INVESTOR DEADLINE: Ultragenyx Pharmaceutical Inc. Investors with Substantial Losses Have Opportunity to Lead Class Action Lawsuit, Robbins Geller Rudman & Dowd LLP Announces - RARE

Core Viewpoint - Ultragenyx Pharmaceutical Inc. is facing a class action lawsuit due to alleged violations of the Securities Exchange Act of 1934, with claims that the company misled investors regarding the efficacy of its drug setrusumab for treating Osteogenesis Imperfecta [1] Summary by Relevant Sections Class Action Lawsuit Details - Investors who purchased Ultragenyx common stock between August 3, 2023, and December 26, 2025, have until April 6, 2026, to seek appointment as lead plaintiff in the class action lawsuit [1] - The lawsuit alleges that Ultragenyx and its executives made false statements and failed to disclose critical information about the Phase III Orbit study, which did not achieve statistically significant results [1] Allegations Against Ultragenyx - The lawsuit claims that Ultragenyx created a false impression of having reliable data on setrusumab's effects while downplaying the risks associated with the Phase III Orbit study [1] - On July 9, 2025, Ultragenyx disclosed that the Phase III Orbit study failed to achieve statistical significance, leading to a stock price drop of over 25% [1] - Further, on December 29, 2025, the company announced that both the Phase III Orbit and Cosmic studies did not meet primary endpoints, resulting in a stock price decline of more than 42% [1] Lead Plaintiff Process - The Private Securities Litigation Reform Act of 1995 allows any investor who acquired Ultragenyx common stock during the class period to seek lead plaintiff status, representing the interests of all class members [1] - The lead plaintiff can choose a law firm to litigate the case, and participation as lead plaintiff does not affect an investor's ability to share in any potential recovery [1] About Robbins Geller - Robbins Geller Rudman & Dowd LLP is a prominent law firm specializing in securities fraud and shareholder rights litigation, having recovered over $916 million for investors in 2025 alone [1] - The firm has a strong track record, recovering $8.4 billion for investors over the past five years, making it one of the largest plaintiffs' firms globally [1]