Aclaris Therapeutics shares fell almost 90% after the biopharmaceutical company announced it is no longer continuing with the development of its rheumatoid arthritis therapeutic zunsemetinib.
The company said that its Phase 2b study of zunsemetinib did not meet its primary or secondary endpoints as there was no notable differentiation between zunsemetinib and placebo across any measures of efficacy after 12 weeks.
Based on these results, the company said it is also immediately halting enrollment in its ongoing Phase 2a trial of zunsemetinib in psoriatic arthritis.
“We are deeply disappointed with the results of this trial and for patients suffering from rheumatoid arthritis,” Aclaris CEO Doug Manion said in a statement.
“Despite this setback, we continue to look forward to the upcoming results of our Phase 2b trial of ATI-1777 in atopic dermatitis and initiating our Phase 2 clinical development program for ATI-2138.”
Results from the company’s 250-patient, six-arm, Phase 2b study of ATI-1777 in patients with mild, moderate or severe atopic dermatitis are expected by the end of 2023.
Aclaris shares traded down 86.6% at US$0.64 at noon on Monday.
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