Ultragenyx Faces Class Action Over Misleading Drug Claims
Written by Emily J. Thompson, Senior Investment Analyst
Updated: 1 hour ago
0mins
Should l Buy RARE?
Source: Globenewswire
- Class Action Initiated: The Portnoy Law Firm has filed a class action against Ultragenyx Pharmaceutical on behalf of investors who purchased securities between August 3, 2023, and December 26, 2025, with a deadline for lead plaintiff motions set for April 6, 2026, indicating potential legal liabilities for the company.
- Allegations of Misleading Statements: The lawsuit alleges that Ultragenyx misrepresented the reliability of data regarding 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 could mislead investors about the company's prospects and affect stock performance.
- Investor Rights Protection: The Portnoy Law Firm offers complimentary case evaluations and encourages investors to contact attorneys to discuss their legal rights, demonstrating support for affected investors and potentially increasing participation in the lawsuit.
- Historical Compensation Record: The firm's founding partner has recovered over $5.5 billion for aggrieved investors, showcasing a successful track record in similar cases, which may enhance investor confidence in the ongoing litigation.
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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: 20.450
Low
35.00
Averages
61.65
High
120.00
Current: 20.450
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: Ultragenyx Pharmaceutical Inc. is facing a class action lawsuit for securities violations during the period from August 3, 2023, to December 26, 2025, with investors needing to apply as lead plaintiffs by April 6, 2026, indicating significant legal risks for the company.
- Stock Price Plunge: Following the announcements on July 9, 2025, and December 29, 2025, Ultragenyx's stock fell over 25% and 42%, respectively, due to the failure to achieve statistical significance in clinical trials, reflecting a severe loss of market confidence in its research capabilities.
- Details of Allegations: The lawsuit alleges that Ultragenyx misled investors by failing to disclose risks associated with its clinical trials, creating false expectations about its products, which could lead to substantial financial losses for investors.
- Law Firm Background: Robbins Geller Rudman & Dowd LLP, one of the world's leading class action firms, recovered over $916 million for investors in 2025, showcasing its strong capabilities and influence in securities fraud litigation.
See More
Ultragenyx Faces Class Action Over Misleading Drug Claims
- Class Action Initiated: The Portnoy Law Firm has filed a class action against Ultragenyx Pharmaceutical on behalf of investors who purchased securities between August 3, 2023, and December 26, 2025, with a deadline for lead plaintiff motions set for April 6, 2026, indicating potential legal liabilities for the company.
- Allegations of Misleading Statements: The lawsuit alleges that Ultragenyx misrepresented the reliability of data regarding 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 could mislead investors about the company's prospects and affect stock performance.
- Investor Rights Protection: The Portnoy Law Firm offers complimentary case evaluations and encourages investors to contact attorneys to discuss their legal rights, demonstrating support for affected investors and potentially increasing participation in the lawsuit.
- Historical Compensation Record: The firm's founding partner has recovered over $5.5 billion for aggrieved investors, showcasing a successful track record in similar cases, which may enhance investor confidence in the ongoing litigation.
See More
Ultragenyx Pharmaceutical Shareholder Notice Issued
- Shareholder Notice: The Gross Law Firm has issued a notice to shareholders of Ultragenyx Pharmaceutical Inc., encouraging those who purchased shares during the class period from August 3, 2023, to December 26, 2025, to contact the firm for potential lead plaintiff appointment, indicating the company may face legal liabilities.
- False Statements Allegations: The complaint alleges that Ultragenyx provided overwhelmingly positive statements while concealing significant adverse facts regarding setrusumab's risks in clinical trials, which could lead to investor losses due to misleading information.
- Study Failure Impact: On December 29, 2025, Ultragenyx announced that its Phase III Orbit and Cosmic studies failed to achieve statistical significance in reducing annualized fracture rates, resulting in a dramatic stock price drop of approximately 42.32%, from $34.19 per share to $19.72 per share in just one day.
- Legal Action Deadline: Shareholders must register by April 6, 2026, to participate in the class action lawsuit, and failure to register in time may result in the loss of the right to claim, highlighting the urgency of the company's legal responsibilities.
See More
Ultragenyx Securities Class Action Reminder
- Filing Deadline: ClaimsFiler reminds investors that those who purchased Ultragenyx shares between August 3, 2023, and December 26, 2025, must file lead plaintiff applications by April 6, 2026, to participate in the securities class action lawsuit, as failing to do so may result in the loss of compensation opportunities.
