Ardelyx has filed a lawsuit against the U.S. Department of Health and Human Services and the Centers for Medicare and Medicaid Services regarding their plan to include the company's kidney disease drug, Xphozah (tenapanor), in the Medicare payment bundle system.

According to the lawsuit, the Centers for Medicare and Medicaid Services (CMS)'s decision to include Xphozah and other oral-only phosphate-lowering therapies in the End-Stage Renal Disease Prospective Payment System (ESRD PPS) will "significantly and negatively impact patient choice of and timely access to important medications." The ESRD PPS is a payment system designed to reimburse facilities that provide renal dialysis services.

Ardelyx claims that drugs like Xphozah and similar therapies are not administered by dialysis providers and cannot be taken during the delivery of maintenance dialysis, making their inclusion in the bundled payment system problematic.

Xphozah received approval in the United States last year for the treatment of high phosphate levels in patients with chronic kidney disease. The CMS recently updated its regulations to include oral-only end-stage renal disease drugs and therapies in the bundled payment system, with the changes set to take effect on January 1, 2025.

The lawsuit filed by Ardelyx aims to challenge the inclusion of Xphozah and similar therapies in the ESRD PPS, asserting that it will have negative consequences for patients who rely on these medications.