Class Action Filed Against Ultragenyx Pharmaceutical Inc.
Written by Emily J. Thompson, Senior Investment Analyst
Updated: Feb 06 2026
0mins
Should l Buy RARE?
Source: PRnewswire
- Lawsuit Background: National plaintiffs' law firm Berger Montague PC has announced a class action lawsuit against Ultragenyx Pharmaceutical Inc. on behalf of investors who purchased stock between August 3, 2023, and December 26, 2025, indicating a significant loss of investor confidence in the company's future prospects.
- Stock Price Plunge: Following the disclosure on December 29, 2025, that Ultragenyx's ORBIT and COSMIC Phase 3 trials failed to meet their primary endpoints, the stock price plummeted over 42%, from $34.19 per share on December 26, 2025, to $19.72 per share, reflecting a pessimistic outlook from the market regarding the company's future.
- Investor Rights: Investors must apply by April 6, 2026, to be appointed as lead plaintiff representatives in the class action, highlighting concerns over corporate governance and information disclosure that may influence future investment decisions.
- Law Firm's Strength: Berger Montague, a leading law firm specializing in complex civil litigation and class actions, has recovered over $50 billion for clients over the past 55 years, showcasing its significant strength and influence in the legal field.
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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: 22.070
Low
35.00
Averages
61.65
High
120.00
Current: 22.070
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 Faces Class Action Lawsuit Over Securities Violations
- Class Action Initiation: Robbins Geller Rudman & Dowd LLP announces that investors who purchased Ultragenyx Pharmaceutical Inc. stock between August 3, 2023, and December 26, 2025, can seek lead plaintiff status in a class action lawsuit, indicating strong investor concern over potential violations.
- Stock Price Plunge: Following the July 9, 2025, announcement that the Phase III Orbit study failed to achieve statistical significance, Ultragenyx's stock fell over 25%, and after the December 29, 2025, revelation of further study failures, the stock dropped more than 42%, reflecting a pessimistic market outlook.
- False Statement Allegations: The lawsuit alleges that Ultragenyx and its executives made false or misleading statements during the class period, failing to disclose risks associated with Osteogenesis Imperfecta studies, which may have misled investors and impacted future financing capabilities.
- Legal Process Overview: Under the Private Securities Litigation Reform Act of 1995, any investor who purchased Ultragenyx stock during the class period can apply to be the lead plaintiff, representing other investors in the lawsuit, highlighting the legal mechanisms in place to protect investor rights.
See More
Ultragenyx Pharmaceutical Accused of Misleading Investors in Class Action
- Class Action Initiated: Robbins LLP reminds investors of a class action filed on behalf of shareholders who purchased Ultragenyx Pharmaceutical Inc. (NASDAQ: RARE) stock between August 3, 2023, and December 26, 2025, alleging the company misled investors regarding clinical trial results.
- Study Results Failure: On December 29, 2025, Ultragenyx announced that its Phase III Orbit and Cosmic studies did not achieve statistical significance on primary endpoints, causing the stock price to plummet approximately 42.32% in a single day, from $34.19 to $19.72, severely impacting investor confidence.
- Misleading Statements: The lawsuit alleges that Ultragenyx made overly optimistic statements about setrusumab's potential while concealing the lack of correlation between increased bone density and reduced fracture rates, leading investors to purchase shares at artificially inflated prices.
- Shareholder Action Recommended: Affected shareholders are encouraged to contact Robbins LLP to participate in the class action as lead plaintiffs, representing other shareholders in the litigation without incurring any fees, demonstrating the firm's commitment to shareholder rights.
See More
Class Action Lawsuit Filed Against Ultragenyx Pharmaceutical Inc.
- Lawsuit Background: Bronstein, Gewirtz & Grossman, LLC, a nationally recognized investor-rights law firm, has filed a class action lawsuit against Ultragenyx Pharmaceutical Inc. and certain officers, seeking damages for investors who purchased securities between August 3, 2023, and December 26, 2025.
- Allegations: The complaint alleges that throughout the class period, defendants made false and/or misleading statements and failed to disclose risks associated with the Phase III Orbit study's results, misleading investors about the treatment's efficacy for Osteogenesis Imperfecta patients.
- Investor Action: Affected investors are encouraged to apply to be lead plaintiffs by April 6, 2026, to share in any potential recovery, with the assurance that participation does not require serving as lead plaintiff.
