MoonLake Investors Face Critical Deadline Following 90% Share Value Collapse

2025-12-14 companies

New York, Saturday, 13 December 2025.
MoonLake investors face a December 15 deadline to join a class action lawsuit after failed technology claims triggered a catastrophic 90% stock collapse, wiping out nearly all value overnight.

Imminent Legal Deadline for Shareholders

With the December 15, 2025, Lead Plaintiff Deadline just two days away, legal pressure is mounting on MoonLake Immunotherapeutics (MLTX) [1][2]. Global plaintiffs’ rights firms, including Hagens Berman and Bronstein, Gewirtz & Grossman, LLC, are actively mobilizing investors following allegations that the biotechnology firm issued misleading financial statements regarding its flagship technology [1][4]. The litigation centers on a dramatic market correction that occurred in late September, which fundamentally altered the company’s valuation [2].

Anatomy of a 90% Market Crash

The financial impact on shareholders was immediate and severe. On September 29, 2025, MoonLake’s stock price collapsed from $61.99 to just $6.24, representing a decline of -89.934 percent in a single trading session [1][2]. This massive sell-off was triggered by the release of disappointing results from the Phase 3 VELA-2 trial, which failed to meet its primary endpoint [2]. As of December 12, 2025, the company’s market capitalization stands at $1.05 billion, with the stock trading significantly below its 52-week high of $62.75 [3].

Scrutiny of Nanobody Superiority Claims

At the heart of the class action lawsuit is the company’s promotion of sonelokimab (SLK), a Nanobody technology. Plaintiffs allege that MoonLake executives made false statements concerning SLK’s clinical prospects, specifically touting its “superiority” over conventional monoclonal antibody treatments such as BIMZELX [2][7]. Hagens Berman partner Reed Kathrein noted that these promises “evaporated” upon the release of the trial data, leaving investors with substantial losses as the perceived technological advantage failed to materialize in the clinical setting [1][7].

Timeline and Investor Recourse

The defined class period for this litigation spans from March 10, 2024, through September 29, 2025 [4]. Investors who purchased shares during this window and suffered damages have until the December 15, 2025, deadline to request lead plaintiff status [1][8]. In addition to shareholder actions, legal firms are encouraging whistleblowers with non-public information regarding the company’s operations to come forward, highlighting the potential for rewards totaling up to 30 percent of successful SEC recoveries [1][7].

Financial Outlook Amidst Litigation

As the window for legal action narrows, the MoonLake case serves as a stark reminder of the volatility inherent in the biotechnology sector, particularly regarding late-stage clinical trials. With earnings per share for Q3 2025 reported at -$1.10—missing estimates by over 20 percent—and the next earnings report not expected until February 2026, the focus for investors currently remains on the unfolding legal proceedings [3].

Sources

Class Action Biotech