Ultragenyx Pharmaceutical Class Action Lawsuit Notification
Written by Emily J. Thompson, Senior Investment Analyst
Updated: 1 hour ago
0mins
Should l Buy RARE?
Source: Globenewswire
- Lawsuit Background: Kahn Swick & Foti LLC informs investors of a class action lawsuit against Ultragenyx Pharmaceutical for alleged securities fraud occurring between August 3, 2023, and December 26, 2025, aimed at recovering losses for affected investors.
- Study Failure Impact: On December 26, 2025, Ultragenyx announced that its Phase 3 Orbit and Cosmic studies for setrusumab failed to show a statistically significant reduction in annualized fracture rates for osteogenesis imperfecta patients, prompting the company to evaluate significant expense reductions.
- Stock Price Plunge: Following the lawsuit announcement, Ultragenyx's stock price plummeted approximately 42%, from $34.19 per share on December 26, 2025, to $19.72 per share on December 29, 2025, indicating a pessimistic market outlook on the company's future.
- Investor Action Recommendation: Affected investors have until April 6, 2026, to request to be appointed as lead plaintiff, although they can still share in any recovery without serving as lead plaintiff, highlighting the legal process's potential impact on investors.
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Analyst Views on RARE
Wall Street analysts forecast RARE stock price to rise
18 Analyst Rating
17 Buy
1 Hold
0 Sell
Strong Buy
Current: 22.610
Low
35.00
Averages
61.65
High
120.00
Current: 22.610
Low
35.00
Averages
61.65
High
120.00
About RARE
Ultragenyx Pharmaceutical Inc. is a biopharmaceutical company. The Company is focused on the identification, acquisition, development, and commercialization of novel products for the treatment of serious rare and ultrarare genetic diseases. Its therapies and clinical-stage pipeline consist of four product categories: biologics, small molecules, AAV gene therapy, and nucleic acid product candidates. Its four approved product candidates include Crysvita (burosumab) for the treatment of X-linked hypophosphatemia (XLH), and tumor-induced osteomalacia (TIO), Mepsevii (vestronidase alfa) for the treatment of mucopolysaccharidosis VII (MPSVII) or Sly Syndrome, Dojolvi (triheptanoin) for the treatment of long-chain fatty acid oxidation disorders (LC-FAOD), and Evkeeza (evinacumab) for the treatment of homozygous familial hypercholesterolemia (HoFH). Its clinical product candidates include DTX401, DTX301, UX701, UX143, UX111, and GTX-102. UX143 for the treatment of Osteogenesis Imperfecta.
About the author
Emily J. Thompson
Emily J. Thompson, a Chartered Financial Analyst (CFA) with 12 years in investment research, graduated with honors from the Wharton School. Specializing in industrial and technology stocks, she provides in-depth analysis for Intellectia’s earnings and market brief reports.
Ultragenyx Pharmaceutical Class Action Lawsuit Notification
- Lawsuit Background: Kahn Swick & Foti LLC informs investors of a class action lawsuit against Ultragenyx Pharmaceutical for alleged securities fraud occurring between August 3, 2023, and December 26, 2025, aimed at recovering losses for affected investors.
- Study Failure Impact: On December 26, 2025, Ultragenyx announced that its Phase 3 Orbit and Cosmic studies for setrusumab failed to show a statistically significant reduction in annualized fracture rates for osteogenesis imperfecta patients, prompting the company to evaluate significant expense reductions.
- Stock Price Plunge: Following the lawsuit announcement, Ultragenyx's stock price plummeted approximately 42%, from $34.19 per share on December 26, 2025, to $19.72 per share on December 29, 2025, indicating a pessimistic market outlook on the company's future.
- Investor Action Recommendation: Affected investors have until April 6, 2026, to request to be appointed as lead plaintiff, although they can still share in any recovery without serving as lead plaintiff, highlighting the legal process's potential impact on investors.
