#United States #Robbins Geller #San Diego #Securities Class Action #Ultragenyx Inc.

Investors of Ultragenyx Pharmaceutical Inc. Have Legal Options

The law firm, Robbins Geller Rudman & Dowd LLP, recently made a significant announcement for investors of Ultragenyx Pharmaceutical Inc. (NASDAQ: RARE). If you acquired shares between August 3, 2023, and December 26, 2025, you might have a chance to lead a class action lawsuit as a result of considerable financial losses during this period. The deadline for expressing interest in a lead plaintiff role is April 6, 2026.

Background on the Lawsuit

The class action lawsuit in question is officially known as Bailey v. Ultragenyx Pharmaceutical Inc., which has been filed in the Northern District of California (No. 26-cv-01097). The complaint alleges that Ultragenyx, alongside specific top executives, violated the Securities Exchange Act of 1934.

Context of Allegations

Ultragenyx, a biopharmaceutical company dedicated to developing treatments for rare genetic disorders, is facing allegations concerning misleading statements and failures to disclose critical information about the Phase III Orbit study. Reportedly, the company created an impression of confidence regarding setrusumab’s effects on patients with Osteogenesis Imperfecta (OI). However, the truth remained obscured: they did not adequately communicate the risks inherent in the Phase III results, particularly since the data originated from a Phase II study lacking a placebo group for accurate comparison.

On July 9, 2025, Ultragenyx disclosed that the Phase III Orbit study did not yield statistically significant results for its second interim analysis. This revelation caused the stock to plummet by over 25%. Following this, on December 29, 2025, an announcement confirmed the significant failures of both the Orbit and Cosmic studies, which collectively drove the stock price down by over 42%.

The Lead Plaintiff Process

The Private Securities Litigation Reform Act of 1995 enables any investor who purchased or acquired Ultragenyx common stock during the specified period to seek the role of lead plaintiff in this lawsuit. The lead plaintiff is typically the one with the most substantial financial stake in the case and serves to represent all affected investors.

This individual will have the authority to select a law firm to manage the litigation process, although it’s important to note that investors' potential recovery isn’t contingent on their appointment as lead plaintiff.

To take action, those interested can provide their information through the form linked here or contact attorney J.C. Sanchez directly at Robbins Geller via phone at 800-449-4900 or by email.

About Robbins Geller

Robbins Geller Rudman & Dowd LLP stands as a leading firm in complex class action lawsuits, particularly focused on securities fraud and shareholder rights. The firm has collected over $916 million for investors in 2025 alone, reflecting their dominance in the field. With a team of 200 lawyers spanning ten offices, Robbins Geller has achieved numerous landmark recoveries in securities class actions, boasting a total recovery of $8.4 billion for investors in the last five years.

For those impacted by Ultragenyx’s recent legal troubles, this class action presents an opportunity not only to pursue potential financial return but also to hold the company accountable for its alleged improper practices. Investors are strongly encouraged to consider entering the lawsuit to reclaim their losses, joining a broader movement of accountability in the pharmaceutical sector.