Development of a cell-based medicinal product: regulatory structures in the European Union

Cell Therapy of Vascular and Neuropathic Complications of Diabetes: Can We Avoid Limb Amputation?

Globally, a leg is amputated approximately every 30 seconds, with an estimated 85 percent of these amputations being attributed to complications arising from diabetic foot ulcers (DFU), as stated by the American Diabetes Association. Peripheral arterial disease (PAD) is a risk factor resulting in DFU and can, either independently or in conjunction with diabetes, lead to recurring, slow-healing ulcers and amputations. According to guidelines amputation is the recommended treatment for patients with no-option critical ischemia of the limb (CTLI). In this article we propose cell therapy as an alternative strategy for those patients. We also suggest the optimal time-frame for an effective therapy, such as implanting autologous mononuclear cells (MNCs), autologous and allogeneic mesenchymal stromal cells (MSC) as these treatments induce neuropathy relief, regeneration of the blood vessels and tissues, with accelerated ulcer healing, with no serious side effects, proving that advanced therapy medicinal product (ATMPs) application is safe and effective and, hence, can significantly prevent limb amputation.

Lifelike Transformative Materials for Biohybrid Implants: Inspired by Nature, Driven by Technology

Today's living world is enriched with a myriad of natural biological designs, shaped by billions of years of evolution. Unraveling the construction rules of living organisms offers the potential to create new materials and systems for biomedicine. From the close examination of living organisms, several concepts emerge: hierarchy, pattern repetition, adaptation, and irreducible complexity. All these aspects must be tackled to develop transformative materials with lifelike behavior. This perspective article highlights recent progress in the development of transformative biohybrid systems for applications in the fields of tissue regeneration and biomedicine. Advances in computational simulations and data-driven predictions are also discussed. These tools enable the virtual high-throughput screening of implant design and performance before committing to fabrication, thus reducing the development time and cost of biomimetic and biohybrid constructs. The ongoing progress of imaging methods also constitutes an essential part of this matter in order to validate the computation models and enable longitudinal monitoring. Finally, the current challenges of lifelike biohybrid materials, including reproducibility, ethical considerations, and translation, are discussed. Advances in the development of lifelike materials will open new biomedical horizons, where perhaps what is currently envisioned as science fiction will become a science-driven reality in the future.

Desert Endemic Plants in Algeria: A Review on Traditional Uses, Phytochemistry, Polyphenolic Compounds and Pharmacological Activities

Due to their robust antioxidant capabilities, potential health benefits, wide variety of biological activities, and strong antioxidant qualities, phenolic compounds are substances that have drawn considerable attention in recent years. The main goal of the review is to draw attention to saharian Algerian medicinal plants and the determination of their bioactivity (antioxidant, anti-cancer, and anti-inflammatory importance), and to present their chemical composition as well as in vivo and in vitro studies, clinical studies, and other studies confirming their real impact on human health. Research results have revealed a rich variety of medicinal plants used to treat various disease states in this region. Based on in vivo and in vitro studies, biological activity, and clinical studies, a list of 34 species of desert plants, belonging to 20 botanical families, useful both in preventive actions and in the treatment of neoplastic diseases has been established, and polyphenolic compounds have been identified as key to the health potential of endemic diseases and desert plants. It has been shown that people who follow a diet rich in polyphenols are less prone to the risk of many cancers and chronic diseases, such as obesity and diabetes. In view of the increasing antioxidant potential of these plant species, as well as the increasing trade in herbal products from the Sahara region, phytosanitary and pharmaceutical regulations must change in this respect and should be in line with Trade Related Aspects of Intellectual Property Rights (TRIPS), and the sustainable use and development of plant products must be addressed at the same time.

Mesenchymal Stem/Stromal Cells and Their Paracrine Activity-Immunomodulation Mechanisms and How to Influence the Therapeutic Potential

With high clinical interest to be applied in regenerative medicine, Mesenchymal Stem/Stromal Cells have been widely studied due to their multipotency, wide distribution, and relative ease of isolation and expansion in vitro. Their remarkable biological characteristics and high immunomodulatory influence have opened doors to the application of MSCs in many clinical settings. The therapeutic influence of these cells and the interaction with the immune system seems to occur both directly and through a paracrine route, with the production and secretion of soluble factors and extracellular vesicles. The complex mechanisms through which this influence takes place is not fully understood, but several functional manipulation techniques, such as cell engineering, priming, and preconditioning, have been developed. In this review, the knowledge about the immunoregulatory and immunomodulatory capacity of MSCs and their secretion products is revisited, with a special focus on the phenomena of migration and homing, direct cell action and paracrine activity. The techniques for homing improvement, cell modulation and conditioning prior to the application of paracrine factors were also explored. Finally, multiple assays where different approaches were applied with varying success were used as examples to justify their exploration.

