Climb Bio (CLYM) investor relations material

Key program updates and clinical strategy

• Lead CD19 monoclonal antibody, Budoprutug, is in phase II for PMN and phase I-B for ITP and SLE, with recent data showing subcutaneous formulation potential and more readouts expected this year and next.

• Second asset is an APRIL-only monoclonal antibody with sweeper mechanism, targeting IgA nephropathy, leveraging pH-dependent binding and LALA mutation for extended half-life.

• Ongoing studies in Australia and China with partner Mabworks provide parallel SAD/MAD data, aiming to accelerate development and optimize dose-ranging.

• Upcoming data disclosures planned at ERA (translational modeling, phase I design, initial safety) and potentially ASN later in the year.

• Collaboration with Mabworks is seen as a differentiator for global development and data generation.

Industry landscape and competitive positioning

• Anti-APRIL therapies are advancing, with next-generation agents aiming for less frequent dosing (every 8–12 weeks) and improved safety/efficacy over first-generation monthly dosed assets.

• There is significant room for improvement in proteinuria reduction and patient targeting, with higher doses showing better outcomes in phase II studies.

• Updated KDIGO guidelines now target lower proteinuria thresholds (0.3g), supporting the need for more effective therapies.

• Combination therapies (e.g., complement and APRIL) are anticipated as a future trend, but current focus remains on distinct, optimized single-agent approaches.

• Regulatory perspectives are evolving, with FDA and NKF recognizing proteinuria lowering as a surrogate for eGFR stabilization.

Scientific insights and product differentiation

• Sweeper technology and LALA mutation are expected to enhance pharmacodynamics and clinical profile, potentially enabling quarterly maintenance dosing.

• Non-human primate data suggest rapid onset and depth of IgA reduction, with APRIL inhibition showing promise for chronic therapy in young patient populations.

• CD19 antibody approach offers community-based dosing, subQ formulation, and potential for treatment-free intervals, differentiating from CAR-T and TCE modalities.

• Budo’s high sensitivity B-cell assay and picomolar affinity to CD19, along with enhanced ADCC, are key differentiators from competitors like UPLIZNA.

• Targeting CD19 depletes plasmablasts while preserving long-lived plasma cells, reducing need for revaccination and supporting the “Goldilocks” approach for autoimmune indications.