Aclaris Therapeutics, Inc. · NASDAQ:ACRS
Aclaris Therapeutics — Corporate Update (April 2026)
30 slides from Aclaris Therapeutics's corporate update, Apr 28, 2026
Slide 1: Clinical Pipeline Update: ATI-052 Full SAD MAD Results; ATI-2138 for Lichen Planus
Clinical Pipeline Update: ATI-052: Full SAD MAD Results ATI-2138: Potential Mechanistically Complete Therapy for Lichen Planus April 28, 2026
Slide 2: Disclaimer and Cautionary Note Regarding Forward-Looking Statements
Disclaimer and Cautionary Note Regarding Forward-Looking Statements Any statements contained in this press release that do not describe historical facts may constitute forward-looking statements as that term is defined in the Private Securities Litigation Reform Act of 1995. These statements may be
Slide 3: Addressing Significant Markets: Th2 Driven Indications
Addressing Significant Markets Th2 Driven Indications 45 Total Addressable Market (TAM) 40 35 Global, 2028-2034 ($ billion) 30 25 20 15 10 5 0 Purigo Chronis Eosinophilic COPD Asthma Atopic nodularis spontaneous esophagitis dermatitis urticaria Significant opportunity for new innovative biologics ta
Slide 4: Opportunity to Redefine the Standard in Th2 Disease
Opportunity to Redefine the Standard in Th2 Disease • ATI-052: Harnesses the power of TSLP and IL-4Rα inhibition to create a potential best-in-class bispecific • Tezepelumab and Dupilumab drive multibillion dollar annual revenues across numerous indications • Combining mechanisms has the potential t
Slide 5: ATI-052: Potential Best-in-Class Bispecific mAb
ATI-052: Potential Best-in-Class Bispecific mAb Effective Dual Binding of TSLP and IL-4Rα Anti-IL4Rα scFV Designed to inhibit immune cells Anti-TSLP Fab downstream of the Th2 cascade Same anti-TSLP antibody binding regions of Bosakitug, designed to inhibit TSLP upstream of the Th2 cascade YTE Mutati
Slide 6: ATI-052: Longest Residence Time on TSLP
ATI-052: Longest Residence Time on TSLP Lower Dissociation Rate Drives Longer Residence Time Residence Time Dissociation of TSLP from mAbs (TR-FRET) (hours) TSLP TSLPR1 (n=3) (n=2) 416 402 1.0 Fractional Response (yi/yo) ATI-052 ATI-045 bosakitug ATI-052 GSK-5784283 V1 (hu3-13)* 14.3 8.11 22.1 3.59
Slide 7: Bosakitug Extensively Binds TSLP Binding Interface
Bosakitug Extensively Binds TSLP Binding Interface ATI-052 Has the Same Anti-TSLP Antibody Binding Regions of Bosakitug Tezepelumab Bosakitug (ATI-045) Bosakitug: Extensive Binding Interface Drives Higher Retention Time and Neutralization Duration of TSLP Only Bosakitug binds all six Light Chain and
Slide 8: Concurrent Binding of TSLP and sIL-4Rα to ATI-052
Concurrent Binding of TSLP and sIL-4Rα to ATI-052 Simultaneous Binding of TSLP and IL-4Rα TSLP:ATI-052 sIL-4Ra:ATI-052 ATI-052 Binding Sequence Stoichiometry* Stoichiometry* Demonstrates ATI-052 capture / sIL-4Ra dose-response n/a 2.25 High Affinity to ATI-052 capture / TSLP load / sIL-4Ra dose-resp
Slide 9: Concurrent Binding of TSLP and sIL-4Rα to ATI-052
Concurrent Binding of TSLP and sIL-4Rα to ATI-052 High Affinity to Both TSLP and IL-4Rα Comparison of Affinity for sIL-4Rα Binding to ATI-052 or ATI-052:TSLP Complex Parameter ATI-052 ATI-052:TSLP ATI-052 Binds KD (pM) 348 215 Both Targets Effectively High affinity a to either target is not altered
Slide 10: Comparison of ATI-052 vs Dupilumab + Tezepelumab
