilple studies. It's now in phase 3 development for the treatment of immunoglobulin A (IgA) nephropathy (IgAN) and focal segmental glomerulosclerosis (FSGS), rare kidney diseases. Data were recently presented on the drug at the 2022 American Society of Nephrology (ASN) Annual Meeting in Orlando.
Jula Inrig, MD, Chief Medical Officer (CMO) of Travere Therapeutics, explained the function of Sparsentan for these conditions.
"Sparsentan is in development for IGA nephropathy and FSGS, and importantly, a little bit about the mechanism of action for people who may not be familiar with Sparsentan—it's a single molecule that has dual inhibition of both endo Thielen 1 and angiotensin 2," she explained. "I think it's important for folks to know that we have really good preclinical data in animal models of both IGA nephropathy and FSGS that demonstrates that Sparsentan can protect kidney function and structure, and has anti inflammatory, anti proliferative and anti fibrotic effects."
However, Travere Therapeutics, the developing company, has been limited in what data they're able to release because there are still large clinical trials currently in development.
"Particularly in IGA nephropathy, we're under the accelerated approval pathway," Inrig said, "and what that means is we get approval—potentially—on a surrogate endpoint with the trials still ongoing with potential for full approval once those trials complete."
In regard to FSGS, data have recently been released on the promising phase 2 data evaluating the safety and efficacy of patients who were undergoing therapy for up to 7 years.
"What we were able to demonstrate is a significant effect over the long term in these patients with regards to proteinuria reduction," she stated. "Over the 4 years, we see them continuing to have a decline in proteinuria, at 4 years they're at 50%, and about 68% of patients achieving a modified partial remission of endpoint in 4 years."