Aclaris Therapeutics (ACRS) Study Result summary

Study design and objectives

• Phase 1A trial evaluated ATI-052, a bispecific antibody targeting TSLP and IL-4Rα, in healthy adults using single (30, 120, 360, 720mg) and multiple ascending doses (240, 480mg) to assess safety, tolerability, PK, and PD.

• Primary goals included confirming safety/tolerability, establishing PK profile for monthly dosing, assessing PD response, and validating dual inhibition of TSLP and IL-4R.

• Baseline demographics were typical for healthy volunteer studies.

Safety and tolerability results

• ATI-052 was well tolerated across all cohorts, with no serious adverse events, discontinuations, or grade 3 drug-related adverse events.

• Most adverse events were mild, primarily injection site redness, and self-resolving.

• Drug-related adverse events were infrequent and mostly grade 1.

• No cases of conjunctivitis were observed.

Pharmacokinetics and dosing potential

• PK analysis showed dose-proportional increases in Cmax and AUC, with an effective half-life of at least 26 days, supporting potential for up to three-month maintenance dosing.

• Data support the possibility of dosing as infrequently as every three months.