Summary of Climb Bio's Conference Call Company Overview - **Company**: Climb Bio - **Focus**: Autoimmune diseases with two antibodies in clinical development Key Points Upcoming Milestones - Climb Bio has five clinical data readouts scheduled for this year - Monoclonal antibody targeting CD19: - Data on subcutaneous (subQ) formulation in healthy volunteers expected in the first half of the year - Initial data from Phase 1b studies in Immune Thrombocytopenic Purpura (ITP) and Systemic Lupus Erythematosus (SLE) in the second half - Initial data from Phase 2 study in Primary Membranous Nephropathy (PMN) also expected in the second half - Second antibody, an APRIL-only antibody for IgA nephropathy, will have data available mid-year [2][3][4] Competitive Landscape - UPLIZNA is currently the only approved CD19 antibody, focusing on rare neuro diseases - Climb Bio's CD19 antibody is believed to have greater affinity and a subQ formulation option, which UPLIZNA lacks [5][7][11] PMN Indication - No approved therapies currently exist for PMN; standard care includes off-label use of rituximab - Rituximab achieves complete renal remission in only 10% of patients after one year and 35% after two years - Climb Bio's Phase 1b study showed a 60% complete remission rate and 100% serological remission in PLA2R antibody-positive patients [14][15][32] Market Opportunity - Approximately 70,000 patients in the U.S. have PMN, with two-thirds requiring therapeutic intervention - Regulatory strategy involves one Phase 3 study with around 150 patients, focusing on proteinuria as the primary endpoint [32][34] ITP and SLE Indications - ITP has a strong rationale for CD19 targeting, with only 20% of refractory patients achieving a durable platelet response - SLE is viewed as a more complex indication, requiring larger pivotal trials; Climb Bio is conducting a parallel study in China for lupus nephritis patients [39][40][41] APRIL Antibody Development - Climb Bio's APRIL-only antibody (CLYM116) features a unique sweeper mechanism, allowing for high-affinity binding and potential for longer half-life - Early studies indicate a two- to threefold longer half-life compared to existing therapies, with better activity in IgA suppression [48][56][60] Financial Position - Climb Bio reported $176 million in cash at the end of Q3, with a runway extending into 2028, covering all planned readouts for the year [93][95] Future Indications - Climb Bio is exploring additional indications for the APRIL antibody, including Sjögren's syndrome, to maximize asset potential [90][91] Conclusion - Climb Bio is positioned to address significant unmet needs in autoimmune diseases with promising clinical data and a strong financial foundation, paving the way for potential market success in the coming years [2][93][95]

Core Insights - Climb Bio, Inc. has made significant progress in its clinical development programs for budoprutug and CLYM116, with multiple trials ongoing and initial data expected in 2026 [2][3][4] Group 1: Budoprutug Program - Budoprutug, an anti-CD19 monoclonal antibody, has initiated a Phase 2 trial in Primary Membranous Nephropathy (pMN) with first patient dosing achieved in November 2025 [4] - The Phase 1b/2a trial in Immune Thrombocytopenia (ITP) is ongoing, focusing on safety, tolerability, and preliminary efficacy [4] - A global Phase 1b trial in Systemic Lupus Erythematosus (SLE) is also underway, with regulatory clearance for a parallel trial in China received in December 2025 [4][11] - Budoprutug has shown long-term control of proteinuria in pMN patients, as presented at the 2025 ASN Kidney Week [4] Group 2: CLYM116 Program - CLYM116, an anti-APRIL monoclonal antibody, has initiated a Phase 1 study in healthy volunteers, with initial data expected in mid-2026 [8][11] - The antibody targets APRIL, a key driver of B-cell activity in autoimmune diseases, and employs a novel mechanism for enhanced efficacy [13] Group 3: Financial Position and Strategic Priorities - Climb Bio maintains a strong financial position, with cash runway expected to extend into 2028 [2][6] - The company has achieved 20 regulatory clearances for clinical trials and activated 45 trial sites globally, indicating robust clinical execution [3] - 2026 is anticipated to be a transformative year with multiple data readouts from ongoing trials, addressing unmet needs in renal and B-cell mediated diseases [3][4]