Associação Brasileira de Hematologia, Hemoterapia e Terapia Celular Consensus on genetically modified cells. Special Article: Advanced therapy medicinal products in Brazil: regulatory panorama

Advanced therapy medicinal products, considered special medications, requires Anvisa approval for use and commercialization in Brazil. They include the advanced cellular therapy products, tissue engineering products and gene therapy products, which due to their complexity involve innovation and risks, optimized regulatory channels for their development and life cycle monitoring. The scientific elements and the compliance with applicable regulatory aspects are fundamental pillars for the advancement of clinical trials, the positive evidence of the benefit-risk profile and the definition of the critical quality attributes, from the perspective of making safe, effective and high-quality products available to the population. The approval models of these products in Brazil adapt to the specificities and characteristics of the technology and the patient target population, with accelerated regulatory analyses, use in emergency situations by risk controls and specific monitoring mechanisms, principally those related to rare diseases without other therapeutic alternatives. The opportune access to the advance therapy product with safety, efficacy and quality involves innovative normative elements that include the long-term follow-up of the safety and efficacy and of the adaptive pharmacovigilance requisites, as well as the traceability mechanisms for the start-off materials, products and patients.

Isolation, Culture, Cryopreservation, and Preparation of Umbilical Cord-Derived Mesenchymal Stem Cells as a Final Cellular Product Under Good Manufacturing Practices-Compliant Conditions

Mesenchymal stem cells have gained popularity in cell-based therapies due to their regenerative capabilities, immunomodulation properties, and paracrine activity through trophic factors. It is of utmost importance to establish clinical-grade procedures for the preparation of the mesenchymal stem cells for clinical applications. Here, we describe detailed procedures for isolation, culture, cryopreservation, and preparation of mesenchymal stem cells derived from umbilical cord as a final product under good manufacturing practices-compliant conditions.

Tissue Engineering in Musculoskeletal Tissue: A Review of the Literature

Tissue engineering refers to the attempt to create functional human tissue from cells in a laboratory. This is a field that uses living cells, biocompatible materials, suitable biochemical and physical factors, and their combinations to create tissue-like structures. To date, no tissue engineered skeletal muscle implants have been developed for clinical use, but they may represent a valid alternative for the treatment of volumetric muscle loss in the near future. Herein, we reviewed the literature and showed different techniques to produce synthetic tissues with the same architectural, structural and functional properties as native tissues.

Role of Mesenchymal Stromal Cells as Therapeutic Agents: Potential Mechanisms of Action and Implications in Their Clinical Use

Due to the great therapeutic interest that involves the translation of mesenchymal stromal cells (MSCs) into clinical practice, they have been widely studied as innovative drugs, in order to treat multiple pathologies. MSC-based cell therapy involves the administration of MSCs either locally or systemically into the receptor body where they can traffic and migrate towards the affected tissue and participate in the process of healing. The therapeutic effects of MSCs compromise of different mechanisms such as the functional integration of differentiated MSCs into diseased host tissue after transplantation, their paracrine support, and their impact on the regulation of both the innate and the acquired immune system. Here, we establish and provide recent advances about the principal mechanisms of action through which MSCs can perform their activity and effect as a therapeutic tool. The purpose of this review is to examine and discuss the MSCs capacity of migration, their paracrine effect, as well as MSC-mediated modifications on immune cell responses.