See More
Ultragenyx Faces Class Action Lawsuit Amid Significant Stock Decline
- Class Action Filed: Pomerantz LLP has initiated a class action lawsuit against Ultragenyx Pharmaceutical, alleging securities fraud and unlawful business practices by the company and certain officers, with investors needing to apply as Lead Plaintiff by April 6, 2026.
- Stock Price Plunge: Following disappointing clinical trial updates on July 10, 2025, Ultragenyx's stock fell by 25.11%, losing $10.41 per share to close at $31.04, reflecting significant market concerns regarding its developmental prospects.
- Trial Failures Announced: On December 29, 2025, Ultragenyx disclosed that its Phase III Orbit and Cosmic studies failed to achieve statistical significance, causing a further 42.32% drop in stock price, equating to a $14.47 loss per share, closing at $34.19, which heightened investor anxiety.
- Potential Legal Ramifications: The class action lawsuit could expose Ultragenyx to substantial financial liabilities, impacting its future fundraising capabilities and market credibility, posing significant challenges to the company's long-term growth trajectory.
See More
Ultragenyx Pharmaceutical Class Action Notice
- Class Action Deadline: Ultragenyx Pharmaceutical Inc. (NASDAQ:RARE) reminds stock purchasers from August 3, 2023, to December 26, 2025, that the lead plaintiff deadline is April 6, 2026, and failure to act may result in loss of participation rights.
- Fee Arrangement: Investors joining the class action can seek compensation without upfront costs through a contingency fee arrangement, which alleviates financial burdens and encourages affected shareholders to participate in the litigation.
- Lawsuit Background: The lawsuit alleges that Ultragenyx misled investors regarding the expected results of its studies for Osteogenesis Imperfecta, providing overly optimistic projections while concealing critical adverse information, leading shareholders to purchase stock at inflated prices.
- Counsel Selection: The Rosen Law Firm emphasizes the importance of selecting qualified counsel with a proven track record, noting that many firms issuing notices lack the necessary litigation experience and resources, urging investors to choose their representatives wisely.
See More
Ultragenyx Pharmaceutical Class Action Reminder
- Class Action Notice: Rosen Law Firm reminds investors who purchased Ultragenyx Pharmaceutical (NASDAQ: RARE) common stock between August 3, 2023, and December 26, 2025, to apply as lead plaintiffs by April 6, 2026, to potentially receive compensation without any out-of-pocket costs.
- Lawsuit Background: The lawsuit alleges that defendants misled investors regarding the efficacy of setrusumab (UX 143) in treating Osteogenesis Imperfecta (OI) by concealing adverse information, resulting in shareholders purchasing stock at artificially inflated prices and suffering losses when the truth emerged.
- Law Firm Credentials: Rosen Law Firm specializes in securities class actions and has recovered over $438 million for investors in 2019 alone, being ranked first by ISS Securities Class Action Services in 2017, highlighting its strong track record and expertise in this area.
- Investor Action Advice: Investors can visit Rosen Law Firm's website or call the toll-free number for more information, ensuring they select qualified legal counsel to represent them effectively in the lawsuit and avoid inexperienced intermediaries.
See More
Ultragenyx Faces Class Action Over Misleading Drug Information
- Class Action Notification: The Portnoy Law Firm advises Ultragenyx Pharmaceutical investors of a class action for those who purchased securities between August 3, 2023, and December 26, 2025, with a deadline for lead plaintiff motions set for April 6, 2026, highlighting the urgency for affected investors to act.
- False Statement Allegations: The lawsuit alleges that Ultragenyx misled investors regarding the efficacy of its drug setrusumab, failing to disclose risks that patients in the Phase III Orbit study might not achieve a statistically significant reduction in annualized fracture rate, which misrepresented the company's prospects and misled investment decisions.
- Clinical Trial Risks: Ultragenyx's failure to adequately communicate the risks associated with relying on Phase II results without a placebo control group raises concerns about the validity of their optimistic claims regarding the drug's effectiveness, potentially undermining investor confidence in the company's operations.
- Legal Consultation Services: The Portnoy Law Firm offers complimentary case evaluations and encourages investors to reach out to discuss their legal options for recovering losses, demonstrating the firm's commitment to protecting investor rights and providing support in the face of corporate misconduct.
