Organization and Nature of Business	3 Months Ended
Mar. 31, 2026
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Nature of Business	Organization and Nature of Business Immuneering Corporation, a Delaware corporation (“Immuneering” or the “Company”), was incorporated in 2008. Immuneering is a late-stage clinical oncology company seeking to develop medicines for broad populations of cancer patients, with an initial aim to therapeutically address patients harboring RAS and/or RAF mutations. The Company aims to achieve broad activity through Deep Cyclic Inhibition® ("DCI") of the mitogen-activated protein kinase ("MAPK") pathway, impacting cancer cells while sparing healthy cells. Immuneering’s lead product candidate, atebimetinib (also referred to as IMM-1-104), is currently in a Phase 1/2a clinical trial in patients with advanced solid tumors harboring RAS or RAF mutations. The Company is developing atebimetinib as a once-daily oral therapy, aiming for activity through DCI of the MAPK pathway at the level of mitogen-activated protein kinase kinase ("MEK"). The Company’s development pipeline also includes early-stage programs. On October 30, 2019, Immuneering formed a wholly owned subsidiary, Immuneering Securities Corporation (“ISC”), a Massachusetts securities corporation, for the sole purpose of buying, selling and holding securities on the Company’s behalf. On December 22, 2021, the Company acquired all outstanding shares of capital stock of BioArkive, Inc. (“BioArkive”), a California corporation, which as a result became a wholly owned subsidiary. Immuneering, ISC and BioArkive are collectively referred to as the “Company” throughout these interim condensed consolidated financial statements. The Company is subject to a number of inherent risks associated with any biotechnology company that has substantial expenditures for research and development. These risks include, but are not limited to, the need to obtain adequate additional funding, possible failure of clinical trials or other events demonstrating lack of clinical safety or efficacy of its product candidates, dependence on key personnel, reliance on third-party service providers for manufacturing drug product and conducting clinical trials, the ability to successfully secure its proprietary technology, and risks related to the regulatory approval and commercialization of a product candidate. There can be no assurance that the Company’s research and development programs will be successful. In addition, the Company operates in an environment of rapid technological change and is largely dependent on the services of its employees, advisors, and consultants. On August 10, 2022, the Company entered into an Equity Distribution Agreement (the "2022 Sales Agreement") with Piper Sandler & Co (the "Sales Agent"), to sell shares of its common stock with aggregate gross proceeds of up to $50 million, from time to time, through an “at the market” equity offering program (the "2022 ATM Program"). The Company did not sell any shares of common stock under the 2022 ATM Program during the three months ended March 31, 2026. The Company sold 4,836,804 shares of common stock under the 2022 ATM Program, at a weighted average price per share of $2.95, for aggregate gross proceeds of $14.2 million ($13.7 million net of offering expenses) during the three months ended March 31, 2025. On April 20, 2023, the Company completed an underwritten follow-on equity offering, pursuant to which it issued and sold 2,727,273 shares of its Class A common stock $0.001 par value per share at an offering price of $11.00 per share. The aggregate net proceeds received by the Company from the offering were $28,200,003, after deducting underwriting discounts and commissions, but before deducting offering costs payable by the Company of $203,768. On August 13, 2025, the Company entered into an Equity Distribution Agreement (the "2025 Sales Agreement") with the Sales Agent, to sell shares of its common stock with aggregate gross proceeds of up to $100 million, from time to time, through an “at the market” equity offering program (the "2025 ATM Program"). In connection with the September 2025 Offering (as defined below), the Company: (i) reduced the maximum aggregate offering price for sales of shares of common stock pursuant to at-the-market transactions under the 2025 ATM Program by $1,250,007 (the "Reduced Amount"), resulting in a new maximum aggregate offering price of up to $98,749,993 under the 2025 ATM Program, and (ii) suspended the 2025 ATM Program and terminated the continuous offering under the 2025 ATM Program, in each case, as to the Reduced Amount. The Company did not sell any shares of common stock under the 2025 ATM Program during the three months ended March 31, 2026 or March 31, 2025, respectively. On August 21, 2025, the Company entered into a Securities Purchase Agreement (the "August 2025 Purchase