Drugmaker Ardelyx said on Wednesday that it has filed a lawsuit against the US Department of Health and Human Services and the Centers for Medicare and Medicaid Services (CMS) over their plan to include its kidney disease drugs in the Medicare payment bundle system,

The lawsuit claims that CMS's plan to include the drug, Xphozaahalong with all other oral-only phosphate lowering therapies in the End-Stage Renal Disease Prospective Payment System (ESRD) will “significantly and negatively impact patient choice of and timely access to important medications.”

ESRD is a payment system to reimburse the facilities that provide renal dialysis services.

Ardelyx claims drugs like Xphozah and other similar therapies are not administered by dialysis providers and cannot be taken during the delivery of maintenance dialysis.

Xphozah was approved in the US last year to treat high phosphate levels in patients with chronic kidney disease.