See More
Ultragenyx and Mereo BioPharma Class Action Reminder
- Lawsuit Initiation: Bragar Eagel & Squire law firm has commenced class actions on behalf of shareholders of Ultragenyx Pharmaceutical (NASDAQ:RARE) and Mereo BioPharma (NASDAQ:MREO), with a lead plaintiff deadline of April 6, 2026, indicating significant investor concern regarding potential risks associated with these companies.
- Study Result Failures: On December 29, 2025, Ultragenyx announced that its Phase III Orbit and Cosmic studies failed to achieve statistical significance in reducing annualized fracture rates, causing its stock price to plummet by approximately 42.32% in a single day, from $34.19 to $19.72, reflecting market disappointment in the study outcomes.
- Mereo BioPharma's Reaction: Similarly, Mereo BioPharma announced on December 29, 2025, that its ORBIT and COSMIC studies did not meet the primary endpoint of reducing annualized clinical fracture rates, despite improved bone mineral density, leading to a dramatic decline in its ADS price from $2.31 to $0.29, a drop of over 87.7%, highlighting severe investor confidence erosion.
- Disclosure Issues: The lawsuits allege that both companies provided overly optimistic projections to investors while concealing significant adverse facts related to the study protocols, resulting in shareholders purchasing stocks at artificially inflated prices, raising concerns about corporate governance and transparency.
See More
Ultragenyx Pharmaceutical Class Action Lawsuit Notification
- Lawsuit Background: Kahn Swick & Foti LLC informs investors of a class action lawsuit against Ultragenyx Pharmaceutical for alleged securities fraud occurring between August 3, 2023, and December 26, 2025, aimed at recovering losses for affected investors.
- Study Failure Impact: On December 26, 2025, Ultragenyx announced that its Phase 3 Orbit and Cosmic studies for setrusumab failed to show a statistically significant reduction in annualized fracture rates for osteogenesis imperfecta patients, prompting the company to evaluate significant expense reductions.
- Stock Price Plunge: Following the lawsuit announcement, Ultragenyx's stock price plummeted approximately 42%, from $34.19 per share on December 26, 2025, to $19.72 per share on December 29, 2025, indicating a pessimistic market outlook on the company's future.
- Investor Action Recommendation: Affected investors have until April 6, 2026, to request to be appointed as lead plaintiff, although they can still share in any recovery without serving as lead plaintiff, highlighting the legal process's potential impact on investors.
See More
Ultragenyx Faces Class Action Lawsuit Amid Significant Stock Decline
- Class Action Filed: Pomerantz LLP has initiated a class action lawsuit against Ultragenyx Pharmaceutical, alleging securities fraud and unlawful business practices by the company and certain officers, with investors needing to apply as Lead Plaintiff by April 6, 2026.
- Stock Price Plunge: Following disappointing clinical trial updates on July 10, 2025, Ultragenyx's stock fell by 25.11%, losing $10.41 per share to close at $31.04, reflecting significant market concerns regarding its developmental prospects.
- Trial Failures Announced: On December 29, 2025, Ultragenyx disclosed that its Phase III Orbit and Cosmic studies failed to achieve statistical significance, causing a further 42.32% drop in stock price, equating to a $14.47 loss per share, closing at $34.19, which heightened investor anxiety.
- Potential Legal Ramifications: The class action lawsuit could expose Ultragenyx to substantial financial liabilities, impacting its future fundraising capabilities and market credibility, posing significant challenges to the company's long-term growth trajectory.
See More
Ultragenyx Pharmaceutical Class Action Notice
- Class Action Deadline: Ultragenyx Pharmaceutical Inc. (NASDAQ:RARE) reminds stock purchasers from August 3, 2023, to December 26, 2025, that the lead plaintiff deadline is April 6, 2026, and failure to act may result in loss of participation rights.
- Fee Arrangement: Investors joining the class action can seek compensation without upfront costs through a contingency fee arrangement, which alleviates financial burdens and encourages affected shareholders to participate in the litigation.
