Law Offices of Howard G. Smith announces that a class action lawsuit has been filed on behalf of investors who purchased MoonLake Immunotherapeutics (“MoonLake” or the “Company”) (NASDAQ: MLTX) common stock between March 10, 2024 and September 29, 2025, inclusive (the “Class Period”). MoonLake investors have until December 15, 2025 to file a lead plaintiff motion.

IF YOU ARE AN INVESTOR WHO SUFFERED A LOSS IN MOONLAKE IMMUNOTHERAPEUTICS (MLTX), CONTACT THE LAW OFFICES OF HOWARD G. SMITH TO PARTICIPATE IN THE ONGOING SECURITIES FRAUD LAWSUIT.

Contact the Law Offices of Howard G. Smith to discuss your legal rights by email at howardsmith@howardsmithlaw.com, by telephone at (215) 638-4847 or visit our website at www.howardsmithlaw.com.

What Happened?

On September 28, 2025, MoonLake Immunotherapeutics announced disappointing Phase 3 results for its only drug candidate, sonelokimab (“SLK”), revealing that SLK failed to match the efficacy of its competitor, Union Chimique Belge’s bimekizumab-bkz (“BIMZELX”). The Company had repeatedly promoted SLK’s nanobody structure as superior to other monoclonal antibodies—while allegedly failing to disclose it targeted the same molecules and lacked proven advantages.

Following the news, MoonLake’s stock fell $55.74, or 89.9%, to close at $6.24 per share on September 29, 2025, and thereby harming investors.

What Is The Lawsuit About?

The complaint filed in this class action alleges that throughout the Class Period, Defendants made materially false and/or misleading statements, as well as failed to disclose material adverse facts about the Company’s business, operations, and prospects. Specifically, Defendants failed to disclose to investors that: (1) that SLK and BIMZELX share the same molecular targets (the inflammatory cytokines IL-17A and IL-17F); (2) that SLK’s distinct Nanobody structure would not confer a superior clinical benefit over the traditional monoclonal structure of BIMZELX; (3) SLK’s distinct Nanobody structure supposed increased tissue penetration would not translate to clinical efficacy; and (4) as a result, Defendants’ positive statements about the Company’s business, operations, and prospects were materially misleading and/or lacked a reasonable basis at all relevant times.

Contact Us To Participate or Learn More:

If you purchased MoonLake common stock, have information or would like to learn more about these claims, or have any questions concerning this announcement or your rights or interests with respect to these matters, please contact us:

Law Offices of Howard G. Smith,

3070 Bristol Pike, Suite 112,

Bensalem, Pennsylvania 19020,

Telephone: (215) 638-4847

Email: howardsmith@howardsmithlaw.com,

Visit our website at: www.howardsmithlaw.com.

This press release may be considered Attorney Advertising in some jurisdictions under the applicable law and ethical rules.

View source version on businesswire.com: https://www.businesswire.com/news/home/20251024908106/en/