Summary of Climb Bio Conference Call Company Overview - **Company**: Climb Bio - **Focus**: Development of monoclonal antibodies for autoimmune diseases, specifically targeting CD19 and APRIL Key Milestones and Upcoming Data - **2026**: Significant year for Climb Bio with multiple data readouts expected - **Budoprutug (CD19 monoclonal antibody)**: - Data from subcutaneous (subQ) formulation in healthy volunteers expected in the first half of 2026 - Data for ITP (Immune Thrombocytopenic Purpura) and SLE (Systemic Lupus Erythematosus) in the second half of 2026 - **Climb 116 (anti-APRIL for IgA nephropathy)**: - Healthy volunteer data anticipated mid-2026 - Focus on potential best-in-class assets for rare autoimmune diseases [2][10][27] Differentiation and Market Opportunity - **CD19 Antibody**: - High affinity for CD19, allowing for broader patient access - Only two monoclonal antibodies targeting CD19 in clinical development: Oplinza and Budoprutug - Oplinza has been successful but focuses on rare neurological diseases, leaving a gap in B-cell mediated diseases [4][5][6] - **IgA Nephropathy**: - Approximately 70,000 patients with no approved therapies, presenting a significant commercial opportunity - Current off-label use of Rituximab shows low efficacy (12%-14% complete renal response at 12 months) [10][11][37] Clinical Development Strategy - **Phase Two Study**: Initiated for PMN (Primary Membranous Nephropathy) with guidance on additional milestones forthcoming - **Indication Strategy**: Focus on high unmet needs in ITP and SLE, with a cautious approach to moving forward based on data [7][8][12] - **SLE Program**: Requires significant investment for late-phase development, with a focus on safety and potential immune reset in patients [16][17] Dosing and Formulation - **Dosing Strategy**: Careful selection of doses based on recent learnings from other CD19 programs, aiming for deep B-cell depletion rather than just peripheral suppression [19][21] - **SubQ Formulation**: Expected to be ready for phase three studies across all indications, optimizing patient access and market potential [22][23] Financial Overview - **Cash Position**: $176 million at the end of Q3, providing a runway through 2027, covering all data releases in 2026 [36] Regulatory Path and Study Size - **Regulatory Clarity**: Established path for PMN with a focus on complete renal response as a registrational endpoint - **Study Size**: Approximately 150 patients for PMN, manageable for a company of Climb Bio's size [37][38] Investor Interest - Growing interest in both Budoprutug and Climb 116, with investors recognizing the competitive profiles of both drugs in their respective markets [35]

Core Insights - Telitacicept achieved a 55% reduction in 24-hour urine protein-to-creatinine ratio (24h-UPCR) at 39 weeks compared to placebo, demonstrating significant clinical benefits in treating IgA nephropathy (IgAN) [1][3] - The Phase 3 clinical study in China met its primary endpoint and showed statistically significant improvements across all key secondary endpoints, indicating telitacicept's potential as a foundational therapy for B-cell mediated diseases [2][4] Group 1: Clinical Study Results - The Phase 3 study was a multicenter, randomized, double-blind, placebo-controlled trial involving 318 adult patients with IgAN at high risk of progression [2][5] - Telitacicept demonstrated a significant reduction in 24h-UPCR (-58.9% vs. -8.8%, p<0.0001) and stabilized kidney function, with a change in estimated glomerular filtration rate (eGFR) showing a decline in the placebo group (-0.77) compared to stabilization in the telitacicept group (-0.10) [3][5] - 61% of patients on telitacicept achieved 24h-UPCR <0.8 g/g compared to 19.5% on placebo, indicating a lower risk of disease progression [5] Group 2: Safety Profile - Telitacicept exhibited a favorable safety profile, with treatment-emergent adverse events occurring in 89.3% of patients compared to 78.6% in the placebo group; however, serious adverse events were less frequent with telitacicept (2.5% vs. 8.2%) [6] Group 3: Regulatory and Market Potential - RemeGen has submitted a Biologics License Application (BLA) to the National Medical Products Administration (NMPA) in China for telitacicept in treating IgAN, which could mark its fifth approved indication in the country [7][10] - Vor Bio is focused on advancing telitacicept through Phase 3 clinical development to address serious autoantibody-driven conditions globally [8][9]