#Phase 3 Trials #MoonLake #sonelokimab

Legal Action Looms Over MoonLake Immunotherapeutics

MoonLake Immunotherapeutics, recognized by its stock symbol MLTX, has found itself at the center of a class action lawsuit titled Bridgewood v. MoonLake Immunotherapeutics et al., filed in the U.S. District Court for the Southern District of New York. This legal action arises after the company reported dismal results from a Phase 3 clinical trial concerning its sole drug candidate, sonelokimab (SLK), intended to treat a painful skin ailment known as hidradenitis suppurativa (HS).

Disastrous Trial Data

On September 28, 2025, MoonLake announced the disappointing results of its Phase 3 trial, which sent shockwaves through the market. Investors watching the performance of MLTX shares witnessed a staggering decline of approximately 90%, losing $55.75 in value almost overnight. The announcement triggered extensive investigations led by Hagens Berman, a well-known national shareholder rights law firm, which is now scrutinizing whether MoonLake misled its investors regarding the trial's design and the prospective efficacy of SLK.

The crux of the lawsuit suggests that prior to the disastrous announcement, MoonLake may have provided investors with a misleading portrayal of SLK’s clinical trial, including its design and intended outcomes. Allegations have emerged that the company oversold the potential effectiveness of its drug, promising advantages that were not substantiated in the trial results.

The Competitor and Its Significance

SLK was anticipated to provide substantial competition to BIMZELX, an FDA-approved drug for the same condition that also targets the IL-17A and IL-17F cytokines involved in HS. MoonLake had positioned SLK as being significantly more effective due to its novel Nanobody structure, which they claimed would afford patients superior clinical responses compared to traditional monoclonal antibodies like BIMZELX. The firm asserted that SLK could become a 'gold standard' treatment, facilitating profound improvements in patient outcomes.

However, upon assessment of the trial results, it became apparent that only one of the two conducted Phase 3 trials achieved statistical significance, showcasing efficacy levels that fell markedly short of those demonstrated by BIMZELX. Analysts quickly labeled these findings a