Core Insights - Climb Bio Inc. (NASDAQ:CLYM) is identified as a promising biotech penny stock, with analysts projecting a price target increase from $9 to $11 while maintaining a Buy rating due to anticipated data readouts in 2026 for its lead asset Budoprutug [1][2] Group 1: Company Overview - Climb Bio is a clinical-stage biotechnology company focused on developing therapies for immune-mediated diseases, primarily through its two main assets: Budoprutug and CLYM116 [2][5] - Budoprutug is an anti-CD19 antibody targeting B-cell mediated diseases, while CLYM116 is an anti-APRIL antibody aimed at treating IgA nephropathy [2] Group 2: Clinical Trials and Data Readouts - The company has initiated the PrisMN Phase 2 trial for Budoprutug in Primary Membranous Nephropathy, with the trial designed to evaluate safety, pharmacokinetics, and preliminary efficacy, aiming for data release in 2026 [3] - A Phase 1 trial for a subcutaneous formulation of Budoprutug is currently ongoing, with initial data expected in the first half of 2026 [3] - Climb Bio is also conducting an open-label Phase 1b/2a trial for Budoprutug in patients with Immune Thrombocytopenia and a Phase 1b trial in Systemic Lupus Erythematosus patients, with preliminary efficacy results anticipated in the second half of 2026 [4]

Core Insights - Climb Bio Inc. (CLYM) is set for a data-rich year in 2026, with study results from its key programs expected to influence its strategic direction and future development phases [1] Drug Candidates - Budoprutug is an anti-CD19 monoclonal antibody designed for potent and durable B cell depletion, with both intravenous (IV) and subcutaneous (SC) administration options. It is being investigated for primary membranous nephropathy, immune thrombocytopenia, and systemic lupus erythematosus [2] - CLYM116 is a novel anti-APRIL monoclonal antibody aimed at promoting the degradation of APRIL, targeting B-cell-mediated diseases such as systemic lupus erythematosus, myasthenia gravis, and IgA nephropathy [3] Ongoing Trials & Upcoming Catalysts - A phase 2 study named PrisMN is evaluating Budoprutug's safety and efficacy in adult subjects with primary membranous nephropathy, enrolling 45 subjects and expected to complete in 2027 [4] - A phase 1b/2a study is assessing Budoprutug in immune thrombocytopenia, with initial efficacy data anticipated in the second half of 2026 [6] - A phase 1b study is evaluating Budoprutug in systemic lupus erythematosus, with preliminary efficacy data expected in the second half of 2026 [8] - A phase 1 study for the SC formulation of Budoprutug in healthy volunteers is ongoing, with initial data expected in the first half of 2026 [10] - Regulatory clearance for a phase 1 trial of CLYM116 has been obtained, with dosing expected to start by the end of 2025 and initial data anticipated mid-2026 [10] Financial Position - As of September 30, 2025, the company reported cash, cash equivalents, and marketable securities totaling $175.8 million, which is sufficient to fund operations through 2027 [11] Company Background - Climb Bio, formerly Eliem Therapeutics, went public on August 10, 2021, under the ticker symbol "ELYM" at an IPO price of $12.50 per share. The company rebranded to Climb Bio, Inc. and changed its ticker symbol to "CLYM" on October 3, 2024, reflecting a strategic focus on immune-mediated diseases [12] - CLYM's stock has traded between $1.05 and $3.25 over the past year, closing at $3.00 on December 12, 2025, representing a 30.43% increase [13]