- Law Firm's Reputation: Bronstein, Gewirtz & Grossman, LLC has a strong reputation in securities fraud class actions, having recovered hundreds of millions for investors nationwide, emphasizing their commitment to restoring investor capital and ensuring corporate accountability.
See More
Ultragenyx Pharmaceuticals Faces Investor Lawsuit Over Securities Violations
- Investor Loss Warning: Faruqi & Faruqi LLP is investigating potential securities litigation against Ultragenyx Pharmaceuticals, urging investors who purchased securities between August 3, 2023, and December 26, 2025, to apply for lead plaintiff status by April 6, 2026, indicating significant legal risks for the company.
- Study Result Failures: Ultragenyx revealed on July 9, 2025, that its Phase III Orbit study failed to achieve statistical significance, causing a stock price drop of over 25%, and subsequently announced on December 29, 2025, that both Orbit and Cosmic studies did not meet primary endpoints, leading to an additional 42% decline, reflecting severe investor confidence erosion.
- False Statement Allegations: The lawsuit alleges that Ultragenyx and its executives violated federal securities laws by making false or misleading statements regarding study results, failing to disclose associated risks, which may mislead investors in their decision-making and impact their returns.
- Legal Consultation Opportunity: Faruqi & Faruqi encourages anyone with information, including former employees and shareholders, to contact the firm, highlighting the company's lack of transparency regarding legal issues, which could affect its future market performance and investor trust.
See More
Ultragenyx Pharmaceutical Securities Lawsuit Notification
- Lawsuit Background: Kahn Swick & Foti LLC informs investors in Ultragenyx Pharmaceutical of a class action lawsuit due to 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 studies for setrusumab (UX143) 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 announcement, Ultragenyx's stock price fell approximately 42%, from $34.19 per share on December 26, 2025, to $19.72 per share on December 29, 2025, indicating a negative 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 in that role, highlighting ongoing opportunities for legal recourse for investors seeking compensation.
See More
FDA Faces Criticism Amid Innovation Challenges
- Regulatory Standards Controversy: Congressman Jake Auchincloss criticized FDA Commissioner Marty Makary for replacing standards of safety and efficacy with fear and favoritism, undermining patient confidence in new therapies and impacting the market launch of innovative drugs.
- Staffing Losses: The FDA has experienced significant staff reductions in its Center for Drug Evaluation and Research, with oncology review staff dropping from about 100 to below 60, which may lead to approval delays and incomplete response letters.
- Decline in Accelerated Approvals: In 2024, the FDA approved 20 drugs through the accelerated approval process, down from 9 the previous year, indicating a direct impact on drug approval efficiency due to the loss of experienced reviewers.
- New Therapy Approval Pathways: The FDA proposed a new system for approving personalized drugs aimed at rare diseases, intending to provide more flexible approval pathways, but this change has sparked widespread controversy, affecting the agency's core mission.
See More
Ultragenyx Faces Class Action Lawsuit Over Securities Violations
- Class Action Initiation: Robbins Geller Rudman & Dowd LLP announces that investors who purchased Ultragenyx Pharmaceutical Inc. stock between August 3, 2023, and December 26, 2025, can seek lead plaintiff status in a class action lawsuit, indicating strong investor concern over potential violations.
- Stock Price Plunge: Following the July 9, 2025, announcement that the Phase III Orbit study failed to achieve statistical significance, Ultragenyx's stock fell over 25%, and after the December 29, 2025, revelation of further study failures, the stock dropped more than 42%, reflecting a pessimistic market outlook.
- False Statement Allegations: The lawsuit alleges that Ultragenyx and its executives made false or misleading statements during the class period, failing to disclose risks associated with Osteogenesis Imperfecta studies, which may have misled investors and impacted future financing capabilities.
- Legal Process Overview: Under the Private Securities Litigation Reform Act of 1995, any investor who purchased Ultragenyx stock during the class period can apply to be the lead plaintiff, representing other investors in the lawsuit, highlighting the legal mechanisms in place to protect investor rights.
See More
Ultragenyx Pharmaceutical Accused of Misleading Investors in Class Action
- Class Action Initiated: Robbins LLP reminds investors of a class action filed on behalf of shareholders who purchased Ultragenyx Pharmaceutical Inc. (NASDAQ: RARE) stock between August 3, 2023, and December 26, 2025, alleging the company misled investors regarding clinical trial results.
