Current challenges in cell and gene therapy: a joint view from the European Committee of the International Society for Cell & Gene Therapy (ISCT) and the European Society for Blood and Marrow Transplantation (EBMT).

Cell and gene therapy poses evolving challenges. The current article summarizes the discussions held by European Regional Committee of the International Society for Cell & Gene Therapy and the European Society for Blood and Marrow Transplantation (EBMT) on the current challenges in this field, focusing on the European setting. This article emphasizes the imperative assessment of real-world cell and gene therapy activity, advocating for expanded registries beyond hematopoietic transplantation and chimeric antigen receptor-T-cell therapy. Accreditation's role in ensuring standardized procedures, as exemplified by JACIE (The Joint Accreditation Committee of ISCT-Europe and EBMT), is crucial for safety. Access to commercial products and reimbursement variations among countries underscore the need for uniform access to advanced therapy medical products (ATMPs). Academic product development and point-of-care manufacturing face barriers to patient access. Hospital Exemption's potential, demonstrated by some initial experiences, may increase patient accessibility in individual situations. Regulatory challenges, including the ongoing European ATMPs legislation review, necessitate standardized criteria for Hospital Exemption and mandatory reporting within registries. Efforts to combat unproven therapies and fraud involve collaboration between scientific societies, regulatory bodies and patient groups. Finally, is important to highlight the vital role of education and workforce development in meeting the escalating demand for specialized professionals in the ATMP field. Collaboration among scientific societies, academic institutions, industry, regulatory bodies and patient groups is crucial for overcoming all these challenges to increase gene and cell therapy activity in Europe.

Cell and gene therapy investment: evolution and future outlook on investor perspectives.

BACKGROUND AIMS: To better understand the attitudes and behaviors of investors involved in funding cell and gene therapy (CGT) businesses, the Business Development and Finance) subcommittee of International Society for Cell and Gene Therapy, in collaboration with Truist Securities, conducted a broad survey of the investment community in late 2021. METHODS: This survey follows a similar study that this group executed in 2018, and the longitudinal comparisons between the two time periods provide insights into how investor behavior in the CGT field has evolved. RESULTS: The vast majority of investor respondents are specialist biotech investors who are primarily active in deploying capital in North America and Europe. There was a notable increase in the proportion of investors actively deploying capital in China and Japan between 2018 and 2021. The percentage of respondents' portfolios dedicated to CGT companies has also increased in this period, reflecting a noteworthy trend in the therapeutic landscape. CONCLUSIONS: Clinically significant data remain the dominant force behind investment decisions, whereas competition from other drug modalities has now emerged as the most-cited barrier to making a CGT investment, eclipsing safety concerns as the most significant barrier to investment in 2018. Concerns around manufacturing and scale-up have also increased in prominence amongst the investment community. Gene-editing technologies are attracting investors as the most compelling new CGT technology. This survey also revealed that most investors expect to increase their level of investment in allogeneic technologies relative to autologous products in the coming years.

Lentiviral vector determinants of anion-exchange chromatography elution heterogeneity.

The demand for Lentiviral Vector (LV) drug substance is increasing. However, primary capture using convective anion-exchange chromatography remains a significant manufacturing challenge. This stems from a poor understanding of the complex adsorption behaviors linked to LVs intricate and variable structure, such as high binding heterogeneity which is typically characterized by a gradient elution profile consisting of two peaks. Understanding which LV structural components drive these phenomena is therefore crucial for rational process design. This work identifies the key LV envelope components responsible for binding to quaternary-amine membrane adsorbents. Eliminating the pseudotype protein (Vesicular Stomatitis Virus G glycoprotein [VSV-G]) did not impact the heterogenous two-peak elution profile, suggesting it is not a major binding species. Digestion of envelope glycosaminoglycans (GAGs), present on proteoglycans, leads to a dramatic reduction in the proportion of vector eluted in peak 2, decreasing from 50% to 3.1%, and a threefold increase in peak 1 maximum. Data from reinjection experiments point towards interparticle envelope heterogeneity from discrete LV populations, where the two-peak profile emerges from a subpopulation of LVs interacting via highly charged GAGs (peak 2) along with a weaker binding population likely interacting through the phospholipid membrane and envelope protein (peak 1).

