What does cell therapy manufacturing cost? A framework and methodology to facilitate academic and other small-scale cell therapy manufacturing costings

Considerations for the development of iPSC-derived cell therapies: a review of key challenges by the JSRM-ISCT iPSC Committee

Since their first production in 2007, human induced pluripotent stem cells (iPSCs) have provided a novel platform for the development of various cell therapies targeting a spectrum of diseases, ranging from rare genetic eye disorders to cancer treatment. However, several challenges must be tackled for iPSC-based cell therapy to enter the market and achieve broader global adoption. This white paper, authored by the Japanese Society for Regenerative Medicine (JSRM) - International Society for Cell Therapy (ISCT) iPSC Committee delves into the hurdles encountered in the pursuit of safe and economically viable iPSC-based therapies, particularly from the standpoint of the cell therapy industry. It discusses differences in global guidelines and regulatory frameworks, outlines a series of quality control tests required to ensure the safety of the cell therapy, and provides details and important considerations around cost of goods (COGs), including the impact of automated advanced manufacturing.

A roadmap for affordable genetic medicines

Twenty genetic therapies have been approved by the US Food and Drug Administration to date, a number that now includes the first CRISPR genome-editing therapy for sickle cell disease-CASGEVY (exagamglogene autotemcel, Vertex Pharmaceuticals). This extraordinary milestone is widely celebrated owing to the promise for future genome-editing treatments of previously intractable genetic disorders and cancers. At the same time, such genetic therapies are the most expensive drugs on the market, with list prices exceeding US$4 million per patient. Although all approved cell and gene therapies trace their origins to academic or government research institutions, reliance on for-profit pharmaceutical companies for subsequent development and commercialization results in prices that prioritize recouping investments, paying for candidate product failures and meeting investor and shareholder expectations. To increase affordability and access, sustainable discovery-to-market alternatives are needed that address system-wide deficiencies. Here we present recommendations of a multidisciplinary task force assembled to chart such a path. We describe a pricing structure that, once implemented, could reduce per-patient cost tenfold and propose a business model that distributes responsibilities while leveraging diverse funding sources. We also outline how academic licensing provisions, manufacturing innovation and supportive regulations can reduce cost and enable broader patient treatment.

Interfacing data science with cell therapy manufacturing: where we are and where we need to be

Although several cell-based therapies have received FDA approval, and others are showing promising results, scalable, and quality-driven reproducible manufacturing of therapeutic cells at a lower cost remains challenging. Challenges include starting material and patient variability, limited understanding of manufacturing process parameter effects on quality, complex supply chain logistics, and lack of predictive, well-understood product quality attributes. These issues can manifest as increased production costs, longer production times, greater batch-to-batch variability, and lower overall yield of viable, high-quality cells. The lack of data-driven insights and decision-making in cell manufacturing and delivery is an underlying commonality behind all these problems. Data collection and analytics from discovery, preclinical and clinical research, process development, and product manufacturing have not been sufficiently utilized to develop a "systems" understanding and identify actionable controls. Experience from other industries shows that data science and analytics can drive technological innovations and manufacturing optimization, leading to improved consistency, reduced risk, and lower cost. The cell therapy manufacturing industry will benefit from implementing data science tools, such as data-driven modeling, data management and mining, AI, and machine learning. The integration of data-driven predictive capabilities into cell therapy manufacturing, such as predicting product quality and clinical outcomes based on manufacturing data, or ensuring robustness and reliability using data-driven supply-chain modeling could enable more precise and efficient production processes and lead to better patient access and outcomes. In this review, we introduce some of the relevant computational and data science tools and how they are being or can be implemented in the cell therapy manufacturing workflow. We also identify areas where innovative approaches are required to address challenges and opportunities specific to the cell therapy industry. We conclude that interfacing data science throughout a cell therapy product lifecycle, developing data-driven manufacturing workflow, designing better data collection tools and algorithms, using data analytics and AI-based methods to better understand critical quality attributes and critical-process parameters, and training the appropriate workforce will be critical for overcoming current industry and regulatory barriers and accelerating clinical translation.

Advances in manufacturing chimeric antigen receptor immune cell therapies

Biomedical research has witnessed significant strides in manufacturing chimeric antigen receptor T cell (CAR-T) therapies, marking a transformative era in cellular immunotherapy. Nevertheless, existing manufacturing methods for autologous cell therapies still pose several challenges related to cost, immune cell source, safety risks, and scalability. These challenges have motivated recent efforts to optimize process development and manufacturing for cell therapies using automated closed-system bioreactors and models created using artificial intelligence. Simultaneously, non-viral gene transfer methods like mRNA, CRISPR genome editing, and transposons are being applied to engineer T cells and other immune cells like macrophages and natural killer cells. Alternative sources of primary immune cells and stem cells are being developed to generate universal, allogeneic therapies, signaling a shift away from the current autologous paradigm. These multifaceted innovations in manufacturing underscore a collective effort to propel this therapeutic approach toward broader clinical adoption and improved patient outcomes in the evolving landscape of cancer treatment. Here, we review current CAR immune cell manufacturing strategies and highlight recent advancements in cell therapy scale-up, automation, process development, and engineering.

