Aclaris Therapeutics, Inc. · NASDAQ:ACRS
Aclaris Therapeutics — Investor Presentation (January 2026)
65 slides from Aclaris Therapeutics's investor presentation, Jan 12, 2026
Slide 1: Corporate Overview January 2026
Corporate Overview January 2026 EMPOWERING PATIENTS THROUGH THERAPEUTIC INNOVATION
Slide 2: Forward-looking statements
2 Any statements contained in this presentation 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 identified by words such as “anticipate,” “believe,” “expect,” “int
Slide 3: Corporate Strategy: Commitment to Therapeutic Innovation
Aclaris Therapeutics Innovation Driven Patient Focused Four anticipated clinical programs Multiple anticipated inflection points in 2026 Validated targets; positioned in the oral and antibody space Bispecific and ITK oral programs have the potential to be paradigm changing in multiple indications Ad
Slide 4: Patient populations in dermatology, respiratory and GI diseases
4 Atopic dermatitis 26M 204M Alopecia areata 6.7M 160M Vitiligo 2-3M 70M Lichen planus 0.6M 12M Dermatology Respiratory GI IBD 2.4M 7M U.S. Patients Global Patients Sources: Eczema stats: National Eczema Association (accessed 07/31/25); National Alopecia Areata Foundation (Accessed 07/31/25); Vitili
Slide 5: Significant Future Value of Addressing I&I Diseases
5 Sources: Eczema stats: National Eczema Association (accessed 07/31/25); National Alopecia Areata Foundation (Accessed 07/31/25); Vitiligo Facts: Global Vitiligo Foundation (accessed 07/31/25); Precedence Research; Forbes Business Insights; American Medical Association; American Lung Association; G
Slide 6: Substantial Opportunities in I&I for Innovative Drugs
Substantial Opportunities in I&I for Innovative Drugs Potential to Address Significant Gaps in Unsatisfied I&I Indications 6 Opportunities for Orals • Faster onset, durable, consistent effect • Broader efficacy across heterogenous populations • JAK-like efficacy with no black box warning • Improved
Slide 7: Development strategy: TSLP, IL-4R, ITK, JAK3 targets
7 Master activator of innate & adaptive immune responses at epithelial surfaces Binds to cytokines IL-4 and IL-13, orchestrating allergic responses and immune regulation Critical for T lymphocyte differentiation, proliferation and activation Regulates growth, maturation and activation of many immune
Slide 8: Opportunity to Impact Major I&I Indications
Opportunity to Impact Major I&I Indications Assets in Development May Be Broadly Applicable to Significant Diseases 8 Atopic Dermatitis (AD) Psoriasis Vitiligo Alopecia areata Cicatricial (scarring) alopecia Lichen planus Prurigo nodularis Chronic spontaneous urticaria Asthma Rhinitis COPD Eosinophi
Slide 9: Broad I&I Development Pipeline
Broad I&I Development Pipeline 9 Preclinical Phase 1 Phase 2 Phase 3 Partner Bosakitug (ATI-045) TSLP mAb Subcutaneous Atopic Dermatitis (moderate-to-severe) Severe Asthma CTTQ (China)* Chronic Rhinosinusitis with Nasal Polyps CTTQ (China)* COPD CTTQ (China)* ATI-2138 ITK/JAK3 Inhibitor Oral Atopic
Slide 10: Bosakitug (ATI-045): Highly Differentiated Anti-TSLP Antibody
Bosakitug (ATI-045): Highly Differentiated Anti-TSLP Antibody Investigational Product Candidate with Best-in-Class Potential
Slide 11: Targeting Thymic Stromal Lymphopoietin (TSLP)
• Pleiotropic and broad activity – Master regulator of type 2 (Th2) immune responses at the barrier surfaces of skin and the respiratory/ gastrointestinal tract – Drives eosinophilic and neutrophilic inflammation and acts on a wide variety of adaptive, innate, and structural cells – Broad activity:
