The Law Offices of Frank R. Cruz announces that a class action lawsuit has been filed on behalf of shareholders 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 SUFFERED A LOSS ON YOUR MOONLAKE IMMUNOTHERAPEUTICS (MLTX) INVESTMENTS, CLICK HERE TO SUBMIT A CLAIM TO POTENTIALLY RECOVER YOUR LOSSES IN THE ONGOING SECURITIES FRAUD LAWSUIT.

You can also contact the Law Offices of Frank R. Cruz to discuss your legal rights by email at info@frankcruzlaw.com, by telephone at (310) 914-5007, or visit our website at www.frankcruzlaw.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, wish to learn more about this action, or have any questions concerning this announcement or your rights or interests with respect to these matters, please click HERE or contact us at:

Law Offices of Frank R. Cruz

2121 Avenue of the Stars, Suite 800

Telephone: 310-914-5007

Email: info@frankcruzlaw.com

Visit our website at: www.frankcruzlaw.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/20251028417881/en/

Law Offices of Frank R. Cruz Encourages MoonLake Immunotherapeutics (MLTX) Shareholders To Inquire About Securities Fraud Class Action