Synthetic biology approaches for enhancing safety and specificity of CAR-T cell therapies for solid cancers

CAR-T cell therapies have been successful in treating numerous hematologic malignancies as the T cell can be engineered to target a specific antigen associated with the disease. However, translating CAR-T cell therapies for solid cancers is proving more challenging due to the lack of truly tumor-associated antigens and the high risk of off-target toxicities. To combat this, numerous synthetic biology mechanisms are being incorporated to create safer and more specific CAR-T cells that can be spatiotemporally controlled with increased precision. Here, we seek to summarize and analyze the advancements for CAR-T cell therapies with respect to clinical implementation, from the perspective of synthetic biology and immunology. This review should serve as a resource for further investigation and growth within the field of personalized cellular therapies.

EBV T-cell immunotherapy generated by peptide selection has enhanced effector functionality compared to LCL stimulation

Adoptive immunotherapy with Epstein-Barr virus (EBV)-specific T cells is an effective treatment for relapsed or refractory EBV-induced post-transplant lymphoproliferative disorders (PTLD) with overall survival rates of up to 69%. EBV-specific T cells have been conventionally made by repeated stimulation with EBV-transformed lymphoblastoid cell lines (LCL), which act as antigen-presenting cells. However, this process is expensive, takes many months, and has practical risks associated with live virus. We have developed a peptide-based, virus-free, serum-free closed system to manufacture a bank of virus-specific T cells (VST) for clinical use. We compared these with standard LCL-derived VST using comprehensive characterization and potency assays to determine differences that might influence clinical benefits. Multi-parameter flow cytometry revealed that peptide-derived VST had an expanded central memory population and less exhaustion marker expression than LCL-derived VST. A quantitative HLA-matched allogeneic cytotoxicity assay demonstrated similar specific killing of EBV-infected targets, though peptide-derived EBV T cells had a significantly higher expression of antiviral cytokines and degranulation markers after antigen recall. High-throughput T cell receptor-beta (TCRβ) sequencing demonstrated oligoclonal repertoires, with more matches to known EBV-binding complementary determining region 3 (CDR3) sequences in peptide-derived EBV T cells. Peptide-derived products showed broader and enhanced specificities to EBV nuclear antigens (EBNAs) in both CD8 and CD4 compartments, which may improve the targeting of highly expressed latency antigens in PTLD. Importantly, peptide-based isolation and expansion allows rapid manufacture and significantly increased product yield over conventional LCL-based approaches.

Translating mesenchymal stem cell and their exosome research into GMP compliant advanced therapy products: Promises, problems and prospects

Mesenchymal stem cells (MSCs) are one of the few stem cell types used in clinical practice as therapeutic agents for immunomodulation and ischemic tissue repair, due to their unique paracrine capacity, multiple differentiation potential, active components in exosomes, and effective mitochondria donation. At present, MSCs derived from tissues such as bone marrow and umbilical cord are widely applied in preclinical and clinical studies. Nevertheless, there remain challenges to the maintenance of consistently good quality MSCs derived from different donors or tissues, directly impacting their application as advanced therapy products. In this review, we discuss the promises, problems, and prospects associated with translation of MSC research into a pharmaceutical product. We review the hurdles encountered in translation of MSCs and MSC-exosomes from the research bench to an advanced therapy product compliant with good manufacturing practice (GMP). These difficulties include how to set up GMP-compliant protocols, what factors affect raw material selection, cell expansion to product formulation, establishment of quality control (QC) parameters, and quality assurance to comply with GMP standards. To avoid human error and reduce the risk of contamination, an automatic, closed system that allows real-time monitoring of QC should be considered. We also highlight potential advantages of pluripotent stem cells as an alternative source for MSC and exosomes generation and manufacture.

Cost-effectiveness of treating advanced melanoma with tumor-infiltrating lymphocytes based on an international randomized phase 3 clinical trial

INTRODUCTION

In a multicenter, open-label randomized phase 3 clinical trial conducted in the Netherlands and Denmark, treatment with ex vivo-expanded tumor-infiltrating lymphocytes (TIL-NKI/CCIT) from autologous melanoma tumor compared with ipilimumab improved progression-free survival in patients with unresectable stage IIIC-IV melanoma after failure of first-line or second-line treatment. Based on this trial, we conducted a cost-utility analysis.

METHODS

A Markov decision model was constructed to estimate expected costs (expressed in 2021€) and outcomes (quality-adjusted life years (QALYs)) of TIL-NKI/CCIT versus ipilimumab in the Netherlands. The Danish setting was assessed in a scenario analysis. A modified societal perspective was applied over a lifetime horizon. TIL-NKI/CCIT production costs were estimated via activity-based costing. Through sensitivity analyses, uncertainties and their impact on the incremental cost-effectiveness ratio (ICER) were assessed.

RESULTS

Mean total undiscounted lifetime benefits were 4.47 life years (LYs) and 3.52 QALYs for TIL-NKI/CCIT and 3.33 LYs and 2.46 QALYs for ipilimumab. Total lifetime undiscounted costs in the Netherlands were €347,168 for TIL-NKI/CCIT (including €67,547 for production costs) compared with €433,634 for ipilimumab. Undiscounted lifetime cost in the Danish scenario were €337,309 and €436,135, respectively. This resulted in a dominant situation for TIL-NKI/CCIT compared with ipilimumab in both countries, meaning incremental QALYs were gained at lower costs. Survival probabilities, and utility in progressive disease affected the ICER most.

