Nature of the Business and Basis of Presentation	6 Months Ended
Jun. 30, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of the Business and Basis of Presentation	1. Nature of the Business and Basis of Presentation SQZ Biotechnologies Company (the “Company”) is a clinical-stage biotechnology company developing cell therapies for patients with cancer and other serious medical conditions. The Company uses its proprietary technology, Cell Squeeze, to physically squeeze cells through a microfluidic chip, temporarily opening the cell membrane and enabling biologic material of interest, or cargo, to diffuse into the cell. The Company is using Cell Squeeze technology to create multiple cell therapy platforms focused on directing specific immune responses. The Company was incorporated in March 2013 under the laws of the State of Delaware. The Company is subject to a number of risks and uncertainties common to early-stage companies in the biotechnology industry, including, but not limited to, development by competitors of new technological innovations, the ability to obtain additional financing, protection of proprietary technology, dependence on key personnel, the ability to attract and retain qualified employees, compliance with government regulations, the impact of overall economic conditions, and the clinical and commercial success of its product candidates. Product candidates currently under development will require significant additional research and development efforts, including extensive preclinical and clinical testing and regulatory approval prior to commercialization. These efforts require significant amounts of additional capital, adequate personnel and infrastructure and extensive compliance-reporting capabilities. Even if the Company’s drug development efforts are successful, it is uncertain when, if ever, the Company will realize significant revenue from product sales. Since inception, the Company has funded its operations primarily with payments received in connection with collaboration agreements, proceeds from equity and debt financing, and most recently, with proceeds from its 2020 initial public offering (“IPO”) and its 2021 follow-on offering (the "Follow-On Offering"), and an Open Market Sales Agreement (the "Sales Agreement"). On November 10, 2021, the Company entered into the Sales Agreement with Jefferies LLC (“Jefferies”) to issue and sell up to $75,000,000 in shares of the Company’s common stock from time to time during the term of the Sales Agreement through an “at-the-market” equity offering program under which Jefferies acts as the Company’s sales agent (the “ATM Facility”). The Company did not sell any shares under the ATM Facility during both the three and six months ended June 30, 2023. During the three and six months ended June 30, 2022, the Company sold 958,663 shares of common stock under the ATM Facility for net proceeds of approximately $3.1 million. Going Concern Assessment Management has assessed the Company’s ability to continue as a going concern in accordance with the requirements of ASC 205-40, taking into consideration its recurring losses from operations incurred since inception, expectation of continuing operating losses for the foreseeable future and the need to raise additional capital to finance future operations. Through June 30, 2023, the Company has funded its operations primarily with proceeds from sales of convertible preferred stock, payments received in connection with collaboration agreements, proceeds from borrowings under a convertible promissory note, which converted into shares of convertible preferred stock, and more recently the proceeds from its IPO, the Follow-On Offering and the ATM Facility. The Company has incurred recurring losses since inception, including a net loss of $34.5 million for the six months ended June 30, 2023. As of June 30, 2023, the Company had an accumulated deficit of $309.4 million. Based on its current cash expenditure forecast, the Company expects that its existing cash and cash equivalents will fund its operations through the end of 2023. The Company expects to continue to generate operating losses in the foreseeable future. As of August 10, 2023, the issuance date of the interim condensed consolidated financial statements for the three and six months ended June 30, 2023, the Company has concluded that there is substantial doubt about its ability to continue as a going concern for a period of one year from the date that these interim condensed consolidated financial statements are issued. The Company will require additional funding through private or public equity financings, debt financings, collaborations, strategic alliances and marketing, distribution or licensing arrangements. The Company may not be able to obtain financing on acceptable terms, or at all, and the Company may not be able to enter into collaborations or other arrangements. The terms of any financing may adversely affect the holdings or the rights of the Company's stockholders. The future viability of the Company is dependent on its ability to raise additional capital to finance its operations. If the Company is unable to obtain funding, the Company will be forced to incur additional restructuring costs, delay, reduce or eliminate some or all of its research and development programs, product portfolio expansion or commercialization efforts, which could adversely affect its business prospects, or the Company may be unable to continue operations. Although management continues to pursue these plans, there is no assurance that the Company will be successful in obtaining sufficient funding on terms acceptable to the Company to fund continuing operations, or at all. See Note 13, Subsequent Events. The Company has announced that it has determined to pursue potential strategic alternatives to support the advancement of its oncology and other programs, including HPV 16 positive tumors, in an effort to allow the Company to partner its clinical and preclinical assets across all disease areas and indications. Potential strategic partnerships may include, but are not limited to, a partnership, acquisition, merger, business combination, or other transaction. There can be no assurance that this process will result in the Company pursuing a transaction or that any transaction, if pursued, will be completed on attractive terms. The Company has not set a timetable for completion of this process and does not intend to comment further unless or until the Board of Directors has approved a definitive course of action, the process is concluded, or it is determined that other disclosure is appropriate. The accompanying interim condensed consolidated financial statements do not include any adjustments relating to the recoverability and classification of recorded asset amounts or the amounts and classification of liabilities that might result from the outcome of this uncertainty. Accordingly, the interim condensed consolidated financial statements have been prepared on a basis that assumes the Company will continue as a going concern and which contemplates the realization of assets and satisfaction of liabilities and commitments in the ordinary course of business. Impact of Macroeconomic Conditions The global economy, including credit and financial markets, has recently experienced extreme volatility and disruptions, including, for example, severely diminished liquidity and credit availability, rising interest and inflation rates, crises involving banking and financial institutions, declines in consumer confidence, declines in economic growth, increases in unemployment rates and uncertainty about economic stability. The Company is monitoring the potential impact of general economic conditions on its business and financial statements. To date, the Company has not incurred impairment losses in the carrying values of its assets as a result of general economic conditions and it is not aware of any specific related event or circumstance that would require it to revise its estimates reflected in these interim condensed consolidated financial statements. Unstable market and economic conditions or pandemics may have serious adverse consequences on the Company's business, financial condition and results of operations. Basis of Presentation The Company’s consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”). The accompanying interim condensed consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries, SQZ Biotechnologies Security Corporation, SQZ Biotech HK Limited and SQZ Biotech (Shanghai) Co., Ltd. All intercompany accounts and transactions have been eliminated in consolidation.