- Study Results Failure: On December 29, 2025, Ultragenyx announced that its Phase III Orbit and Cosmic studies did not achieve statistical significance on primary endpoints, causing the stock price to plummet approximately 42.32% in a single day, from $34.19 to $19.72, severely impacting investor confidence.
- Misleading Statements: The lawsuit alleges that Ultragenyx made overly optimistic statements about setrusumab's potential while concealing the lack of correlation between increased bone density and reduced fracture rates, leading investors to purchase shares at artificially inflated prices.
- Shareholder Action Recommended: Affected shareholders are encouraged to contact Robbins LLP to participate in the class action as lead plaintiffs, representing other shareholders in the litigation without incurring any fees, demonstrating the firm's commitment to shareholder rights.
See More
Class Action Lawsuit Filed Against Ultragenyx Pharmaceutical Inc.
- Lawsuit Background: Bronstein, Gewirtz & Grossman, LLC, a nationally recognized investor-rights law firm, has filed a class action lawsuit against Ultragenyx Pharmaceutical Inc. and certain officers, seeking damages for investors who purchased securities between August 3, 2023, and December 26, 2025.
- Allegations: The complaint alleges that throughout the class period, defendants made false and/or misleading statements and failed to disclose risks associated with the Phase III Orbit study's results, misleading investors about the treatment's efficacy for Osteogenesis Imperfecta patients.
- Investor Action: Affected investors are encouraged to apply to be lead plaintiffs by April 6, 2026, to share in any potential recovery, with the assurance that participation does not require serving as lead plaintiff.
- Law Firm's Reputation: Bronstein, Gewirtz & Grossman, LLC has a strong reputation in securities fraud class actions, having recovered hundreds of millions for investors nationwide, emphasizing their commitment to restoring investor capital and ensuring corporate accountability.
See More
Ultragenyx Pharmaceuticals Faces Investor Lawsuit Over Securities Violations
- Investor Loss Warning: Faruqi & Faruqi LLP is investigating potential securities litigation against Ultragenyx Pharmaceuticals, urging investors who purchased securities between August 3, 2023, and December 26, 2025, to apply for lead plaintiff status by April 6, 2026, indicating significant legal risks for the company.
- Study Result Failures: Ultragenyx revealed on July 9, 2025, that its Phase III Orbit study failed to achieve statistical significance, causing a stock price drop of over 25%, and subsequently announced on December 29, 2025, that both Orbit and Cosmic studies did not meet primary endpoints, leading to an additional 42% decline, reflecting severe investor confidence erosion.
- False Statement Allegations: The lawsuit alleges that Ultragenyx and its executives violated federal securities laws by making false or misleading statements regarding study results, failing to disclose associated risks, which may mislead investors in their decision-making and impact their returns.
- Legal Consultation Opportunity: Faruqi & Faruqi encourages anyone with information, including former employees and shareholders, to contact the firm, highlighting the company's lack of transparency regarding legal issues, which could affect its future market performance and investor trust.
See More
Ultragenyx Pharmaceutical Securities Lawsuit Notification
- Lawsuit Background: Kahn Swick & Foti LLC informs investors in Ultragenyx Pharmaceutical of a class action lawsuit due to 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 studies for setrusumab (UX143) 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 announcement, Ultragenyx's stock price fell approximately 42%, from $34.19 per share on December 26, 2025, to $19.72 per share on December 29, 2025, indicating a negative 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 in that role, highlighting ongoing opportunities for legal recourse for investors seeking compensation.
See More
FDA Faces Criticism Amid Innovation Challenges
- Regulatory Standards Controversy: Congressman Jake Auchincloss criticized FDA Commissioner Marty Makary for replacing standards of safety and efficacy with fear and favoritism, undermining patient confidence in new therapies and impacting the market launch of innovative drugs.
- Staffing Losses: The FDA has experienced significant staff reductions in its Center for Drug Evaluation and Research, with oncology review staff dropping from about 100 to below 60, which may lead to approval delays and incomplete response letters.
- Decline in Accelerated Approvals: In 2024, the FDA approved 20 drugs through the accelerated approval process, down from 9 the previous year, indicating a direct impact on drug approval efficiency due to the loss of experienced reviewers.
- New Therapy Approval Pathways: The FDA proposed a new system for approving personalized drugs aimed at rare diseases, intending to provide more flexible approval pathways, but this change has sparked widespread controversy, affecting the agency's core mission.
See More
