Slide 1: SIGNAL-AA Part B 36-Week Topline Results
Exhibit 99.1 SIGNAL-AA Part B 36-Week Topline Results July 2026
Slide 2: Forward Looking Statements
Forward Looking Statements This presentation has been prepared by Q32 Bio Inc. (“we”, “us,” “our,” “Q32” or the “Company”) and is made for informational purposes only. The information set forth herein does not purport to be complete or contain all of the information you may desire. Statements contai
Slide 3: Today's Agenda: Management Joined by Alopecia Areata Key Opinion Leader
Q32 Bio Management Joined by Renowned Alopecia Areata Key Opinion Leader TODAY’S AGENDA Q32 Bio Leadership Introduction Bempikibart Overview Jodie Morrison Shelia Violette, Ph.D. Lee Kalowski, M.B.A. SIGNAL-AA Part B Results Chief Executive Officer Founder & President & Chief Scientific Officer Chie
Slide 4: SIGNAL-AA Part B Builds on Prior Proof of Concept Demonstrating Robust Clinical Activity at 36 Weeks
Bempikibart SIGNAL-AA: Part B Builds on Prior Proof Of Concept in Alopecia Areata Demonstrating Robust Clinical Activity at 36 Weeks Bempikibart continued to demonstrate a Robust clinical activity favorable safety profile; negligible ADA No Grade 3 or higher AEs and no new Week 36 Results safety sig
Slide 5: Bempikibart: Bifunctional Antibody for T-cell Mediated I&I Diseases
Bempikibart: Bifunctional Antibody for T-cell Mediated I&I Diseases With Demonstrated Activity in Alopecia Areata Bempikibart IL-7Rα antagonist antibody: Blocks IL-7 and TSLP signaling IL-7 receptor TSLP receptor • IL-7 regulates pathogenic T / T cells • TSLP is central regulator of dendritic eff me
Slide 6: Bempikibart Addresses the Root of the Problem: Inhibition of Pathogenic T-cells
Epidermis Dermis Bempikibart Addresses the Root of the Problem: Inhibition of Pathogenic T-cells that Directly Drive Hair Follicle Destruction and Suppress the Function of T-regs Hair Follicle Immune Dysregulation in Alopecia Areata Bempikibart is designed to address Local inflammation and destructi
Slide 7: Bempikibart SIGNAL Program in Severe/Very Severe Alopecia Areata
Bempikibart SIGNAL Program In Severe/Very Severe Alopecia Areata Designed To Enable Registrational Studies As Next Step Part A SIGNAL-AA Clinical Program Part A Part B 24-Week Primary Endpoint Completed 4Q24; 36-Week Primary Endpoint Complete 3Q26; Part A OLE Completed 2Q26 Off-Drug Follow-Up and OL
Slide 8: SIGNAL-AA Phase 2a Part B: Builds Upon Part A
SIGNAL-AA Phase 2a Part B: Builds Upon Part A Includes Loading Regimen and Dosing Through 36 Weeks Key Changes Treatment Period Off-Drug Period from Part A Bempikibart 200mg Efficacy and (n= 33) Safety Follow-up Loading dose regimen 1 Placebo (n=8 ) Follow Up 16 Weeks Loading Regimen: Continued Dosi
Slide 9: SIGNAL-AA Phase 2a Part B: Baseline Demographics
SIGNAL-AA Phase 2a Part B: Baseline Demographics mITT Population ITT Population mITT Population ITT Population Characteristics N = 25 N = 33 Characteristics N = 25 N = 33 Age, years Actual Baseline SALT Score Mean [SD] 41.92 [15.0] 40.7 [14.0] Mean [SD] 76.9 [17.2] 75.6 [17.8] Median 39.0 38.0 Med
Slide 10: PK Results in Part B: Steady State ~10 Weeks Earlier Than Part A
PK Results in Part B: Data Supports Steady State ~10 Weeks Earlier Than Part A Part A 100 Part B Mean Ctroughs Achieved ~3 fold higher in steady state the first month of concentrations 10 dosing compared ~10 weeks earlier 5 µg/mL to Part A 1 No change in the Negligible ADA known safety with no impac
Slide 11: Part B (mITT): Mean % Change from Baseline at Week 36
Part B (mITT): Mean % Change from Baseline at Week 36 10 35.3% mean reduction in SALT score (Severe Part B Severe and Very Severe Population (mITT, n=25) Part B Very Severe Population (mITT, n=6) 1 and Very Severe population ) Part B Severe Population (mITT, n=19) 0 Robust improvement in both Severe
Slide 12: Part B (mITT): Clinically Meaningful SALT-20 Achievement at Week 36
Part B (mITT): Clinically Meaningful SALT-20 Achievement at Week 36 SALT-20 Responders • Responses seen in severe and very severe patients • Baseline SALT scores in patients achieving SALT-20 10 range from 51 to 100 0 -10 -20 -30 -40 -50 -60 mITT ITT -70 (n=25) (n=33) -80 SALT-20 at Week 36: n (%) 1