- Lawsuit Background: The lawsuit alleges that Ultragenyx misled investors regarding the expected results of its studies for Osteogenesis Imperfecta, providing overly optimistic projections while concealing critical adverse information, leading shareholders to purchase stock at inflated prices.
- Counsel Selection: The Rosen Law Firm emphasizes the importance of selecting qualified counsel with a proven track record, noting that many firms issuing notices lack the necessary litigation experience and resources, urging investors to choose their representatives wisely.
See More
Ultragenyx Pharmaceutical Class Action Reminder
- Class Action Notice: Rosen Law Firm reminds investors who purchased Ultragenyx Pharmaceutical (NASDAQ: RARE) common stock between August 3, 2023, and December 26, 2025, to apply as lead plaintiffs by April 6, 2026, to potentially receive compensation without any out-of-pocket costs.
- Lawsuit Background: The lawsuit alleges that defendants misled investors regarding the efficacy of setrusumab (UX 143) in treating Osteogenesis Imperfecta (OI) by concealing adverse information, resulting in shareholders purchasing stock at artificially inflated prices and suffering losses when the truth emerged.
- Law Firm Credentials: Rosen Law Firm specializes in securities class actions and has recovered over $438 million for investors in 2019 alone, being ranked first by ISS Securities Class Action Services in 2017, highlighting its strong track record and expertise in this area.
- Investor Action Advice: Investors can visit Rosen Law Firm's website or call the toll-free number for more information, ensuring they select qualified legal counsel to represent them effectively in the lawsuit and avoid inexperienced intermediaries.
See More
Ultragenyx Faces Class Action Over Misleading Drug Information
- Class Action Notification: The Portnoy Law Firm advises Ultragenyx Pharmaceutical investors of a class action for those who purchased securities between August 3, 2023, and December 26, 2025, with a deadline for lead plaintiff motions set for April 6, 2026, highlighting the urgency for affected investors to act.
- False Statement Allegations: The lawsuit alleges that Ultragenyx misled investors regarding the efficacy of its drug setrusumab, failing to disclose risks that patients in the Phase III Orbit study might not achieve a statistically significant reduction in annualized fracture rate, which misrepresented the company's prospects and misled investment decisions.
- Clinical Trial Risks: Ultragenyx's failure to adequately communicate the risks associated with relying on Phase II results without a placebo control group raises concerns about the validity of their optimistic claims regarding the drug's effectiveness, potentially undermining investor confidence in the company's operations.
- Legal Consultation Services: The Portnoy Law Firm offers complimentary case evaluations and encourages investors to reach out to discuss their legal options for recovering losses, demonstrating the firm's commitment to protecting investor rights and providing support in the face of corporate misconduct.
See More
Ultragenyx and Mereo BioPharma Class Action Reminder
- Lawsuit Initiation: Bragar Eagel & Squire law firm has commenced class actions on behalf of shareholders of Ultragenyx Pharmaceutical (NASDAQ:RARE) and Mereo BioPharma (NASDAQ:MREO), with a lead plaintiff deadline of April 6, 2026, indicating significant investor concern regarding potential risks associated with these companies.
- Study Result Failures: On December 29, 2025, Ultragenyx announced that its Phase III Orbit and Cosmic studies failed to achieve statistical significance in reducing annualized fracture rates, causing its stock price to plummet by approximately 42.32% in a single day, from $34.19 to $19.72, reflecting market disappointment in the study outcomes.
- Mereo BioPharma's Reaction: Similarly, Mereo BioPharma announced on December 29, 2025, that its ORBIT and COSMIC studies did not meet the primary endpoint of reducing annualized clinical fracture rates, despite improved bone mineral density, leading to a dramatic decline in its ADS price from $2.31 to $0.29, a drop of over 87.7%, highlighting severe investor confidence erosion.
- Disclosure Issues: The lawsuits allege that both companies provided overly optimistic projections to investors while concealing significant adverse facts related to the study protocols, resulting in shareholders purchasing stocks at artificially inflated prices, raising concerns about corporate governance and transparency.
See More