Core Insights - Climb Bio, Inc. has initiated a Phase 2 trial of budoprutug for Primary Membranous Nephropathy (pMN) and expects to advance its clinical programs significantly in 2026 [1][2] - The company has strengthened its leadership team with key appointments to enhance operational capabilities [1][11] - Financial results indicate a cash position that is expected to sustain operations through 2027, allowing for continued development of its clinical pipeline [1][8] Budoprutug Program Updates - The Phase 2 trial, named 'PrisMN,' has been initiated in multiple countries, focusing on safety, pharmacokinetics, and preliminary efficacy [5] - A Phase 1 trial of a subcutaneous formulation of budoprutug is ongoing, with initial data expected in H1 2026 [1][5] - Ongoing trials for budoprutug in Immune Thrombocytopenia (ITP) and Systemic Lupus Erythematosus (SLE) are expected to yield initial data in H2 2026 [1][5] CLYM116 Program Updates - CLYM116, targeting the APRIL pathway for IgA nephropathy, has received regulatory clearance for a Phase 1 trial, with dosing anticipated by year-end 2025 [1][6] - Initial data from the CLYM116 trial is expected in mid-2026, following a recent R&D Spotlight Webcast that highlighted its differentiation from first-generation therapies [6][2] Financial Performance - As of September 30, 2025, the company reported cash, cash equivalents, and marketable securities totaling $175.8 million, expected to fund operations through 2027 [1][11] - Research and Development (R&D) expenses for Q3 2025 were $9.1 million, an increase from $6.2 million in Q3 2024, while General and Administrative (G&A) expenses were $5.8 million, slightly up from $5.5 million in the prior year [8][11]

Core Insights - Climb Bio, Inc. has appointed Adam Villa as Senior Vice President of Technical Operations and Ashley Jones as Senior Vice President of People & Workforce Strategy, enhancing its leadership team during a critical growth phase [2][4]. Leadership Appointments - Adam Villa brings over 20 years of experience in biopharmaceutical development and manufacturing, with expertise in technical operations and clinical production scaling. His previous roles include Vice President of CMC at Generation Bio and leadership positions at CRISPR Therapeutics and Biogen [2][3]. - Ashley Jones has nearly 20 years of experience in the biotechnology sector, previously founding Cultivate Co. and holding leadership roles at Ananke Therapeutics, Imara, and SQZ Biotechnologies. She is recognized for building high-performing organizations and fostering collaborative cultures [3][2]. Inducement Equity Awards - Climb Bio granted inducement equity awards to the new executives, consisting of non-statutory stock options to purchase up to 360,000 shares of common stock at an exercise price of $2.32 per share. The options have a ten-year term and vest over four years [4]. Company Overview - Climb Bio, Inc. is a clinical-stage biotechnology company focused on developing therapeutics for immune-mediated diseases. Its pipeline includes budoprutug, an anti-CD19 monoclonal antibody, and CLYM116, an anti-APRIL monoclonal antibody for IgA nephropathy [5].

Core Insights - Climb Bio, Inc. is advancing two monoclonal antibodies, CLYM116 for IgA nephropathy and budoprutug for primary membranous nephropathy, with promising preclinical and clinical data to be presented at the 2025 ASN Kidney Week [1][2][3] Group 1: CLYM116 Development - CLYM116 is a novel anti-APRIL monoclonal antibody designed to treat IgA nephropathy, showing favorable pharmacokinetic and pharmacodynamic profiles in preclinical models [1][2] - The antibody promotes APRIL degradation and enhances antibody recycling, leading to significant reductions in IgA levels [2][9] - CLYM116 employs a pH-dependent binding mechanism, potentially allowing for less frequent dosing and a favorable safety profile [9] Group 2: Budoprutug Clinical Data - Budoprutug is an anti-CD19 monoclonal antibody targeting B-cell mediated diseases, with long-term follow-up data from a Phase 1b trial indicating sustained control of proteinuria for up to three years in patients with primary membranous nephropathy [3][7] - In the trial, four patients received up to four doses of budoprutug, with three patients not requiring further immunosuppressive treatment [3] - No significant treatment-related adverse events were reported, supporting further investigation of budoprutug as a potential disease-modifying therapy [3][8] Group 3: Presentation Details - Climb Bio will present CLYM116 data at ASN Kidney Week on November 8, 2025, with a poster titled "Development and Characterization of CLYM116" [5] - The abstract for budoprutug's long-term remission data in primary membranous nephropathy is also available, highlighting its clinical significance [5][4]

