Ardelyx, Inc. NASDAQ: ARDX

A securities class action has been filed against Ardelyx, Inc. (“Ardelyx” or the “Company”) (NASDAQ: ARDX) on behalf of investors who purchased or otherwise acquired the Company's securities between January 13, 2025 and August 6, 2026, inclusive (the “Class Period”). Ardelyx is a biopharmaceutical company that markets IBSRELA (tenapanor), a treatment for irritable bowel syndrome with constipation, and XPHOZAH (tenapanor), a treatment for hyperphosphatemia in adults with chronic kidney disease on dialysis.

The complaint alleges that, throughout the Class Period, defendants made materially false and misleading statements and/or failed to disclose the true state of Ardelyx's commercial performance and growth prospects for IBSRELA and XPHOZAH — in particular, increasing payer-related access and reimbursement barriers affecting patient access, along with more stringent prior authorization and step-edit requirements that slowed new-patient starts and delayed prescription fulfillment.

On August 6, 2026, Ardelyx reduced its full-year 2026 IBSRELA revenue guidance and withdrew its long-term XPHOZAH revenue guidance, attributing the change to significantly increased payer utilization-management processes that restricted patient access and slowed new-patient starts, and citing “evolving market dynamics” for the XPHOZAH withdrawal. On this news, Ardelyx's stock price fell from a $4.87 close on August 6, 2026 to $4.00 per share on August 7, 2026, a decline of approximately 18% in a single trading day.