Slide 12: Targeting TSLP May Impact Nonhistaminergic Itch
12 Adapted from Auyeung K, Kim B et al., Annals of Allergy, Asthma, and Immunology. 2023. DOI: 10.1016/j.anai.2023.08.008 (e.g., TSLP, IL-4, IL-31) • Peripheral pruritus (itch) is mediated by histamine-dependent or histamine-independent mechanisms • Nonhistaminergic itch is a significant concern in
Slide 13: High Potency Therapeutics are Key to Effectiveness
High Potency Therapeutics are Key to Effectiveness Driving High Efficacy in Dermatological Disease • Abs must engage ligands at the site of action • Key variables related to efficacy – TSLP concentration at site of lesion – Antibody concentration at site of lesion • Concentration of mAb in general c
Slide 14: Bosakitug: High Affinity, Low Dissociation Rate
Bosakitug: High Affinity, Low Dissociation Rate • Very high affinity to TSLP • Extremely low dissociation rate from TSLP* leading to long residence time and enhanced neutralization activity • Very high potency • Unique binding characteristics to TSLP • ~23-day half-life that can potentially support
Slide 15: Bosakitug: Long Residence Time
Bosakitug (and ATI-052) demonstrates very slow dissociation kinetics from TSLP Residence time for Bosakitug (and ATI-052) is ~20-100x longer than comparator antibodies 15 1. SPR: Residence Time based on apparent dissociation constant (Kd) using standard TSLPR immobilization density and bivalent fit;
Slide 16: Bosakitug: Potential Best-in-Class Potency
Bosakitug is the most potent of the TSLP/TSLPR antibodies evaluated in blocking CCL17 production ATI-052 retains much of the potency for TSLP functional blockade 16 *Biosimilar; **Analog Bosakitug: Potential Best-in-Class Potency Greater Potency Than Other TSLP/TSLPR Antibodies NONCLINICAL VALIDATIO
Slide 17: Potency Advantage of Bosakitug vs Tezepelumab
Potency Advantage of Bosakitug vs Tezepelumab Relationship of Potency and Exposure to Extent of TSLP Inhibition • Bosakitug is expected to cover multiples over the concentration needed for 99% inhibition of TSLP at the site of action based on its in vitro potency • The highest dose of Tezepelumab ma
Slide 18: Phase 2a POC Monotherapy Trial Design
Clinical Translation: Positive Clinical Results Phase 2a (US-Based) POC Monotherapy Trial 18 Bosakitug 300 mg QW Bosakitug 300 mg Q2W Screening/ Washout up to 30 days 12 Week Follow-up Week 26 (2 weeks after last dose) Primary endpoint analysis Enrolled: 22 subjects (17 completed treatment) at 7 US-
Slide 19: Exposure and Efficacy Time Profile
Bosakitug Exposure and Efficacy Time Profile Demonstrated Sustained Clinical Response After the Last Dose 0 4 8 12 16 20 24 28 32 0.01 0.1 1 10 100 0 20 40 60 80 100 Time (Week) Concentration (μg/mL) Percent Change from Baseline of EASI Score (%) Last Dose Simulated Mean Conc. Observed Conc. Observe
Slide 20: Bosakitug Demonstrated Improvement in Efficacy Measures
Phase 2a (US-Based) POC Monotherapy Trial Bosakitug Demonstrated Improvement in Efficacy Measures 20 CLINICAL RESULTS
Slide 21: Phase 2 Monotherapy Trial Ongoing
Phase 2 Monotherapy Trial Ongoing Enrollment Proceeding to Plan 21 Placebo Week 0 & 2 Bosakitug Week 0 & 2 Placebo Q2W, Week 4 through Week 22 Bosakitug 300 mg Q2W, Week 4 through Week 22 Screening/ Washout up to 30 days 12 Week Follow-up Randomization 2:1 Active to Placebo Week 24 (2 weeks after la
Slide 22: Bosakitug: Next Steps
