MASTER Scaffolds for Rapid, Single-Step Manufacture and Prototyping of CAR-T cells

PROJECT SUMMARY Despite the unprecedented clinical success of chimeric antigen receptor (CAR) T cell therapy, its widespread application is limited by lengthy and labor-intensive ex vivo manufacturing procedures that result in: (i) high cost; (ii) delays to infuse CAR cells to patients with rapidly progressing disease; and (iii) CAR cells with heterogeneous

composition and terminal differentiation, which limit their engraftment and persistence. There is a clear scientific and medical need for approaches to improve CAR T cell production, including methods to reduce cell processing times, reduce manufacturing costs, and reduce CAR cell differentiation. Recently, our labs collaboratively

developed a new technology for CAR cell production called MASTER (Multifunctional Alginate Scaffolds for T cell Engineering and Release). MASTER consists of dry, macroporous alginate materials conjugated to αCD3 and αCD28 antibodies and encapsulating interleukin signaling. CAR generation with MASTER technology

involves seeding freshly isolated, non-activated patient PBMCs together with CAR-encoding retroviral vectors and implanting scaffolds back into patients. Once implanted, MASTER mediates every step of the CAR production process, thereby eliminating the current standard procedural steps of αCD3/αCD28 pre-activation,

viral transduction with spinoculation and interleukin-mediated CAR expansion. In vitro MASTER-generated CAR cells demonstrate reduced cellular differentiation as compared to CAR cells generated with gold-standard, “conventional” clinical protocols. In vivo MASTER-generated CAR cells demonstrate far superior in vivo cell

persistence, enhanced anti-tumor efficacy and far superior prevention of tumor growth after rechallenge. The utility of this system is two-fold: 1) as a transformative therapeutic technology creating enhanced and affordable CAR therapy for cancer care and 2) as a research tool enabling rapid development, prototyping and testing of

CAR therapeutic candidates. We have assembled a focused, multidisciplinary team comprised of an expert in biomaterials and drug delivery (Brudno), an expert in viral engineering and protein production (Birnbaum), two specialists in clinical CAR cell production (Chen, Roy) and a clinician focused on CAR cell therapies (Grover). In

this proposal we seek to further develop and validate MASTER scaffolds and the associated methods to make them ready for widescale utilization by the research and clinical communities, including researchers in related areas eager to work in the CAR field but deterred by the barriers to test CAR construct in vivo. Leveraging

transformative preliminary data that show that the shelf-stable MASTER scaffolds outperform conventional CAR cells in preclinical mouse models of lymphoma, orthotopic pancreatic cancer, and metastatic lung and ovarian tumors this proposal will validate MASTER scaffolds with a wide range of donors and at different scales, with

multiple viral vectors and CAR constructs and delineate the phenotype and function resulting from MASTER production of CAR cells. The successful completion of these aims will propel our ultimate vision of low-cost and tunable generation of CAR cells for both liquid and solid tumors and potentially beyond the oncology space.