Core Viewpoint - Climb Bio, Inc. has appointed Susan Altschuller, Ph.D., MBA, as Chief Financial Officer, enhancing its leadership team to support the advancement of its therapeutic pipeline for immune-mediated diseases [1][2][3] Company Leadership - Susan Altschuller brings over 20 years of strategic and financial leadership experience in the biopharmaceutical sector, having previously served as CFO at Cerevel Therapeutics and ImmunoGen [2][3] - Her expertise includes financial strategy, capital allocation, and operational execution, which will be valuable as Climb Bio progresses with its clinical programs [2][3] Clinical Pipeline - Climb Bio is advancing two key programs: budoprutug, an anti-CD19 monoclonal antibody, and CLYM116, an anti-APRIL monoclonal antibody for IgA nephropathy [4] - The company anticipates generating significant clinical data from both programs in the upcoming year, which will inform future strategies [2][3] Inducement Equity Award - In connection with her appointment, Climb Bio granted Dr. Altschuller an inducement equity award consisting of a non-statutory stock option to purchase up to 600,000 shares of common stock, with a ten-year term and a four-year vesting schedule [3]

CLYM116 & IgAN Opportunity - Climb Bio's mission is to deliver high impact, disease-modifying medicines for individuals living with immune-mediated diseases[5] - CLYM116 is an anti-APRIL monoclonal antibody being developed for IgA Nephropathy (IgAN)[8, 48] - Climb Bio has worldwide rights to CLYM116 outside Greater China, partnering with Beijing Mabworks Biotech Co, Ltd[9, 11] - Phase 1 initiation of CLYM116 is expected in Q4 2025, with initial data anticipated mid-year 2026[8, 15, 16, 106] IgAN Market & Treatment Landscape - IgAN represents a significant market opportunity estimated at ~$10-20 billion in the US, with most patients requiring lifelong treatment[12, 105] - KDIGO 2025 guidelines recommend treatment initiation for patients with proteinuria >=05 g/day, representing approximately 60-75% of patients[13] - The FDA recognizes the need for surrogate outcomes, such as improvement in proteinuria, in IgAN studies for accelerated approval[29] CLYM116 Differentiated Profile - CLYM116 is the only known "sweeper" anti-APRIL mAb in development, designed for improved activity, less frequent dosing, and a favorable safety profile[10, 57, 103, 106] - Preclinical NHP data demonstrated potential for deep and durable IgA suppression, with >70% maximal reduction after a single 6 mg/kg SC dose, and a ~2-3x longer half-life compared to sibeprenlimab[16, 74, 84, 89, 90, 104] - In NHPs, CLYM116 SC demonstrated high bioavailability of ~85% and favorable tolerability, supporting potential for convenient, at-home dosing[81]

Core Insights - Climb Bio, Inc. announced promising preclinical data for CLYM116, an anti-APRIL monoclonal antibody, showing deeper IgA reduction and a longer half-life compared to the first-generation antibody sibeprenlimab [1][3][4] Company Developments - CLYM116 is set to enter a Phase 1 trial in healthy volunteers, expected to begin in Q4 2025, with initial biomarker and dosing interval data anticipated by mid-2026 [1][5][7] - The company is hosting a virtual investor event on September 29, 2025, featuring nephrologist Craig E. Gordon, who has extensive experience in treating IgA nephropathy [2][3] Product Profile - CLYM116 is characterized as a "sweeper" anti-APRIL monoclonal antibody, demonstrating a subcutaneous formulation with high bioavailability (~85%) and a favorable tolerability profile [7][10] - The antibody exhibits a 2-3 times longer half-life compared to sibeprenlimab and achieves over 70% maximal reduction in IgA after a single administration at equivalent doses [7][10] Market Opportunity - IgA nephropathy (IgAN) represents a significant market opportunity, estimated at $10-20 billion in the U.S. alone, with a high unmet need for effective treatments [6][12] - The updated KDIGO 2025 guidelines emphasize the need for more active management of IgAN, potentially expanding the market opportunity for CLYM116 [3][12] Clinical Context - IgAN is the most common primary glomerular disease worldwide, affecting approximately 170,000 patients in the U.S. and typically requiring lifelong management [12] - The KDIGO guidelines recommend stricter proteinuria control and highlight the importance of reducing pathogenic IgA, positioning anti-APRIL therapy as a core treatment approach for IgAN [12]