Ultragenyx Investors Investigated for Securities Fraud and Unlawful Practices.

Pomerantz LLP is investigating claims on behalf of investors of Ultragenyx Pharmaceutical Inc. regarding potential securities fraud or unlawful business practices. The investigation concerns the Company's Phase 3 study of UX143 for osteogenesis imperfecta, which is progressing toward a final analysis expected by the end of the year. Investors are advised to contact Danielle Peyton at newaction@pomlaw.com or 646-581-9980, ext. 7980.

New York, Aug. 11, 2025 — Pomerantz LLP has initiated an investigation into claims on behalf of investors of Ultragenyx Pharmaceutical Inc. (NASDAQ: RARE). The investigation focuses on whether Ultragenyx and certain of its officers and/or directors have engaged in securities fraud or other unlawful business practices [1].

The investigation is prompted by recent developments in Ultragenyx's Phase 3 clinical trial of UX143, a drug candidate for osteogenesis imperfecta (OI). On July 9, 2025, the company and its development partner Mereo BioPharma Group plc announced that the randomized, placebo-controlled Phase 3 portion of the Orbit study is progressing toward a final analysis expected by the end of the year. Following this announcement, Ultragenyx's stock price fell by $10.41 per share, or 25.11%, to close at $31.04 on July 10, 2025 [2].

Investors are advised to contact Danielle Peyton at newaction@pomlaw.com or 646-581-9980, ext. 7980, for more information about the investigation.

Pomerantz LLP, with offices in New York, Chicago, Los Angeles, London, and Paris, is recognized for its expertise in corporate, securities, and antitrust class litigation. The firm has a history of recovering multimillion-dollar damages for class members in securities fraud cases [1].

References:
[1] https://www.marketscreener.com/news/pomerantz-law-firm-investigates-claims-on-behalf-of-investors-of-ultragenyx-pharmaceutical-inc-ra-ce7c5ed2d18cf520
[2] https://www.bakersfield.com/ap/news/investor-alert-pomerantz-law-firm-investigates-claims-on-behalf-of-investors-of-ultragenyx/article_52d5f5b2-8791-526e-a076-b4c868d96c33.html