Security Investigation
Ultragenyx Pharmaceutical Inc. (NasdaqGS: RARE)
59 Days left to seek lead plaintiff status.
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Kahn Swick & Foti, LLC (“KSF”) and KSF partner, former Attorney General of Louisiana, Charles C. Foti, Jr., notifies investors in Ultragenyx Pharmaceutical Inc. (“Ultragenyx” or the “Company”) (NasdaqGS: RARE) of a class action securities lawsuit.
The lawsuit seeks to recover losses on behalf of investors of Ultragenyx who were adversely affected by alleged securities fraud between August 3, 2023 and December 26, 2025.
On December 26, 2025, the Company announced the “results from the Phase 3 Orbit and Cosmic studies for setrusumab (UX143) in Osteogenesis Imperfecta” disclosing that both its Phase III Orbit and Cosmic studies failed to demonstrate that setrusumab triggered a statistically significant reduction in annualized fracture rates for patients with osteogenesis imperfecta, and, as a result the Company “is evaluating its planned operations and will promptly define and implement significant expense reductions.” On this news, the price of Ultragenyx’s shares fell approximately 42%, from $34.19 per share on December 26, 2025 to $19.72 per share on December 29, 2025.
If you invested in Ultragenyx and suffered a loss during the relevant time frame, you have until April 6, 2026 to request that the Court appoint you as lead plaintiff; however, your ability to share in any recovery does not require that you serve as a lead plaintiff. Ultragenyx investors should contact KSF Managing Partner Lewis Kahn toll-free at 1-877-515-1850 or via email (lewis.kahn@ksfcounsel.com), or fill out the form on this page.
The case is Steven Bailey v. Ultragenyx Pharmaceutical Inc., et al., No. 26-cv-01097.