Agreement") with the purchasers party thereto, pursuant to which the Company agreed to sell securities to such purchasers in a private placement (the “August 2025 Private Placement”). The August 2025 Purchase Agreement provided for the sale and issuance by the Company to the purchasers of: (i) an aggregate of 5,251,349 shares of its common stock at a purchase price of $3.95 per share, (ii) for certain purchasers, in lieu of common stock, an aggregate of 1,077,764 pre-funded warrants (the “Pre-Funded Warrants”) to purchase up to the same number of shares of its common stock, and (iii) an aggregate of 2,848,096 warrants (the “Purchase Warrants”) to purchase up to the same number of shares of its common stock. The Pre-Funded Warrants were issued for a purchase price equating to $3.949 per Pre-Funded Warrant (which was the per share purchase price for the common stock issued in the August 2025 Private Placement, less the $0.001 per share unfunded exercise price for each Pre-Funded Warrant). On October 6, 2025, certain purchasers from the August 2025 Private Placement exercised an aggregate of 1,077,764 Pre-Funded Warrants previously issued to them pursuant to the August 2025 Purchase Agreement. Each such exercise was made pursuant to the cashless exercise provision of the applicable Pre-Funded Warrant, such that an aggregate of 166 shares of common stock were withheld in lieu of cash payment of the $0.001 exercise price for each Pre-Funded Warrant share, and the exercising purchasers were issued an aggregate of 1,077,598 shares of common stock (the "October 2025 Cashless Exercise"). Following the October 2025 Cashless Exercise, no Pre-Funded Warrants remained issued and outstanding. The Purchase Warrants were issued with an exercise price of $5.50 per share; as of March 31, 2026, no Purchase Warrants had been exercised. As of March 31, 2026, the Company had received aggregate net proceeds of $23.4 million from the August 2025 Private Placement, after deducting placement expenses of $1.6 million. The August 2025 Private Placement closed on August 26, 2025. On September 24, 2025, the Company entered into a Securities Purchase Agreement (the "September 2025 Purchase Agreement") with Aventis Inc. ("Aventis"), a wholly owned subsidiary of Sanofi, a French société anonyme ("Sanofi"), pursuant to which the Company agreed to sell securities to Aventis in a private placement (the “September 2025 Private Placement”). The September 2025 Purchase Agreement provided for the sale and issuance by the Company to Aventis of an aggregate of 2,708,559 shares of its common stock at a purchase price of $9.23 per share. The Company received aggregate net proceeds of $23.4 million from the September 2025 Private Placement, after deducting placement agent discounts and commissions of $1.5 million and placement costs of $0.1 million. The September 2025 Private Placement closed on September 26, 2025. On September 26, 2025, the Company completed an underwritten follow-on equity offering, pursuant to which it issued and sold 18,959,914 shares of its Class A common stock at an offering price of $9.23 per share (the "September 2025 Offering"), with Leerink Partners LLC and Oppenheimer & Co. Inc. acting as underwriters. The aggregate net proceeds received by the Company from the September 2025 Offering were $164.1 million, after deducting underwriting discounts and commissions, as well as offering costs of $0.4 million. To date, the Company has primarily funded its operations with proceeds from the sale of its capital stock, warrants to purchase stock, and convertible notes. The Company has incurred recurring losses over the past several years and as of March 31, 2026, the Company had an accumulated deficit of $293.8 million. The Company expects to continue to generate operating losses for the foreseeable future. The future viability of the Company is dependent on its ability to raise additional capital to finance its operations. The Company’s inability to raise capital as and when needed could have a negative impact on its financial condition and ability to pursue its business strategies. There can be no assurances that additional funding will be available on terms acceptable to the Company, or at all. If the Company is unable to raise additional funds when needed, it may be required to delay, reduce the scope of, or eliminate development programs, which may adversely affect its business and operations. Management considered whether or not there are conditions or events, in the aggregate, that raise substantial doubt about the entity’s ability to continue as a going concern, and concluded that there are none as it estimates that its cash, cash equivalents and marketable securities will be sufficient to fund its operating expenses and capital expenditure requirements for at least 12 months from the issuance date of these unaudited condensed consolidated financial statements.

