Aclaris Therapeutics announces preliminary data from Phase 2 study of ATI-450

Aclaris Therapeutics announced preliminary topline results from a 12-week, Phase 2a, multicenter, randomized, placebo-controlled clinical study to investigate the efficacy, safety, tolerability, pharmacokinetics and pharmacodynamics of zunsemetinib, an investigational oral MK2 inhibitor, in patients with moderate to severe hidradenitis suppurativa. The study did not meet its primary endpoint of change from baseline in inflammatory nodule/abscess count of zunsemetinib 50mg BID versus placebo at week 12. The study also did not meet the secondary efficacy endpoints assessed in the topline data, including percentage of patients achieving HiSCR-50. The placebo effect observed across all efficacy endpoints was higher than what has been observed in other published HS studies reported to date. Zunsemetinib was generally well tolerated. Safety findings were generally consistent with observations from prior clinical studies of zunsemetinib. The most common treatment-emergent adverse events in patients treated with zunsemetinib were dizziness, diarrhea, headache, creatine phosphokinase elevation and acne, with a majority deemed mild to moderate in severity. No serious adverse events and no serious and/or opportunistic infections were observed with patients treated with zunsemetinib. Pharmacokinetics/Pharmacodynamics: PK and PD were generally consistent with observations from prior clinical studies of zunsemetinib. A preliminary analysis of endogenous plasma cytokines and chemokines in patients with a confirmed dose of study treatment on the day of blood draw, demonstrated zunsemetinib dependent inhibition relative to placebo.