HIGH IMPACT – Travere hosted a call to discuss the recent regulatory update for sparsentan

  • Travere’s sparsentan was previously assigned a PDUFA target action date of November 17, 2022 for its NDA under accelerated approval for the treatment of IgAN, which has been extended by 3 months following late-cycle review interactions with the FDA.
  • The FDA has requested the company to update its proposed Risk Evaluation Mitigation Strategy (REMS) to include liver monitoring for sparsentan, consistent with some, but not all approved products in the endothelin receptor antagonist class. No additional clinical data or studies have been requested, but the updated submission is likely to be considered a major amendment to the NDA.
    • The REMS plan monitors risk of teratogenicity, as this is universal across endothelin receptor antagonists.
    • The FDA noted that there is added caution for sparsentan as it’s the first-time nephrologists will be using this class of medications.
  • Travere expects to submit an updated REMS plan in the coming days, and expects confirmation of a February 17th, 2023 PDUFA date from the FDA.
  • Travere says this request for additional monitoring within the REMS came unexpectedly, but its goal remains for sparsentan to become a new treatment standard for IgAN.

inThought Analysis

Travere’s timeline for sparsentan in the U.S. has been set back once again, following a recent announcement that the company will pursue traditional approval of sparsentan in the U.S. for its other indication FSGS, which is also expected in 2023. Travere has also applied to the EMA for IgAN with an expected decision in H2 2023 and plans to submit to the EMA for FSGS around that time, making 2023 an important year to keep an eye on for sparsentan in both the IgAN and FSGS space.

Despite the labeling update, there has not been strong evidence of liver toxicity with sparsentan. The phase 2 data showed mild elevation in liver enzymes. Although the phase 3 results aren’t yet clear, the company stated during the call that among 800 participants in the phase 3 studies, ALT/AST elevations were comparable between sparsentan and irbesartan. Although there is still a strong likelihood sparsentan will be approved (notably, Travere received a draft label), the updated REMS may slow uptake. Based on the complexities involved with administering a REMS program and the data requirements outlined, products with REMS requirements are frequently dispensed by specialty pharmacies in limited networks. Many traditional pharmacies do not have the ability to report on REMS appropriately and adhere to the FDA’s strict guidelines. However, if efficacy and safety of a product can be proven post-launch through other supplemental data provided to the FDA, REMS program requirements can be eliminated.

Chinook might also face the same REMS plan when they seek approval for atrasentan.

 

Source: Company Transcript