Immuneering Corporation, a Delaware corporation (“Immuneering” or the “Company”), was incorporated in 2008. Immuneering is a late-stage clinical oncology company seeking to develop medicines for broad populations of cancer patients, with an initial aim to therapeutically address patients harboring RAS and/or RAF mutations. The Company aims to achieve broad activity through Deep Cyclic Inhibition® ("DCI") of the mitogen-activated protein kinase ("MAPK") pathway, impacting cancer cells while sparing healthy cells. Immuneering’s lead product candidate, atebimetinib (also referred to as IMM-1-104), is currently in a Phase 1/2a clinical trial in patients with advanced solid tumors harboring RAS or RAF mutations. The Company is developing atebimetinib as a once-daily oral therapy, aiming for activity through DCI of the MAPK pathway at the level of mitogen-activated protein kinase kinase ("MEK"). The Company’s development pipeline also includes early-stage programs.

The Company is subject to a number of inherent risks associated with any biotechnology company that has substantial expenditures for research and development. These risks include, but are not limited to, the need to obtain adequate additional funding, possible failure of clinical trials or other events demonstrating lack of clinical safety or efficacy of its product candidates, dependence on key personnel, reliance on third-party service providers for manufacturing drug product and conducting clinical trials, the ability to successfully secure its proprietary technology, and risks related to the regulatory approval and commercialization of a product candidate. There can be no assurance that the Company’s research and development programs will be successful. In addition, the Company operates in an environment of rapid technological change and is largely dependent on the services of its employees, advisors, and consultants.

On August 10, 2022, the Company entered into an Equity Distribution Agreement (the "2022 Sales Agreement") with Piper Sandler & Co (the "Sales Agent"), to sell shares of its common stock with aggregate gross proceeds of up to $50 million, from time to time, through an “at the market” equity offering program (the "2022 ATM Program"). The Company did not sell any shares of common stock under the 2022 ATM Program during the three months ended March 31, 2026. The Company sold 4,836,804 shares of common stock under the 2022 ATM Program, at a weighted average price per share of $2.95, for aggregate gross proceeds of $14.2 million ($13.7 million net of offering expenses) during the three months ended March 31, 2025.

On April 20, 2023, the Company completed an underwritten follow-on equity offering, pursuant to which it issued and sold 2,727,273 shares of its Class A common stock $0.001 par value per share at an offering price of $11.00 per share. The aggregate net proceeds received by the Company from the offering were $28,200,003, after deducting underwriting discounts and commissions, but before deducting offering costs payable by the Company of $203,768.

On August 13, 2025, the Company entered into an Equity Distribution Agreement (the "2025 Sales Agreement") with the Sales Agent, to sell shares of its common stock with aggregate gross proceeds of up to $100 million, from time to time, through an “at the market” equity offering program (the "2025 ATM Program"). In connection with the September 2025 Offering (as defined below), the Company: (i) reduced the maximum aggregate offering price for sales of shares of common stock pursuant to at-the-market transactions under the 2025 ATM Program by $1,250,007 (the "Reduced Amount"), resulting in a new maximum aggregate offering price of up to $98,749,993 under the 2025 ATM Program, and (ii) suspended the 2025 ATM Program and terminated the continuous offering under the 2025 ATM Program, in each case, as to the Reduced Amount. The Company did not sell any shares of common stock under the 2025 ATM Program during the three months ended March 31, 2026 or March 31, 2025, respectively.

