A2 Biotherapeutics, Inc.

Six abstracts accepted for presentation to provide updates on ongoing clinical trials and adaptations to boost potency and preserve selectivity of Tmod TM -based precision cell therapies Update on BASECAMP-1 prescreening trial abstract accepted for oral presentation AGOURA HILLS, Calif.--(BUSINESS WIRE)--A2 Biotherapeutics, Inc. (A2 Bio), a clinical-stage cell therapy company developing first-in-class logic-gated cell therapies to selectively target tumor cells and protect normal cells, today announced the acceptance of six abstracts for presentation during the 39 th Annual Meeting of the Society for Immunotherapy of Cancer (SITC) taking place November 8-10, 2024, in Houston. The company will share an oral presentation that details continued progress to enhance the diversity of patients enrolled in its BASECAMP-1 prescreening trial. Additional posters will present safety and biomarker data in the EVEREST-1 trial; continued progress in the ongoing EVEREST-2 clinical trial; and adaptations to boost potency and preserve selectivity of Tmod TM -based cell therapies. The accepted abstracts are available online on the SITC website . Oral Presentation Details Presentation Title: “BASECAMP-1 is an efficient pre-screening study that identifies patients with HLA LOH and provides mutational, RNA-Seq, and microbiome data for precision logic-gated CAR T therapeutic trials” Session Title: Cellular Therapies - Financial Toxicities, Access to Care Session Date/Time: Saturday, Nov. 9, 5:15-6:35pm CDT Session Room: George R. Brown Convention Center - Level 3 - Grand Ballroom B Final Abstract Number: 589 Presenting Author: Julian Molina, M.D., Ph.D., Mayo Clinic Poster Presentation Details Abstract Title Author Abstract Number Poster Presentation Date Poster Presentation Location EVEREST-1: Initial safety data from a seamless phase 1/2 study of A2B530, a logic-gated Tmod CAR T-cell therapy, in patients with solid tumors associated with CEA expression also exhibiting HLA-LOH Patrick Grierson Washington University 588 Saturday, November 9, 9am-8:30pm Exhibit Halls A B George R. Brown Convention Center BASECAMP-1 is an efficient pre-screening study that identifies patients with HLA LOH and provides mutational, RNA-Seq, and microbiome data for precision logic-gated CAR T therapeutic trials Julian Molina Mayo Clinic 589 Friday, November 8, 9am-7pm EVEREST-2: A seamless phase 1/2 study of A2B694, a logic-gated Tmod CAR T-cell therapy, in patients with solid tumors with human leukocyte antigen-A*02 loss of heterozygosity Julian Molina Mayo Clinic 627 Onboard, tethered cytokines boost potency and maintain selectivity of a Tmod NOT gate Jingli Zhang A2 Biotherapeutics 341 Functional screen to optimize logic gate potency and selectivity Sara Martire A2 Biotherapeutics 292 Saturday, November 9, 9am-8:30pm Signal 1 boosters for Tmod: addressing the next obstacle in cell therapy for solid tumors Julie Oh A2 Biotherapeutics 302 About EVEREST-1 EVEREST-1 ( NCT05736731 ) is a seamless Phase 1/2 study for A2B530, an autologous logic-gated investigational cell therapy developed from the A2 Bio proprietary Tmod™ platform. The Tmod™ platform provides selective killing of tumor cells and protection of normal cells via a dual-receptor design consisting of an activator that targets tumor cells and a blocker that protects normal cells. A2B530 consists of an activator that targets carcinoembryonic antigen (CEA) and a blocker that targets HLA-A*02. HLA-A*02 is lost in tumor cells and present in normal cells in the eligible patient population. The study is recruiting participants with non-small cell lung, colorectal and pancreatic cancers. About EVEREST-2 EVEREST-2 ( NCT06051695 ) is a seamless Phase 1/2 study for A2B694, an autologous logic-gated investigational cell therapy developed from the A2 Bio proprietary Tmod™ platform. The Tmod™ platform provides selective killing of tumor cells and protection of normal cells via a dual-receptor design consisting of an activator that targets tumor cells and a blocker that protects normal cells. A2B694 consists of an activator that targets mesothelin (MSLN) and a blocker that targets HLA-A*02. HLA-A*02 is lost in tumor cells and present in normal cells in the eligible patient population. The study is recruiting participants with non-small cell lung, colorectal, pancreatic, ovarian and mesothelioma cancers. About BASECAMP-1 BASECAMP-1 ( NCT04981119 ) is a prescreening study to identify patients for potential treatment in A2 Bio clinical trials. It is a novel approach to help optimize patient treatment outcomes by enabling patients’ immune cells to be banked in their healthiest state earlier in their course of cancer treatment. Next-generation sequencing is used to identify patients who have lost HLA-A*02, the biomarker of interest for the A2 Bio studies. Patients then undergo leukapheresis to collect, process, and store patient T cells for future Tmod™ CAR T cell therapy. BASECAMP-1 is currently enrolling participants with non-small cell lung, colorectal, pancreatic, ovarian and mesothelioma cancers. About the Tmod™ Platform A2 Bio has pioneered a precision-targeting cellular system – the Tmod™ platform – that incorporates two receptors, an activator and a blocker, to aim