PACT Reports New Data on First-of-its-Kind Personalized Neoantigen Platform for Adoptive T Cell Therapies at American Association for Cancer Research (AACR) Annual Meeting 2022

Ongoing Phase 1 Clinical Trial Has Provided New Data Sets for Analysis of T Cell Receptor (TCR) Landscape of Tumor-Specific T Cells in Human Cancers

Study Findings Being Leveraged to Enhance Company's T Cell Therapy Platform Including Predictive PACTImmune™ Database and Novel PACT^{^}NV™ Non-Viral Gene Editing Technology

SOUTH SAN FRANCISCO, Calif., April 11, 2022 /PRNewswire/ -- PACT Pharma, Inc., a clinical-stage company developing transformational personalized neoantigen-specific T cell receptor (neoTCR) T cell therapies for the eradication of solid tumors, today announced that new data highlighting several aspects of its first-of-its-kind personalized neoantigen platform for adoptive cell therapies were presented in five separate poster presentations at the American Association for Cancer Research (AACR) Annual Meeting 2022. The breadth of presented data reflects the expansive collection of pioneering insights into patient-specific TCR repertoires against solid tumors that the company has been able to accumulate through analysis of research samples, as well as patient samples from its ongoing first-in-human Phase 1 trial. The AACR conference is being held April 8-13, 2022, in New Orleans, Louisiana.

"The scope of presented findings at AACR highlights the significant progress that we have made across all aspects of our unique neoTCR T cell therapy platform, spanning identification and verification of patient-specific tumor driving mutations, gene editing, cell manufacturing, machine learning and bioinformatics," said Stefanie Mandl, Ph.D., senior vice president, head of research at PACT Pharma. "This continued progress speaks to the dynamic research and development approach that we are undertaking at PACT, as we aggressively advance our clinical-stage assets in human studies while using the evolving data set and learnings from our Phase 1 trial to continue to enhance various aspects of our technology platforms. This constellation of activities is focused on the single goal of bringing much needed, first-of-its kind neoTCR T cell therapies to patients battling solid tumors."

PACT is currently conducting a Phase 1 clinical trial evaluating the safety, tolerability and feasibility of adoptive cell therapy with its non-viral PACT^{^}NV™ gene-edited autologous neoTCR T cells in advanced and metastatic solid tumors. This trial, in combination with extensive preclinical studies, has provided the company with unique data sets and insights derived from the core technologies that comprise its personalized adoptive T cell therapy platform for the treatment of solid tumors.

Key presented findings at AACR included:

imPACT Isolation Technology® Platform for TCR Discovery and Validation: Identifies TCRs to  Patient-Specific Tumor Driver Mutations

By applying its imPACT Isolation Technology® platform to peripheral blood samples of more than 170 patients with solid tumors, PACT generated key findings on the relative distribution of patient-private mutations versus mutations in known cancer driver genes. Data demonstrated that tumor-specific T cells preferentially recognize patient-private mutations. However, TCRs that target known cancer driver mutations were shown to constitute > 5% of the functionally characterized TCRs, highlighting a high-value opportunity for "off-the-shelf" TCR therapies. Based on these findings, PACT is expanding its platform to develop such "off-the-shelf" treatments, and anticipates filing an investigational new drug (IND) application in the second half of 2022.

Proprietary Machine Learning and Bioinformatics Optimize Personalized Treatment Strategies

In two separate AACR posters, PACT highlighted its continued work building and utilizing its PACTImmune™ Database with extensive pre-, on- and post-treatment data from its ongoing Phase 1 trial. Analysis of this maturing data set with proprietary machine learning and bioinformatics produced new insights into patient-specific tumor immunogenicity in solid cancers, providing opportunities to optimize personalized neoTCR T cell treatment. The company's application of its proprietary PACT-ESCAPE™ technology provided key learnings regarding neoepitope presentation escape mechanisms, which is a critical aspect of personalized TCR-based immunotherapy.

PACT^{^}NV™: Efficiently Enabling Single-Step Precision Gene Editing

In two separate poster presentations, PACT reported continued progress with PACT^{^}NV, the company's non-viral precision gene editing approach for generating clinical-grade TCR T cells for adoptive cell therapy. Importantly, the company has demonstrated the ability to execute precise, time-efficient, single-step gene editing to simultaneously knock-out TCR genes and insert neoantigen-specific TCRs isolated from a patient's own blood. Furthermore, the company described its success incorporating additional complex modifications, which are intended to address challenges presented by the immunosuppressive nature of some tumor microenvironments, into the single-step gene editing process.

Copies of the posters presented at the AACR conference are available on the "Events" page of the PACT Pharma website at: https://www.pactpharma.com/news/?filter=events.

About PACT Pharma, Inc.
PACT is a clinical-stage biopharmaceutical company pioneering individualized, non-viral precision genome engineered, tumor-specific T cell therapies for the treatment of patients with solid cancers. PACT is now enrolling patients in its first-in-human Phase 1 clinical trial.

Each person's cancer emerges with a private signature of mutations. PACT identifies these cancer mutation targets (neoantigens) for each person, biochemically verifies and captures T cells from their blood and uses its proprietary, non-viral precision genome engineering technologies to manufacture a personalized immune cell therapy product for each person with cancer.

For more information, please visit www.pactpharma.com.

Contacts:

PACT Pharma
Atulya Agarwal
[email protected]

Vida Strategic Partners (on behalf of PACT Pharma)
Tim Brons (Media)
415-675-7402
[email protected]

SOURCE PACT Pharma