SQZ Biotechnologies Reports Data for Clinical Programs at the Society for Immunotherapy of Cancer Annual Meeting

SQZ Biotechnologies Company (OTC: SQZB), focused on unlocking the full potential of cell therapies, presented clinical data for three programs focused on the treatment of Human Papillomavirus 16 positive (HB16+) driven cancers at the Society for Immunotherapy of Cancer Annual Meeting 2023.

"Our programs have shown a favorable safety profile and the ability to effect clinical benefit for patients," said Howard Bernstein, M.D., Ph.D., Interim Chief Executive Officer and Member of the Board of Directors. "While these results are early, the management team and the board of directors are encouraged by the potential of Cell Squeeze^® based therapeutics and are committed to exploring strategic alternatives for the company and its proprietary technology."

Key findings:

SQZ^® Activating Antigen Carriers ("AAC") Platform in Oncology
Poster# 693: SQZ-AAC-HPV-101: Initial data from a phase I dose escalation/expansion study of SQZ-AAC-HPV, a red blood cell-based therapeutic cancer vaccine for HPV16+ solid tumors

• Of the five patients treated, one patient experienced a confirmed complete response and two patients experienced stable disease
• SQZ-AAC-HPV monotherapy is considered generally safe and well-tolerated at all dose levels

SQZ^® Enhanced Antigen Presenting Cell ("eAPC") Platform in Oncology
Poster# 692: COMMANDER-001: Safety data from a phase I/II dose escalation/expansion study of SQZ-eAPC-HPV, a cell-based mRNA therapeutic cancer vaccine for HPV16+ solid tumors

• 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
• SQZ-eAPC-HPV monotherapy is considered generally safe and well-tolerated at all dose levels

SQZ^® Antigen Presenting Cell ("APC") Platform in Oncology:
Poster# 594: SQZ-PBMC-HPV-101: Increased overall survival in a subset of patients with recurrent, locally advanced, or metastatic HPV16+ tumors treated with cell-based vaccine, SQZ-PBMC-HPV

• A subset of patients with paired biopsies (6 of 18) showed increased CD8 T cell infiltration when compared to baseline
  • These patients with increased CD8 T cell infiltration demonstrated an improved overall survival ("OS") when compared to patients with decreased CD8 T cell infiltration
  • Median OS [95% CI) for Increase in CD8: 606.5 days [314.0, 713.0] compared to median OS [95% CI) for Decrease in CD8: 170.0 days [54.0, 220.0]
• SQZ-PBMC-HPV monotherapy is considered generally safe and well-tolerated at all dose levels

About Human Papillomavirus Positive Cancers

Human papillomavirus (HPV) is one of the most common viruses worldwide and certain strains persist for many years, often leading to cancer. According to the Centers for Disease Control (CDC), in the United States HPV+ tumors represent 3% of all cancers in women and 2% of all cancers in men, resulting in over 39,000 new cases of HPV+ tumors every year. HPV infection is larger outside of the U.S., and according to the International Journal of Cancer, HPV+ tumors account for 4.5% of all cancers worldwide resulting in approximately 630,000 new cases every year. According to the CDC, HPV infection plays a significant role in the formation of more than 90% of anal and cervical cancers, and most cases of vaginal (75%), oropharyngeal (70%), vulval (70%) and penile (60%) cancers.

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 clinical outcomes, profile and benefits of our clinical candidates, and exploration of strategic alternatives 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.