Nature of Operations and Basis of Presentation	6 Months Ended
Jun. 30, 2025
Accounting Policies [Abstract]
Nature of Operations and Basis of Presentation	1. Nature of Operations and Basis of Presentation Organization Climb Bio, Inc. (the Company), is a clinical-stage biotechnology company developing therapeutics for patients with immune-mediated diseases. The Company’s pipeline includes budoprutug and CLYM116. Budoprutug is an anti-CD19 monoclonal antibody designed to treat a broad range of B-cell mediated diseases. The Company is currently developing budoprutug for the treatment of primary membranous nephropathy, immune thrombocytopenia, and systemic lupus erythematosus. CLYM116 is an anti-APRIL (A Proliferation-Inducing Ligand) monoclonal antibody currently being developed for the treatment of immunoglobulin A nephropathy. The Company was incorporated on October 18, 2018 in Delaware, and its corporate headquarters are in Massachusetts. On June 27, 2024, the Company completed its acquisition of Tenet Medicines, Inc. (the Acquisition). In connection with the closing of the Acquisition, the Company issued and sold 31,238,282 shares of its common stock at a price of $3.84 per share in a private placement to several accredited institutional investors (the Private Placement). The Company received aggregate gross proceeds from the Private Placement of approximately $120.0 million, before deducting offering costs of $0.3 million (see Note 3). On January 8, 2025, the Company entered into a technology transfer and exclusive license agreement (the Mabworks Agreement) with Beijing Mabworks Biotech Co., Ltd. (Mabworks), for rights to develop and commercialize CLYM116 for all indications worldwide outside of mainland China, Hong Kong, Macau, and Taiwan (Greater China) (see Note 7). Risks and Uncertainties The Company is subject to risks and uncertainties common to early-stage companies in the biotechnology industry, including, but not limited to, development by competitors of new technological innovations, protection of proprietary technology, dependence on key personnel, reliance on single-source suppliers and manufacturers, availability of raw materials, patentability of the Company’s product candidates and processes and clinical efficacy and safety of the Company’s product candidates, compliance with government regulations and the need to obtain additional financing to fund operations. Budoprutug, CLYM116, or any product candidate the Company may develop will require significant additional research and development efforts, including extensive preclinical studies, clinical trials, and regulatory approval, prior to commercialization. These efforts will require significant amounts of additional capital, adequate personnel infrastructure and extensive compliance and reporting. There can be no assurance that any future research and development will be successfully completed, that adequate protection for the Company’s intellectual property will be obtained or maintained, that any product candidates developed will obtain necessary government regulatory approval or that any approved products will be commercially viable. Even if any future product development efforts are successful, it is uncertain when, if ever, the Company will generate revenue from product sales. The Company operates in an environment of rapid technological change and substantial competition from other pharmaceutical and biotechnology companies. In addition, the Company is dependent upon the services of its employees, consultants and other third parties. Basis of Presentation and Principles of Consolidation The accompanying unaudited interim condensed consolidated financial statements reflect the operations of the Company and its wholly owned subsidiaries. Intercompany transactions and balances have been eliminated in consolidation. The accompanying unaudited interim condensed consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States (U.S. GAAP) and in accordance with the rules and regulations of the U.S. Securities and Exchange Commission (SEC) for Quarterly Reports on Form 10-Q. Any reference in these notes to applicable guidance is meant to refer to the authoritative U.S. GAAP as found in the Accounting Standards Codification (ASC) and Accounting Standards Update (ASU) of the Financial Accounting Standards Board (FASB). The accompanying condensed consolidated financial statements as of June 30, 2025 and for the three and six months ended June 30, 2025 and 2024, are unaudited. The consolidated balance sheet as of December 31, 2024 was derived from the audited financial statements as of and for the year ended December 31, 2024, but does not include all disclosures required by U.S. GAAP. The unaudited interim condensed consolidated financial statements have been prepared on a basis consistent with the audited annual financial statements as of and for the year ended December 31, 2024, and, in the opinion of management, reflect all adjustments, consisting solely of normal recurring adjustments, necessary for the fair statement of the Company’s financial position as of June 30, 2025, the condensed results of its operations for the three and six months ended June 30, 2025 and 2024, and its cash flows for the six months ended June 30, 2025 and 2024. The financial data and other information disclosed in these notes related to the three and six months ended June 30, 2025 and 2024 are also unaudited. The condensed results of operations for the three and six months ended June 30, 2025 are not necessarily indicative of the results to be expected for the full year ending December 31, 2025 or any other period. These unaudited interim condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements included in the Company’s Annual Report on Form 10-K filed with the SEC on March 25, 2025. Liquidity Since inception, the Company has experienced recurring losses from operations and generated negative cash flows from operations. The Company has an accumulated deficit of $259.3 million as of June 30, 2025 and expects to incur additional losses from operations in the future. In March 2025, the Company entered into an Equity Distribution Agreement (the Distribution Agreement) with Oppenheimer & Co. Inc., as agent (Oppenheimer), pursuant to which the Company may offer and sell shares of its common stock from time to time through Oppenheimer having an aggregate offering price of up to $22.4 million in an at the market offering. During the three and six months ended June 30, 2025, the Company did not issue and sell any shares of its common stock pursuant to the Distribution Agreement. The Company believes its available cash, cash equivalents and marketable securities of $187.4 million as of June 30, 2025 will be sufficient to meet its projected operating requirements for at least the next twelve months from the filing date of these unaudited condensed consolidated financial statements, and the Company anticipates that it will need to raise substantial financing in the future to fund its operations. The Company may finance future cash needs through the sale of equity, debt financings or other capital sources, which could include income from collaborations, strategic partnerships or other strategic arrangements. There are no assurances that the Company will be able to raise sufficient amounts of funding in the future on acceptable terms, or at all.