Nature of the Business and Basis of Presentation

6 Months Ended

Jun. 30, 2023

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Nature of the Business and Basis of Presentation

1. Nature of the Business and Basis of Presentation

SQZ Biotechnologies Company (the “Company”) is a clinical-stage biotechnology company developing cell therapies for patients with cancer and other serious medical conditions. The Company uses its proprietary technology, Cell Squeeze, to physically squeeze cells through a microfluidic chip, temporarily opening the cell membrane and enabling biologic material of interest, or cargo, to diffuse into the cell. The Company is using Cell Squeeze technology to create multiple cell therapy platforms focused on directing specific immune responses. The Company was incorporated in March 2013 under the laws of the State of Delaware.

The Company is subject to a number of risks and uncertainties common to early-stage companies in the biotechnology industry, including, but not limited to, development by competitors of new technological innovations, the ability to obtain additional financing, protection of proprietary technology, dependence on key personnel, the ability to attract and retain qualified employees, compliance with government regulations, the impact of overall economic conditions, and the clinical and commercial success of its product candidates. Product candidates currently under development will require significant additional research and development efforts, including extensive preclinical and clinical testing and regulatory approval prior to commercialization. These efforts require significant amounts of additional capital, adequate personnel and infrastructure and extensive compliance-reporting capabilities. Even if the Company’s drug development efforts are successful, it is uncertain when, if ever, the Company will realize significant revenue from product sales.

Since inception, the Company has funded its operations primarily with payments received in connection with collaboration agreements, proceeds from equity and debt financing, and most recently, with proceeds from its 2020 initial public offering (“IPO”) and its 2021 follow-on offering (the "Follow-On Offering"), and an Open Market Sales Agreement (the "Sales Agreement"). On November 10, 2021, the Company entered into the Sales Agreement with Jefferies LLC (“Jefferies”) to issue and sell up to $75,000,000 in shares of the Company’s common stock from time to time during the term of the Sales Agreement through an “at-the-market” equity offering program under which Jefferies acts as the Company’s sales agent (the “ATM Facility”). The Company did not sell any shares under the ATM Facility during both the three and six months ended June 30, 2023. During the three and six months ended June 30, 2022, the Company sold 958,663 shares of common stock under the ATM Facility for net proceeds of approximately $3.1 million.

