Ultragenyx Pharmaceutical Investors Seek Lead in Securities Class Action

Deadline for investors with substantial losses to lead lawsuit is April 6, 2026

Mar. 19, 2026 at 12:52pm

Got story updates? Submit your updates here. ›

Investors who purchased Ultragenyx Pharmaceutical Inc. (NASDAQ: RARE) common stock between August 3, 2023 and December 26, 2025 have until April 6, 2026 to seek appointment as lead plaintiff in a securities class action lawsuit against the company and certain executives. The lawsuit alleges Ultragenyx made false and misleading statements about the effects of its drug setrusumab on patients with Osteogenesis Imperfecta and minimized the risk that its Phase III Orbit study would fail to achieve a statistically significant reduction in annualized fracture rate.

Why it matters

This lawsuit highlights the risks investors face when companies allegedly make overly optimistic claims about the prospects of their experimental drugs. The failure of Ultragenyx's Phase III studies for setrusumab resulted in a significant drop in the company's stock price, causing substantial losses for investors.

The details

The class action lawsuit, captioned Bailey v. Ultragenyx Pharmaceutical Inc., No. 26-cv-01097 (N.D. Cal.), alleges that Ultragenyx and certain executives violated the Securities Exchange Act of 1934 by making false and misleading statements about the effects of setrusumab and the likelihood of success in the Phase III Orbit study. The lawsuit claims Ultragenyx failed to adequately convey the risks associated with basing the Orbit study's interim analysis on Phase II results that lacked a placebo control group for comparison.

  • The Class Period is from August 3, 2023 to December 26, 2025, inclusive.
  • The deadline for investors to seek appointment as lead plaintiff is Monday, April 6, 2026.

The players

Ultragenyx Pharmaceutical Inc.

A biopharmaceutical company that focuses on the identification, acquisition, development, and commercialization of novel products for the treatment of rare and ultra-rare genetic diseases.

Robbins Geller Rudman & Dowd LLP

A law firm representing the plaintiffs in the securities class action lawsuit against Ultragenyx.

Got photos? Submit your photos here. ›

What they’re saying

“If you suffered substantial losses and wish to serve as lead plaintiff of the Ultragenyx class action lawsuit, please provide your information here:”

— J.C. Sanchez, Attorney, Robbins Geller Rudman & Dowd LLP

What’s next

The judge will decide on April 6, 2026 whether to appoint a lead plaintiff for the securities class action lawsuit against Ultragenyx.

The takeaway

This case highlights the importance for biotech companies to be transparent about the risks and challenges associated with their drug development programs, in order to avoid misleading investors and exposing themselves to potential securities fraud lawsuits.