The Gross Law Firm notifies investors that a class action has commenced in the United States District Court for the Northern District of California on behalf of shareholders of Ultragenyx Pharmaceutical Inc. who purchased common stock between August 3, 2023 and December 26, 2025.
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.
If you wish to choose counsel to represent you and the class, you must apply to be appointed lead plaintiff and be selected by the Court. The lead plaintiff will direct the litigation and participate in important decisions including whether to accept a settlement for the class in the action. The lead plaintiff will be selected from among applicants claiming the largest loss from investment in the respective securities during the class periods. Members of the class will be represented by the lead plaintiff and counsel chosen by the lead plaintiff. No class has yet been certified in the above action. Appointment as Lead Plaintiff is not required to partake in any recovery.
Shareholders have until April 6, 2026 to request that the court appoint them lead plaintiff.
To receive more information, please fill out the form.
