Investors Alert: Class Action Lawsuit Filed Against MoonLake Immunotherapeutics Amid Securities Fraud Allegations

In a significant legal action, the renowned law firm Berger Montague PC has initiated a class action lawsuit against MoonLake Immunotherapeutics (NASDAQ: MLTX). This lawsuit concerns investors who acquired shares of MoonLake during the period of March 10, 2024, through September 29, 2025, commonly referred to as the Class Period. The deadline for affected investors to act is fast approaching, with December 15, 2025, set as the cutoff for those looking to serve as lead plaintiff representatives in this case.

MoonLake Immunotherapeutics, based in Zug, Switzerland, is a biopharmaceutical company focusing on innovative therapies for inflammatory diseases. The lawsuit arises from allegations that the company misled its investors regarding the clinical capabilities of its primary drug candidate, sonelokimab (SLK). According to the allegations, MoonLake aggressively promoted SLK as being superior to competing therapies based on its unique Nanobody structure; however, this assertion is under scrutiny.

The crux of the problem lies in the claim that MoonLake failed to disclose critical information—that SLK targets similar molecules as the FDA-approved treatment BIMZELX. This oversight was purportedly significant enough to impact investors' decision-making processes profoundly.

On September 28, 2025, the company released Phase 3 clinical trial results that showed SLK did not perform as well as BIMZELX. The results were described by analysts as “disastrous,” causing MoonLake's stock to plummet by a staggering $55.75 per share, representing a nearly 90% loss in value in a single trading day. This drastic decrease has raised alarms among investors looking to comprehend the potential implications of these developments.

Berger Montague has not only become a key player in this litigation but is also encouraging other MoonLake investors to step forward to understand their legal rights and explore their options in the wake of these allegations. “If you have purchased MoonLake securities during the Class Period and wish to know more about how to protect your interests, we urge you to reach out,” stated Andrew Abramowitz, a senior counsel at the firm.

This situation highlights the importance of transparency and ethics within the biopharmaceutical industry, particularly as it pertains to investor relations and the communication of clinical trial data. The implications of this lawsuit could be far-reaching, not only for MoonLake and its shareholders but also for the broader market landscape where biotech firms operate under close scrutiny.

Given the rapid developments surrounding this case, it is advisable for current or prospective investors to stay informed about the lawsuit's progression, participate actively if they are eligible, and consult with legal professionals who specialize in securities fraud.

As legal proceedings unfold, Berger Montague remains committed to advocating for the rights of investors potentially harmed by misleading practices. Investors are encouraged to gather all relevant documentation and be proactive in safeguarding their interests as this case proceeds through the judicial system.

For those interested in pursuing this matter further or needing assistance, they can contact Berger Montague directly. The firm has a long-standing reputation for handling complex civil litigations and class actions, boasting over six decades of experience and recovering substantial sums for their clients. Therefore, seeking legal counsel could be a critical step for affected investors.

In summation, the MoonLake Immunotherapeutics securities fraud lawsuit is a crucial development in the healthcare and investment sectors. Investors are urged to take timely action in light of the timeline for filing claims and to ensure their rights are upheld throughout this process.