---
title: "Ardelyx securities suit over Xphozah ends"
url: "https://aibio.space/news/ardelyx-securities-suit-xphozah-ends-after-appeal-withdrawn/"
publisher: "aibio.space (Biotech Investor Relations News)"
date: "2026-08-06"
section: "Legal"
tickers: "NASDAQ:ARDX"
source: "https://www.sec.gov/Archives/edgar/data/1437402/000143740226000044/ardx-20260630.htm"
summary: "Yarborough v. Ardelyx named the company and executives Michael Raab, Susan Rodriguez, Laura Williams and Elizabeth Grammer. The First Circuit appeal was di"
---

By the aibio.space news desk.

Sources

- [Ardelyx 10-Q for the quarter ended June 30, 2026 (SEC EDGAR)](https://www.sec.gov/Archives/edgar/data/1437402/000143740226000044/ardx-20260630.htm)
- [Ardelyx proxy statement filed April 29, 2024 (SEC EDGAR)](https://www.sec.gov/Archives/edgar/data/1437402/000114036124023095/ny20024289x1_def14a.htm)
- [Ardelyx 10-K for the year ended December 31, 2024 (SEC EDGAR)](https://www.sec.gov/Archives/edgar/data/1437402/000162828025006653/ardx-20241231.htm)

[ARDX](https://aibio.space/companies/ardelyx/)

2026-08-06

# Ardelyx securities suit over Xphozah ends after appeal is withdrawn

Tickers [ARDX](https://aibio.space/companies/ardelyx/)

Yarborough v. Ardelyx named the company and executives Michael Raab, Susan Rodriguez, Laura Williams and Elizabeth Grammer. The First Circuit appeal was dismissed on March 26, 2026.

## Key facts

- **Company**: Ardelyx, Inc. (NASDAQ: ARDX)

- **News type**: Legal

- **Primary source**: [Ardelyx 10-Q for the quarter ended June 30, 2026 (SEC EDGAR)](https://www.sec.gov/Archives/edgar/data/1437402/000143740226000044/ardx-20260630.htm)

*The stone facade of a federal building. Photo: Carol M Highsmith, CC0, via rawpixel. The picture shows the field, not the companies named.*

Ardelyx, Inc. (Nasdaq: [ARDX](https://aibio.space/companies/ardelyx/)) said in its [10-Q filed August 6, 2026](https://www.sec.gov/Archives/edgar/data/1437402/000143740226000044/ardx-20260630.htm) that the securities class action Yarborough v. Ardelyx, Inc., et al., No. 24-cv-12119, is over. The U.S. District Court for the District of Massachusetts dismissed it with prejudice on December 24, 2025. After the plaintiffs appealed to the First Circuit, the court granted the parties' stipulated voluntary dismissal of that appeal on March 26, 2026. A consolidated shareholder derivative case based on substantially the same allegations was dismissed on April 9, 2026.

The amended complaint names Ardelyx, Michael Raab, Susan Rodriguez, Laura Williams and Elizabeth Grammer as defendants. Justin Renz was a defendant in the original complaint and was removed from the amended one.

## The case

A complaint was filed on August 16, 2024. It alleges violations of Sections 10(b) and 20(a) of the Exchange Act and Rule 10b-5. It relates to Ardelyx's announcement on July 2, 2024 that it had chosen not to file an application for a Transitional Drug Add-on Payment Adjustment for Xphozah. The plaintiffs sought damages and interest and an award of costs, including attorneys' fees.

The court appointed Tate Wood as lead plaintiff on October 30, 2024. His amended complaint, filed January 13, 2025, purported to cover everyone who acquired Ardelyx common stock between February 22, 2024 and July 1, 2024.

## Defendants

The company's [10-K filed February 20, 2025](https://www.sec.gov/Archives/edgar/data/1437402/000162828025006653/ardx-20241231.htm) is signed by Michael Raab as president, chief executive officer and director. The same filing signs Justin Renz as chief financial and operations officer. The company's [proxy statement filed April 29, 2024](https://www.sec.gov/Archives/edgar/data/1437402/000114036124023095/ny20024289x1_def14a.htm) lists Susan Rodriguez as chief commercial officer, Laura Williams, M.D., M.P.H., as chief medical officer and Elizabeth Grammer, Esq., as chief legal and administrative officer.

The 10-Q does not name the individual defendants in the derivative suits, which it describes as "certain members of our board of directors and management." The April 2024 proxy listed eight directors: Michael Raab, David Mott, William A. Bertrand, Jr., Onaiza Cadoret-Manier, Jan Lundberg, Ph.D., Robert Bazemore, Muna Bhanji and Richard Rodgers. It said Lundberg would cease being a director at the conclusion of the 2024 annual meeting. The other seven signed the 10-K as directors in February 2025, with Mott as chairman. No filing we reviewed says which of them were sued.

## Where it stands

Defendants moved to dismiss the amended complaint on March 14, 2025, and the court held a hearing on September 25, 2025. Plaintiffs appealed on January 21, 2026. The two derivative complaints, filed September 6 and 13, 2024, were consolidated on September 25, 2024 as In re Ardelyx, Inc. Stockholder Derivative Litigation, Case No. 1:24-cv-12302-LTS. The court stayed that case on November 7, 2024 and dismissed it on April 9, 2026 under a stipulation.

## Why it matters to shareholders

Ardelyx says that as of June 30, 2026, "there is no litigation pending that would reasonably be expected to have a material adverse effect" on its results of operations and financial condition. The 10-Q reports no settlement payment in any of these cases.

## Related matters

Earlier securities class actions, Strezsak v. Ardelyx, Inc. and Siegel v. Ardelyx, Inc., were voluntarily dismissed on March 5, 2025. Their companion derivative cases, Go v. Raab and Morris v. Raab, were dismissed on April 30, 2025. Separately, Ardelyx sued the Centers for Medicare and Medicaid Services in July 2024 over Xphozah's inclusion in the dialysis payment bundle. The suit, brought with the American Association of Kidney Patients and the National Minority Quality Forum in the District of Columbia, lost in the district court, which granted the defendants' motion to dismiss on November 8, 2024. The appeals court heard argument on September 25, 2025 and affirmed the dismissal on June 26, 2026. The company says it is not pursuing further litigation.

[Report an error](https://aibio.space/reputation/#correction)

## Companies in this story

ARDX

Ardelyx, Inc.

NASDAQ · United States

Open the starter desk

## More in Legal

Legal

### [Alnylam details Texas patent suit, two Cipla patent cases and a U.S. Attorney subpoena](https://aibio.space/news/alnylam-details-texas-patent-suit-two-cipla-patent-cases-u-s-attorney/)

Oct 29, 2026

Legal

### [Viking and Ligand dispute VK2809 license termination in San Diego court](https://aibio.space/news/viking-ligand-dispute-vk2809-license-termination-san-diego-court/)

Oct 29, 2026

Legal

### [Viking's ITC trade secret ruling against Ascletis is on appeal at Federal Circuit](https://aibio.space/news/vikings-itc-trade-secret-ruling-against-ascletis-appeal-federal/)

Oct 29, 2026

---
Source page: https://aibio.space/news/ardelyx-securities-suit-xphozah-ends-after-appeal-withdrawn/. Facts in aibio.space stories are checked against company filings and releases; opinion is labelled. Cite as: aibio.space, "Ardelyx securities suit over Xphozah ends", 2026-08-06, https://aibio.space/news/ardelyx-securities-suit-xphozah-ends-after-appeal-withdrawn/