CONCLUSION

Based on the data of a randomized phase 3 trial, treatment with TIL-NKI/CCIT in patients with unresectable stage IIIC-IV melanoma is cost-effective and cost-saving, both in the current Dutch and Danish setting. These findings led to inclusion of TIL-NKI/CCIT as insured care and treatment guidelines. Publicly funded development of the TIL-NKI/CCIT cell therapy shows realistic promise to further explore development of effective personalized treatment while warranting economic sustainability of healthcare systems.

Operator-derived particles and falling bacteria in biosafety cabinets

Introduction

To ensure the sterility of cell products that cannot undergo conventional sterilization processes, it is imperative to establish and maintain a clean room environment, regulated through environmental monitoring, including particle counts. Nevertheless, the impact of particles generated by operators as potential contaminants remains uncertain. Thus, in this study, we conducted an accelerated test to assess the correlation between particles generated by operators and airborne bacteria, utilizing biosafety cabinets within a typical laboratory setting. These biosafety cabinets create a controlled environment with air conditioning and high-efficiency particulate air (HEPA) filters, offering fundamental data relevant to cell production.

Materials and methods

We conducted a simulation followed by real-time experiments involving human operations to explore the quantity of particles, particle sizes, and the percentage of bacteria within these particles. This investigation focused on conditions with heightened particle generation from operators within a biosafety cabinet. The experiment was conducted on operators wearing textile and non-woven dustless clothing within biosafety cabinets. It entailed tapping the upper arms for a duration of 2 min.

Results

Observations under biosafety cabinet-off conditions revealed the presence of various particles and falling bacteria in textile clothing. In contrast, no particles or falling bacteria were detected in operators wearing dustless clothing within biosafety cabinets. Notably, a correlation between 5 μm particles and colony-forming units in textile clothing was identified through this analysis. The ratio of falling bacteria to the total number of particles within the biosafety cabinet was 0.8 ± 0.5 % for textile clothing, while it was significantly lower at 0.04 ± 0.2 % for dustless clothing.

Conclusion

This study demonstrated that the number of particles and falling bacteria varied depending on the type of clothing and that quantitative data could be used to identify risks and provide basic data for operator education and evidence-based control methods in aseptic manufacturing areas. Although, this study aims to serve as an accelerated test operating under worst-case conditions, the results need to make sure the study range in general research.

Macromolecular Crowding Enhances Matrix Protein Deposition in Tissue-Engineered Vascular Grafts

Successful in vitro culture of small-diameter tissue-engineered vascular grafts (TEVGs) requires rapid deposition of biomacromolecules secreted by vascular smooth muscle cells in a polyglycolic acid mesh scaffold's three-dimensional (3D) porous environment. However, common media have lower crowding conditions than in vivo tissue fluids. In addition, during the early stages of construction, most of the biomolecules secreted by the cells into the medium are lost, which negatively affects the TEVG culture process. In this study, we propose the use of macromolecular crowding (MMC) to enhance medium crowding to improve the deposition and self-assembly efficiency of major biomolecules in the early stages of TEVG culture. The addition of carrageenan significantly increased the degree of MMC in the culture medium without affecting cell viability, proliferation, and metabolic activity. Protein analysis demonstrated that the deposition of collagen types I and III and fibronectin increased significantly in the cell layers of two-dimensional and 3D smooth muscle cell cultures after the addition of a MMC agent. Collagen type I in the culture medium decreased significantly compared with that in the medium without a MMC agent. Scanning electron microscopy demonstrated that MMC agents considerably enhanced the formation of matrix protein structures during the early stages of 3D culture. Hence, MMC modifies the crowding degree of the culture medium, resulting in the rapid formation of numerous matrix proteins and fiber structures. Impact Statement Small-diameter tissue-engineered vascular grafts (TEVGs) are one of the most promising means of treating cardiovascular diseases; however, the in vitro construction of TEVGs has some limitations, such as slow deposition of extracellular matrix (ECM), long culture period, and poor mechanical properties. We hypothesized that macromolecular crowding can increase the crowding of the culture medium to construct a more bionic microenvironment, which enhances ECM deposition in the medium to the cell layer and reduces collagen loss, accelerating and enhancing TEVG culture and construction in vitro.

Post-marketing authorisation safety and efficacy surveillance of advanced therapy medicinal products in Brazil, the European Union, the United States and Japan

BACKGROUND AIMS

Advanced therapy medicinal products (ATMPs) are a class of biological products for human use that are based on gene, tissues or cells. ATMPs have peculiar characteristics when compared with traditional medicines. In this regard, long-term safety and efficacy follow-up systems of individuals treated with ATMPs have become necessary and may present unique challenges, because unlike conventional drugs and biologics, these products can exert their effects for years after administration. This work seeks to assess the requirements foreseen in the regulatory frameworks for the post-marketing authorization safety and efficacy surveillance for ATMPs in Brazil, European Union (EU), Japan and United States, which are some of the members of the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use.