- Stock Price Plunge: Following the December 26, 2025 announcement that Ultragenyx's setrusumab (UX143) failed to show a statistically significant reduction in fracture rates in its Phase III studies, the stock price plummeted by approximately 42%, from $34.19 to $19.72, indicating severe market pessimism regarding the company's future prospects.
- Legal Allegations: The lawsuit alleges that Ultragenyx and certain executives failed to disclose material information during the class period, violating federal securities laws, which could expose the company to significant legal and financial risks, thereby affecting investor confidence and future operations.
- Cost Reduction Plans: Ultragenyx stated it would evaluate its operational plans and promptly implement significant expense reductions in response to the stock price drop, a strategy that may impact its ongoing R&D and marketing efforts while attempting to stabilize its financial situation.
See More
Ultragenyx Pharmaceutical Faces Securities Fraud Class Action Lawsuit
- Lawsuit Background: Kessler Topaz Meltzer & Check, LLP has filed a securities fraud class action against Ultragenyx Pharmaceutical, involving investors who purchased stock between August 3, 2023, and December 26, 2025, highlighting serious concerns over the company's transparency.
- False Statements Allegations: The lawsuit alleges that Ultragenyx made misleading statements regarding the efficacy of its drug setrusumab in the Phase III Orbit study, failing to disclose the risk that patients might not achieve a statistically significant reduction in annualized fracture rate, potentially leading to misjudgments about the company's prospects.
- Investor Action: Affected investors must apply for lead plaintiff status by April 6, 2026, to represent all impacted investors in the litigation, indicating a proactive stance and engagement from the investor community in legal proceedings.
- Law Firm's Role: Kessler Topaz Meltzer & Check, LLP is a leading law firm focused on securities fraud class actions, representing both individual and institutional investors, underscoring its significance in safeguarding investor rights.
See More
Ultragenyx Pharmaceutical Class Action Notice Issued
- Shareholder Lawsuit Notice: The Gross Law Firm has issued a notice to shareholders of Ultragenyx Pharmaceutical Inc. (NASDAQ: RARE), encouraging those who purchased shares during the class period from August 3, 2023, to December 26, 2025, to contact the firm regarding potential lead plaintiff appointment for recovery participation.
- False Statements Allegations: The complaint alleges that Ultragenyx provided overwhelmingly positive statements while concealing significant adverse facts about setrusumab's potential, misleading investors and impacting their decision-making regarding the company's future.
- Clinical Trial Failure: On December 29, 2025, Ultragenyx announced that its Phase III Orbit and Cosmic studies failed to achieve statistical significance on primary endpoints, resulting in a dramatic stock price drop of approximately 42.32% in one day, from $34.19 to $19.72, severely undermining investor confidence.
- Claim Deadline: Shareholders must register by April 6, 2026, to participate in the class action lawsuit, and upon registration, they will receive status updates throughout the case lifecycle, ensuring their rights are protected during the legal proceedings.
See More
Ultragenyx Faces Class Action Lawsuit Over Securities Violations
- Class Action Initiation: Ultragenyx Pharmaceutical Inc. is facing a class action lawsuit for securities violations during the period from August 3, 2023, to December 26, 2025, with investors needing to apply as lead plaintiffs by April 6, 2026, indicating significant legal risks for the company.
- Stock Price Plunge: Following the announcements on July 9, 2025, and December 29, 2025, Ultragenyx's stock fell over 25% and 42%, respectively, due to the failure to achieve statistical significance in clinical trials, reflecting a severe loss of market confidence in its research capabilities.
- Details of Allegations: The lawsuit alleges that Ultragenyx misled investors by failing to disclose risks associated with its clinical trials, creating false expectations about its products, which could lead to substantial financial losses for investors.
- Law Firm Background: Robbins Geller Rudman & Dowd LLP, one of the world's leading class action firms, recovered over $916 million for investors in 2025, showcasing its strong capabilities and influence in securities fraud litigation.
See More
Ultragenyx Faces Class Action Over Misleading Drug Claims
- Class Action Initiated: The Portnoy Law Firm has filed a class action against Ultragenyx Pharmaceutical on behalf of investors who purchased securities between August 3, 2023, and December 26, 2025, with a deadline for lead plaintiff motions set for April 6, 2026, indicating potential legal liabilities for the company.
- Allegations of Misleading Statements: The lawsuit alleges that Ultragenyx misrepresented the reliability of data regarding 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 could mislead investors about the company's prospects and affect stock performance.
- Investor Rights Protection: The Portnoy Law Firm offers complimentary case evaluations and encourages investors to contact attorneys to discuss their legal rights, demonstrating support for affected investors and potentially increasing participation in the lawsuit.