22 Bosakitug: Next Steps Competitively Positioned as Potential Best-in-Class TSLP mAb Phase 2 Atopic dermatitis Potential next targets Chronic Spontaneous Urticaria (CSU) EOE Ashma (partner) Phase 1 HV: SAD/MAD Ongoing Top line results in 2H2026 Complete Complete Phase 2a Atopic dermatitis Ongoing /
Slide 23: ATI-052: Anti-TSLP x IL-4Rα Bispecific Antibody Program
ATI-052: Anti-TSLP x IL-4Rα First Generation Bispecific Antibody Program Highly Potent and Bioactive Investigational Product Candidate
Slide 24: ATI-052: Potential Best-in-Class Bispecific mAb
ATI-052: Potential Best-in-Class Bispecific mAb Effective Dual Binding of TSLP and IL-4Rα ATI-052 CH2 CH3 CH2 CH3 24 Same anti-TSLP antibody binding regions of Bosakitug, designed to inhibit TSLP upstream of the Th2 cascade • Retains dissociation kinetics, residence time, and potency advantages of b
Slide 25: ATI-052: Longest Residence Time on TSLP
Dissociation of TSLP from mAbs (TR-FRET) 0 1000 2000 3000 4000 0.0 0.5 1.0 Time (min) Fractional Response (yi/yo) ATI-045 ATI-052 GSK-5784283 V1 (hu3-13)* GSK-5784283 V2 (hu179-33)* Solrikitug/MK-8226** Tezepelumab** Residence Time (hours) 416 402 14.3 8.11 22.1 3.59 20.7 ATI-052 ATI-045 Tezepelumab
Slide 26: 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 26 a ATI-052 Binds Both Targets Effectively High affinity to either target is not altered by the binding to the other Comparison of Affinity for sIL-4Rα Binding to ATI-052 or ATI-052:TSLP Complex Comparison of Af
Slide 27: Simultaneous Binding of TSLP and IL-4Rα
Concurrent Binding of TSLP and sIL4Rα to ATI-052 Simultaneous Binding of TSLP and IL-4Rα 27 a ATI-052 Demonstrated High Affinity to Both Targets Simultaneously: ATI-052 binds ~two molecules of TSLP and sIL-4Rα with the potential to saturate all 4 binding sites at the same time TSLP:ATI-052 sIL-4Ra:A
Slide 28: ATI-052 vs Dupilumab + Tezepelumab
Comparison of ATI-052 vs Dupilumab + Tezepelumab ATI-052 Demonstrates Greater Potency than the mAb Combination ATI-052 is Substantially More Potent than the Combination of Dupilumab and Tezepelumab mAb Concentration Antibody IC50 (nM) ATI-052 0.016 Dupilumab + Tezepelumab 0.069 Fold change 4.3 28 NO
Slide 29: Comparison of IL-4/IL-13 Monoclonal Antibodies
Comparison of IL-4/IL-13 Monoclonal Antibodies IL-4-induced CCL17 release IL-13-induced CCL17 release TSLP-induced CCL17 release IL-4+IL-13-induced CCL17 release Antibody concentration [nM] 0.00001 0.0001 0.001 0.01 0.1 1 10 100 CCL17 (% stim) 0 20 40 60 80 100 120 140 160 Antibody concentration [nM
Slide 30: Positive Interim Data: ATI-052 Phase 1a SAD and MAD Trial
Positive Interim Data: ATI-052 Healthy Volunteer Phase 1a SAD and MAD Trial Patient Focused Innovation Interim results as of December 31, 2025
Slide 31: Interim ATI-052 Results Exceeded Expectations
Interim ATI-052 Results Exceeded Expectations 31 Result ATI-052 was found to be well tolerated with a favorable safety profile across all SAD and MAD cohorts, with doses of up to 720 mg No conjunctivitis observed in any cohort Confirm Favorable Tolerability and Safety Profile Confirm Pharmacokinetic
Slide 32: ATI-052 Placebo Controlled Phase 1a Program
ATI-052 Placebo Controlled Phase 1a Program 32 Cohort 1 (30mg): SC, N=8 D1-113 Screening Randomization 3:1 Cohort 3 (360mg): SC, N=8 D1-113 Cohort 4 (720mg): SC, N=8 D1-113 Cohort 2 (120mg): SC, N=8 D1-113 Part A Single Ascending Dose (SAD) in Healthy Volunteers (HV): Dosing Complete Part B Multiple
Slide 33: Baseline Characteristics
