Q32 Bio (QTTB) Stifel 2024 Immunology and Inflammation Virtual Summit summary

Company overview and pipeline

• Focuses on complement pathway therapeutics, with origins tied to regulatory complement genes on chromosome 1q32.

• Advanced a clinical-stage asset into phase II for renal diseases (IgAN, C3G, lupus nephritis) and ANCA-associated vasculitis.

• Expanded pipeline with acquisition of bempi, a bifunctional antibody targeting IL-7 and TSLP, enabling broad application in Th1/Th2 diseases.

• Four phase II trials are ongoing, funded through mid-2026, with key readouts expected in Q4 2024.

Bempi mechanism and differentiation

• Bempi blocks both IL-7 and TSLP signaling via high-affinity binding to IL-7 receptor alpha, impacting a wide range of immune cells.

• TSLP modulates Th2 differentiation and affects multiple cell types, while IL-7 amplifies Th2 responses and IL-4 production.

• The antibody is fully human, with high binding affinity and engineered to eliminate effector function and complement activation.

• Subcutaneous dosing achieves full receptor blockade at low mg/kg, with favorable PK/PD and safety profiles in phase I.

Clinical trial design and strategy

• Atopic dermatitis (AD) and alopecia areata (AA) are lead indications, targeting both Th1 and Th2 pathways in AD and primarily Th1 in AA.

• Phase II AD trial uses a monotherapy design, with endpoints and population aligned to contemporary studies; primary endpoint is EASI score change at week 14.

• Dose selection based on robust PK/PD data, with 200 mg flat dose showing consistent safety and efficacy in both healthy and AD patients.

• Bar for phase III advancement in AD is a 30% placebo-adjusted mean change in EASI, with emphasis on novel MOA and broader T cell inhibition.

• AA trial mirrors ritlecitinib phase IIa design, focusing on severe patients (SALT 50-100) and 24-week endpoint; a 20%+ placebo-adjusted SALT change is considered meaningful.