The sharp decline followed an August 6 announcement in which Ardelyx lowered its full-year revenue guidance for IBSRELA from a range of $410–$430 million to $350–$370 million. Management attributed the $80 million shortfall to unforeseen payer utilization-management hurdles, specifically citing increased step edits and stringent prior authorizations that stalled new-patient enrollment. During the earnings call, executives acknowledged that the severity of these restrictions was not something they had anticipated.

Law firm Levi & Korsinsky is now probing whether Ardelyx provided investors with accurate, transparent information regarding these developing headwinds before the guidance reduction. The investigation focuses on whether the company misled shareholders by reiterating previous revenue outlooks while internal pressures were already mounting. Investors who sustained losses during this period are now being evaluated for potential legal claims, with eligibility extending to those who sold their shares as well as current holders.