Core Viewpoint - A class action lawsuit has been filed against Ultragenyx Pharmaceutical Inc. on behalf of investors who purchased its common stock during the specified Class Period from August 3, 2023, to December 26, 2025 [1][2]. Company Overview - Ultragenyx Pharmaceutical Inc. is a biopharmaceutical company focused on acquiring and developing novel products for the treatment of rare genetic diseases, headquartered in Novato, California [2]. Lawsuit Details - The lawsuit claims that throughout the Class Period, Ultragenyx made overwhelmingly positive statements regarding the ORBIT and COSMIC Phase 3 clinical trials for setrusumab, intended to treat Osteogenesis Imperfecta [3]. - On December 29, 2025, Ultragenyx disclosed that neither clinical trial achieved its primary endpoint of reducing the annualized clinical fracture rate, resulting in a significant share price drop of over 42%, from $34.19 per share on December 26, 2025, to $19.72 per share on December 29, 2025 [4].

Core Viewpoint - The complaint against Ultragenyx alleges violations of federal securities laws due to misleading statements regarding the efficacy of setrusumab in treating Osteogenesis Imperfecta, particularly concerning the Phase III Orbit study results and the associated risks [2]. Group 1: Allegations and Misleading Information - The complaint claims that Ultragenyx and its executives created a false impression of having reliable information about setrusumab's effects on patients with Osteogenesis Imperfecta [2]. - It is alleged that Ultragenyx downplayed the risk that patients in the Phase III Orbit study would not achieve a statistically significant reduction in annualized fracture rate, which is critical for the study's interim analysis [2]. - The optimism expressed by Ultragenyx regarding the Phase III Orbit study's results is said to be misplaced, as the company failed to adequately disclose the risks associated with relying on Phase II results that lacked a placebo control group [2]. Group 2: Legal Proceedings and Class Action - The lead plaintiff in the class action is the investor with the largest financial interest in the relief sought, who will oversee the litigation on behalf of the class [3]. - Any member of the putative class has the option to move the court to serve as lead plaintiff or remain an absent class member without affecting their ability to share in any recovery [3]. Group 3: Whistleblower Encouragement - The law firm Faruqi & Faruqi encourages individuals with information regarding Ultragenyx's conduct, including whistleblowers and former employees, to come forward [4].

Core Viewpoint - Ultragenyx Pharmaceutical Inc. is facing a lawsuit for alleged violations of securities laws, which may impact its financial standing and investor confidence [1] Group 1 - The lawsuit has been initiated by the DJS Law Group, indicating potential legal challenges for the company [1] - The allegations pertain to securities law violations, which could lead to significant financial repercussions for Ultragenyx [1] - Investors are encouraged to discuss their rights in light of the ongoing legal situation [1]

Core Viewpoint - A class action has been filed against Ultragenyx Pharmaceutical Inc. for allegedly misleading investors regarding the efficacy of setrusumab in clinical studies, leading to significant stock price decline after the announcement of study failures [1][4]. Group 1: Allegations and Misleading Information - Robbins LLP is investigating allegations that Ultragenyx misled investors about the expected results of its Phase III Orbit and Cosmic Studies for setrusumab, claiming it would reduce fracture rates in Osteogenesis Imperfecta patients [2]. - The complaint asserts that Ultragenyx provided overly positive statements while concealing material adverse facts about setrusumab's potential and the risks associated with the study protocols, particularly that increased bone density did not correlate with reduced fracture rates [3]. Group 2: Study Results and Stock Impact - On December 29, 2025, Ultragenyx announced that its Phase III studies did not achieve statistical significance in reducing annualized clinical fracture rates compared to placebo or bisphosphonates, attributing the failure to a low fracture rate in the placebo group [4]. - Following this announcement, Ultragenyx's stock price plummeted from $34.19 per share on December 26, 2025, to $19.72 per share on December 29, 2025, marking a decline of approximately 42.32% in one day [4].

Core Viewpoint - A class action securities lawsuit has been filed against Ultragenyx Pharmaceutical Inc. for alleged securities fraud affecting investors between August 3, 2023, and December 26, 2025 [1] Group 1 - The lawsuit is initiated by Kahn Swick & Foti, LLC and its partner, former Attorney General of Louisiana, Charles C. Foti, Jr. [1] - The action seeks to recover losses for investors adversely affected by the alleged fraud [1]

Core Viewpoint - RARE investors are presented with an opportunity to lead a securities fraud lawsuit against Ultragenyx Pharmaceutical Inc. in collaboration with the Schall Law Firm [1] Group 1 - The lawsuit is focused on allegations of securities fraud involving Ultragenyx Pharmaceutical Inc. [1] - The Schall Law Firm is actively seeking investors who have suffered losses to participate in the lawsuit [1] - This legal action may provide a platform for investors to seek restitution for their financial losses related to the company's alleged misconduct [1]

Core Viewpoint - Ultragenyx Pharmaceutical Inc. will host a conference call on February 12, 2026, to discuss its financial results and corporate updates for the year ending December 31, 2025 [1]. Group 1: Company Overview - Ultragenyx is a biopharmaceutical company focused on developing and commercializing novel products for serious rare and ultra-rare genetic diseases [3]. - The company has established a diverse portfolio of approved therapies and product candidates aimed at addressing diseases with high unmet medical needs [3]. - Ultragenyx's management team has extensive experience in the development and commercialization of therapeutics for rare diseases [4]. Group 2: Strategic Approach - The company's strategy emphasizes time- and cost-efficient drug development to deliver safe and effective therapies to patients urgently [4].

Faruqi & Faruqi, LLP Securities Litigation Partner James (Josh) Wilson Encourages Investors Who Suffered Losses In Ultragenyx To Contact Him Directly To Discuss Their Options If you purchased or acquired securities in Ultragenyx between August 3, 2023 and December 26, 2025 and would like to discuss your legal rights, call Faruqi & Faruqi partner Josh Wilson directly at 877-247-4292 or 212-983-9330 (Ext. 1310). [You may also click here for additional information] NEW YORK, Feb. 05, 2026 (GLOBE NEWSWIRE) -- ...

NEW YORK--(BUSINESS WIRE)--Rosen Law Firm, a global investor rights law firm, announces a class action lawsuit on behalf of purchasers of common stock of Ultragenyx Pharmaceutical Inc. (NASDAQ: RARE) between August 3, 2023 and December 26, 2025. Ultragenyx describes itself as a "biopharmaceutical company focused on rare and ultrarare genetic disorders.†For more information, submit a form, email attorney Phillip Kim, or give us a call at 866-767-3653. The Allegations: Rosen Law Firm is Investig. ...

NEW YORK, Feb. 05, 2026 (GLOBE NEWSWIRE) -- Gainey McKenna & Egleston announces that a securities class action lawsuit has been filed in the United States District Court for the Northern District of California on behalf of all persons or entities who purchased or otherwise acquired Ultragenyx Pharmaceutical Inc. (“Ultragenyx” or the “Company”) (NASDAQ: RARE) securities between August 3, 2023 and December 26, 2025, inclusive (the “Class Period”). The Complaint alleges that Defendants provided misleading stat ...