Aclaris Therapeutics, a Wayne, Pennsylvania-based clinical-stage biopharmaceutical company developing treatments for immuno-inflammatory diseases, has priced a public offering expected to raise about $50 million, the company announced on October 27, 2026. The same morning, Aclaris reported results from two Phase 1b proof-of-concept trials of ATI-052, its investigational bispecific antibody, in atopic dermatitis (AD) and asthma.
“Consistent with our development strategy, we intend to prioritize initiating a Phase 2b trial in EoE early next year and provide an update on plans for a potential additional indication in the near term,” said Dr. Neal Walker, Chief Executive Officer of Aclaris.
Inside the Offering
Aclaris is selling 7,785,714 shares of common stock at $3.50 per share. Some investors will instead receive pre-funded warrants to buy 6,500,000 shares at $3.49999 each. A pre-funded warrant is paid for almost entirely upfront and can be converted into a share for a nominal exercise price, here $0.00001.
Investors in the offering include TCGX, RA Capital Management, Invus, and a large mutual fund. Gross proceeds are expected to total about $50 million, before underwriting discounts, commissions, and other expenses. The offering was expected to close on October 28, 2026, subject to customary closing conditions. Leerink Partners, Piper Sandler, Cantor, and LifeSci Capital are serving as joint bookrunning managers.
Early Results for ATI-052
ATI-052 is designed to block two targets at once. It inhibits thymic stromal lymphopoietin (TSLP), a protein that sits at the top of the inflammatory cascade. It also blocks the interleukin-4 receptor alpha (IL-4Rα), which shuts down signaling from IL-4 and IL-13, two key drivers of allergic inflammation.
The two small, randomized, double-blind, placebo-controlled trials were primarily designed to assess safety. ATI-052 was well tolerated across both, according to Aclaris. Side effects were mostly mild (Grade 1), with no severe (Grade 3 or 4) events and no discontinuations because of side effects. No cases of conjunctivitis were observed.
Atopic dermatitis: The trial enrolled 14 patients with severe AD, who received five weekly doses of ATI-052 or placebo. At day 57, patients on ATI-052 saw a 58% average improvement in the Eczema Area and Severity Index (EASI), a measure of skin severity, compared with 13% on placebo. They also reported a 38% average improvement in itch, while itch worsened 5% in the placebo group.
Asthma: The trial enrolled 16 patients with mild-to-moderate asthma, who received a single dose of ATI-052 or placebo. By day 15, patients on ATI-052 saw a 59% average reduction in fractional exhaled nitric oxide (FeNO), a marker of airway inflammation, compared with 15% on placebo. Lung function, measured by forced expiratory volume in one second (FEV1), improved by 200 mL after placebo adjustment at day 15.
Next Up: Eosinophilic Esophagitis
Aclaris now plans to prioritize Phase 2b development of ATI-052 in eosinophilic esophagitis (EoE), a chronic allergic inflammatory disease of the esophagus. The company says a focused program in EoE fits its development strategy and capital management. It expects to start the trial early next year.
Aclaris holds exclusive worldwide rights to ATI-052, excluding Greater China.
About Aclaris Therapeutics
Aclaris develops small-molecule and biologic drugs for immuno-inflammatory diseases. Its KINect® platform designs kinase inhibitors, small molecules that block enzymes involved in chronic inflammation, autoimmune disease, and cancer growth. The company is also developing monoclonal and bispecific antibodies, including dual-targeting approaches. Aclaris also operates Confluence Discovery Technologies, a contract research organization that provides drug discovery and early development services to pharma and biotech companies.
