A class action lawsuit has been filed against Moonlake Immunotherapeutics on behalf of investors who suffered losses between March 10, 2024 and September 29, 2025. The complaint alleges that the company made false or misleading statements regarding its sole drug candidate, SLK. Specifically, it is claimed that Moonlake concealed that SLK and another drug, BIMZELX, share the same molecular targets, and that SLK's unique Nanobody structure would not provide superior clinical benefits or increased tissue penetration compared to traditional monoclonal antibodies. Based on these factors, the lawsuit argues that the company lacked a reasonable basis for its positive statements about SLK's purported advantages. The litigation seeks to recover losses for affected shareholders.