Ardelyx (NASDAQ: ARDX) Securities Class Action: Investor Rights and November 16, 2026 Lead Plaintiff Deadline

The complaint alleges that Ardelyx and certain executives made positive statements concerning the company's commercial growth and ability to achieve projected revenue and longer-term growth expectations for IBSRELA and XPHOZAH while allegedly failing to adequately disclose increasing barriers to patient access.

The complaint focuses on alleged increases in:

• payer-related access barriers;
• reimbursement restrictions;
• prior-authorization requirements;
• step-edit requirements;
• delays in new-patient starts; and
• prescription-fulfillment delays.

The plaintiff contends these circumstances made certain statements concerning commercial growth, patient access, and long-term product opportunities materially false or misleading. These allegations have not been proven.

Ardelyx is a commercial-stage biopharmaceutical company.

IBSRELA (tenapanor) is used to treat irritable bowel syndrome with constipation in adults.

XPHOZAH (tenapanor) is used to reduce serum phosphorus in certain adults with chronic kidney disease on dialysis.

Ardelyx is incorporated in Delaware and trades on Nasdaq under the ticker ARDX.

XPHOZAH's reimbursement environment changed substantially shortly before the new alleged securities class period.

Effective January 1, 2025, XPHOZAH became part of Medicare's ESRD bundled-payment system.

Ardelyx challenged CMS's treatment of the drug in federal court. On June 26, 2026, the D.C. Circuit affirmed dismissal of Ardelyx's challenge. The company later announced that it would not pursue further litigation concerning the reimbursement classification.

This provides important background regarding XPHOZAH's reimbursement and patient-access environment but does not itself establish the allegations in the new securities lawsuit.

The complaint identifies Ardelyx's August 6, 2026 earnings announcement as a principal alleged corrective disclosure.

Ardelyx reduced full-year 2026 IBSRELA revenue guidance from approximately $410–$430 million to $350–$370 million. The company also withdrew its previous $750 million long-term XPHOZAH revenue target.

Management linked the IBSRELA shortfall in part to significantly increased payer utilization-management processes affecting patient access and new-patient starts.

According to the complaint, ARDX declined from approximately $4.87 on August 6 to $4.00 on August 7 — a decline of approximately 18%.

Ardelyx's August 6 release also contained positive operating results. The company reported:

• approximately $118.1 million in quarterly product revenue;
• approximately $86.2 million in IBSRELA revenue;
• approximately $31.9 million in XPHOZAH revenue;
• continued 2026 XPHOZAH guidance of $110–$120 million; and
• continued belief that IBSRELA may eventually reach $1 billion in annual sales.

CEO Michael Raab stated that IBSRELA demand remained strong but described increased payer utilization-management processes.

The plaintiff's theory is not simply that Ardelyx's business collapsed, but that allegedly adverse facts concerning those payer barriers should have been disclosed earlier.

Section 10(b) and Rule 10b-5

The complaint asserts federal securities-fraud claims under Section 10(b) and Rule 10b-5 of the Securities Exchange Act of 1934.

Section 20(a)

The complaint also asserts controlling-person claims against the individual defendants under Section 20(a).

The complaint currently seeks to represent investors who purchased or otherwise acquired Ardelyx common stock between January 13, 2025 and August 6, 2026, inclusive, and suffered damages.

Investors should preserve complete brokerage statements and trade confirmations.

The currently published PSLRA lead plaintiff deadline is November 16, 2026. A lead plaintiff is the court-appointed investor or investor group that actively represents the proposed securities class and supervises class counsel.

Do I Have to Become Lead Plaintiff?

Generally, no. Most investors remain passive class members. An investor generally does not need to seek lead-plaintiff appointment merely to remain potentially eligible for a later class recovery.

Lead Plaintiff Deadline ≠ Settlement Claim Deadline

Investors with meaningful ARDX losses who want an active role may wish to evaluate lead-plaintiff appointment before November 16, 2026.

No. Ardelyx was previously involved in a different securities class action, Yarborough v. Ardelyx, Inc. That lawsuit concerned statements regarding whether Ardelyx would pursue TDAPA treatment for XPHOZAH.

The earlier securities case was ultimately dismissed with prejudice, and the subsequent First Circuit appeal was voluntarily dismissed in March 2026.

The new Broadwater case involves a different alleged class period and focuses primarily on payer access, utilization-management restrictions, prior authorization, new-patient starts, and revenue guidance.

Yes. Two shareholder derivative cases filed in 2024 were consolidated as In re Ardelyx, Inc. Stockholder Derivative Litigation. The derivative proceedings were stayed during the prior securities litigation and were dismissed pursuant to stipulation in April 2026.

Julie & Holleman's current investigation concerns whether newly alleged conduct and subsequent events may give current Ardelyx shareholders additional rights.

Potentially. Derivative standing is not determined solely by whether an investor owned ARDX before January 13, 2025.

Under Delaware law, a shareholder generally must have owned shares at the time of the particular challenged conduct and continue to own shares. Accordingly, an investor who bought ARDX after the beginning of the securities class period could potentially have standing concerning later conduct occurring while that investor held stock.

Julie & Holleman LLP is investigating potential shareholder derivative claims and corporate-governance claims on behalf of shareholders who owned Ardelyx stock at the time of potentially actionable conduct and have continued to hold their shares.

Potential areas of investigation may include:

• what management knew about payer-access restrictions and when;
• what information reached the board;
• how Ardelyx monitored reimbursement risk;
• how prior-authorization and step-edit trends were reported;
• prescription-fulfillment information;
• board oversight of major commercial risks;
• corporate disclosure decisions; and
• whether alleged misconduct caused harm to Ardelyx itself.

Counsel may also evaluate whether a Delaware books-and-records investigation or other investigative steps are appropriate. No determination has been made that a viable derivative claim exists.

Julie & Holleman LLP is investigating allegations involving Ardelyx, IBSRELA, XPHOZAH, payer restrictions, reimbursement, patient access, prior authorization, prescription fulfillment, and revenue guidance. We are interested in hearing from:

Investors With Securities Losses

Investors who purchased or otherwise acquired ARDX from January 13, 2025 through August 6, 2026 and suffered losses, including investors considering whether to seek lead-plaintiff appointment before November 16, 2026.

Current and Long-Term Ardelyx Shareholders

Shareholders who owned ARDX at the time of potentially actionable conduct and have continued to hold their shares, concerning potential derivative and corporate-governance rights.

A shareholder may potentially fall within both groups.