METHODS

We reviewed the scientific literature and official documents of regulatory agencies (RAs) in Brazil, the EU, Japan and the United States.

RESULTS AND CONCLUSIONS

RAs in the EU, US and Japan have developed regulatory guidelines for the post-marketing surveillance of ATMPs. These guidelines aim at implementing surveillance plans for monitoring adverse events, including late ones, after marketing authorization. All the ATMPs authorized by the RAs studied, submitted some type of post-marketing requirement to supplement safety and efficacy data, according to the regulations and terminology used by those jurisdictions.

Manufacturing and validation of Good Manufacturing Practice-compliant regulatory dendritic cells for infusion into organ transplant recipients

BACKGROUND AIMS

Regulatory (or "tolerogenic") dendritic cells (DCregs) are a highly promising, innovative cell therapy for the induction or restoration of antigen-specific tolerance in immune-mediated inflammatory disorders. These conditions include organ allograft rejection, graft-versus-host disease following bone marrow transplantation and various autoimmune disorders. DCregs generated for adoptive transfer have potential to reduce patients' dependence on non-specific immunosuppressive drugs that can induce serious side effects and enhance the risk of infection and certain types of cancer. Here, our aim was to provide a detailed account of our experience manufacturing and validating comparatively large numbers of Good Manufacturing Practice-grade DCregs for systemic (intravenous) infusion into 28 organ (liver) transplant recipients and to discuss factors that influence the satisfaction of release criteria and attainment of target cell numbers.

RESULTS

DCregs were generated in granulocyte-macrophage colony stimulating factor and interleukin (IL)-4 from elutriated monocyte fractions isolated from non-mobilized leukapheresis products of consenting healthy adult prospective liver transplant donors. Vitamin D3 was added on day 0 and 4 and IL-10 on day 4 during the 7-day culture period. Release and post-release criteria included cell viability, purity, phenotype, sterility and functional assessment. The overall conversion rate of monocytes to DCregs was 28 ± 8.2%, with 94 ± 5.1% product viability. The mean cell surface T-cell co-inhibitory to co-stimulatory molecule (programmed death ligand-1:CD86) mean fluorescence intensity ratio was 3.9 ± 2.2, and the mean ratio of anti-inflammatory:pro-inflammatory cytokine product (IL-10:IL-12p70) secreted upon CD40 ligation was 60 ± 63 (median = 40). The mean total number of DCregs generated from a single leukapheresis product (n = 25 donors) and from two leukapheresis products (n = 3 donors) was 489 ± 223 × 10⁶ (n = 28). The mean total number of DCregs infused was 5.9 ± 2.8 × 10⁶ per kg body weight. DCreg numbers within a target cell range of 2.5-10 × 10⁶/kg were achieved for 25 of 27 (92.6%) of products generated.

CONCLUSIONS

High-purity DCregs meeting a range of quality criteria were readily generated from circulating blood monocytes under Good Manufacturing Practice conditions to meet target cell numbers for infusion into prospective organ transplant recipients.

Automated Good Manufacturing Practice-Compatible CRISPR-Cas9 Editing of Hematopoietic Stem and Progenitor Cells for Clinical Treatment of β-Hemoglobinopathies

Cellular therapies hold enormous potential for the cure of severe hematological and oncological disorders. The forefront of innovative gene therapy approaches including therapeutic gene editing and hematopoietic stem cell transplantation needs to be processed by good manufacturing practice to ensure safe application in patients. In the present study, an effective transfection protocol for automated clinical-scale production of genetically modified hematopoietic stem and progenitor cells (HSPCs) using the CliniMACS Prodigy^® system including the CliniMACS Electroporator (Miltenyi Biotec) was established. As a proof-of-concept, the enhancer of the BCL11A gene, clustered regularly interspaced short palindromic repeat (CRISPR) target in ongoing clinical trials for β-thalassemia and sickle-cell disease treatment, was disrupted by the CRISPR-Cas9 system simulating a large-scale clinical scenario, yielding 100 million HSPCs with high editing efficiency. In vitro erythroid differentiation and high-performance liquid chromatography analyses corroborated fetal hemoglobin resurgence in edited samples, supporting the feasibility of running the complete process of HSPC gene editing in an automated closed system.

Challenges for Economic Evaluations of Advanced Therapy Medicinal Products: A Systematic Review

OBJECTIVES

Advanced therapy medicinal products (ATMPs) are drugs for human use for the treatment of chronic, degenerative, or life-threatening diseases that are based on genes, tissues, or cells. This article aimed to identify and critically review published economic analyses of ATMPs.

METHODS

A systematic review of economic analyses of ATMPs was undertaken. Study characteristics, design, sources of data, resources and unit costs, modeling and extrapolation methods, study results, and sensitivity analyses were assessed.

RESULTS

A total of 46 economic analyses of ATMP (from 45 articles) were included; 4 were cell therapy medicinal products, 33 gene therapy medicinal products, and 9 tissue-engineered products. 30 therapies had commercial marketing approval; 39 studies were cost-utility analysis, 5 were cost-effectiveness analysis, and 2 were cost only studies. Four studies predicted that the ATMP offered a step change in the management of the condition and 10 studies estimated that the ATMP would offer a lower mean cost.

