Arctic Therapeutics (ATx), an Iceland-based clinical-stage biopharmaceutical company, announced on Wednesday that the first patients have been enrolled in a Phase IIa randomised, double-blind, placebo-controlled clinical trial evaluating the safety and efficacy of topical AT-004 in patients with acne vulgaris (AV).

The study was approved by the European Medicines Agency (EMA) in December 2025 and is being conducted across three clinical sites in Denmark.

According to ATx, AT-004 is an acetylcholinesterase inhibitor that represents a novel and innovative approach to treating inflammatory skin diseases. By targeting the non-neuronal cholinergic anti-inflammatory pathway, a biological system present in human skin involved in regulating inflammation and pro-inflammatory cytokines such as TNF-alpha, AT-004 has the potential to introduce a first-in-class mechanism in dermatologic therapy. Additionally, preclinical and early clinical findings suggest that AT-004 could deliver robust local anti-inflammatory effects without systemic exposure, positioning it as a promising investigational treatment option beyond AV.

The Phase IIa study designed to evaluate the safety, tolerability, and preliminary efficacy of AT-004 in adults with AV. It will include 60 participants aged 18 to 45, randomised 1:1 to receive either AT-004 or placebo for a 12-week treatment period, with 30 participants in each arm.