Climb Bio, Inc. (the Company), is a clinical-stage biotechnology company developing therapeutics for patients with immune-mediated diseases. The Company’s pipeline includes budoprutug and CLYM116. Budoprutug is an anti-CD19 monoclonal antibody designed to treat a broad range of B-cell mediated diseases. The Company is currently developing budoprutug for the treatment of primary membranous nephropathy, immune thrombocytopenia, and systemic lupus erythematosus. CLYM116 is an anti-APRIL (A Proliferation-Inducing Ligand) monoclonal antibody currently being developed for the treatment of immunoglobulin A nephropathy. The Company was incorporated on October 18, 2018 in Delaware, and its corporate headquarters are in Massachusetts.

On June 27, 2024, the Company completed its acquisition of Tenet Medicines, Inc. (the Acquisition). In connection with the closing of the Acquisition, the Company issued and sold 31,238,282 shares of its common stock at a price of $3.84 per share in a private placement to several accredited institutional investors (the Private Placement). The Company received aggregate gross proceeds from the Private Placement of approximately $120.0 million, before deducting offering costs of $0.3 million (see Note 3).

On January 8, 2025, the Company entered into a technology transfer and exclusive license agreement (the Mabworks Agreement) with Beijing Mabworks Biotech Co., Ltd. (Mabworks), for rights to develop and commercialize CLYM116 for all indications worldwide outside of mainland China, Hong Kong, Macau, and Taiwan (Greater China) (see Note 7).

The Company is subject to risks and uncertainties common to early-stage companies in the biotechnology industry, including, but not limited to, development by competitors of new technological innovations, protection of proprietary technology, dependence on key personnel, reliance on single-source suppliers and manufacturers, availability of raw materials, patentability of the Company’s product candidates and processes and clinical efficacy and safety of the Company’s product candidates, compliance with government regulations and the need to obtain additional financing to fund operations. Budoprutug, CLYM116, or any product candidate the Company may develop will require significant additional research and development efforts, including extensive preclinical studies, clinical trials, and regulatory approval, prior to commercialization. These efforts will require significant amounts of additional capital, adequate personnel infrastructure and extensive compliance and reporting.

There can be no assurance that any future research and development will be successfully completed, that adequate protection for the Company’s intellectual property will be obtained or maintained, that any product candidates developed will obtain necessary government regulatory approval or that any approved products will be commercially viable. Even if any future product development efforts are successful, it is uncertain when, if ever, the Company will generate revenue from product sales. The Company operates in an environment of rapid technological change and substantial competition from other pharmaceutical and biotechnology companies. In addition, the Company is dependent upon the services of its employees, consultants and other third parties.

Basis of Presentation and Principles of Consolidation

The accompanying unaudited interim condensed consolidated financial statements reflect the operations of the Company and its wholly owned subsidiaries. Intercompany transactions and balances have been eliminated in consolidation. The accompanying unaudited interim condensed consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States (U.S. GAAP) and in accordance with the rules and regulations of the U.S. Securities and Exchange Commission (SEC) for Quarterly Reports on Form 10-Q. Any reference in these notes to applicable guidance is meant to refer to the authoritative U.S. GAAP as found in the Accounting Standards Codification (ASC) and Accounting Standards Update (ASU) of the Financial Accounting Standards Board (FASB).

The accompanying condensed consolidated financial statements as of June 30, 2025 and for the three and six months ended June 30, 2025 and 2024, are unaudited. The consolidated balance sheet as of December 31, 2024 was derived from the audited financial statements as of and for the year ended December 31, 2024, but does not include all disclosures required by U.S. GAAP. The unaudited interim condensed consolidated financial statements have been prepared on a basis consistent with the audited annual financial statements as of and for the year ended December 31, 2024, and, in the opinion of management, reflect all adjustments, consisting solely of normal recurring adjustments, necessary for the fair statement of the Company’s financial position as of June 30, 2025, the condensed results of its operations for the three and six months ended June 30, 2025 and 2024, and its cash flows for the six months ended June 30, 2025 and 2024. The financial data and other information disclosed in these notes related to the three and six months ended June 30, 2025 and 2024 are also unaudited. The condensed results of operations for the three and six months ended June 30, 2025 are not necessarily indicative of the results to be expected for the full year ending December 31, 2025 or any other period. These unaudited interim condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements included in the Company’s Annual Report on Form 10-K filed with the SEC on March 25, 2025.

Since inception, the Company has experienced recurring losses from operations and generated negative cash flows from operations. The Company has an accumulated deficit of $259.3 million as of June 30, 2025 and expects to incur additional losses from operations in the future. In March 2025, the Company entered into an Equity Distribution Agreement (the Distribution Agreement) with Oppenheimer & Co. Inc., as agent (Oppenheimer), pursuant to which the Company may offer and sell shares of its common stock from time to time through Oppenheimer having an aggregate offering price of up to $22.4 million in an at the market offering. During the three and six months ended June 30, 2025, the Company did not issue and sell any shares of its common stock pursuant to the Distribution Agreement.

The Company believes its available cash, cash equivalents and marketable securities of $187.4 million as of June 30, 2025 will be sufficient to meet its projected operating requirements for at least the next twelve months from the filing date of these unaudited condensed consolidated financial statements, and the Company anticipates that it will need to raise substantial financing in the future to fund its operations. The Company may finance future cash needs through the sale of equity, debt financings or other capital sources, which could include income from collaborations, strategic partnerships or other strategic arrangements. There are no assurances that the Company will be able to raise sufficient amounts of funding in the future on acceptable terms, or at all.