CONCLUSIONS

Comparison with historical controls, pooling of data, and use of techniques such as mixture cure fraction models should be used cautiously. Sensitivity analyses should be used across a plausible range of prices. Clinical studies need to be designed to align with health technology assessment requirements, including generic quality of life, and payers should aim for clarity of criteria. Regulators and national payers should aim for compatibility of registers to allow interchange of data. Given the increasing reliance on industry-funded economic analyses, careful critical review is recommended.

Hypothermic Preservation of Adipose-Derived Mesenchymal Stromal Cells as a Viable Solution for the Storage and Distribution of Cell Therapy Products

Cell and gene therapies (CGT) have reached new therapeutic targets but have noticeably high prices. Solutions to reduce production costs might be found in CGT storage and transportation since they typically involve cryopreservation, which is a heavily burdened process. Encapsulation at hypothermic temperatures (e.g., 2-8 °C) could be a feasible alternative. Adipose tissue-derived mesenchymal stromal cells (MSC(AT)) expanded using fetal bovine serum (FBS)- (MSC-FBS) or human platelet lysate (HPL)-supplemented mediums (MSC-HPL) were encapsulated in alginate beads for 30 min, 5 days, and 12 days. After bead release, cell recovery and viability were determined to assess encapsulation performance. MSC identity was verified by flow cytometry, and a set of assays was performed to evaluate functionality. MSC(AT) were able to survive encapsulated for a standard transportation period of 5 days, with recovery values of 56 ± 5% for MSC-FBS and 77 ± 6% for MSC-HPL (which is a negligible drop compared to earlier timepoints). Importantly, MSC function did not suffer from encapsulation, with recovered cells showing robust differentiation potential, expression of immunomodulatory molecules, and hematopoietic support capacity. MSC(AT) encapsulation was proven possible for a remarkable 12 day period. There is currently no solution to completely replace cryopreservation in CGT logistics and supply chain, although encapsulation has shown potential to act as a serious competitor.

Towards sustainability and affordability of expensive cell and gene therapies? Applying a cost-based pricing model to estimate prices for Libmeldy and Zolgensma

BACKGROUND AIMS

Drug prices are regarded as one of the most influential factors in determining accessibility and affordability to novel therapies. Cell and gene therapies such as OTL-200 (brand name: Libmeldy) and AVXS-101 (brand name: Zolgensma) with (expected) list prices of 3.0 million EUR and 1.9 million EUR per treatment, respectively, spark a global debate on the affordability of such therapies. The aim of this study was to use a recently published cost-based pricing model to calculate prices for cell and gene therapies, with OTL-200 and AVXS-101 as case study examples.

METHODS

Using the pricing model proposed by Uyl-de Groot and Löwenberg, we estimated a price for both therapies. We searched the literature and online public sources to estimate (i) research and development (R&D) expenses adjusted for risk of failure and cost of capital, (ii) the eligible patient population and (iii) costs of drug manufacturing to calculate a base-case price for OTL-200 and AVXS-101. All model input parameters were varied in a stepwise, deterministic sensitivity analysis and scenario analyses to assess their impact on the calculated prices.

RESULTS

Prices for OTL-200 and AVXS-101 were estimated at 1 048 138 EUR and 380 444 EUR per treatment, respectively. In deterministic sensitivity analyses, varying R&D estimates had the greatest impact on the price for OTL-200, whereas for AVXS-101, changes in the profit margin changed the calculated price substantially. Highest prices in scenario analyses were achieved when assuming the lowest number of patients for OTL-200 and highest R&D expenses for AVXS-101. The lowest R&D expenses scenario resulted in lowest prices for either therapy.

CONCLUSIONS

Our results show that, using the proposed model, prices for both OTL-200 and AVXS-101 lie substantially below the currently (proposed) list prices for both therapies. Nevertheless, the uncertainty of the used model input parameters is considerable, which translates in a wide range of estimated prices. This is mainly because of a lack of transparency from pharmaceutical companies regarding R&D expenses and the costs of drug manufacturing. Simultaneously, the disease indications for both therapies remain heavily understudied in terms of their epidemiological profile. Despite the considerable variation in the estimated prices, our results may support the public debate on value-based and cost-based pricing models, and on "fair" drug prices in general.

Joint Tissue Protective and Immune-Modulating miRNA Landscape of Mesenchymal Stromal Cell-Derived Extracellular Vesicles under Different Osteoarthritis-Mimicking Conditions