Development of a Rapid Adeno-Associated Virus (AAV) Identity Testing Platform through Comprehensive Intact Mass Analysis of Full-Length AAV Capsid Proteins.

Adeno-associated viruses (AAVs) are commonly used as vectors for the delivery of gene therapy targets. Characterization of AAV capsid proteins (VPs) and their post-translational modifications (PTMs) have become a critical attribute monitored to evaluate product quality. Liquid chromatography-mass spectrometry (LC-MS) analysis of intact AAV VPs provides both quick and reliable serotype identification as well as proteoform information on each VP. Incorporating these analytical strategies into rapid good manufacturing practice (GMP)-compliant workflows containing robust, but simplified, data processing methods is necessary to ensure effective product quality control (QC) during production. Here, we present a GMP-compliant LC-MS workflow for the rapid identification and in-depth characterization of AAVs. Hydrophilic interaction liquid chromatography (HILIC) MS with difluoroacetic acid as a mobile phase modifier is utilized to achieve the intact separation and identification of AAV VPs and their potential proteoforms. Peptide mapping is performed to confirm PTMs identified during intact VP analysis and for in-depth PTM characterization. The intact separations platform is then incorporated into a data processing workflow developed using GMP-compliant software capable of rapid AAV serotype identification and, if desired, specific serotype PTM monitoring and characterization. Such a platform provides product QC capabilities that are easily accessible in a regulatory setting.

Size distribution analysis of residual host cell DNA fragments in lentivirus by CGE-LIF.

During the production of cell and gene therapy products, residual host cell DNA (HCD) could cause safety risks of the biological products, and the longer the residual HCD fragment, the greater the risk to the human body. For this reason, it was necessary to develop an effective method for the size distribution analysis of residual HCD fragments with high accuracy and sensitivity. In this study, capillary gel electrophoresis with laser-induced fluorescence detector (CGE-LIF) was used to analyze the size distribution of residual HCD fragments in lentivirus products. The results confirmed that lentiviral RNA genome could interfere with the size distribution analysis of residual HCD fragments. By optimizing the amount of RNase I and digestion time in sample pretreatment process, the interfere of RNA genome could be avoided. The specificity, precision, accuracy, linear range, the detection of limit (LOD), and the quantification of limit (LOQ) of CGE-LIF method were also validated. The results showed that the CGE-LIF method had a good performance both in terms of specificity and reproducibility. The intra- and inter-day relative standard deviations of migration time and corrected peak area were all less than 1% and 2%, respectively. The 200 bp DNA marker had a good linearity between 50 and 1000 pg/ml. The LOD and LOQ of 200 bp DNA marker were 2.59 and 8.64 pg/ml, respectively. In addition, this method was successfully used to analyze the size distribution analysis of residual HCD fragments in lentivirus products with different production processes.

Comparison of guidelines for biological ancillary materials used for the manufacture of gene and cellular therapy products in Asia.

BACKGROUND AIMS: Although biologiocal ancillay materials (AMs) have specific risk associated with their derivations, it plays key role to manufature cell and gene therapy (CGT) products. It is important to understand the regulation relevant to AMs for developers. METHODS: The authors investigated the guidelines and pharmacopeia (hereinafter referred to as "guidelines") for biological AMs used for the manufacture of CGT products in Asia (China, India, Japan, Korea and Taiwan). In addition, the authors benchmarked the relevant guidelines in the United States (US) and European Union (EU). RESULTS AND DISCUSSIONS: The guidelines could be classified into two types based on whether specific AMs are scoped: (i) general guidelines for risk assessment of AMs and (ii) guidelines for specific AMs. The authors compared the risk categories for each type of AM provided in the general guidelines between the US and China and the specific requirements for bovine serum and trypsin in the guidelines of China, Japan, Taiwan, US and EU. The authors further compiled in-depth descriptions of the respective regulations in China, India, Japan, Korea and Taiwan. There is limited availability of some guidelines for specific AMs. Moreover, there are no common requirements established across the surveyed countries and regions. Therefore, the authors suggest a risk assessment approach for AMs with consideration of their biological origin and traceability, production steps applied and ability to control or remove AMs from the final medicinal product over the CGT manufacturing process.

Non-clinical, quality and environmental impact assessments of cell and gene therapy products: Report on the 5th Asia Partnership Conference of Regenerative Medicine - April 7, 2022.

