Rosen Law Firm Encourages Ultragenyx Investors to Secure Counsel Before April 6 Deadline

The firm reminds investors of the important deadline in a securities class action lawsuit against the pharmaceutical company.

Mar. 30, 2026 at 6:34pm

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A photorealistic studio still life featuring a stack of legal documents, a gavel, and a calculator on a clean, monochromatic background, conceptually representing the abstract ideas of corporate litigation, financial risk, and market uncertainty.A legal case against a pharmaceutical company highlights the need for investors to carefully scrutinize corporate disclosures.NYC Today

The Rosen Law Firm, a global investor rights law firm, is reminding purchasers of Ultragenyx Pharmaceutical Inc. (NASDAQ: RARE) common stock between August 3, 2023 and December 26, 2025 of the important April 6, 2026 lead plaintiff deadline in a securities class action lawsuit against the company.

Why it matters

The lawsuit alleges that Ultragenyx provided investors with materially false and misleading information about the potential of its drug setrusumab (UX 143) for treating Osteogenesis Imperfecta, causing shareholders to purchase the stock at artificially inflated prices.

The details

The lawsuit claims that Ultragenyx's statements about setrusumab's ability to decrease the annualized fracture rate in OI patients were misleading, as the drug's increase in bone density did not actually correlate to a decrease in fractures. The lawsuit alleges that when the true details entered the market, investors suffered damages.

  • The class period is from August 3, 2023 to December 26, 2025.
  • The lead plaintiff deadline is April 6, 2026.

The players

Rosen Law Firm

A global investor rights law firm that is representing investors in the class action lawsuit against Ultragenyx.

Ultragenyx Pharmaceutical Inc.

A biopharmaceutical company that is the defendant in the securities class action lawsuit.

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What they’re saying

“To join the Ultragenyx class action, go to https://rosenlegal.com/submit-form/?case_id=52472 or call Phillip Kim, Esq. toll-free at 866-767-3653 or email case@rosenlegal.com for information on the class action.”

— Phillip Kim, Esq.

What’s next

Investors have until April 6, 2026 to move the court to serve as the lead plaintiff in the class action lawsuit against Ultragenyx.

The takeaway

This case highlights the importance for investors to carefully review information provided by pharmaceutical companies and to seek qualified legal counsel if they believe they have been misled, in order to potentially recover losses.