In regenerative medicine related to orthopedic conditions, mesenchymal stromal cells (MSCs) and their extracellular vesicles (EVs) have been proposed as innovative clinical options. The definition of EV-shuttled signals and their modulation under orthopedic settings, such as osteoarthritis (OA), is crucial for MSC-related research, both for basic science and for use in clinical settings, either as therapeutics or as producers of cell-free products such as EVs or secretome. The objective of this work is to compare the literature available on high-throughput EV-miRNA data obtained from adipose-derived MSCs (ASCs) in standard conditions or cultured in high levels of IFNγ, low-level inflammatory conditions mimicking OA synovial fluid (SF), and OA-SF. The first result was that both IFNγ and low-level inflammatory treatment led to an increase, whereas SF led to a reduction in EV release. Second, more than 200 EV-miRNAs were found to be shared across the different conditions. After a bioinformatics search through experimentally validated and OA-related targets, pathways and tissues, several miRNAs resulted in the restoration of cartilage and synovium stability and the homeostasis of inflammatory cells, including macrophages, promoting their switch towards an M2 anti-inflammatory phenotype. Third, IFNγ and especially SF culturing were able to modulate the overall EV-miRNA fingerprint, although the main molecular messages related to OA resulted conserved between treatments with the majority of modulations within 2-fold range. In conclusion, ASC EV-miRNAs may be modulated in their overall landscape by OA-related culturing conditions albeit resulted largely stable in their specific OA-protective signals allowing for a faster clinical translation of these new cell-free therapies for joint diseases.

Design of experiments as a decision tool for cell therapy manufacturing

BACKGROUND AIMS

Cell therapies are costlier to manufacture than small molecules and protein therapeutics because they require multiple manipulations and are often produced in an autologous manner. Strategies to lower the cost of goods to produce a cell therapy could make a significant impact on its total cost.

METHODS

Borrowing from the field of bioprocess development, the authors took a design of experiments (DoE)-based approach to understanding the manufacture of a cell therapy product in pre-clinical development, analyzing main cost factors in the production process. The cells used for these studies were autologous CD4+ T lymphocytes gene-edited using CRISPR/Cas9 and recombinant adeno-associated virus (AAV) to restore normal FOXP3 gene expression as a prospective investigational product for patients with immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome.

RESULTS

Using gene editing efficiency as the response variable, an initial screen was conducted for other variables that could influence the editing frequency. The multiplicity of infection (MOI) of AAV and amount of single guide RNA (sgRNA) were the significant factors used for the optimization step to generate a response contour plot. Cost analysis was done for multiple points in the design space to find cost drivers that could be reduced. For the range of values tested (50 000-750 000 vg/cell AAV and 0.8-4 μg sgRNA), editing with the highest MOI and sgRNA yielded the best gene editing frequency. However, cost analysis showed the optimal solution was gene editing at 193 000 vg/cell AAV and 1.78 μg sgRNA.

CONCLUSIONS

The authors used DoE to define key factors affecting the gene editing process for a potential investigational therapeutic, providing a novel and faster data-based approach to understanding factors driving complex biological processes. This approach could be applied in process development and aid in achieving more robust strategies for the manufacture of cellular therapeutics.

New paradigms in regenerative engineering: Emerging role of extracellular vesicles paired with instructive biomaterials

Mesenchymal stem cells (MSCs) have long been regarded as critical components of regenerative medicine strategies, given their multipotency and persistence in a variety of tissues. Recently, the specific role of MSCs in mediating regenerative outcomes has been attributed (in part) to secreted factors from transplanted cells, namely extracellular vesicles. This viewpoint manuscript highlights the promise of cell-derived extracellular vesicles as agents of regeneration, enhanced by synergy with appropriate biomaterials platforms. Extracellular vesicles are a potentially interesting regenerative tool to enhance the synergy between MSCs and biomaterials. As a result, we believe these technologies will improve patient outcomes through efficient therapeutic strategies resulting in predictable patient outcomes.

Efficient recovery of potent tumour-infiltrating lymphocytes through quantitative immunomagnetic cell sorting

Adoptive cell therapies require the recovery and expansion of highly potent tumour-infiltrating lymphocytes (TILs). However, TILs in tumours are rare and difficult to isolate efficiently, which hinders the optimization of therapeutic potency and dose. Here we show that a configurable microfluidic device can efficiently recover potent TILs from solid tumours by leveraging specific expression levels of target cell-surface markers. The device, which is sandwiched by permanent magnets, balances magnetic forces and fluidic drag forces to sort cells labelled with magnetic nanoparticles conjugated with antibodies for the target markers. Compared with conventional cell sorting, immunomagnetic cell sorting recovered up to 30-fold higher numbers of TILs, and the higher levels and diversity of the recovered TILs accelerated TIL expansion and enhanced their therapeutic potency. Immunomagnetic cell sorting also allowed us to identify and isolate potent TIL subpopulations, in particular TILs with moderate levels of CD39 (a marker of T-cell reactivity to tumours and T-cell exhaustion), which we found are tumour-specific, self-renewable and essential for the long-term success of adoptive cell therapies.

Challenges in the market access of regenerative medicines, and implications for manufacturers and decision-makers: a systematic review

Aim: Regenerative medicines (RMs) are expected to transform the treatment paradigm of rare, life-threatening diseases, while substantial challenges impede its market access. This study aimed to present these challenges. Materials & methods: Publications identified in the Medline and Embase databases until December 2020 were included. Results: Uncertainties around the relative effectiveness and long-term benefits of RMs are most scrutinized. A new reference case for RMs is questionable, but examining impacts of study perspective, time horizon, discount rate and extrapolation methods on estimates is advised. Establishing reasonable prices of RMs requires increased transparency in the development costs and better values measurements. Outcome-based payments require considerable investments and potential legislative adjustments. Conclusion: Greater flexibility for health technology assessment and economic analyses of RMs is necessary. This comprehensive review may prompt more multi-stakeholder conversations to discuss the optimized strategy for value assessment, pricing and payment in order to accelerate the market access of RMs.