The 5th Asia Partnership Conference of Regenerative Medicine (APACRM) was held online on April 7, 2022 to promote regulatory harmonization of regenerative medicine products throughout Asia. The recognition of domestic regulatory guidelines within each country and region and the underpinning rationales are important initial steps toward the harmonization of regulations. The 5th APACRM featured open dialog regarding non-clinical, quality and environmental impact assessment settings for cell and gene therapy products through presentations from the industry and panel discussions with regulatory agencies. The latest updates on regenerative medicine fields in each country and region were also introduced. This paper summarizes the proceedings of the 5th APACRM for public dissemination to foster future discussion.

Time-dependent sorption behavior of lentiviral vectors during anion-exchange chromatography.

Use of lentiviral vectors (LVs) in clinical Cell and Gene Therapy applications is growing. However, functional product loss during capture chromatography, typically anion-exchange (AIEX), remains a significant unresolved challenge for the design of economic processes. Despite AIEX's extensive use, variable performance and generally low recovery is reported. This poor understanding of product loss mechanisms highlights a significant gap in our knowledge of LV adsorption and other types of vector delivery systems. This work demonstrates HIV-1-LV recovery over quaternary-amine membrane adsorbents is a function of time in the adsorbed state. Kinetic data for product loss in the column bound state was generated. Fitting a second order-like rate model, we observed a rapid drop in functional recovery due to increased irreversible binding for vectors encoding two separate transgenes ( t Y 1 / 2 ${t}_{{Y}_{1/2}}$ = 12.7 and 18.7 min). Upon gradient elution, a two-peak elution profile implicating the presence of two distinct binding subpopulations is observed. Characterizing the loss kinetics of these two subpopulations showed a higher rate of vector loss in the weaker binding peak. This work highlights time spent in the adsorbed state as a critical factor impacting LV product loss and the need for consideration in LV AIEX process development workflows.

Ethical and practical considerations for cell and gene therapy toward an HIV cure: findings from a qualitative in-depth interview study in the United States.

BACKGROUND: HIV cure research involving cell and gene therapy has intensified in recent years. There is a growing need to identify ethical standards and safeguards to ensure cell and gene therapy (CGT) HIV cure research remains valued and acceptable to as many stakeholders as possible as it advances on a global scale. METHODS: To elicit preliminary ethical and practical considerations to guide CGT HIV cure research, we implemented a qualitative, in-depth interview study with three key stakeholder groups in the United States: (1) biomedical HIV cure researchers, (2) bioethicists, and (3) community stakeholders. Interviews permitted evaluation of informants' perspectives on how CGT HIV cure research should ethically occur, and were transcribed verbatim. We applied conventional content analysis focused on inductive reasoning to analyze the rich qualitative data and derive key ethical and practical considerations related to CGT towards an HIV cure. RESULTS: We interviewed 13 biomedical researchers, 5 community members, and 1 bioethicist. Informants generated considerations related to: perceived benefits of CGT towards an HIV cure, perceived risks, considerations necessary to ensure an acceptable benefit/risk balance, CGT strategies considered unacceptable, additional ethical considerations, and considerations for first-in-human CGT HIV cure trials. Informants also proposed important safeguards to developing CGT approaches towards an HIV cure, such as the importance of mitigating off-target effects, mitigating risks associated with long-term duration of CGT interventions, and mitigating risks of immune overreactions. CONCLUSION: Our study identified preliminary considerations for CGT-based HIV cure across three key stakeholder groups. Respondents identified an ideal cure strategy as one which would durably control HIV infection, protect the individual from re-acquisition, and eliminate transmission to others. Known and unknown risks should be anticipated and perceived as learning opportunities to preserve and honor the altruism of participants. Preclinical studies should support these considerations and be transparently reviewed by regulatory experts and peers prior to first-in-human studies. To protect the public trust in CGT HIV cure research, ethical and practical considerations should be periodically revisited and updated as the science continues to evolve. Additional ethics studies are required to expand stakeholder participation to include traditionally marginalized groups and clinical care providers.

Standards efforts and landscape for rapid microbial testing methodologies in regenerative medicine.

