Next Generation Autologous TIL Cancer Therapy: Development of GMP manufacturing process

The overall goal of this Phase II SBIR grant proposal is to research and develop the GMP manufacturing process for next-generation tumor infiltrating lymphocyte (TIL) cancer therapeutic for solid tumors. In clinical trials, TIL-based immunotherapies have demonstrated tumor regression and increased survival rates against different cancer types. Despite these encouraging clinical results, durable antitumor responses are typically observed in a subset of patients with advanced cancers like melanoma. This stresses the need to develop more effective TIL-based strategies and to expand efficacy against different cancer types. TIL therapies are hindered in part by low TIL accumulation into tumors, low persistence, weak T cell receptor (TCR) affinity and/or avidity as well as the low expression of tumor antigens on the cell’s surface. Additionally, the presence of suppressive signals on T cells such as Lag3, Tim3, CD39, pose a major obstacle to generating effective and long-lived antitumor T cell responses. In our published and preliminary studies, activating MyD88 signaling in human or mouse T cells, increases antitumor activity and prolongs T cell survival. By fusing the high affinity CD8α (extracellular) to MyD88 (intracellular; CD8α:MyD88) we have developed a novel and universal platform that activates MyD88 signaling strictly upon the engagement of the TCR with the MHC-antigen on tumor cells. CD8α:MyD88 expression in TILs cells substantially increases responses to weak and suboptimal levels of tumor antigens including neoantigens, and in preliminary studies has demonstrated the extraordinary property of reducing the T cells entry into an ‘exhausted state’. Importantly, the use of the CD8α co-receptor represents a ‘universal’ approach to enhancing T cell responses, and can be used in patients regardless of the patient’s HLA type. Through this SBIR Phase II application, we propose the following aims. Aim 1 will research, develop, and manufacture GMP grade g-retroviral vectors. Here, we will generate high virus titer-producing CD8a:MyD88-EGFRt PG-13 cell lines, accompanying analytical assays, and manufacture the GMP CD8a:MyD88-EGFRt g-retroviral vectors. For this aim, we are partnering with a commercial contract development manufacturing organization (CDMO), Vigene Biosciences to generate GMP viral vectors. In Aim 2, we propose to develop and manufacture GMP CD8a:MYD88 engineered TILs (coR8:AMPTM TILs). In collaboration with the Gates Manufacturing Facility (GBF) at the University of Colorado Anschutz Medical Campus (UCAMC) we will conduct process and analytical assay, QC release assay, develop and manufacture of GMP grade coR8:AMPTM TILs. The successful completion of these aims will lead to the pre-IND and IND filings with the FDA for a Phase I clinical trial in patients with immune refractory solid tumors. This activity will be conducted in collaboration with the UCAMC’s Cell Therapy Operations Program (CTOP), Gates Biomanufacturing Facility, and our team members who have extensive experience in cell therapy drug development.