Comparison of ATI-052 vs Dupilumab + Tezepelumab ATI-052 Demonstrates Greater Potency than the mAb Combination mAb Concentration Antibody IC50 (nM) ATI-052 0.016 Dupilumab + 0.069 Tezepelumab Fold change 4.3 ATI-052 is Substantially More Potent than the Combination of Dupilumab and Tezepelumab 10
Slide 11: ATI-052 Placebo Controlled Phase 1a Program
ATI-052 Placebo Controlled Phase 1a Program Part A Single Ascending Dose (SAD) in Healthy Volunteers (HV) Treatment and Follow-up Period Cohort 1 (30mg): SC, N=8 D1-113 Cohort 2 (120mg): SC, N=8 D1-113 Randomization Screening 3:1 Cohort 3 (360mg): SC, N=8 D1-113 Cohort 4 (720mg): SC, N=8 D1-113 Part
Slide 12: Potential Best-in-Class Pharmacokinetic Profile
Potential Best-in-Class Pharmacokinetic Profile Supports Potential for Up to Every 3-Month Dosing SAD Cohort 1 (30 mg) SAD Cohort 2 (120 mg) MAD Cohort 1 (240 mg) SAD Cohort 3 (360 mg) MAD Cohort 2 (480 mg) SAD Cohort 4 (720mg) Dose proportional PK observed across pharmacologic dose range PK results
Slide 13: Ex-Vivo Stimulated PD Assay
Ex-Vivo Stimulated PD Assay High Hurdle for Complete Inhibition hWB Assays Robust PD activity ex vivo hWB closely 0.5 ng/mL TSLP stimulation—48 hours 2 ng/mL IL-4 stimulation—48 hours reflects the real biological environment in 140 CCL17 release (% pos ctrl - unstim) 100 patients with disease by mai
Slide 14: Potential Best-in-Class Pharmacodynamic Effect of ATI-052
Potential Best-in-Class Pharmacodynamic Effect of ATI-052 CCL17 Production (% Predose, Mean ±SEM) Note: No samples taken at weeks 8, 10, 14 and 18 TSLP Stimulated CCL17 (TARC): ATI-052 binds both targets Sustained, complete / effectively near complete inhibition observed for with complete inhibition
Slide 15: Exceptional Pharmacodynamic Response
Exceptional Pharmacodynamic Response Robust Target Engagement + Sustained Complete Inhibition in MAD Cohorts ATI-052 exhibited a potential best-in-class PD profile: • Dose and concentration dependent inhibition of IL-4 and TSLP-stimulated CCL17 (TARC) release observed across all SAD and MAD cohorts
Slide 16: Favorable Tolerability and Safety Profile of ATI-052
Favorable Tolerability and Safety Profile of ATI-052 Update Provides Confidence in Continued Development Full results confirm • Low rate of drug related treatment emergent adverse strong safety profile observed at interim events; predominantly Grade 1 analysis • No SAEs; no adverse events led to stu
Slide 17: Phase 1b POC Trial in Atopic Dermatitis
Phase 1b POC Trial in Atopic Dermatitis Enrollment and Dosing Ongoing Day 57 Top Line Readout 12 AD Patients EASI >21 ATI-052 Q1wk (five doses, 480 mg) Randomization Screening/ Washout 3:1 Active 12-week follow-up to Placebo Placebo Q1wk (five doses) Patient Screening Central photography to confirm
Slide 18: Phase 1b POC Trial in Asthma
Phase 1b POC Trial in Asthma Enrollment and Dosing Ongoing Day 29 Top Line Readout 16 Patients GINA steps 2-4 prior ATI-052 (single dose, 480 mg) Randomization Screening/ Washout 3:1 Active Six-week follow-up to Placebo Placebo (single dose) Adult asthmatics on GINA steps Type 2 asthma with active i
Slide 19: ATI-052: Next Steps
ATI-052: Next Steps Positive SAD/MAD Results Validate ATI-052; Clinical Program Rapidly Advancing Phase 1 Complete HV: SAD/MAD Ongoing / Next Steps Phase 1b POC Phase 1b POC • Phase 1b Asthma and AD POC Dosing Dosing ongoing Atopic dermatitis Asthma ongoing trials ongoing; dosing underway • Phase 1b
Slide 20: Clinical Pipeline Update: ATI-2138