On August 21, 2025, the Company entered into a Securities Purchase Agreement (the "August 2025 Purchase Agreement") with the purchasers party thereto, pursuant to which the Company agreed to sell securities to such purchasers in a private placement (the “August 2025 Private Placement”). The August 2025 Purchase Agreement provided for the sale and issuance by the Company to the purchasers of: (i) an aggregate of 5,251,349 shares of its common stock at a purchase price of $3.95 per share, (ii) for certain purchasers, in lieu of common stock, an aggregate of 1,077,764 pre-funded warrants (the “Pre-Funded Warrants”) to purchase up to the same number of shares of its common stock, and (iii) an aggregate of 2,848,096 warrants (the “Purchase Warrants”) to purchase up to the same number of shares of its common stock. The Pre-Funded Warrants were issued for a purchase price equating to $3.949 per Pre-Funded Warrant (which was the per share purchase price for the common stock issued in the August 2025 Private Placement, less the $0.001 per share unfunded exercise price for each Pre-Funded Warrant). On October 6, 2025, certain purchasers from the August 2025 Private Placement exercised an aggregate of 1,077,764 Pre-Funded Warrants previously issued to them pursuant to the August 2025 Purchase Agreement. Each such exercise was made pursuant to the cashless exercise provision of the applicable Pre-Funded Warrant, such that an aggregate of 166 shares of common stock were withheld in lieu of cash payment of the $0.001 exercise price for each Pre-Funded Warrant share, and the exercising purchasers were issued an aggregate of 1,077,598 shares of common stock (the "October 2025 Cashless Exercise"). Following the October 2025 Cashless Exercise, no Pre-Funded Warrants remained issued and outstanding. The Purchase Warrants were issued with an exercise price of $5.50 per share; as of March 31, 2026, no Purchase Warrants had been exercised. As of March 31, 2026, the Company had received aggregate net proceeds of $23.4 million from the August 2025 Private Placement, after deducting placement expenses of $1.6 million. The August 2025 Private Placement closed on August 26, 2025.

On September 24, 2025, the Company entered into a Securities Purchase Agreement (the "September 2025 Purchase Agreement") with Aventis Inc. ("Aventis"), a wholly owned subsidiary of Sanofi, a French société anonyme ("Sanofi"), pursuant to which the Company agreed to sell securities to Aventis in a private placement (the “September 2025 Private Placement”). The September 2025 Purchase Agreement provided for the sale and issuance by the Company to Aventis of an aggregate of 2,708,559 shares of its common stock at a purchase price of $9.23 per share. The Company received aggregate net proceeds of $23.4 million from the September 2025 Private Placement, after deducting placement agent discounts and commissions of $1.5 million and placement costs of $0.1 million. The September 2025 Private Placement closed on September 26, 2025.

On September 26, 2025, the Company completed an underwritten follow-on equity offering, pursuant to which it issued and sold 18,959,914 shares of its Class A common stock at an offering price of $9.23 per share (the "September 2025 Offering"), with Leerink Partners LLC and Oppenheimer & Co. Inc. acting as underwriters. The aggregate net proceeds received by the Company from the September 2025 Offering were $164.1 million, after deducting underwriting discounts and commissions, as well as offering costs of $0.4 million.

To date, the Company has primarily funded its operations with proceeds from the sale of its capital stock, warrants to purchase stock, and convertible notes. The Company has incurred recurring losses over the past several years and as of March 31, 2026, the Company had an accumulated deficit of $293.8 million. The Company expects to continue to generate operating losses for the foreseeable future. The future viability of the Company is dependent on its ability to raise additional capital to finance its operations. The Company’s inability to raise capital as and when needed could have a negative impact on its financial condition and ability to pursue its business strategies. There can be no assurances that additional funding will be available on terms acceptable to the Company, or at all. If the Company is unable to raise additional funds when needed, it may be required to delay, reduce the scope of, or eliminate development programs, which may adversely affect its business and operations. Management considered whether or not there are conditions or events, in the aggregate, that raise substantial doubt about the entity’s ability to continue as a going concern, and concluded that there are none as it estimates that its cash, cash equivalents and marketable securities will be sufficient to fund its operating expenses and capital expenditure requirements for at least 12 months from the issuance date of these unaudited condensed consolidated financial statements.