Vifor Licenses Rare Kidney Disease Drug in Comeback for Travere

Vifor Pharma and Travere Therapeutics inked a collaboration and licensing partnership to commercialize sparsentan in Europe, Australia and New Zealand. The drug is being developed to treat FSGS and IgAN, both rare progressive kidney diseases that are leading causes of end-stage kidney disease. Currently, there are no approved drugs for the two disorders.

In May, Traverse reported that after pre-New Drug Application (NDA) talks with the U.S. Food and Drug Administration (FDA) over possible accelerated approval for sparsentan, the FDA has said the available data wouldn’t support the accelerated approval at that time. In the Phase III DUPLEX Study, the drug had hit an interim proteinuria endpoint in FSGS.

“We remain very confident in the profile of sparsentan and believe it supports the ability to ultimately become a new treatment standard for FSGS, but we are disappointed that we will not be able to submit for accelerated approval this year and deliver it to patients on our original targeted timeline,” Eric Dube, Ph.D., chief executive officer of Travere, stated at that time.

Accelerated approval is typically designed based on a surrogate endpoint rather than a clinical benefit. It also usually requires post-market studies to maintain license or support. The rejection by the FDA of the Accelerated Approval pathway wasn’t a rejection of the drug. It was just an indication the agency did not feel the data at that point supported that approach.

On September 7, Travere announced that after a Type A meeting with the FDA, they plan to submit additional estimated glomerular filtration rate (eGFR) data from the ongoing Phase III DUPLEX Study for focal segmental glomerulosclerosis (FSGS) in support of accelerated approval in 2022.

“If the additional data further strengthen the prediction of long-term benefit in the study as we expect, we anticipate submitting a New Drug Application for accelerated approval of sparsentan for FSGS in the middle of next year and furthering our preparations to deliver it as a potential new treatment standard for FSGS, if approved,” Dube said.

The drug has received Orphan Drug Designation for the treatment of IgAN and FSGS in both the U.S. and Europe.

Under the terms of the deal with Vifor, Vifor will receive commercialization rights to sparsentan in Europe, Australia and New Zealand and pay Travere $55 million upfront. Travere will also be eligible for up to $135 million in various regulatory and market access milestones. Vifor will also make sales milestones and tiered double-digit royalties on net sales in the proposed market, with up to 40% at the high end of the royalty range.

“This agreement highlights that Vifor Pharma has become a company of choice for organizations committed to partnering innovative nephrology assets,” said Abbas Hussain, chief executive officer of Vifor. “With sparsentan, we will further expand our growing nephrology pipeline into FSGS and IgAN. There are currently no effective or approved therapies for these two rare kidney disorders, resulting in a significant unmet medical need among these patient populations. We look forward to working closely with Travere, who is responsible for the ongoing clinical development program of sparsentan, and to leveraging our commercial expertise to bring this up-and-coming, innovative treatment option to potentially more than 150,000 patients living with IgAN or FSGS in the licensed territories as soon as possible.”

Since the positive topline interim data from the ongoing PROTECT Phase III trial in IgAN, the two companies plan to continue evaluating the regulatory strategy for the drug in Europe. One possibility is submitting a joint marketing authorization application for both FSGS and IgAN in 2022. They expect that eventually the responsibility and control over marketing approvals in the licensed territories will be handled by Vifor. Vifor will handle all commercialization operations in the licensed regions if the drug is approved, while Travere will handle the clinical development. Travere also keeps all rights to the drug in the U.S. and the rest of the world.

Sparsentan is a dual endothelin angiotensin receptor antagonist (DEARA).