Ultragenyx Faces Class Action Lawsuit
Written by Emily J. Thompson, Senior Investment Analyst
Updated: Mar 23 2026
0mins
Should l Buy RARE?
Source: Globenewswire
- Class Action Initiation: Robbins Geller law firm announces that purchasers of Ultragenyx Pharmaceutical Inc. (NASDAQ: RARE) common stock between August 3, 2023, and December 26, 2025, can seek lead plaintiff status in a class action lawsuit, indicating significant investor distrust in the company's management.
- False Statement Allegations: The lawsuit alleges that Ultragenyx and its executives made false and misleading statements throughout the class period, failing to disclose risks associated with the Phase III Orbit study, which misled investors about the company's prospects and negatively impacted stock prices.
- Stock Price Plunge: Following the July 9, 2025 announcement that the Phase III Orbit study failed to achieve statistical significance, Ultragenyx's stock price fell over 25%; the subsequent announcement on December 29, 2025, of further study failures led to an additional drop of over 42%, reflecting extreme market pessimism regarding the company's future.
- Investor Rights Protection: Under the Private Securities Litigation Reform Act of 1995, any investor who purchased Ultragenyx stock during the class period can seek lead plaintiff status, emphasizing the importance of protecting investor rights and ensuring accountability from corporate management.
Trade with 70% Backtested Accuracy
Stop guessing "Should I Buy RARE?" and start using high-conviction signals backed by rigorous historical data.
Sign up today to access powerful investing tools and make smarter, data-driven decisions.
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: 19.380
Low
35.00
Averages
61.65
High
120.00
Current: 19.380
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 Notice Issued
- Class Action Notice: Rosen Law Firm reminds investors who purchased Ultragenyx (NASDAQ:RARE) common stock between August 3, 2023, and December 26, 2025, to apply as lead plaintiffs by April 6, 2026, to participate in the class action and seek compensation.
- Lawsuit Background: The lawsuit alleges that defendants provided false and misleading information regarding setrusumab's (UX 143) efficacy in reducing annual fracture rates in Osteogenesis Imperfecta patients during Phase III Orbit and Cosmic studies, leading investors to purchase shares at inflated prices.
- Legal Representation Choice: Investors are encouraged to select experienced legal counsel, with Rosen Law Firm recognized for its successful track record in securities class actions, having recovered over $438 million for investors in 2019 alone.
- Potential Impact: If the lawsuit is successful, Ultragenyx shareholders may receive compensation; however, until the class is certified, investors must choose their legal representation, and those opting out may still share in any future recovery.
See More
Ultragenyx Pharmaceutical Class Action Notice Issued
- Class Action Initiation: Rosen Law Firm reminds investors who purchased Ultragenyx Pharmaceutical Inc. (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 Ultragenyx provided overly optimistic expectations regarding its clinical trials for Osteogenesis Imperfecta, claiming that setrusumab would significantly reduce fracture rates, which was not supported by actual results.
- Investor Losses: The defendants are accused of misleading investors by disseminating positive statements while concealing critical risks associated with setrusumab, leading to inflated stock purchases and subsequent losses when the truth emerged.
- Law Firm's Credentials: Rosen Law Firm specializes in securities class actions, having recovered over $438 million for investors in 2019 alone, and was ranked first in 2017 for the number of securities class action settlements, showcasing its extensive experience and success in this field.
See More
FDA Approves Ultragenyx's UX016 for GNE Myopathy
- New Drug Approval: The US FDA has cleared Ultragenyx Pharmaceutical (RARE) for its Investigational New Drug application for UX016, aimed at treating the rare inherited neuromuscular disorder GNE myopathy, marking a significant advancement for the company in the rare disease sector.
- Innovative Treatment Mechanism: UX016, as a prodrug of sialic acid, offers a substrate replacement therapy targeting the condition characterized by insufficient sialic acid production, indicating a potential new treatment option that could enhance patient quality of life.
- Clinical Trial Plans: A phase 1/2 study for the drug is slated to commence in the second half of 2026, which is expected to provide critical data for further validating its safety and efficacy, thereby facilitating future market access.
- Broad Market Potential: With the FDA's approval, Ultragenyx's market potential in the rare disease space significantly increases, likely attracting more investor interest and laying the groundwork for future product line expansions.