Mechanical Stimulation after Centrifuge-Free Nano-Electroporative Transfection Is Efficient and Maintains Long-Term T Cell Functionalities

Transfection is an essential step in genetic engineering and cell therapies. While a number of non-viral micro- and nano-technologies have been developed to deliver DNA plasmids into the cell cytoplasm, one of the most challenging and least efficient steps is DNA transport to and expression in the nucleus. Here, the magnetic nano-electro-injection (MagNEI) platform is described which makes use of oscillatory mechanical stimulation after cytoplasmic delivery with high aspect-ratio nano-structures to achieve stable (>2 weeks) net transfection efficiency (efficiency × viability) of 50% in primary human T cells. This is, to the best of the authors' knowledge, the highest net efficiency reported for primary T cells using a centrifuge-free, non-viral transfection method, in the absence of cell selection, and with a clinically relevant cargo size (>12 kbp). Wireless mechanical stimulation downregulates the expression of microtubule motor protein gene, KIF2A, which increases local DNA concentration near the nuclei, resulting in enhanced DNA transfection. Magnetic forces also accelerate membrane repair by promoting actin cytoskeletal remodeling which preserves key biological attributes including cell proliferation and gene expressions. These results demonstrate MagNEI as a powerful non-viral transfection technique for progress toward fully closed, end-to-end T cell manufacturing with less human labor, lower production cost, and shorter delay.

Transforming eukaryotic cell culture with macromolecular crowding

In multicellular organisms, the intracellular and extracellular spaces are considerably packed with a diverse range of macromolecular species. Yet, standard eukaryotic cell culture is performed in dilute, and deprived of macromolecules culture media, that barely imitate the density and complex macromolecular composition of tissues. Essentially, we drown cells in a sea of media and then expect them to perform physiologically. Herein, we argue the use of macromolecular crowding (MMC) in eukaryotic cell culture for regenerative medicine and drug discovery purposes.

Synergistic Effect of Biomaterial and Stem Cell for Skin Tissue Engineering in Cutaneous Wound Healing: A Concise Review

Skin tissue engineering has made remarkable progress in wound healing treatment with the advent of newer fabrication strategies using natural/synthetic polymers and stem cells. Stem cell therapy is used to treat a wide range of injuries and degenerative diseases of the skin. Nevertheless, many related studies demonstrated modest improvement in organ functions due to the low survival rate of transplanted cells at the targeted injured area. Thus, incorporating stem cells into biomaterial offer niches to transplanted stem cells, enhancing their delivery and therapeutic effects. Currently, through the skin tissue engineering approach, many attempts have employed biomaterials as a platform to improve the engraftment of implanted cells and facilitate the function of exogenous cells by mimicking the tissue microenvironment. This review aims to identify the limitations of stem cell therapy in wound healing treatment and potentially highlight how the use of various biomaterials can enhance the therapeutic efficiency of stem cells in tissue regeneration post-implantation. Moreover, the review discusses the combined effects of stem cells and biomaterials in in vitro and in vivo settings followed by identifying the key factors contributing to the treatment outcomes. Apart from stem cells and biomaterials, the role of growth factors and other cellular substitutes used in effective wound healing treatment has been mentioned. In conclusion, the synergistic effect of biomaterials and stem cells provided significant effectiveness in therapeutic outcomes mainly in wound healing improvement.

Hyaluronic Acid as Macromolecular Crowder in Equine Adipose-Derived Stem Cell Cultures

The use of macromolecular crowding in the development of extracellular matrix-rich cell-assembled tissue equivalents is continuously gaining pace in regenerative engineering. Despite the significant advancements in the field, the optimal macromolecular crowder still remains elusive. Herein, the physicochemical properties of different concentrations of different molecular weights hyaluronic acid (HA) and their influence on equine adipose-derived stem cell cultures were assessed. Within the different concentrations and molecular weight HAs, the 10 mg/mL 100 kDa and 500 kDa HAs exhibited the highest negative charge and hydrodynamic radius, and the 10 mg/mL 100 kDa HA exhibited the lowest polydispersity index and the highest % fraction volume occupancy. Although HA had the potential to act as a macromolecular crowding agent, it did not outperform carrageenan and Ficoll®, the most widely used macromolecular crowding molecules, in enhanced and accelerated collagen I, collagen III and collagen IV deposition.

Scaffold-free cell-based tissue engineering therapies: advances, shortfalls and forecast

Cell-based scaffold-free therapies seek to develop in vitro organotypic three-dimensional (3D) tissue-like surrogates, capitalising upon the inherent capacity of cells to create tissues with efficiency and sophistication that is still unparalleled by human-made devices. Although automation systems have been realised and (some) success stories have been witnessed over the years in clinical and commercial arenas, in vitro organogenesis is far from becoming a standard way of care. This limited technology transfer is largely attributed to scalability-associated costs, considering that the development of a borderline 3D implantable device requires very high number of functional cells and prolonged ex vivo culture periods. Herein, we critically discuss advancements and shortfalls of scaffold-free cell-based tissue engineering strategies, along with pioneering concepts that have the potential to transform regenerative and reparative medicine.