the powerful armaments of immune cells directly at tumors to unequivocally differentiate tumors from normal tissues. The activator recognizes antigens on tumor cells that trigger their destruction, while the blocker recognizes antigens on normal cells that protect them. This novel blocker technology enables precise, personalized and effective T cell targeting. The blocker component equips Tmod™ cells with the capacity to identify tumors as distinct from normal cells. About A2 Bio A2 Biotherapeutics, Inc. (A2 Bio) is a clinical-stage biotech company developing first-in-class logic-gated cell therapies to address the high unmet need in cancers. A2 Bio invented the proprietary Tmod™ cell therapy platform to tackle the fundamental challenge in cancer treatment—the ability of cancer medicines to distinguish between tumor and normal cells. For more information, please visit the company’s website at . Contacts Mary-Frances Faraji Jeff Winton Associates maryfrances@jeffwintonassociates.com 908-334-7693

CHICAGO--( BUSINESS WIRE )--Tempus AI, Inc. (NASDAQ: TEM), a technology company leading the adoption of AI to advance precision medicine and patient care, today announced that the validation study of its human leukocyte antigen (HLA) loss of heterozygosity (LOH) investigational assay has been published in npj Precision Oncology . Titled, “ Detecting HLA loss of heterozygosity within a standard diagnostic sequencing workflow for prognostic and therapeutic opportunities ,” the study included analytical validation of an investigational test that detects HLA-LOH based on analysis of data generated from Tempus’ FDA-approved, next generation sequencing-based xT CDx assay. The test uses a machine learning model to analyze sequenced data produced by Tempus’ xT CDx assay to identify patients with solid tumors that have experienced allele-specific LOH for specific HLA Class I alleles and may benefit from treatment with specific, targeted therapies. The study evaluated the test’s ability to accurately detect HLA-LOH in clinical samples with >=40% tumor cells. In collaboration with A2 Biotherapeutics, Tempus analyzed data from an observational clinical trial ( NCT04981119 ), and demonstrated the feasibility of identifying HLA-LOH patients and accruing them into prospective studies by leveraging analysis of routinely obtained clinical diagnostic data. Results support the assay's use as an investigational device for precision oncology clinical trial use. “Tempus’ HLA-LOH test is particularly significant for use in clinical trials that apply cell therapy to solid tumors, and it also has wider implications for precision medicine, including its use alongside other established biomarkers,” said Kate Sasser, PhD, Chief Scientific Officer at Tempus. “As validated in this study, the HLA-LOH test may help identify patients most likely to benefit from new and exciting therapies.” In 2023, the U.S. Food & Drug Administration (FDA) granted Breakthrough Device Designation for the use of Tempus’ HLA-LOH assay as a companion diagnostic test. The HLA-LOH assay is an investigational device that is not currently available for clinical use. About Tempus Tempus is a technology company advancing precision medicine through the practical application of artificial intelligence in healthcare. With one of the world’s largest libraries of multimodal data, and an operating system to make that data accessible and useful, Tempus provides AI-enabled precision medicine solutions to physicians to deliver personalized patient care and in parallel facilitates discovery, development and delivery of optimal therapeutics. The goal is for each patient to benefit from the treatment of others who came before by providing physicians with tools that learn as the company gathers more data. For more information, visit tempus.com. About xT CDx xT CDx is a qualitative Next Generation Sequencing (NGS)-based in vitro diagnostic device intended for use in the detection of substitutions (single nucleotide variants (SNVs) and multi-nucleotide variants (MNVs)) and insertion and deletion alterations (INDELs) in 648 genes, as well as microsatellite instability (MSI) status, using DNA isolated from formalin-fixed paraffin embedded (FFPE) tumor tissue specimens, and DNA isolated from matched normal blood or saliva specimens, from previously diagnosed cancer patients with solid malignant neoplasms. The test is intended as a companion diagnostic (CDx) to identify patients who may benefit from treatment with the targeted therapies listed in the Companion Diagnostic Indications table in accordance with the approved therapeutic product labeling. Additionally, xT CDx is intended to provide tumor mutation profiling to be used by qualified health care professionals in accordance with professional guidelines in oncology for patients with previously diagnosed solid malignant neoplasms. Genomic findings other than those listed in the Companion Diagnostic Indications table are not prescriptive or conclusive for labeled use of any specific therapeutic product. xT CDx is a single-site assay performed at Tempus AI, Inc., Chicago, IL. For the complete xT CDx label, including Companion Diagnostic Indications table and important risk information, please visit