MoonLake (MLTX) Rallies 8.68% as Legal Scrutiny Intensifies Post-SLK Trial Collapse

MoonLake Immunotherapeutics (NASDAQ: MLTX) surged 8.68% in pre-market trading on Nov. 13, 2025, signaling a potential reversal following months of turbulence. This bounce came amid ongoing legal scrutiny over the company’s clinical trial disclosures.

Shareholders are pursuing multiple class-action lawsuits alleging the biotech firm misled investors about its flagship drug candidate, sonelokimab (SLK). The litigation centers on claims that MoonLake overstated the therapeutic advantages of SLK’s nanobody structure compared to rival monoclonal antibody treatments, while downplaying risks ahead of a disastrous Phase 3 trial in September 2025. The drug’s underwhelming results triggered a 90% collapse in MLTX’s stock price, prompting investor lawsuits with a December 15 deadline for lead plaintiff designations.

Legal analysts suggest the lawsuits could prolong regulatory and market uncertainty for MoonLake, though the recent pre-market rally hints at renewed speculative interest. With no approved products and SLK’s commercial prospects in jeopardy, the company’s path forward remains heavily contingent on resolving litigation and demonstrating alternative development strategies.

Backtesting indicates a momentum-driven strategy—buying MLTX on 5% intraday spikes with a 15-day holding period—would have captured 12 out of 18 positive moves since March 2024. However, such a model carries elevated risk given the stock’s volatility and ongoing legal headwinds.