Ligand Pharmaceuticals Announces Positive Interim Results from Pivotal Phase 3 PROTECT Study of Sparsentan

Strategic Insights -

Ligand Pharmaceuticals Incorporated, a biotechnology company, has announced positive topline interim results from the ongoing pivotal Phase 3 PROTECT Study of sparsentan, an investigational product candidate for the treatment of IgA nephropathy (IgAN). The study, conducted by Travere Therapeutics, Inc., met its pre-specified interim primary efficacy endpoint with statistical significance, demonstrating a greater than threefold reduction of proteinuria from baseline after 36 weeks of treatment, compared to the active control irbesartan.

Key Takeaways:

  • The PROTECT Study, conducted by Travere Therapeutics, met its pre-specified interim primary efficacy endpoint, demonstrating a 49.8% mean reduction of proteinuria from baseline after 36 weeks of treatment in patients receiving sparsentan, compared to a 15.1% mean reduction in proteinuria from baseline for irbesartan-treated patients (p=0.0001).
  • A total of 404 patients with persistent proteinuria despite active ACE or ARB treatment were randomized 1:1 to receive once daily oral doses of either sparsentan or irbesartan.
  • The study protocol provided for an unblinded analysis to evaluate the interim efficacy endpoint - the change in proteinuria (urine protein-to-creatinine ratio, or "UPCR") at Week 36 from baseline - following the first approximately 280 patients reaching 36 weeks of treatment.
  • Travere Therapeutics believes that preliminary eGFR data available at the time of the interim analysis are indicative of a potential clinically meaningful treatment effect after two years of treatment.
  • The PROTECT Study will continue in a blinded manner to fully assess the treatment effect on eGFR slope over 110 weeks in the confirmatory endpoint analysis, and topline results from this analysis are expected in the second half of 2023.
  • A preliminary review of the interim safety results indicates that sparsentan has been generally well-tolerated and consistent with the previously observed safety profile with no new safety signals emerging.

Statistics:

  • 404 patients with persistent proteinuria despite active ACE or ARB treatment were randomized 1:1 to receive once daily oral doses of either sparsentan or irbesartan.
  • 49.8% mean reduction of proteinuria from baseline after 36 weeks of treatment in patients receiving sparsentan (p=0.0001).
  • 15.1% mean reduction in proteinuria from baseline for irbesartan-treated patients.
  • 280 patients reached 36 weeks of treatment.

Sources:

  • FORM 8-K (Current Report) filed by Ligand Pharmaceuticals Incorporated with the Securities and Exchange Commission on August 16, 2021.
  • Travere Therapeutics, Inc. press release announcing positive interim results from the PROTECT Study.