Going Concern Assessment

Management has assessed the Company’s ability to continue as a going concern in accordance with the requirements of ASC 205-40, taking into consideration its recurring losses from operations incurred since inception, expectation of continuing operating losses for the foreseeable future and the need to raise additional capital to finance future operations. Through June 30, 2023, the Company has funded its operations primarily with proceeds from sales of convertible preferred stock, payments received in connection with collaboration agreements, proceeds from borrowings under a convertible promissory note, which converted into shares of convertible preferred stock, and more recently the proceeds from its IPO, the Follow-On Offering and the ATM Facility. The Company has incurred recurring losses since inception, including a net loss of $34.5 million for the six months ended June 30, 2023. As of June 30, 2023, the Company had an accumulated deficit of $309.4 million. Based on its current cash expenditure forecast, the Company expects that its existing cash and cash equivalents will fund its operations through the end of 2023.

The Company expects to continue to generate operating losses in the foreseeable future. As of August 10, 2023, the issuance date of the interim condensed consolidated financial statements for the three and six months ended June 30, 2023, the Company has concluded that there is substantial doubt about its ability to continue as a going concern for a period of one year from the date that these interim condensed consolidated financial statements are issued. The Company will require additional funding through private or public equity financings, debt financings, collaborations, strategic alliances and marketing, distribution or licensing arrangements. The Company may not be able to obtain financing on acceptable terms, or at all, and the Company may not be able to enter into collaborations or other arrangements. The terms of any financing may adversely affect the holdings or the rights of the Company's stockholders. The future viability of the Company is dependent on its ability to raise additional capital to finance its operations. If the Company is unable to obtain funding, the Company will be forced to incur additional restructuring costs, delay, reduce or eliminate some or all of its research and development programs, product portfolio expansion or commercialization efforts, which could adversely affect its business prospects, or the Company may be unable to continue operations. Although management continues to pursue these plans, there is no assurance that the Company will be successful in obtaining sufficient funding on terms acceptable to the Company to fund continuing operations, or at all. See Note 13, Subsequent Events.

The Company has announced that it has determined to pursue potential strategic alternatives to support the advancement of its oncology and other programs, including HPV 16 positive tumors, in an effort to allow the Company to partner its clinical and preclinical assets across all disease areas and indications. Potential strategic partnerships may include, but are not limited to, a partnership, acquisition, merger, business combination, or other transaction. There can be no assurance that this process will result in the Company pursuing a

transaction or that any transaction, if pursued, will be completed on attractive terms. The Company has not set a timetable for completion of this process and does not intend to comment further unless or until the Board of Directors has approved a definitive course of action, the process is concluded, or it is determined that other disclosure is appropriate.

The accompanying interim condensed consolidated financial statements do not include any adjustments relating to the recoverability and classification of recorded asset amounts or the amounts and classification of liabilities that might result from the outcome of this uncertainty. Accordingly, the interim condensed consolidated financial statements have been prepared on a basis that assumes the Company will continue as a going concern and which contemplates the realization of assets and satisfaction of liabilities and commitments in the ordinary course of business.

Impact of Macroeconomic Conditions

The global economy, including credit and financial markets, has recently experienced extreme volatility and disruptions, including, for example, severely diminished liquidity and credit availability, rising interest and inflation rates, crises involving banking and financial institutions, declines in consumer confidence, declines in economic growth, increases in unemployment rates and uncertainty about economic stability. The Company is monitoring the potential impact of general economic conditions on its business and financial statements. To date, the Company has not incurred impairment losses in the carrying values of its assets as a result of general economic conditions and it is not aware of any specific related event or circumstance that would require it to revise its estimates reflected in these interim condensed consolidated financial statements. Unstable market and economic conditions or pandemics may have serious adverse consequences on the Company's business, financial condition and results of operations.

Basis of Presentation

The Company’s consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”).

The accompanying interim condensed consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries, SQZ Biotechnologies Security Corporation, SQZ Biotech HK Limited and SQZ Biotech (Shanghai) Co., Ltd. All intercompany accounts and transactions have been eliminated in consolidation.

SQZ Biotechnologies Co 10-Q