See More
Class Action Lawsuit Reminder Against Ultragenyx Pharmaceutical Inc.
- Class Action Notice: The Schall Law Firm reminds investors of a class action lawsuit against Ultragenyx Pharmaceutical Inc. (NASDAQ:RARE) for violations of securities laws related to securities transactions between August 3, 2023, and December 26, 2025.
- False Statements Exposed: The complaint alleges that Ultragenyx made false and misleading statements regarding its understanding of the effects of its drug candidate on patients with Osteogenesis Imperfecta (OI), leading to an overly optimistic outlook among investors.
- Study Results Impact: The Phase III ORBIT study revealed that Ultragenyx failed to achieve a statistically significant reduction in annualized fracture rate (AFR), highlighting significant errors in the company's clinical trials and resulting in investor losses.
- Legal Consultation Opportunity: Investors are encouraged to contact the Schall Law Firm before April 6, 2026, to discuss their rights and participate in the lawsuit to seek compensation for their losses.
See More
Ultragenyx Receives FDA Clearance for UX016 Clinical Trial
- FDA Approval for Clinical Trial: Ultragenyx announced that the IND application for UX016 has been cleared by the FDA, marking a significant step towards clinical evaluation for GNE myopathy, with a Phase 1/2 study expected to begin in the second half of 2026, offering new hope for patients.
- Innovative Drug Design: UX016 is an investigational small molecule prodrug that combines sialic acid with a C16 fatty acid tail, designed to enhance biodistribution to muscle, potentially overcoming limitations of previous therapies and improving patient quality of life.
- Impact on Patient Population: GNE myopathy affects approximately 10,000 patients with no approved treatment options currently available; the clinical trial for UX016 will provide a crucial therapeutic avenue for this rare disease, potentially transforming their lives.
- External Funding Support: The program is externally funded by a patient group, reflecting the community's trust and support for Ultragenyx, which is expected to facilitate the smooth progress of the clinical study and drive the development of innovative therapies.
See More
Class Action Lawsuit Reminder Against Ultragenyx Pharmaceutical Inc.
- Lawsuit Background: DJS Law Group reminds investors of a class action lawsuit against Ultragenyx Pharmaceutical for violations of securities laws, affecting shareholders from August 3, 2023, to December 26, 2025, with a deadline of April 6, 2026.
- False Statements: The complaint alleges that Ultragenyx made false and misleading statements regarding its Phase III trial performance, creating overly optimistic expectations despite failing to meet statistically significant endpoints, misleading investors throughout the class period.
- Investor Losses: Affected shareholders are encouraged to contact DJS Law Group to participate in the recovery process, indicating that the company may face significant financial liabilities, which could undermine shareholder confidence and market performance.
- Legal Services: DJS Law Group specializes in securities class actions and corporate governance litigation, aiming to assist clients in recovering losses through aggressive legal advocacy, showcasing its expertise and influence in complex legal matters.
See More
Ultragenyx Pharmaceutical Class Action Notice Issued
- Class Action Notice: Rosen Law Firm reminds investors who purchased Ultragenyx (NASDAQ:RARE) common stock between August 3, 2023, and December 26, 2025, to apply as lead plaintiffs by April 6, 2026, to participate in the class action and seek compensation.
- Lawsuit Background: The lawsuit alleges that defendants provided false and misleading information regarding setrusumab's (UX 143) efficacy in reducing annual fracture rates in Osteogenesis Imperfecta patients during Phase III Orbit and Cosmic studies, leading investors to purchase shares at inflated prices.
- Legal Representation Choice: Investors are encouraged to select experienced legal counsel, with Rosen Law Firm recognized for its successful track record in securities class actions, having recovered over $438 million for investors in 2019 alone.
- Potential Impact: If the lawsuit is successful, Ultragenyx shareholders may receive compensation; however, until the class is certified, investors must choose their legal representation, and those opting out may still share in any future recovery.
See More
Ultragenyx Pharmaceutical Class Action Notice Issued
- Class Action Initiation: Rosen Law Firm reminds investors who purchased Ultragenyx Pharmaceutical Inc. (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 Ultragenyx provided overly optimistic expectations regarding its clinical trials for Osteogenesis Imperfecta, claiming that setrusumab would significantly reduce fracture rates, which was not supported by actual results.