Clinical Pipeline Update: ATI-2138: Potential Mechanistically Complete Therapy for Lichen Planus
Slide 21: ATI-2138: The Lichen Planus Opportunity
ATI-2138: The Lichen Planus Opportunity Mechanistically well matched JAK3 and cyclosporin provide POC Important unmet medical need: Significant market size White space opportunity and revenue potential Lichen planus Regulatory pathways may Potential for cost-effective allow for expedited review clin
Slide 22: Lichen Planus
Lichen Planus An Unaddressed Chronic, Inflammatory, Immune-Mediated Disorder Multiple impactful clinical subtypes Most common are erosive mucosal (oral), cutaneous, and lichen planopilaris Typical symptoms are debilitating Include pain, sores, severe itch, scales/plaques, hair loss, fatigue Lichen A
Slide 23: Lichen Planus is a Large and Unsatisfied Market
Lichen Planus is a Large and Unsatisfied Market Significant “White Space” US Opportunity • Prevalence of between 0.1% and 1.0% of the population – Up to 40% of patients seek treatment despite no FDA-approved targeted therapeutic interventions – ~25% of patients have moderate-to-severe disease • Ster
Slide 24: ATI-2138: Unique Bispecific-Like Mechanism
ATI-2138: Unique “Bispecific-Like” Mechanism First & Only Known Drug Inhibiting TCR Activation Upstream + Effector Cytokines Downstream ITK Inhibition Inhibition of Cytokine Signaling (Cytokine-Driven; Signal 3) Inhibition of T Cell Receptor (TCR) • Potent inhibition of JAK3 Signaling (Antigen-Drive
Slide 25: ATI-2138: Well Positioned in Lichen Planus
ATI-2138: Well Positioned in Lichen Planus Dual Pharmacology Creates Ideal Mechanistic Fit Lichen planus ATI-2138 • CD8-driven interface dermatitis; • Modulates TCR signaling and CD8 cytotoxic involvement of TCR/T cells T cell suppression Signal 1 Antigen • Aberrant activation cytotoxic CD8 T cells
Slide 26: ATI-2138: Next Steps
ATI-2138: Next Steps Mechanistically Fit for Lichen Planus and Other I&I Disorders Severe Hair Loss Phase 2a Complete (murine) Complete Atopic Dermatitis Alopecia universalis Ongoing / Next Steps Phase 2b • Lichen planus selected as program Lichen planus Initiation Phase 2b indication Mucosal 2H 202
Slide 27: ATI-052 SAD/MAD Results Exceeded Expectations
ATI-052 SAD/MAD Results Exceeded Expectations Pharmacokinetic Profile • Dose proportional PK observed across pharmacologic dose range Supports Potential for Extended Dosing • Linear half-life exceeds prior estimate of 26 days • Robust target engagement + complete/near complete target occupancy Stron
Slide 28: ATI-2138 May be Ideal Therapy for Lichen Planus
ATI-2138 May be Ideal Therapy for Lichen Planus • First and only known drug inhibiting TCR activation upstream + effector Mechanistically Well cytokines downstream Matched • Observed in AD to impact itch • Strong downregulation of fibrosis and Th1/2/17 activation markers Important Unmet Medical • De
Slide 29: Continued Clinical Momentum in 2026 & 2027
Continued Clinical Momentum in 2026 & 2027 Three Clinical Programs Ongoing; IND Expected in 2026 ATI-052 AD and Asthma POCs Bosakitug (ATI-045) ongoing Enrollment in Phase 2 in AD Top line POC results in AD complete Advancing Innovation and Asthma in 2H 2026 Top line results in 4Q 2026 potentially D
Slide 30: Clinical Pipeline Update: ATI-052 Full SAD MAD Results; ATI-2138
Clinical Pipeline Update: ATI-052: Full SAD MAD Results ATI-2138: Potential Mechanistically- Complete Therapy for Lichen Planus April 28, 2026