Closed System Automation in a Point-of-Care Approach for CAR T-cell Fabrication

While cancer research has produced many advancements in the modern age, CAR T-cell therapy is one of the most impressive and promising. With the ability to target cancerous cells while leaving those healthy untouched, this new treatment contains the efficacy of even our most aggressive conventional methods while mitigating the collateral damage often caused. Today, one of healthcare's most thriving developing fields, it stands to transform the field of oncology as we know it, saving countless from the devastating effects of cancer and, further still, from the side effects of cancer treatment. Yet, the unfortunate fact is that this breakthrough therapy is inaccessible to all but the most privileged of patients today. If the impact of this revolutionary therapy are ever to be felt, it must be democratized, made accessible, and affordable to all those in need. 

In our series' previous installment, we discussed how centralized manufacturing, the method currently employed in producing autologous CAR T-cell therapies, contributes heavily to issues of accessibility. Involving a central laboratory location staffed with highly trained professionals, this bespoke production method is costly and time-consuming significantly limiting the number of therapies produced per year. To increase production, reduce cost, and improve accessibility, a move must be made to adopt a more efficient method of manufacturing. Namely, a POC (point of care) approach in which therapies are manufactured at the same hospital or cancer treatment facility where they are administered which would do much to improve costs and production output. But how can we bring the manufacturing capabilities of few, centralized advanced laboratories into the confines of a hospital or outpatient clinic? How do we ensure quality and safety on par with that of the centralized lab? 

Fortunately, MIDI is already at work developing an answer to these questions: an all-in-one closed automated system for autologous CAR T-cell fabrication. This system supplants the skills of expensive professional laboratory teams for the reliable capabilities of advanced automation while cutting production times by eliminating the need for transportation and temperature control (i.e. the freeze/ thaw cycle). Meanwhile, it mimics the cleanroom environments maintained in labs by operating in a closed-loop system that makes extensive use of disposable kit to prevent accidental contamination. Implemented correctly, the closed automated system provides scalability, enabling millions of therapies to be produced each year at a fraction of the cost and effort it takes to produce even a single therapy today. 

The Automated Workflow

To understand this automated system further, we should consider how its workflow compares to that of centralized manufacturing. While both processes begin with the same basic procedure, collecting T-Cells from patients, centralized manufacturing requires at multiple instances steps that must be performed to maintain sample integrity and prevent contamination during this manually intensive fabrication process and as materials are transported from treatment facility to production lab and vice versa. The automated workflow, meanwhile, requires none of these tertiary human interactions and processes as biomaterials never actually leave the closed environment of the system until treatment is fully prepared and administered, resulting in a far more streamlined manufacturing process overall. At a high level, the workflow of automated autologous CAR T-Cell fabrication is as follows:

• Leukapheresis: This is the process by which white cells, including T-Cells, are collected from the patient. Usually taking two to three hours, it includes extracting the patient’s whole blood, harvesting white cells from the sample, and reinfusing red cells back into the patient in real time. 

• Isolation of T-Cells: To isolate T-Cells within the sample, it then undergoes a process known as Immunomagnetic Negative Selection. In this process, any unwanted white cells are marked with magnetic particles while T-Cells are left untouched. Tagged cells are then filtered from the sample, typically within as little as ten minutes. 

• Activation: Before genetic engineering can occur, T-Cells must be “activated” or made receptive to receiving foreign genetic materials. This is achieved by stimulating the T-Cells with recombinant antibodies and is usually complete within one day. 

• Genetic Engineering: Referring to the process of introducing foreign DNA or RNA into the T-Cell, this step typically takes one to two days and can be performed via one of two methods:

• Transduction, in which a viral vector is used to introduce foreign DNA into the T-Cell. Once in contact with the T-Cell, the foreign genetic material will instruct it to express CAR (Chimeric Antigen Receptors) on its surface which, when infused into the patient, will attach to proteins on cancerous cells and allow the T-Cell to identify and eliminate them. 
• Or Transfection, a process by which foreign DNA or RNA is introduced into the T-Cell via non-viral methods. There are two major approaches to transfection.
  • Electroporation, in which high-voltage electric pulses are used to open the cell membrane pores of T-Cells, allowing for the introduction of foreign DNA.
  • Ionizable Lipid Nanoparticles, in which ionizable lipids are synthesized into nanoparticles containing mRNA (messenger RNA), which is taken into the cell during regular cellular uptake. 

• Expansion: With T-Cells appropriately modified into CAR T-Cells, they must now be multiplied into a volume large enough to be usable in treatment. To achieve this, T-Cells will be placed into a bioreactor with spinner and, over the course of five to nine days, exposed to a cell culture medium which will support growth. 

• Harvesting, Washing, and Concentrating: Having now reached a much larger volume of up to five liters, the cell culture must now be harvested, washed, and concentrated in preparation for infusion into the patient. While there are several methods for doing so, the most common involves the use of counterflow centrifugal elutriation, a process in which cells are sorted by size and density allowing for removal of dead cells. This step is key to improving cell viability and thus ensuring high quality in the final product. The sample may now be properly considered CAR T-Cell therapy and administered accordingly to the patient, intravenously in a single session. 

Challenges to Implementation

Having this process contained within a single automated system, capable of being operated at any hospital or treatment facility, would do much to increase the number of therapies produced each year. With increased production output, the currently astronomical price per therapy would decrease dramatically, thus allowing more patients than ever to receive treatment. But this transition would not only benefit patients; with improved production and distribution volume, manufacturers would see vastly improved returns on investment providing an incentive for even further development of CAR T-cell therapy. 

Still, even when dealing with the most cutting-edge advancements healthcare has to offer, safety is always of the utmost concern. In developing and implementing point-of-care manufacturing for CAR T-cell therapy, the most significant concern is ensuring that the standard of safety and quality of the product remains uniform with current CAR T-cell therapies produced in a centralized lab. It also includes complying with relevant FDA guidance that may assist in this endeavor. In the case of centralized manufacturing, regulatory guidance includes GMP regulations for CAR T-cell therapy as well as the requirement for any biopharmaceuticals working with human subjects to submit an Investigational New Drug application (IND), which must be approved. 

While products manufactured at point-of-care must follow these guidelines as well, they must also pay attention to more recent publications by the FDA that seek to ensure uniform quality and safety in treatments produced at different care sites. Namely, draft guidance for the manufacture of CAR T-cell products published in March 2022 must be followed, as well as a discussion paper on point-of-care manufacturing published in October of the same year. In these documents, the FDA states that point-of-care manufacturing should clearly demonstrate comparable analytical methods across production sites, and INDs for such products should accurately report on any differences in manufacturing processes that may occur across sites. It is highly recommended that the same standard operating procedures, reagents, and equipment are used across point-of-care sites, as well as that standard materials and practices are set for the calibration of equipment. Considering the sheer number of variables that differ from one hospital or treatment facility to the next, these requirements seem daunting. 

Yet, the closed automated system proposed by MIDI effortlessly ensures uniformity in production methods and environment, even at the most unique point-of-care site. Involving an instrument and disposable set developed under an ISO-13485 quality management system framework, it is the ideal solution to enable widespread point-of-care CAR T-cell therapy manufacturing. 

More effective than chemotherapy while mitigating unfortunate side effects, CAR T-cell therapy represents the next generation of cancer treatment and has the potential to become the bedrock by which the disease can be eradicated altogether at a future point . At MIDI, we are proud to be augmenting this future by developing the tools which allow treatment to reach millions in need. 

To learn more about CAR T-cell therapy and join our fight for democratization, visit the MIDI Innovation Vault™.