MoonLake (MLTX) Class Action Lawsuit – Hagens Berman Scrutinizing Nanobody Superiority Claims After 90% Plunge; December Lead Plaintiff Deadline Looms

Global plaintiffs' rights firm Hagens Berman reminds investors that the Lead Plaintiff Deadline in the securities class action lawsuit against MoonLake Immunotherapeutics (NASDAQ: MLTX) is rapidly approaching: December 15, 2025.

The lawsuit alleges that MoonLake and certain executives made materially false and misleading statements regarding the clinical prospects of the company’s lead and sole drug candidate, sonelokimab (SLK), causing the stock to crash nearly 90% on the revelation of disappointing Phase 3 trial results. Hagens Berman urges investors with significant losses to submit their losses now.

The Lawsuit’s Core Allegation: The Nanobody Deception

The lawsuit focuses on the company’s repeated claims that SLK’s distinctive Nanobody structure would translate into superior clinical efficacy (like higher HiSCR75 responses) compared to conventional monoclonal antibody treatments, specifically the FDA-approved competitor BIMZELX.

“We are focusing on the repeated assurances MoonLake gave investors about the supposed 'superiority' of their Nanobody technology. When the VELA-2 results came out, those promises evaporated, and investors lost nearly everything overnight,” said Reed Kathrein, the Hagens Berman partner leading the litigation. “As the December 15 deadline approaches, we encourage investors who suffered heavy losses to contact the firm to discuss their rights.”

Timeline and Key Details:

Issuer	MoonLake Immunotherapeutics (MLTX)
Class Period	March 10, 2024 – September 29, 2025
Lead Plaintiff Deadline	December 15, 2025
Stock Drop Event	Stock fell from $61.99 to $6.24 (a 90% loss) on September 29, 2025, after VELA-2 trial failed its primary endpoint and efficacy was shown to be inferior to a competitor.

Next Steps for MoonLake (MLTX) Investors:

Investors who purchased MoonLake stock (MLTX) between March 10, 2024, and September 29, 2025, and suffered substantial losses, are encouraged to contact Hagens Berman immediately to discuss their legal options and potential appointment as Lead Plaintiff.

TO SUBMIT YOUR MOONLAKE (MLTX) STOCK LOSSES AND DISCUSS THE NANOBODY EFFICACY ALLEGATIONS, PLEASE USE THE SECURE FORM BELOW:

• Submit your MoonLake (MLTX) losses now
• Visit MLTX Case Page: www.hbsslaw.com/cases/mltx

Contact Partner Reed Kathrein:

• Email [e-mail]
• Call: 844-916-0895

Whistleblowers: Persons with non-public information regarding MoonLake should consider their options to help in the investigation or take advantage of the SEC Whistleblower program. Under the new program, whistleblowers who provide original information may receive rewards totaling up to 30 percent of any successful recovery made by the SEC. For more information, call Reed Kathrein at 844-916-0895 or email [e-mail].

About Hagens Berman

Hagens Berman is a global plaintiffs’ rights complex litigation firm focusing on corporate accountability. The firm is home to a robust practice and represents investors as well as whistleblowers, workers, consumers and others in cases achieving real results for those harmed by corporate negligence and other wrongdoings. Hagens Berman’s team has secured more than $2.9 billion in this area of law. More about the firm and its successes can be found at hbsslaw.com. Follow the firm for updates and news at @ClassActionLaw.

View source version on businesswire.com: https://www.businesswire.com/news/home/20251210608850/en/

The MoonLake Immunotherapeutics Registered (A) Stock at the time of publication of the news with a fall of -0,14 % to 14,53USD on Nasdaq stock exchange (10. Dezember 2025, 15:40 Uhr).