Commercial scale manufacture of adult allogeneic cell therapy for regenerative medicine

Commercial growth within the cell therapy industry heavily relies on development of new platform technologies that offer rapid, cost-effective bioprocessing solutions to produce large quantities of high-quality cell product. In this proposal we aim to achieve that by translating a regulator-approved cell immortalization method pioneered by British company ReNeuron (Guildford, Surrey) for treatment of stroke to a new cell type for regenerative cell therapy for other neural disorders. Patients who suffer acute neurologic injury (such as stroke and spinal cord injury) require rapid treatment in order to prevent loss of function. As a single example, in the UK alone 2,000 mostly young people become paralyzed each year due to spinal trauma. Currently there is no cure. Such disability has major consequences for patients, their families, carers and the whole healthcare system. The average cost (direct healthcare and indirect social costs) per patient per year is in the order of £100,000. As a general rule, neural tissue does not regrow after damage. One exception is in the olfactory system where nerve regeneration happens throughout life, enabling us to regain sense of smell following a common cold. Regeneration is possible thanks to a unique cell population called olfactory ensheathing cells (OECs) found in the nose that facilitate new neuronal connections by producing guidance channels. Over the last 20 years Prof. Raisman's group have identified and tested the ability of OECs in combination with co-located fibroblasts to enable neural regeneration. Animal studies have demonstrated safety and efficacy of this cell therapy approach and appropriate ethical approvals for a clinical trial are in place. However, there is a significant hurdle. The present method uses the patient's own (autologous) cells but in acute trauma patients, treatment needs to occur within 14 days. This is not adequate time to take a tissue biopsy, process the cells, characterize and implant a viable therapeutic dose. We will therefore make a step change to universal (allogeneic) OEC cell lines and explore parallel single cell cultures and direct co-culture options. We will use the ReNeuron approach, with advice from their Chief Scientific Officer, Dr. John Sinden, to make universal OEC cell lines that are easily grown in the lab and then reliably silenced upon transplantation into the patient, making it a safe approach. OEC-fibroblast preparations will be produced at different ratios and we will identify key characterization and monitoring issues associated with co-culture. Preparations will be tested for potency and regenerative potential using robust high-throughput in vitro screening assays developed in our lab. GMP-compliant manufacture of a potent cell line will then be initiated. This project will benefit those affected by a range of neurologic injuries. Significantly, the bioprocess industry will gain a pioneering generic platform technology that has been tested in multiple cell types for several indications and gain understanding of manufacturing considerations for co-culturing of cells for therapy. Successful cell based products of the future are likely to comprise two different cell types to produce the therapeutic effect. Therefore it is crucial to derive robust co-culturing methodologies applicable to scalable GMP manufacture. This project will accelerate cures for neurologic injury and expand the UK's bioprocess knowledge pool and skills-base in the area of co-culture to increase the UK's commercial competitive advantage.

The proposal aims to demonstrate the generic potential of a regulator-approved cell immortalization approach pioneered in the UK as a platform technology for scalable expansion of cells for therapy. It will enable 20 years R&D into neuronal regeneration strategies by Prof Raisman's group to be translated into clinical practice. We will address robust scalable expansion and co-culture bioprocessing of olfactory ensheathing cells (OECs) and fibroblasts essential for therapy. Multiple animal studies have demonstrated safety and efficacy of OECs. However, a significant hurdle is that the present method uses autologous cells but treatment needs to occur within 14 days of injury. This is not adequate time to take a biopsy from the patient, process the cells to a therapeutic dose range, characterize and implant into the injury site. For routine therapies available in the limited time window, an off-the-shelf product is essential. We will therefore make a step change to universal (allogeneic) cell lines and explore parallel single cell cultures and direct co-culture options. Using a technique that is already approved by the MHRA we will produce conditional inducible OEC lines. The technology (c-MycER) employed to achieve conditional growth control and genetic stability is a fusion protein comprising a growth promoting gene, c-Myc, and a hormone receptor that is regulated by a synthetic drug, 4-hydroxy-tamoxifen. These modified OECs will proliferate due to activation of c-myc. Cells successfully transduced will be selected and expanded on the basis of resistance to geneticin (only successfully transduced cells will express the geneticin-resistance gene). The resulting OEC lines will then be combined with fibroblasts at various ratios to determine the optimum blend for cell therapy application. The outputs will be tested in vitro, using a rapid, high-throughput screening method established in our lab. We will then proceed to an animal model to determine efficacy and safety.

Creating generic platforms that enable translation of cell research into routine clinical practice requires a multidisciplinary team including scientists, engineers, clinicians and industrialists. There is a highly prescribed regulatory route from discovery through clinical trials before entering the NHS. The project aims to involve researchers and bioprocessors early in the product development cycle to engineer the process to be maximally efficient, robust and appropriately scalable.
Academic impact - Bringing together basic scientists, clinician scientists and biochemical engineers at an early stage in the project will facilitate the production of a scalable method for production of an allogeneic (universal) dual cell therapy. Understanding gained by the engineers from working with scientists will provide knowledge of the engineering challenges that need to be addressed in order to bring dual cell therapies into routine clinical practice. This project will develop methodologies to deliver safe effective OEC-fibroblast combination products that promote regeneration of injured spinal cord. The opportunity for the postdocs and PIs to gain insight and experience of all aspects of the translation process will impact not just on this project but also leave a legacy for the future. In addition, there is the opportunity for academics to gain experience of safely immortalizing cells for therapy using a regulatory approved methodology.
Economic and societal impact - The scalable production of a safe allogeneic dual cell product to successfully restore function to spinal cord injury patients will signify a step change for the healthcare industry and expand the UK's position in the global market for advanced therapies. Translation of lab-based procedures into realistic cell products for manufacture is currently the major bottleneck for treatments that require large numbers of cells. Our approach can overcome this bottleneck and in particular, the dual cell approach and high-throughput screening assays in this project will make an enormous contribution to the 'creation of a vibrant and highly skilled bioprocess community'. The significant advancement that will result from this project will encourage investment in the cell therapy sector and provide a platform technology for the scalable production of dual cell-based therapies to treat other medical indications that require a dual cell therapy intervention. A novel generic platform technology would be of significant value to UK and international industrial stakeholders. If the manufacturing process is robust and well characterized early in a product's development cycle, the chance of a statistically significant true answer in clinical trials will increase since intra- and inter- dose variability will be reduced. This in turn will increase rates of regulatory approval and hence increase investor confidence. Investment will stimulate growth of the sector and encourage support for UK companies that will in turn generate considerable revenue that will contribute to the UK's economic growth and international competitiveness. By producing a safe and cost-effective cell therapy using OECs to regenerate spinal cord neurons, permanent disability in spinal cord injury patients will be prevented. The impact on the patient will be enormous. Their quality of life will be improved and they will not require long-term healthcare provision and will regain mobility and sensory function that is normally permanently lost. If the patient is able to resume employment, the social welfare system will benefit and the UK economy will further gain. Carers, who are often family members who sacrifice their own careers and quality of life to support and care for the patient, will not face such a predicament. Healthcare providers will also have reduced costs, as the need to provide an adequate support structure to the permanently disabled patient will be no longer required.