Ultragenyx Pharmaceutical(US:RARE) Globenewswire·2026-03-21 12:00Core Viewpoint - Rosen Law Firm is reminding investors who purchased common stock of Ultragenyx Pharmaceutical Inc. during the specified class period of the upcoming lead plaintiff deadline for a class action lawsuit [1]. Group 1: Class Action Details - Investors who bought Ultragenyx common stock between August 3, 2023, and December 26, 2025, may be eligible for compensation without any out-of-pocket fees through a contingency fee arrangement [2]. - A class action lawsuit has already been filed, and interested parties must move the Court to serve as lead plaintiff by April 6, 2026 [3]. - The Rosen Law Firm emphasizes the importance of selecting qualified legal counsel with a successful track record in securities class actions [4]. Group 2: Case Background - The lawsuit alleges that Ultragenyx's defendants provided misleading information regarding the expected results of their Phase III Orbit and Cosmic Studies for setrusumab (UX 143) in treating Osteogenesis Imperfecta [5]. - It is claimed that the defendants made overly positive statements about setrusumab's efficacy while concealing material adverse facts, leading to inflated stock prices for Ultragenyx [6].