The Standards Coordinating Body for Gene, Cell, and Regenerative Medicines and Cell-Based Drug Discovery (SCB) supports the development and commercialization of regenerative medicine products by identifying and addressing industry-wide challenges through standards. Through extensive stakeholder engagement, the implementation of rapid microbial testing methods (RMTMs) was identified as a high-priority need that must be addressed to facilitate more timely release of products. Since 2017, SCB has coordinated efforts to develop standards for this area through surveys, weekly meetings, workshops, leadership in working groups and participation in standards development organizations. This article describes the results of these efforts and discusses the current landscape of RMTMs for regenerative medicine products. Based on discussions with stakeholders across the field, an overview of traditional culture-based methods and limitations, alternative microbial testing technologies and current challenges, fit-for-purpose rapid microbial testing and case studies, risk-based strategies for selection of novel rapid microbial test methods and ongoing standards efforts for rapid microbial testing are captured here. To this end, SCB is facilitating several initiatives to address challenges associated with rapid microbial testing for regenerative medicine products. Two documentary standards are under development: an International Organization for Standardization standard to provide the framework for a risk-based approach to selecting fit-for-purpose assays primarily intended for cell and gene therapy products and an ASTM standard guide focused on sampling methods for microbial testing methods in tissue-engineered medical products. Working with the National Institute of Standards and Technology, SCB expects to facilitate the process of developing publicly available microbial materials for inter-laboratory testing. These studies will help collect the data necessary to facilitate validation of novel rapid methods. Finally, SCB has been working to increase awareness of, dialog about and participation in efforts to develop standards in the regenerative medicine field.

Transitioning from development to commercial: risk-based guidance for critical materials management in cell therapies.

A key hurdle to ensuring patient access to cell and gene therapies (CGTs) and continued growth of the industry is the management of raw materials. The combination of rapid growth, individual product and process complexity and limited industry-specific guidance or awareness presents non-obvious risk mitigation challenges for transitioning from development to clinical application. Understanding, assessing and mitigating the varied raw material risks for CGT products during product and clinical development are critical for ensuring smooth transitions into commercialization and for preventing interruption of product supply to patients. This article presents a risk-based approach driven by concerns for patient safety that can help focus and coordinate efforts to address the most critical risk factors. Highlighted are some of the highest risk materials common to the manufacture of many CGTs, including the primary starting material, culture media, reagents and single-use components. Using a hypothetical gene-edited cell therapy as an example, we describe the general manufacturing process and subsequently incorporate the described methodology to perform a sample risk assessment. The practical approach described herein is intended to assist CGT manufacturers and suppliers in actively assessing materials early in development to provide a basic starting point for mitigating risks experienced when translating CGT products for clinical and long-term commercial application.

Centralised versus decentralised manufacturing and the delivery of healthcare products: A United Kingdom exemplar.

BACKGROUND: The cell and gene therapy (CGT) field is at a critical juncture. Clinical successes have underpinned the requirement for developing manufacturing capacity suited to patient-specific therapies that can satisfy the eventual demand post-launch. Decentralised or 'redistributed' manufacturing divides manufacturing capacity across geographic regions, promising local, responsive manufacturing, customised to the end user, and is an attractive solution to overcome challenges facing the CGT manufacturing chain. METHODS: A study was undertaken building on previous, so far unpublished, semi-structured interviews with key opinion leaders in advanced therapy research, manufacturing and clinical practice. The qualitative findings were applied to construct a cost of goods model that permitted the cost impact of regional siting to be combined with variable and fixed costs of manufacture of a mesenchymal stromal cell product. RESULTS: Using the United Kingdom as an exemplar, cost disparities between regions were examined. Per patient dose costs of ~£1,800 per 75,000,000 cells were observed. Financial savings from situating the facility outside of London allow 25-41 additional staff or 24-35 extra manufacturing vessels to be employed. Decentralised quality control to mitigate site-to-site variation was examined. Partial decentralisation of quality control was observed to be financially possible and an attractive option for facilitating release 'at risk'. DISCUSSION: There are important challenges that obstruct the easy adoption of decentralised manufacturing that have the potential to undermine the market success of otherwise promising products. By using the United Kingdom as an exemplar, the modelled data provide a framework to inform similar regional policy considerations across other global territories.

Regulatory perspectives of Japan.

