#United States #Class Action #Securities Fraud #Radnor #Ultragenyx

Investor Alert on Ultragenyx Pharmaceutical Inc.: Class Action Lawsuit Filed

A recent class action lawsuit has emerged against Ultragenyx Pharmaceutical Inc. (NASDAQ: RARE), prompting concern among its investors. The accusations revolve around alleged securities fraud linked to their product, setrusumab, claiming that misleading statements were made regarding the drug's effectiveness during clinical trials.

The lawsuit, initiated by law firm Kessler Topaz Meltzer Check, LLP, specifically targets individuals who acquired stocks between August 3, 2023, and December 26, 2025. As the case unfolds in the United States District Court for the Northern District of California (Case No. 326-cv-01097), affected investors have until April 6, 2026, to assert their rights and seek lead plaintiff status in the class action.

Allegations of Misleading Statements

The core of the allegations is centered on claims that Ultragenyx presented optimistic and erroneous claims about setrusumab, particularly in its Phase III Orbit study concerning patients with varying types of Osteogenesis Imperfecta. Investors contend that the company

distorted the understanding of its clinical data, failing to adequately disclose significant risks that could impact the study results. The lawsuit asserts three primary points of contention:

1. False Impressions: Ultragenyx allegedly created a misleading narrative that it had reliable data regarding setrusumab's effects on patients while simultaneously minimizing the associated risks from Phase III trial outcomes.
2. Omitted Critical Information: It is claimed that the company's optimism regarding the Phase III results was unfounded as they neglectfully failed to share the potential inaccuracies linked to comparing Phase II results that lacked a placebo control group. This raises doubts about whether apparent improvements in patient outcomes could be attributed to other factors rather than the drug itself.
3. Misleading Statements on Operations: Defendants are accused of offering materially misleading information about the company’s prospects and operations, effectively downplaying critical risks inherent in their drug development processes.

The implications of these accusations are significant, as investors were led to believe in the potential of setrusumab without a clear understanding of the risks involved. Such allegations can severely impact investor trust and the company’s market reputation.

What Affected Investors Can Do

Those who feel affected by these developments have several paths forward:

• - File for Lead Plaintiff Status: Affected investors must act before April 6, 2026, to be considered for leading the class in this action. This typically involves demonstrating a substantial financial interest in the case.
• - Contact Legal Experts for Guidance: Kessler Topaz Meltzer Check, LLP offers free evaluations for those who experienced losses due to their engagement with Ultragenyx stocks. Investors are encouraged to reach out to discuss their options and next steps.

About the Law Firm: Kessler Topaz Meltzer Check, LLP

Kessler Topaz Meltzer Check, LLP specializes in securities fraud and class action lawsuits, representing both individual investors and larger institutions. Having established a strong reputation within the legal community, the firm has achieved significant recoveries for clients and has been recognized by several prestigious legal publications.

For more information or to evaluate your eligibility for participation in this case, investors can visit KTMC’s website or contact attorney Jonathan Naji directly via email or phone.

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This lawsuit underscores the importance of transparency and integrity in the pharmaceutical industry. As it unfolds, investors are reminded to stay informed and proactive about their rights and options.