SQZ Biotechnologies Reports Third Quarter 2023 Financial Results and Recent Portfolio Updates

• SQZ^® AAC Phase 1 Trial Observed Best Overall Response (BOR) of Stable Disease or Better in 60 Percent (3 of 5) of Treated Patients, Including One Patient with a Confirmed Complete Response
• SQZ^® eAPC Phase 1/2 Trial Monotherapy Observed BOR of Stable Disease in 40 Percent (8 of 20) of Treated Patients
• Reduced Workforce by Approximately 80 Percent Based on Cost-Reduction Initiatives to Lower the Company’s Ongoing Operating Expenses While it Pursues Strategic Alternatives

WATERTOWN, Mass.WATERTOWN, Mass.--(BUSINESS WIRE)--SQZ Biotechnologies Company (OTC: SQZB), focused on unlocking the full potential of cell therapies, today reported third quarter 2023 financial results and recent portfolio updates.

“We have taken difficult, but necessary, steps to reduce our operating expenses as we explore strategic alternatives,” said Howard Bernstein, M.D., Ph.D., Interim Chief Executive Officer and Member of the Board of Directors. “The Management Team and the Board firmly believe in the technology and therapeutic potential and are committed to exploring a variety of potential paths.”

Third Quarter 2023 and Recent Portfolio Updates

Clinical Programs:

SQZ^® Activating Antigen Carriers (“AAC”) Platform in Oncology

• Of the five patients treated, 1 patient experienced a complete response and 2 patients experienced stable disease
• Interim clinical data reported at the Society for Immunotherapy of Cancer (SITC) Annual Meeting 2023

SQZ^® Enhanced Antigen Presenting Cell (“eAPC”) Platform in Oncology

• Completed enrollment for highest-dose cohort of monotherapy dose escalation trial
• Observed BOR of Stable Disease in 40 Percent (8 of 20) of Treated Patients
• Interim clinical data reported at the SITC Annual Meeting 2023

Corporate:

• The Company is actively seeking potential partnerships, collaborations and strategic alternatives to advance its oncology programs and platforms
• On September 29, 2023, the Board of Directors of SQZ approved a reduction in the Company’s workforce by approximately 80 percent. The decision was based on cost-reduction initiatives intended to reduce the Company’s ongoing operating expenses while it pursues strategic alternatives

Third Quarter 2023 Financial Highlights

• Revenue for the quarter ended September 30, 2023, was $0.0 compared to $3.5 million for the same period in 2022
• Research and development expenses for the quarter ended September 30, 2023, were $10.5 million compared to $19.6 million for the same period in 2022
• General and administrative expenses for the quarter ended September 30, 2023, were $5.6 million compared to $6.9 million for the same period in 2022
• Restructuring charges for the quarter ended September 30, 2023 were $7.7 million, driven primarily by a non-cash impairment charge to its facility right of use asset
• Net loss for the quarter ended September 30, 2023, was $23.6 million, compared to $22.6 million for the same period in 2022
• As of September 30, 2023, the Company had cash and cash equivalents of $10.2 million

About SQZ Biotechnologies

SQZ Biotechnologies is a clinical-stage biotechnology company focused on unlocking the full potential of cell therapies. The Company’s proprietary Cell Squeeze® technology offers the unique ability to deliver multiple biological materials into many patient cell types to engineer what the Company believes can be a broad range of potential therapeutics. The Company’s goal is to create well-tolerated cell therapies that can provide therapeutic benefit for patients and improve the patient experience over existing cell therapy approaches. With production timelines under 24 hours and the opportunity to eliminate preconditioning and lengthy hospital stays, the Company believes its approach could change the way people think about cell therapies. For more information, please visit www.sqzbiotech.com.

Forward Looking Statements

This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Such statements are based upon current plans, estimates and expectations of management that are subject to various risks and uncertainties that could cause actual results to differ materially from such statements. The inclusion of forward-looking statements should not be regarded as a representation that such plans, estimates and expectations will be achieved. Words such as “anticipate,” “expect,” “project,” “intend,” “believe,” “may,” “will,” “should,” “plan,” “could,” “may,” “continue,” “target,” “contemplate,” “estimate,” “forecast,” “guidance,” “predict,” “possible,” “potential,” “pursue,” “likely,” and similar expressions are intended to identify forward-looking statements, though not all forward-looking statements use these words or expressions. All statements, other than historical facts, including statements regarding the Company’s clinical execution, exploration of strategic alternatives, restructuring initiatives and other cost savings measures, are forward-looking statements. These forward-looking statements are based on management's current expectations. Actual results could differ from those projected in any forward-looking statements due to several risk factors, including but not limited to the important factors discussed under the caption "Risk Factors" in the Company’s Annual Report on Form 10-K for the year ended December 31, 2022, and its other filings with the U.S. Securities and Exchange Commission. Any forward-looking statements represent management's estimates as of this date and the Company undertakes no duty to update these forward-looking statements, whether as a result of new information, the occurrence of current events, or otherwise, unless required by law.

investors@sqzbiotech.com