Ultragenyx Pharmaceutical Inc. Class Action Lawsuit
Company: Ultragenyx Pharmaceutical Inc.
Ticker: (NASDAQ) RARE
Class Action Period: August 3, 2023 - December 26, 2025
See If You Qualify For Monetary Reward
Join the Ultragenyx Pharmaceutical Inc. Class Action Lawsuit
CLASS ACTION PERIOD
August 3, 2023 - December 26, 2025
Allegations
According to the complaint, defendants provided overwhelmingly positive statements to investors while, at the same time, disseminating materially false and misleading statements and/or concealing material adverse facts concerning the true state of setrusumab’s potential and the true risk inherent in the study protocols put forth; notably, that, while setrusumab does increase material bone density, this increase does not correlate to a decrease in annualized fracture rates or otherwise the Phase III Orbit and Cosmic studies were much less likely to be able to demonstrate such a link than management claimed. On December 29, 2025, Ultragenyx announced that both its Phase III Orbit and Cosmic Studies had not “achieved statistical significance against the primary endpoints of reduction in annualized clinical fracture rate compared to placebo or bisphosphonates, respectively.” The Company attributed the study failure to a “low fracture rate in the placebo group” of Orbit and a trend that fell shy of statistical significance in Cosmic. Following this news, the price of Ultragenyx’s common stock declined dramatically. From a closing market price of $34.19 per share on December 26, 2025, Ultragenyx’s stock price fell to $19.72 per share on December 29, 2025, a decline of about 42.32% in the span of just a single day.
Eligibility
To join the lawsuit, you must have experienced a loss on Ultragenyx shares purchased within the class period specified above.
Lead Plaintiff Deadline
If you suffered a loss in Ultragenyx Pharmaceutical Inc. during the relevant time frame, you have until April 6, 2026 to request that the Court appoint you as lead plaintiff. Your ability to share in any recovery doesn't require that you serve as a lead plaintiff.
Frequently Asked Questions
- How do I join the lawsuit against Ultragenyx Pharmaceutical Inc. (NASDAQ: RARE)?
Investors who purchased shares of Ultragenyx Pharmaceutical Inc. (NASDAQ: RARE) during the class period (August 3, 2023 - December 26, 2025) can join by submitting their transaction details through this case page.
- Ensure your purchase falls within the class period
- Provide basic transaction and loss details
- Submit your information before the deadline
The lead plaintiff deadline for this case is April 6, 2026, so investors should act quickly to protect their rights.
- Who is eligible for the Ultragenyx Pharmaceutical Inc. lawsuit?
Anyone who bought shares of Ultragenyx Pharmaceutical Inc. (NASDAQ: RARE) during August 3, 2023 - December 26, 2025 and suffered financial losses may qualify.
- What is the lead plaintiff deadline to join the Ultragenyx Pharmaceutical Inc. case?
The lead plaintiff deadline for the Ultragenyx Pharmaceutical Inc. lawsuit is April 6, 2026. Investors should act quickly to avoid missing this deadline.
- What is the class period for Ultragenyx Pharmaceutical Inc.?
The class period for Ultragenyx Pharmaceutical Inc. (NASDAQ: RARE) is August 3, 2023 - December 26, 2025, during which investors may have been affected by alleged misconduct.
- Can I still join the Ultragenyx Pharmaceutical Inc. lawsuit if I sold my shares?
Yes. Investors who purchased Ultragenyx Pharmaceutical Inc. shares during August 3, 2023 - December 26, 2025 may still qualify, even if they sold their shares later.
- How much compensation can I receive from the Ultragenyx Pharmaceutical Inc. lawsuit?
Compensation depends on the total losses and the final settlement. Eligible investors in the Ultragenyx Pharmaceutical Inc. case may receive a portion of the recovery.
- Do I need to pay to participate in the Ultragenyx Pharmaceutical Inc. case?
No, most securities fraud cases involving Ultragenyx Pharmaceutical Inc. operate on a contingency basis, meaning there are no upfront costs unless there is a recovery.
- Will I need to appear in court for the Ultragenyx Pharmaceutical Inc. lawsuit?
In most cases, investors do not need to appear in court. The legal team manages the Ultragenyx Pharmaceutical Inc. case on behalf of participants.
- What documents are required for the Ultragenyx Pharmaceutical Inc. lawsuit?
To participate in the Ultragenyx Pharmaceutical Inc. lawsuit, investors may need to provide transaction records, purchase dates, number of shares, and loss details.
- What happens after I submit my trade information for Ultragenyx Pharmaceutical Inc.?
After submission, your details for the Ultragenyx Pharmaceutical Inc. case will be reviewed, and you may be contacted regarding eligibility or next steps.
- Is this legal advice for the Ultragenyx Pharmaceutical Inc. lawsuit?
No, this page provides information about the Ultragenyx Pharmaceutical Inc. case and does not constitute legal advice or create an attorney-client relationship.
- Why should I act quickly on the Ultragenyx Pharmaceutical Inc. case?
The lead plaintiff deadline for the Ultragenyx Pharmaceutical Inc. lawsuit is April 6, 2026. If you are an investor, you may have the opportunity to seek appointment as lead plaintiff or remain an absent class member.
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