Shares of the Malvern, Pa., company closed at $18.83 after trading as high as $19.95. They'd closed at $5.88 on Friday. And their 52-week low is 70 cents, set in the middle of last March.
Aclaris reported positive preliminary top-line results from a Phase 2a clinical trial of ATI-450, an investigational oral MK2 inhibitor, in subjects with moderate to severe rheumatoid arthritis.
In the trial, 19 subjects received either 50mg of ATI-450 twice daily or placebo in combination with methotrexate for 12 weeks, the company said.
“In this trial, ATI-450 demonstrated durable clinical activity, as defined by a marked and sustained reduction in DAS28-CRP and evaluation of ACR20/50/70 responses over 12 weeks. The mean change from baseline in DAS28-CRP score at week 12 was a 2.0 reduction in the treatment arm compared to a 0.35 increase in the placebo arm.”
Further, “the proportion of subjects with a DAS28-CRP score at week 12 of ≤ 3.2 (low disease activity or remission) was 40% and 0% in the treatment and placebo arms, respectively, and the proportion of subjects with a DAS28-CRP score of < 2.6 (remission) was 20% and 0% in the treatment and placebo arms, respectively,” the company said.
The druge was generally well tolerated. "No serious adverse events were reported and all adverse events were mild to moderate,” Aclaris said.
Aclaris said it expected to submit a full analysis of the Phase 2a data for publication in a peer-reviewed scientific journal.