Ultragenyx Pharmaceutical Inc. (RARE) Securities Fraud: Contact Berger Montague To Discuss Your Rights

Philadelphia, Pennsylvania--(Newsfile Corp. - February 24, 2026) - National plaintiffs' law firm Berger Montague PC announces that a class action lawsuit has been filed against Ultragenyx Pharmaceutical Inc. (NASDAQ: RARE) ("Ultragenyx" or the "Company") on behalf of investors who purchased Ultragenyx common stock during the period from August 3, 2023 through December 26, 2025 (the "Class Period").

Investor Deadline: Investors who purchased Ultragenyx securities during the Class Period may, no later than April 6, 2026, seek to be appointed as a lead plaintiff representative of the class. To learn your rights, CLICK HERE.

Headquartered in Novato, Calif., Ultragenyx is a biopharmaceutical company specializing in treatments for rare diseases.

According to the complaint, while publicly raising investor expectations about the ORBIT and COSMIC studies, which tested setrusumab as a treatment for Osteogenesis Imperfecta, Defendants misled investors by concealing that neither study significantly reduced the clinical fracture rates compared to control groups. Following the disclosure, Ultragenyx's share price plummeted from a close of $34.19 on December 26, 2025 to a close of $19.72 per share on December 29, erasing more than 42% of its value in a single day.

If you are a Ultragenyx investor and would like to learn more about this action, CLICK HERE or please contact Berger Montague: Andrew Abramowitz at [e-mail] or [phone], or Caitlin Adorni at [e-mail] or [phone].

About Berger Montague

Berger Montague is one of the nation's preeminent law firms focusing on complex civil litigation, class actions, and mass torts in federal and state courts throughout the United States. With more than $2.4 billion in 2025 post-trial judgments alone, the Firm is a leader in the fields of complex litigation, antitrust, consumer protection, defective products, environmental law, employment law, securities, and whistleblower cases, among many other practice areas. For over 55 years, Berger Montague has played leading roles in precedent-setting cases and has recovered over $50 billion for its clients and the classes they have represented. Berger Montague is headquartered in Philadelphia and has offices in Chicago; Malvern, PA; Minneapolis; San Diego; San Francisco; Toronto, Canada; Washington, D.C., and Wilmington, DE.

For more information or to discuss your rights, please contact:

Andrew Abramowitz
Berger Montague
[phone]
[e-mail]

Caitlin Adorni
Berger Montague
[phone]
[e-mail]

To view the source version of this press release, please visit https://www.newsfilecorp.com/release/284812

The Ultragenyx Pharmaceutical Stock at the time of publication of the news with a raise of +1,05 % to 19,30USD on Tradegate stock exchange (24. Februar 2026, 14:24 Uhr).