Single ascending dose (SAD) Multiple ascending dose (MAD) ATI-052 Cohort 1 (30 mg) N=6 ATI-052 Cohort 2 (120 mg) N=6 ATI-052 Cohort 3 (360 mg) N=6 ATI-052 Cohort 4 (720 mg) N=6 Placebo N=8 ATI-052 Cohort 1 (240 mg) N=6 ATI-052 Cohort 2 (480 mg) N=6 Placebo N=4 Total N=48 Age (yrs), mean (SD) 40.0 (9
Slide 34: ATI-052 Well Tolerated with Favorable Safety Profile
Single ascending dose Multiple ascending dose Overall trial ATI-052 Cohort 1 (30 mg) N=6 ATI-052 Cohort 2 (120 mg) N=6 ATI-052 Cohort 3 (360 mg) N=6 ATI-052 Cohort 4 (720 mg) N=6 Placebo N=8 ATI-052 Cohort 1 (240 mg) N=6 ATI-052 Cohort 2 (480 mg) N=6 Placebo N=4 Total N=48 ≥1 TEAE (n, %) 4 (66.7) 1
Slide 35: Favorable Tolerability and Safety Profile of ATI-052
35 Favorable Tolerability and Safety Profile of ATI-052 Provides Confidence in Continued Development • No SAEs; no adverse events led to study discontinuation • Low rate of adverse events (AEs); Predominantly Grade 1 • The most common AE: Injection site redness; self-resolving and generally mild (Gr
Slide 36: Strong Pharmacokinetic Profile
36 Strong Pharmacokinetic Profile Dose proportional PK observed across pharmacologic dose range BLQ imputed as zero; mean concentrations below 0.1 not shown CLINICAL RESULTS
Slide 37: Strong PK Profile Supports Potential Extended Dosing
37 Strong PK Profile Support Potential Extended Dosing Dose Proportional PK Observed Across Pharmacologic Dose Range • Dose proportional PK was observed; dose proportional increases in Cmax and AUC observed • PK results provide an effective half-life of at least 26 days Potential best-in-class PK pr
Slide 38: Ex-Vivo Stimulated PD Assay in Human Whole Blood
Ex-Vivo Stimulated PD Assay Bridging to Human Whole Blood (HWB) • TSLP and IL-4R both modulated CCL17 release in PBMC • For the SAD/MAD study, this assay was adapted to human whole blood to assess the following: o TSLP stimulated CCL17 in whole blood o IL-4 stimulated CCL17 in whole blood Robust PD
Slide 39: Strong and Sustained Effect of ATI-052
Strong and Sustained Effect of ATI-052 ATI-052 binds both targets effectively with complete inhibition at pharmacologically relevant doses for an extended time beyond the PK profile Sustained, complete / near complete inhibition of ex-vivo stimulated responses observed for at least 3 weeks at 360 mg
Slide 40: Strong Pharmacodynamic Response
40 Strong Pharmacodynamic Response Robust Target Engagement + Near Complete Occupancy at Low Doses ATI-052 exhibited a potential best-in-class PD profile: • Dose and concentration dependent inhibition of IL-4 and TSLP-stimulated CCL17 release observed • Cohort 1 (30 mg), 2 (120 mg) and 3 (360 mg) da
Slide 41: Unique Binding Attributes and Clinical Potential
41 Unique Binding Attributes Clinical Potential Simultaneous Binding of TSLP and IL-4Rα High affinity to both targets simultaneously: ATI-052 binds two molecules of TSLP and sIL-4Rα Effective Binding of TSLP and IL-4Rα ATI-052 binds both targets effectively; high affinity of either targets is not al
Slide 42: ATI-052: Next Steps
42 ATI-052: Next Steps Positive Interim Results Validate ATI-052; Clinical Program Rapidly Advancing Ongoing / Next Steps • Phase 1b AD POC trial ongoing • Initiate Phase 1b asthma POC trial: 1Q 2026 • Phase 1b top line POC results: 2H 2026 • Initiate Phase 2b AD trial: 2H 2026 • Complete assessment
Slide 43: Next-Generation Multispecific Antibodies
Next-Generation Multispecific Antibodies
Slide 44: Next Generation Bispecific Antibodies Progressing Toward IND