Evaluation of the effectiveness of a new cryopreservation system based on a two-compartment vial for the cryopreservation of cell therapy products

BACKGROUND AIMS

Successful cell cryopreservation and banking remain a major challenge for the manufacture of cell therapy products, particularly in relation to providing a hermetic, sterile cryovial that ensures optimal viability and stability post-thaw while minimizing exposure to toxic cryoprotective agents, typically dimethyl sulfoxide (Me₂SO).

METHODS

In the present study, the authors evaluated the effectiveness and functionality of Limbo technology (Cellulis S.L., Santoña, Spain). This system provides a hermetic vial with two compartments (one for adding cells with the cryoprotective agent solution and the other for the diluent solution) and an automated defrosting device. Limbo technology (Cellulis S.L.) allows reduction of the final amount of Me₂SO, sidestepping washing and dilution steps and favoring standardization. The study was performed in several Good Manufacturing Practice laboratories manufacturing diverse cell therapy products (human mesenchymal stromal cells, hematopoietic progenitor cells, leukapheresis products, fibroblasts and induced pluripotent stem cells). Laboratories compared Limbo technology (Cellulis S.L.) with their standard cryopreservation procedure, analyzing cell recovery, viability, phenotype and functionality.

RESULTS

Limbo technology (Cellulis S.L.) maintained the viability and functionality of most of the cell products and preserved sterility while reducing the final concentration of Me₂SO.

CONCLUSIONS

Results showed that use of Limbo technology (Cellulis S.L.) offers an overall safe alternative for cell banking and direct infusion of cryopreserved cell products into patients.

Estimation of manufacturing development costs of cell-based therapies: a feasibility study

BACKGROUND AIMS

Cell-based therapies (CBTs) provide opportunities to treat rare and high-burden diseases. Manufacturing development of these innovative products is said to be complex and costly. However, little research is available providing insight into resource use and cost drivers. Therefore, this study aimed to assess the feasibility of estimating the cost of manufacturing development of two cell-based therapy case studies using a CBT cost framework specifically designed for small-scale cell-based therapies.

METHODS

A retrospective costing study was conducted in which the cost of developing an adoptive immunotherapy of Epstein-Barr virus-specific cytotoxic T lymphocytes (CTLs) and a pluripotent stem cell (PSC) master cell bank was estimated. Manufacturing development was defined as products advancing from technology readiness level 3 to 6. The study was conducted in a Scottish facility. Development steps were recreated via developer focus groups. Data were collected from facility administrative and financial records and developer interviews.

RESULTS

Application of the manufacturing cost framework to retrospectively estimate the manufacturing design cost of two case studies in one Scottish facility appeared feasible. Manufacturing development cost was estimated at £1,201,016 for CTLs and £494,456 for PSCs. Most costs were accrued in the facility domain (56% and 51%), followed by personnel (20% and 32%), materials (19% and 15%) and equipment (4% and 2%).

CONCLUSIONS

Based on this study, it seems feasible to retrospectively estimate resources consumed in manufacturing development of cell-based therapies. This fosters inclusion of cost in the formulation and dissemination of best practices to facilitate early and sustainable patient access and inform future cost-conscious manufacturing design decisions.

Cord blood beyond transplantation: can we use the experience to advance all cell therapies?

Unrelated cord blood (CB) units, already manufactured, fully tested and stored, are high-quality products for haematopoietic stem cell transplantation and cell therapies, as well as an optimal starting material for cell expansion, cell engineering or cell re-programming technologies. CB banks have been pioneers in the development and implementation of Current Good Manufacturing Practices for cell-therapy products. Sharing their technological and regulatory experience will help advance all cell therapies, CB-derived or not, particularly as they transition from autologous, individually manufactured products to stored, 'off-the shelf' treatments. Such strategies will allow broader patient access and wide product utilisation.

Patient-Specific Bone Particles Bioprinting for Bone Tissue Engineering

Although bioinks with both high printability and shape fidelity while maintaining high cell viability are developed, the biofunctionality of the resulting bioprinted construct is often overlooked. To address this, a methacrylated gelatin (GelMA)-based bioink biofunctionalized with bone particles (BPs) is developed as a personalized treatment strategy for bone regeneration. The bioink consists of incorporating BPs of various sizes (0-500 µm) in GelMA at various concentrations (ranging from 5 to 15% w/v). The printability of the bioink is systematically investigated and it is demonstrated that a 15% w/v BP-loading results in high print quality for 10% and 12.5% GelMA concentrations. Rheological evaluation reveals a strong shear thinning behavior essential for printing and a high gel strength in bioink with 15% w/v 0-500 µm BPs for both GelMA concentrations. In addition, the printability of the bioink and the metabolic activity of the resulting scaffolds are dependent on both the concentration of hydrogel and size of the BPs. Importantly, the cells initially contained in the BPs are able to migrate and colonize the bioprinted scaffold while maintaining their capacity to express early osteogenic markers. This study demonstrates the feasibility of bioprinted viable BPs and may have some potential for chairside clinical translation.