- Investor Losses: The defendants are accused of misleading investors by disseminating positive statements while concealing critical risks associated with setrusumab, leading to inflated stock purchases and subsequent losses when the truth emerged.
- Law Firm's Credentials: Rosen Law Firm specializes in securities class actions, having recovered over $438 million for investors in 2019 alone, and was ranked first in 2017 for the number of securities class action settlements, showcasing its extensive experience and success in this field.
See More
FDA Approves Ultragenyx's UX016 for GNE Myopathy
- New Drug Approval: The US FDA has cleared Ultragenyx Pharmaceutical (RARE) for its Investigational New Drug application for UX016, aimed at treating the rare inherited neuromuscular disorder GNE myopathy, marking a significant advancement for the company in the rare disease sector.
- Innovative Treatment Mechanism: UX016, as a prodrug of sialic acid, offers a substrate replacement therapy targeting the condition characterized by insufficient sialic acid production, indicating a potential new treatment option that could enhance patient quality of life.
- Clinical Trial Plans: A phase 1/2 study for the drug is slated to commence in the second half of 2026, which is expected to provide critical data for further validating its safety and efficacy, thereby facilitating future market access.
- Broad Market Potential: With the FDA's approval, Ultragenyx's market potential in the rare disease space significantly increases, likely attracting more investor interest and laying the groundwork for future product line expansions.
See More
Class Action Lawsuit Reminder Against Ultragenyx Pharmaceutical Inc.
- Class Action Notice: The Schall Law Firm reminds investors of a class action lawsuit against Ultragenyx Pharmaceutical Inc. (NASDAQ:RARE) for violations of securities laws related to securities transactions between August 3, 2023, and December 26, 2025.
- False Statements Exposed: The complaint alleges that Ultragenyx made false and misleading statements regarding its understanding of the effects of its drug candidate on patients with Osteogenesis Imperfecta (OI), leading to an overly optimistic outlook among investors.
- Study Results Impact: The Phase III ORBIT study revealed that Ultragenyx failed to achieve a statistically significant reduction in annualized fracture rate (AFR), highlighting significant errors in the company's clinical trials and resulting in investor losses.
- Legal Consultation Opportunity: Investors are encouraged to contact the Schall Law Firm before April 6, 2026, to discuss their rights and participate in the lawsuit to seek compensation for their losses.
See More
Ultragenyx Receives FDA Clearance for UX016 Clinical Trial
- FDA Approval for Clinical Trial: Ultragenyx announced that the IND application for UX016 has been cleared by the FDA, marking a significant step towards clinical evaluation for GNE myopathy, with a Phase 1/2 study expected to begin in the second half of 2026, offering new hope for patients.
- Innovative Drug Design: UX016 is an investigational small molecule prodrug that combines sialic acid with a C16 fatty acid tail, designed to enhance biodistribution to muscle, potentially overcoming limitations of previous therapies and improving patient quality of life.
- Impact on Patient Population: GNE myopathy affects approximately 10,000 patients with no approved treatment options currently available; the clinical trial for UX016 will provide a crucial therapeutic avenue for this rare disease, potentially transforming their lives.
- External Funding Support: The program is externally funded by a patient group, reflecting the community's trust and support for Ultragenyx, which is expected to facilitate the smooth progress of the clinical study and drive the development of innovative therapies.
See More
Class Action Lawsuit Reminder Against Ultragenyx Pharmaceutical Inc.
- Lawsuit Background: DJS Law Group reminds investors of a class action lawsuit against Ultragenyx Pharmaceutical for violations of securities laws, affecting shareholders from August 3, 2023, to December 26, 2025, with a deadline of April 6, 2026.
- False Statements: The complaint alleges that Ultragenyx made false and misleading statements regarding its Phase III trial performance, creating overly optimistic expectations despite failing to meet statistically significant endpoints, misleading investors throughout the class period.
- Investor Losses: Affected shareholders are encouraged to contact DJS Law Group to participate in the recovery process, indicating that the company may face significant financial liabilities, which could undermine shareholder confidence and market performance.
- Legal Services: DJS Law Group specializes in securities class actions and corporate governance litigation, aiming to assist clients in recovering losses through aggressive legal advocacy, showcasing its expertise and influence in complex legal matters.
See More