Next Generation Bispecific Antibodies Progressing Toward IND Multispecific Ab development Progressing Toward IND Multispecific approach enables synergistic target binding and addresses shortcomings of multi-drug administration Additional bispecific and trispecific modalities under initial considerat
Slide 45: Opportunities for Aclaris Next Generation BsAbs
45 0 Pruritis (Itch) Alarmin Combinations Eosinophil-Driven Diseases • TSLP combinations with itch mediators may have a positive impact on itch and QoL in AD and other dermatological diseases • Could impact initiation of allergic response and associated downstream inflammation and enhance anti-viral
Slide 46: ATI-2138: Novel ITK/JAK3 Inhibitor for T Cell-Mediated Diseases
ATI-2138: A First Generation Novel ITK/JAK3 Inhibitor for T Cell-Mediated Diseases Potent and Selective Investigational Product Candidate with Strong Tolerability Profile
Slide 47: Critical T Cell Receptor Pathway: ITK
Critical T Cell Receptor (TCR) Pathway Interleukin-2-Inducible T-cell Kinase (ITK): Key Kinase Involved in TCR Signaling Antigen-presenting cell T-cell Lck LAT Phosphorylation Zap-70 CD3 CD4 MHC Antigen SLP-76 ITK TCR δ ε ε γ α β Ca2+ ER Ca2+ Ca2+ Ca2+ Ca2+ Ca2+ Ca2+ Ca2+ Nucleus Cytoplasm Cytoplasm
Slide 48: ITK Inhibition: Broadly Applicable in I&I Pathways
48 ITK Inhibition: Broadly Applicable in I&I Pathways Comparative Impact of ITK Inhibition TARGET VALIDATION
Slide 49: Potent Inhibition of ITK and JAK3 with ATI-2138
TCR APC T Cell Proliferation Differentiation Activation γc cytokines JAK3 pSTAT5 ATI-2138 T Cell NK Cell Potent Inhibition of ITK and JAK3 with ATI-2138 Selective Oral Small Molecule Covalent ITK & JAK3 Inhibitor for I&I Disease • Investigational oral compound which interrupts T cell receptor (TCR)
Slide 50: Unique Dual Pharmacology of ATI-2138
Unique Dual Pharmacology of ATI-2138 50 Regulation of T cell development and function both upstream (ITK) and downstream (JAK3) High potency for inhibiting both ITK and JAK3 Inhibiting both pathways may provide a more potent and complete anti-inflammatory response As both targets are restricted in e
Slide 51: ATI-2138: Anti-Inflammatory Activity
ATI-2138: Anti-Inflammatory Activity Strong Anti-Inflammatory Activity Shown in Various Murine Models IBD Mouse T Cell Transfer Vitiligo Score 3 0 6 9 12 15 18 51 ATI-2138 has demonstrated robust anti-inflammatory activity in mouse models of disease: Inflammatory Bowel Disease, Vitiligo, and Rheumat
Slide 52: ATI-2138: Best-in-Class Potential
ATI-2138: Best-in-Class Potential Unique Dual Pharmacology Creates Best-in-Class Potential ITK: HWB αCD3 Stimulated IFNγ Release JAK3: HWB IL2 Stimulated IFNγ Release 0.1 1 10 100 1000 10000 0 20 40 60 80 100 120 140 nM IFNg Production (% Stim) ATI-2138 Ritlecitinib 0.1 1 10 100 1000 10000 0 20 40 6
Slide 53: ATI-2138 Compared to CPI-818 (Soquelitinib)
ATI-2138: Validating the Potency Advantage ATI-2138 Compared to CPI-818 (Soquelitinib) • ATI-2138 is 15-38x more potent than CPI-818 in inhibiting the ITK enzyme activity • ATI-2138 is significantly more potent than CPI-818 in blocking the Th2 derived cytokines, IL-4, IL-5 and IL-13 (30-100x) ITK, I
Slide 54: Phase 2a Trial in Atopic Dermatitis: Complete
Phase 2a Trial in Atopic Dermatitis (AD): Complete 54 ATI-2138 (10mg BID) Screening/ Washout up to 30 days Two Weeks Follow-up Week 12 Enrolled: 14 subjects Primary endpoint analysis Moderate-to-Severe AD Treatment Period: 12 Weeks CLINICAL RESULTS Results: • Favorable safety profile • Efficacy acro
Slide 55: Phase 2a Trial in Atopic Dermatitis: Efficacy Results