In this article, the 2013 regenerative medicine laws and regulations in Japan are addressed. The Regenerative Medicine Promotion Law was promulgated in May 2013 to promote comprehensive measures from research and development to practical use of regenerative medicines. In line with this purpose, two acts have been passed by the National Diet in November 2013. One is the Act on the Safety of Regenerative Medicine, which classifies regenerative medicines based on risk. Additionally this Act stipulates the procedures for offering regenerative medicines, the measures for appropriate provision of the regenerative medicines, and authorization to manufacture designated cellular therapeutic products for therapeutic use. The other is the Act on Pharmaceuticals and Medical Devices, previously named the Pharmaceutical Affairs Act, which establishes regulations tailored to the characteristics of regenerative medicinal products, including an expedited approval system.

Generation of induced pluripotent stem cells by using a mammalian artificial chromosome expression system.

Direct reprogramming of mouse fibroblasts into induced pluripotent stem cells (iPS) was achieved recently by overexpression of four transcription factors encoded by retroviral vectors. Most of the virus vectors, however, may cause insertional mutagenesis in the host genome and may also induce tumor formation. Therefore, it is very important to discover novel and safer, non-viral reprogramming methods. Here we describe the reprogramming of somatic cells into iPS cells by a novel protein-based technique. Engineered Oct4, Sox2 and Klf4 transcription factors carrying an N-terminal Flag-tag and a C-terminal polyarginine tail were synthesized by a recently described mammalian artificial chromosome expression system (ACEs). This system is suitable for the high-level production of recombinant proteins in mammalian tissue culture cells. Recombinant proteins produced in this system contain all the post-translational modifications essential for the stability and the authentic function of the proteins. The engineered Oct4, Sox2 and Klf4 proteins efficiently induced the reprogramming of mouse embryonic fibroblasts by means of protein transduction. This novel method allows for the generation of iPS cells, which may be suitable for therapeutic applications in the future.

The highest-cost Medicaid enrollees with sickle cell disease had annual health care expenditures nearing $200 000.

Sickle cell disease (SCD) is a painful chronic blood disorder that causes serious complications and comorbidities, often leading to premature death. SCD impacts millions of people worldwide, including an estimated 100 000 in the United States, most of whom are Black or Latino. We analyzed Medicaid enrollment, claims, and encounter data via the Transformed Medicaid Statistical Information System (T-MSIS) to examine the 2021 health care utilization and spending of Medicaid enrollees with SCD. Our analysis found that Medicaid enrollees with SCD have high annual medical and pharmacy expenditures that are not evenly distributed across the population. Among the most severe enrollees with genotypes eligible for clinical trials, those in the top 5% of health care spending incurred, on average, nearly $200 000 per year for this chronic condition.

Current status and future prospective of breast cancer immunotherapy.

The immune system is complicated, interconnected, and offers a powerful defense system that protects its host from foreign pathogens. Immunotherapy involves boosting the immune system to kill cancer cells, and nowadays, is a major emerging treatment for cancer. With the advances in our understanding of the immunology of cancer, there has been an explosion of studies to develop and evaluate therapies that engage the immune system in the fight against cancer. Nevertheless, conventional therapies have been effective in reducing tumor burden and prolonging patient life, but the overall efficacy of these treatment regimens has been somewhat mixed and often with severe side effects. A common reason for this is the activation of molecular mechanisms that lead to apoptosis of anti-tumor effector cells. The competency to block tumor escape entirely depends on our understanding of the cellular and molecular pathways which operate in the tumor microenvironment. Numerous strategies have been developed for activating the immune system to kill tumor cells. Breast cancer is one of the major causes of cancer death in women, and is characterized by complex molecular and cellular events that closely intertwine with the host immune system. In this regard, predictive biomarkers of immunotherapy, use of nanotechnology, personalized cancer vaccines, antibodies to checkpoint inhibitors, engineered chimeric antigen receptor-T cells, and the combination with other therapeutic modalities have transformed cancer therapy and optimized the therapeutic effect. In this chapter, we will offer a holistic view of the different therapeutic modalities and recent advances in immunotherapy. Additionally, we will summarize the recent advances and future prospective of breast cancer immunotherapies, as a case study.

Challenges and Lessons Learned in Autologous Chimeric Antigen Receptor T-Cell Therapy Development from a Statistical Perspective.