- Historical Compensation Record: The firm's founding partner has recovered over $5.5 billion for aggrieved investors, showcasing a successful track record in similar cases, which may enhance investor confidence in the ongoing litigation.
See More
Ultragenyx Pharmaceutical Shareholder Notice Issued
- Shareholder Notice: The Gross Law Firm has issued a notice to shareholders of Ultragenyx Pharmaceutical Inc., encouraging those who purchased shares during the class period from August 3, 2023, to December 26, 2025, to contact the firm for potential lead plaintiff appointment, indicating the company may face legal liabilities.
- False Statements Allegations: The complaint alleges that Ultragenyx provided overwhelmingly positive statements while concealing significant adverse facts regarding setrusumab's risks in clinical trials, which could lead to investor losses due to misleading information.
- Study Failure Impact: On December 29, 2025, Ultragenyx announced that its Phase III Orbit and Cosmic studies failed to achieve statistical significance in reducing annualized fracture rates, resulting in a dramatic stock price drop of approximately 42.32%, from $34.19 per share to $19.72 per share in just one day.
- Legal Action Deadline: Shareholders must register by April 6, 2026, to participate in the class action lawsuit, and failure to register in time may result in the loss of the right to claim, highlighting the urgency of the company's legal responsibilities.
See More
Ultragenyx Securities Class Action Reminder
- Filing Deadline: ClaimsFiler reminds investors that those who purchased Ultragenyx shares between August 3, 2023, and December 26, 2025, must file lead plaintiff applications by April 6, 2026, to participate in the securities class action lawsuit, as failing to do so may result in the loss of compensation opportunities.
- Stock Price Plunge: Following the December 26, 2025 announcement that Ultragenyx's setrusumab (UX143) failed to show a statistically significant reduction in fracture rates in its Phase III studies, the stock price plummeted by approximately 42%, from $34.19 to $19.72, indicating severe market pessimism regarding the company's future prospects.
- Legal Allegations: The lawsuit alleges that Ultragenyx and certain executives failed to disclose material information during the class period, violating federal securities laws, which could expose the company to significant legal and financial risks, thereby affecting investor confidence and future operations.
- Cost Reduction Plans: Ultragenyx stated it would evaluate its operational plans and promptly implement significant expense reductions in response to the stock price drop, a strategy that may impact its ongoing R&D and marketing efforts while attempting to stabilize its financial situation.
See More
Ultragenyx Pharmaceutical Faces Securities Fraud Class Action Lawsuit
- Lawsuit Background: Kessler Topaz Meltzer & Check, LLP has filed a securities fraud class action against Ultragenyx Pharmaceutical, involving investors who purchased stock between August 3, 2023, and December 26, 2025, highlighting serious concerns over the company's transparency.
- False Statements Allegations: The lawsuit alleges that Ultragenyx made misleading statements regarding the efficacy of its drug setrusumab in the Phase III Orbit study, failing to disclose the risk that patients might not achieve a statistically significant reduction in annualized fracture rate, potentially leading to misjudgments about the company's prospects.
- Investor Action: Affected investors must apply for lead plaintiff status by April 6, 2026, to represent all impacted investors in the litigation, indicating a proactive stance and engagement from the investor community in legal proceedings.
- Law Firm's Role: Kessler Topaz Meltzer & Check, LLP is a leading law firm focused on securities fraud class actions, representing both individual and institutional investors, underscoring its significance in safeguarding investor rights.
See More
Ultragenyx Pharmaceutical Class Action Notice Issued
- Shareholder Lawsuit Notice: The Gross Law Firm has issued a notice to shareholders of Ultragenyx Pharmaceutical Inc. (NASDAQ: RARE), encouraging those who purchased shares during the class period from August 3, 2023, to December 26, 2025, to contact the firm regarding potential lead plaintiff appointment for recovery participation.
- False Statements Allegations: The complaint alleges that Ultragenyx provided overwhelmingly positive statements while concealing significant adverse facts about setrusumab's potential, misleading investors and impacting their decision-making regarding the company's future.
- Clinical Trial Failure: On December 29, 2025, Ultragenyx announced that its Phase III Orbit and Cosmic studies failed to achieve statistical significance on primary endpoints, resulting in a dramatic stock price drop of approximately 42.32% in one day, from $34.19 to $19.72, severely undermining investor confidence.
- Claim Deadline: Shareholders must register by April 6, 2026, to participate in the class action lawsuit, and upon registration, they will receive status updates throughout the case lifecycle, ensuring their rights are protected during the legal proceedings.
See More
