Jula Inrig, MD: New Data on the Burden of Immunoglobulin A Nephropathy

In this interview Jula Inrig, MD, Chief Medical Officer (CMO) of Travere Therapeutics, discussed data regarding immunoglobulin A (IgA) nephropathy (IgAN) presented at the 2022 American Society of Nephrology (ASN) Annual Meeting in Orlando.

Multiple studies assessed the novel investigational candidate Sparsentan, a Dual Endothelin Angiotensin Receptor Antagonist (DEARA) currently in phase 3 development for the treatment of IgA nephropathy.

Also known as Berger's disease, IgA nephropathy is a rare kidney condition caused by the accumulation of immunoglobin A within the kidneys resulting in inflammation. Without treatment, the function of the kidneys can become inhibited and their ability to filter waste from blood may be affected.

Inrig shared 2 key points from the recent data on the condition. Not only were the data collected from a large sample size of almost 1000 patients, but investigators were able to observe the natural disease course and see what happens in regards to their proteinuria levels.

"What was really important to demonstrate was even the patients who got their their proteinuria down to less than a gram per day didn't have a benign course," she explained, "about 25% of those patients reached kidney failure or death within 10 years."

"So, that's still a pretty heavy burden, even for patients who are getting their proteinuria down with what available treatments we have," Inrig continued. "About half of those patients reach that endpoint within 15 years. For these young patients who are in their 20s or 30s, in this registry, that's a significant thing that they're facing."

The second thing she highlighted was the humanistic burden of IgA nephropathy demonstrated in another study. For this investigation, patients and caregivers addressed the impact that the rare disease has had on them.

"I would say the most striking thing that came out, at least from my perspective, is that 98% of patients reported feeling fear or uncertainty about the future due to their disease," Inrig said.

These results could help to correct the misleading idea that IgA nephropathy is "relatively benign" and treatment isn't usually necessary, according to Inrig.

"Patients are getting diagnosed even when they're in lower range of the proteinuria, they're progressing," she said. "And patients are quite fearful about the future with this disease."

With these supporting data and the orphan drug designation for Sparsentan from the FDA Travere Therapeutics may be able to help address this unmet need.

"It's not just about Sparsentan coming available for these patients," Inrig explained. "There's lots of other excitement for the future and I think there's going to be a wave of potential available therapies that are really needed for patients with IGA nephropathy."