Chimeric antigen receptor (CAR) T-cell therapy is a human gene therapy product where T cells from a patient are genetically modified to enable them to recognize desired target antigen(s) more effectively. In recent years, promising antitumor activity has been seen with autologous CAR T cells. Since 2017, six CAR T-cell therapies for the treatment of hematological malignancies have been approved by the Food and Drug Administration (FDA). Despite the rapid progress of CAR T-cell therapies, considerable statistical challenges still exist for this category of products across all phases of clinical development that need to be addressed. These include (but not limited to) dose finding strategy, implementation of the estimand framework, use of real-world data in contextualizing single-arm CAR T trials, analysis of safety data and long-term follow-up studies. This paper is the first step in summarizing and addressing these statistical hurdles based on the development of the six approved CAR T-cell products.

Cell and Gene Therapies: Challenges in Designing Extractables and Leachables Studies and Conducting Safety Assessments.

Over the past decade, Cell and Gene Therapies (C>) have been an emerging therapeutic area with more than twenty C> drug products approved and over 1000 registered trials. The remarkable progress in these modalities brings new challenges for scientists who evaluate manufacturing and storage materials, including risk assessments for extractables and leachables (E&L). Establishing a business process to qualify materials for these applications is an important risk mitigation strategy in support of these assessments. Process validation verifying process performance and product quality requirements using qualified materials also ensures that leachables from the materials do not result in an impact to process and product. The authors provide an overview of available guidelines and publications relevant to E&L risk assessments that can be used to support ex vivo C> products, highlighting gaps and standardization needs in the areas of biocompatibility and extractables conditions. Finally, the authors present leachable testing strategies, relevant to the specific manufacturing and storage conditions of C> products, and safety assessment considerations for organic and inorganic chemical entities.

Assessing biologic/toxicologic effects of extractables from plastic contact materials for advanced therapy manufacturing using cell painting assay and cytotoxicity screening.

Plastic components are essential in the pharmaceutical industry, encompassing container closure systems, laboratory handling equipment, and single-use systems. As part of their material qualification process, studies on interactions between plastic contact materials and process solutions or drug products are conducted. The assessment of single-use systems includes their potential impact on patient safety, product quality, and process performance. This is particularly crucial in cell and gene therapy applications since interactions with the plastic contact material may result in an adverse effect on the isolated therapeutic human cells. We utilized the cell painting assay (CPA), a non-targeted method, for profiling the morphological characteristics of U2OS human osteosarcoma cells in contact with chemicals related to plastic contact materials. Specifically, we conducted a comprehensive analysis of 45 common plastic extractables, and two extracts from single-use systems. Results of the CPA are compared with a standard cytotoxicity assay, an osteogenesis differentiation assay, and in silico toxicity predictions. The findings of this feasibility study demonstrate that the device extracts and most of the tested compounds do not evoke any measurable biological changes on the cells (induction ≤ 5%) among the 579 cell features measured at concentrations ≤ 50 µM. CPA can serve as an important assay to reveal unique information not accessible through quantitative structure-activity relationship analysis and vice versa. The results highlight the need for a combination of in vitro and in silico methods in a comprehensive assessment of single-use equipment utilized in advanced therapy medicinal products manufacturing.

Real-world evidence for coverage determination of treatments for rare diseases.

Health technology assessment (HTA) decisions for pharmaceuticals are complex and evolving. New rare disease treatments are often approved more quickly through accelerated approval schemes, creating more uncertainties about clinical evidence and budget impact at the time of market entry. The use of real-world evidence (RWE), including early coverage with evidence development, has been suggested as a means to support HTA decisions for rare disease treatments. However, the collection and use of RWE poses substantial challenges. These challenges are compounded when considered in the context of treatments for rare diseases. In this paper, we describe the methodological challenges to developing and using prospective and retrospective RWE for HTA decisions, for rare diseases in particular. We focus attention on key elements of study design and analyses, including patient selection and recruitment, appropriate adjustment for confounding and other sources of bias, outcome selection, and data quality monitoring. We conclude by offering suggestions to help address some of the most vexing challenges. The role of RWE in coverage and pricing determination will grow. It is, therefore, necessary for researchers, manufacturers, HTA agencies, and payers to ensure that rigorous and appropriate scientific principles are followed when using RWE as part of decision-making.