https://www.tempus.com/resources/document-library/tempus-xt-cdx_technical-information/ . Forward Looking Statements This press release contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended (the “Securities Act”), and Section 21E of the Securities Exchange Act of 1934, as amended, about Tempus and Tempus’ industry that involve substantial risks and uncertainties. All statements other than statements of historical facts contained in this press release are forward-looking statements, including, but not limited to, statements regarding the quality of this study; the contributions of this study to the larger scientific community, and the use of Tempus’ products and services to advance clinical care for patients. In some cases, you can identify forward-looking statements because they contain words such as “anticipate,” “believe,” “contemplate,” “continue,” “could,” “estimate,” “expect,” “going to,” “intend,” “may,” “plan,” “potential,” “predict,” “project,” “should,” “target,” “will,” or “would” or the negative of these words or other similar terms or expressions. Tempus cautions you that the foregoing may not include all of the forward-looking statements made in this press release. You should not rely on forward-looking statements as predictions of future events. Tempus has based the forward-looking statements contained in this press release primarily on its current expectations and projections about future events and trends that it believes may affect Tempus’ business, financial condition, results of operations and prospects. These forward-looking statements are subject to risks and uncertainties related to: Tempus’ financial performance; the ability to attract and retain customers and partners; managing Tempus’ growth and future expenses; competition and new market entrants; compliance with new laws, regulations and executive actions, including any evolving regulations in the artificial intelligence space; the ability to maintain, protect and enhance Tempus’ intellectual property; the ability to attract and retain qualified team members and key personnel; the ability to repay or refinance outstanding debt, or to access additional financing; future acquisitions, divestitures or investments; the potential adverse impact of climate change, natural disasters, health epidemics, macroeconomic conditions, and war or other armed conflict, as well as risks, uncertainties, and other factors described in the section titled “Risk Factors” in Tempus’ Quarterly Report on Form 10-Q for the quarter ended June 30, 2024 filed with the Securities and Exchange Commission (“SEC”) as well as in other filings Tempus may make with the SEC in the future. In addition, any forward-looking statements contained in this press release are based on assumptions that Tempus believes to be reasonable as of this date. Tempus undertakes no obligation to update any forward-looking statements to reflect events or circumstances after the date of this press release or to reflect new information or the occurrence of unanticipated events, except as required by law.

Presentations Detail Ongoing CEA and Mesothelin Phase 1/2 Clinical Trials In Progress Evaluating Investigational Tmod™ CAR T-Cell Therapies for Patients with Solid Tumors Additional Poster Demonstrates Impact of Expanded Biomarker Prescreening to Improve Diversity in Clinical Trials CHICAGO--(BUSINESS WIRE)-- A2 Biotherapeutics , Inc. (A2 Bio), a clinical-stage cell therapy company developing first-in-class logic-gated cell therapies for solid tumors, will present updates on three ongoing clinical trials in poster presentations during the 2024 American Society of Clinical Oncology (ASCO) Annual Meeting. A2 Bio will present two Trials in Progress posters on its first-in-human (FIH) Phase 1/2 studies, EVEREST-1 and EVEREST-2, as well as a poster highlighting how a greater understanding of the structure of Tmod™ allowed the BASECAMP-1 master prescreening study to increase the ethnic and racial diversity of patients enrolled in its clinical trials. “Diversity in clinical studies is essential to address racial and ethnic groups who are often underrepresented in clinical trials, especially in precision medicine studies using genetic data. We are creating the future of precision medicine by applying advanced bioinformatics in our BASECAMP-1 prescreening protocol to efficiently screen patients for enrollment in these ongoing CAR T-cell clinical trials. Expanding the enrollment criteria to include all HLA-A*02 patients will further enhance the diversity in our trial,” said Julian R. Molina, M.D., Ph.D., Professor of Oncology, Mayo Clinic, Rochester, MN. Significant challenges remain in harnessing the potential of cell-based therapies due to a lack of tumor‑specific targets that discriminate cancer from normal cells, resulting in on‑target, off‑tumor toxicity. The investigational therapies being studied by A2 Bio in EVEREST-1 (A2B530 targeting carcinoembryonic antigen [CEA]) and EVEREST-2 (A2B694 targeting mesothelin [MSLN]) apply the company’s proprietary Tmod™ platform which utilizes a dual-receptor design consisting of an activator that targets tumor cells and a blocker that protects normal cells to provide selective tumor killing.1 “We are encouraged by the clinical trial progress presented during