Slide 13: Robust Part B Clinical Activity Supports Potential Paradigm Shift to Biologics
Robust Part B Clinical Activity in Alopecia Areata Supports Potential for Paradigm Shift to Biologics SIGNAL-AA Part B Efficacy Results at Week 36 (Responder Analysis) mITT population ITT population SALT-20 (% pts) 40.0% (10/25) 30.3% (10/33) SALT (% pts) 44.0% (11/25) 33.3% (11/33) 30 SALT (% pts)
Slide 14: Patient with Severe AA with Robust Response and Durability Off-Drug: SALT-10
Patient with Severe AA with Robust Response and Durability Off-Drug: SALT-10 at Week 24 and 36, SALT-0 at Week 44; Maintained Off-Drug Treatment Period 16 Weeks Off-Drug • 48-year-old female; Duration of current episode: 1.2 years Baseline Week 36 Week 52 SALT Score Through Study Treatment 100 90 80
Slide 15: Patient with Severe AA with Robust Response and Durability Off-Drug: SALT-20
Patient with Severe AA with Robust Response and Durability Off-Drug: SALT-20 at Week 24, SALT-10 by Completion Date; Maintained Off-Drug Treatment Period 12 Weeks Off-Drug • 33-year-old female; Duration of current episode: 1.4 years Baseline Week 32 Week 42 • Prior Oral JAKi experience SALT Score Th
Slide 16: Patient with Severe AA with Robust Response and Deepening Response Off-Drug
Patient with Severe AA with Robust Response and Deepening Response Off-Drug: SALT-20 at Week 36, SALT-10 at Week 48 and 52 Treatment Period 16 Weeks Off-Drug • 41-year-old female; Duration of current episode: 2.5 years Baseline Week 36 Week 52 SALT Score Through Study Treatment 100 90 80 70 60 50 40
Slide 17: Patient with Very Severe AA with Robust Response and Durability Off-Drug
Patient with Very Severe AA with Robust Response and Durability Off-Drug: SALT-20 at Week 36; Maintained Off-Drug Treatment Period 16 Weeks Off-Drug • 32-year-old male; Duration of current episode: 3.2 years Baseline Week 36 Week 52 SALT Score Through Study Treatment 100 90 80 70 60 50 40 30 20 10 0
Slide 18: Most Commonly Reported Treatment Emergent Adverse Events
Bempikibart SIGNAL-AA Part B: Most Commonly Reported Treatment Emergent Adverse Events; No Severe or Higher AEs Bempikibart N=33 N (% patients reporting at least one TEAE) 31 (93.9) Most Common TEAEs (>5%) • ISR incidence is Preferred Term Gr1 (Mild), n (%) Gr2 (Mod), n (%) Gr3 or Higher (Sev), n (%
Slide 19: Bempikibart May Redefine the Long-Term Management of Alopecia Areata
Bempikibart May Redefine the Long-Term Management of Alopecia Areata With Emerging Well-Tolerated, Selective and Efficacious Biologic Profile Development of biologics in Alopecia Areata have lagged the JAK inhibitors: Unique dynamic not seen elsewhere in the broader I&I landscape Set the Bar for Bio
Slide 20: Alopecia Areata Has Life-Altering Impact and Significant Unmet Need
Alopecia Areata Has Life-Altering Impact and Significant Unmet Need With Limited Treatment Options, Including JAK Inhibitors Carrying Black Box Warnings Alopecia areata unmet need persists Key Findings From Survey of 50 U.S. Dermatology Healthcare Providers “There's a large unmet need. Many patients
Slide 21: The US Alopecia Areata Market is Growing Despite Remaining Unmet Need
The US Alopecia Areata Market is Growing Despite Remaining Unmet Need By 2037, Estimated to be >$5B US Opportunity Future US Alopecia Areata Market Size (2037F) US Alopecia Areata Prevalence: Estimated Historical and 2026 Projected ~800k patients US Alopecia Areata Net Sales 1 (JAKi alopecia areata
Slide 22: SIGNAL-AA Program Supports Registration-Directed Program: Next Steps
Bempikibart SIGNAL-AA Program In Severe/Very Severe Alopecia Areata Supports Registration-Directed Program Bempikibart for Alopecia Areata Next Steps • Alopecia areata is a large and underserved • Results from ongoing Part B and totality of data from patient population with significant unmet need SI
Slide 23: Q&A with Renowned Alopecia Areata Key Opinion Leader
Q&A with Renowned Alopecia Areata Key Opinion Leader Q32 Bio Leadership Jodie Morrison Shelia Violette, Ph.D. Lee Kalowski, M.B.A. Chief Executive Officer Founder & President & Chief Scientific Officer Chief Financial Officer Key Opinion Leader Arash Mostaghimi, MD, MPA, MPH Associate Professor of D
Slide 24: SIGNAL-AA Part B 36-Week Topline Results
SIGNAL-AA Part B 36-Week Topline Results July 2026