PP-NRS: % of Pts with ≥4 Point Improvement in Worst Itch over Prior 24 Hours Phase 2a Trial in Atopic Dermatitis: Efficacy Results At week 12: 60.5% mean (median = 76.8%) improvement in EASI score in patients (n=10) receiving 10mg BID of ATI-2138 Rapid response: After four weeks of treatment* • BSA
Slide 56: ATI-2138 Mechanistically Unique; PD Supported Efficacy
ATI-2138 is Mechanistically Unique; PD Supported Observed Clinical Efficacy 56 Understanding PK/PD • ITK Assay – αCD3/aCD28 ex vivo stim mRNA (IL-2 and IFNγ) production • ITK Target Occupancy • JAK3 Assay – IL-15 ex vivo stim IFNg protein production • Immunophenotyping Relating PD to Efficacy • Punc
Slide 57: Phase 2a Trial in AD: PD Assessments
Phase 2a Trial in Atopic Dermatitis: PD Assessments ITK Pathway Mediated Anti-Inflammatory Activity in Skin and Plasma • Marked and sustained target occupancy and functional ITK inhibition across dosing interval • ATI-2138 significantly downregulated multiple immune pathways in skin and plasma, with
Slide 58: ATI-2138: Next Steps
58 Potential targets Alopecia areata Lichen planus Prurigo nodularis Vitiligo others Phase 1 HV: SAD/MAD ATI-2138: Next Steps Oral Small Molecule Covalent ITK & JAK3 Inhibitor for I&I Disease Potential applicability in a variety of I&I indications based on dual pharmacology / MOA Planned Initiation:
Slide 59: Next Generation JAK-Sparing ITK Inhibitors
Next Generation JAK-Sparing ITK Inhibitors Novel Selective Inhibitors Designed to Limit JAK Inhibitory Activity
Slide 60: Next Generation JAK-Sparing ITK Inhibitor Program
Next Generation JAK-Sparing ITK Inhibitor Program Progressing Toward IND Next Gen ITK Inhibitor Program Progressing Toward IND Developing highly potent JAK-sparing compounds; significantly more efficient at inactivating ITK than CPI-818 Opportunity for total ITK occupancy at low doses without impact
Slide 61: Potentially beneficial in Th1, Th2, and Th17-driven diseases
Potentially beneficial in Th1, Th2, and Th17-driven diseases 61 • Psoriasis • Celiac disease • IBD • Alopecia • SO Transplant Rejection • Eosinophilic esophagitis • Vitiligo • Prurigo nodularis • Asthma • COPD • Atopic Dermatitis • Rhinitis • CSU • Others IL-4R: Dupixent® (dupilumab) IL-13: Ebglyss®
Slide 62: Broad Clinical and Preclinical I&I Pipeline
z ITK Franchise Antibody Franchise Broad Clinical and Preclinical I&I Pipeline Developing Potential Best-in-Class Inhibitors of Immunoinflammatory Cascade 62 First Generation Next Generation Monoclonal Antibodies Multispecific Antibodies ATI-2138 ITK/JAK3 Phase 2a Complete ITK Inhibitors Preclinical
Slide 63: Continued Clinical Momentum in 2026 and 2027
Continued Clinical Momentum in 2026 and 2027 Four Expected Clinical Programs in 2026 Bosakitug (ATI-045) Phase 2 in AD ongoing Top line results in 2H 2026 ATI-052 AD POC ongoing; Asthma POC: 1Q 2026 Top line POC results in AD and Asthma in 2H 2026 Start AD Phase 2b: 2H 2026 ATI-2138 Start Phase 2 in
Slide 64: Company Summary: Commitment to Therapeutic Innovation
64 Proven track record of R&D, business development, and scientific leadership in immuno-inflammatory diseases Integrated approach to small and large molecule discovery enables targeted design of novel product candidates from concept through lead optimization Executing on multiple therapeutic progra
Slide 65: Corporate Overview January 2026
Corporate Overview January 2026 EMPOWERING PATIENTS THROUGH THERAPEUTIC INNOVATION
Aclaris Therapeutics — Investor Presentation (January 2026) on 6ix