ASCO 2024. A2 Bio is advancing the clinical development of our innovative CAR T-cell therapies and pioneering a new model for enhancing safety, efficiency and diversity in our interventional trials, and therefore addressing important unmet medical needs,” said William Go, M.D., Ph.D., chief medical officer of A2 Bio. The poster presentations are scheduled on Saturday, June 1, 9:00 am – 12:00 pm CT. EVEREST-1 (NCT05736731) is a FIH study evaluating A2B530 in patients with solid tumors that express CEA and have human leukocyte antigen (HLA)-A*02 loss of heterozygosity (LOH). The first patient in EVEREST-1 was dosed in May 2023 and dose escalation continues, with 10 patients treated to date. EVEREST-2 (NCT06051695) is also a FIH study evaluating A2B694 in patients with solid tumors that express MSLN and have HLA-A*02 LOH. The first patient was dosed in May 2024 in this study to evaluate the safety and efficacy of A2B694. BASECAMP-1 (NCT04981119) is a master prescreening, precision medicine study identifying patients with unresectable, advanced or metastatic solid tumors with HLA-A*02 LOH; patients undergo leukapheresis and Tmod™ CAR T cells are manufactured for patients who may enroll in the ongoing EVEREST-1 and EVEREST-2 clinical trials. BASECAMP-1 enrollment began with screening for patients with the HLA-A*02:01 allele only. Nonclinical testing determined that the Tmod™ blocker was effective against other HLA-A*02:XX alleles, and enrollment was expanded to patients with any HLA-A*02 allele subtype. Because HLA-A*02:XX subtypes are more prevalent in non-whites, this change improved the racial and ethnic diversity of the BASECAMP-1 study population. By expanding enrollment, 16% more Hispanic, 43% more African-American, and 112% more Asian or Pacific Islander patients were identified. For more information on A2 Bio clinical trials, please visit About the Tmod™ Platform A2 Bio has pioneered a precision-targeting cellular system – the Tmod™ mechanism – that incorporates two receptors, an activator and a blocker, to aim the powerful armaments of immune cells directly at tumors to unequivocally differentiate tumors from normal tissues. The activator recognizes antigens on tumor cells that trigger their destruction, while the blocker recognizes antigens on normal cells that protect them. This novel blocker technology enables precise, personalized and effective T cell targeting. The blocker component equips Tmod™ cells with the capacity to identify tumors as distinct from normal cells. About EVEREST-1 EVEREST-1 (NCT05736731) is a seamless Phase 1/2 study for A2B530, an autologous logic-gated investigational cell therapy developed from A2 Bio’s proprietary Tmod™ platform. The Tmod™ platform provides selective killing of tumor cells and protection of normal cells via a dual-receptor design consisting of an activator that targets tumor cells and a blocker that protects normal cells. A2B530 consists of an activator that targets carcinoembryonic antigen (CEA) and a blocker that targets HLA-A*02. HLA-A*02 is lost in tumor cells and present in normal cells in the eligible patient population. The study is recruiting patients with non-small cell lung, colorectal and pancreatic cancers. About EVEREST-2 EVEREST-2 (NCT06051695) is a seamless Phase 1/2 study for A2B694, an autologous logic-gated investigational cell therapy developed from A2 Bio’s proprietary Tmod™ platform. The Tmod™ platform provides selective killing of tumor cells and protection of normal cells via a dual-receptor design consisting of an activator that targets tumor cells and a blocker that protects normal cells. A2B694 consists of an activator that targets mesothelin (MSLN) and a blocker that targets HLA-A*02. HLA-A*02 is lost in tumor cells and present in normal cells in the eligible patient population. The study is recruiting patients with non-small cell lung, colorectal, pancreatic, ovarian and mesothelioma cancers. About BASECAMP-1 BASECAMP-1 (NCT04981119) is a prescreening study to identify patients for potential treatment in A2 Bio’s clinical trials. It is a novel approach to help optimize patient treatment outcomes by enabling patients' immune cells to be banked in their healthiest state earlier in their course of cancer treatment. Next-generation sequencing is used to identify patients who have lost HLA-A*02, the biomarker of interest for A2 Bio’s studies. Patients then undergo leukapheresis to collect, process, and store patient T cells for future Tmod™ CAR T cell therapy. BASECAMP-1 is currently enrolling patients with non-small cell lung, colorectal, pancreatic, ovarian and mesothelioma cancers. About A2 Biotherapeutics A2 Biotherapeutics, Inc. (A2 Bio) is a clinical-stage biotech company developing first-in-class logic-gated cell therapies to address the high unmet need in cancers. A2 Bio invented the proprietary Tmod™ cell therapy platform to tackle the fundamental challenge in cancer treatment—the ability of cancer medicines to distinguish between tumor and normal cells. For more information, please visit the company’s website at . References: 1 Breanna DiAndreth, Agnes E. Hamburger, Han Xu, Alexander Kamb: The Tmod cellular logic gate as a solution for tumor-selective immunotherapy. Clinical Immunology, Volume 241, 2022, 109030.