MoonLake Immunotherapeutics (MLTX) Faces Securities Class Action After Company Reported Disastrous Phase 3 Trial Data For Sole Drug Candidate -- Hagens Berman

Core Viewpoint - MoonLake Immunotherapeutics faces a securities class action lawsuit following the announcement of disappointing Phase 3 trial results for its product candidate sonelokimab (SLK), leading to a significant drop in share price by approximately 90% [1][2][6]. Company Overview - MoonLake Immunotherapeutics is a clinical-stage biotechnology company focused on treating skin inflammatory diseases, specifically targeting cytokines IL-17A and IL-17F [3][4]. Legal Proceedings - A class action lawsuit has been filed against MoonLake, alleging that the company misled investors regarding the trial design and efficacy data of SLK prior to the announcement of the trial results [1][2][3]. - The class period for the lawsuit is from March 10, 2024, to September 29, 2025, with a lead plaintiff deadline set for December 15, 2025 [3]. Trial Results and Market Reaction - The Phase 3 trial results revealed that only one of the two trials achieved statistical significance, with the efficacy being substantially lower than that of a competitor's product, BIMZELX [6]. - Following the announcement, MoonLake's share price plummeted by $55.75, representing a 90% decrease, which analysts described as a "worst case outcome" [2][6]. Product Comparison - SLK's commercial prospects were heavily reliant on demonstrating efficacy comparable to or superior to BIMZELX, which is already FDA-approved for the same indication [4]. - The lawsuit claims that MoonLake made false statements regarding the advantages of SLK's Nanobody structure over traditional monoclonal antibodies, asserting that it would lead to superior clinical benefits [5]. Investor Communication - Throughout the class period, MoonLake promoted SLK's structural advantages, claiming it could achieve benefits unattainable by monoclonal antibodies and positioned it as a potential "gold standard" treatment [5]. - The lawsuit alleges that these statements were misleading and that the company failed to disclose critical information about SLK's clinical efficacy [5][6].