An overview of international regulatory frameworks for mesenchymal stromal cell-based medicinal products: From laboratory to patient

Human mesenchymal stromal cells (hMSCs) are emerging as one of the most important cell types in advanced therapies and regenerative medicine due to their great therapeutic potential. The development of hMSC-based products focuses on the use of hMSCs as biological active substances, and they are considered medicinal products by the primary health agencies worldwide. Due to their regulatory status, the development of hMSC-based products is regulated by specific criteria that range from the design phase, nonclinical studies, clinical studies, to the final registration and approval. Patients should only be administered hMSC-based products within the framework of a clinical trial or after the product has obtained marketing authorization; in both cases, authorization by health authorities is usually required. Considering the above, this paper describes the current general regulatory requirements for hMSC-based products, by jurisdiction, to be implemented throughout their entire development process. These measures may provide support for researchers from both public and private entities and academia to optimize the development of these products and their subsequent marketing, thereby improving access to them by patients.

Principal Criteria for Evaluating the Quality, Safety and Efficacy of hMSC-Based Products in Clinical Practice: Current Approaches and Challenges

Human Mesenchymal Stem Cells (hMSCs) play an important role as new therapeutic alternatives in advanced therapies and regenerative medicine thanks to their regenerative and immunomodulatory properties, and ability to migrate to the exact area of injury. These properties have made hMSCs one of the more promising cellular active substances at present, particularly in terms of the development of new and innovative hMSC-based products. Currently, numerous clinical trials are being conducted to evaluate the therapeutic activity of hMSC-based products on specific targets. Given the rapidly growing number of hMSC clinical trials in recent years and the complexity of these products due to their cellular component characteristics and medicinal product status, there is a greater need to define more stringent, specific, and harmonized requirements to characterize the quality of the hMSCs and enhance the analysis of their safety and efficacy in final products to be administered to patients. These requirements should be implemented throughout the manufacturing process to guarantee the function and integrity of hMSCs and to ensure that the hMSC-based final product consistently meets its specifications across batches. This paper describes the principal phases involved in the design of the manufacturing process and updates the specific technical requirements needed to address the appropriate clinical use of hMSC-based products. The challenges and limitations to evaluating the safety, efficacy, and quality of hMSCs have been also reviewed and discussed.

Cost-Effective, Safe, and Personalized Cell Therapy for Critical Limb Ischemia in Type 2 Diabetes Mellitus

Cell therapy is a progressively growing field that is rapidly moving from preclinical model development to clinical application. Outcomes obtained from clinical trials reveal the therapeutic potential of stem cell-based therapy to deal with unmet medical treatment needs for several disorders with no therapeutic options. Among adult stem cells, mesenchymal stem cells (MSCs) are the leading cell type used in advanced therapies for the treatment of autoimmune, inflammatory and vascular diseases. To date, the safety and feasibility of autologous MSC-based therapy has been established; however, their indiscriminate use has resulted in mixed outcomes in preclinical and clinical studies. While MSCs derived from diverse tissues share common properties depending on the type of clinical application, they markedly differ within clinical trials in terms of efficacy, resulting in many unanswered questions regarding the application of MSCs. Additionally, our experience in clinical trials related to critical limb ischemia pathology (CLI) shows that the therapeutic efficacy of these cells in different animal models has only been partially reproduced in humans through clinical trials. Therefore, it is crucial to develop new research to identify pitfalls, to optimize procedures and to clarify the repair mechanisms used by these cells, as well as to be able to offer a next generation of stem cell that can be routinely used in a cost-effective and safe manner in stem cell-based therapies targeting CLI.

Therapeutic strategies for skin regeneration based on biomedical substitutes

Regenerative medicine and tissue engineering (TE) have experienced significant advances in the development of in vitro engineered skin substitutes, either for replacement of lost tissue in skin injuries or for the generation of in vitro human skin models to research. However, currently available skin substitutes present different limitations such as expensive costs, abnormal skin microstructure and engraftment failure. Given these limitations, new technologies, based on advanced therapies and regenerative medicine, have been applied to develop skin substitutes with several pharmaceutical applications that include injectable cell suspensions, cell-spray devices, sheets or 3Dscaffolds for skin tissue regeneration and others. Clinical practice for skin injuries has evolved to incorporate these innovative applications to facilitate wound healing, improve the barrier function of the skin, prevent infections, manage pain and even to ameliorate long-term aesthetic results. In this article, we review current commercially available skin substitutes for clinical use, as well as the latest advances in biomedical and pharmaceutical applications used to design advanced therapies and medical products for wound healing and skin regeneration. We highlight the current progress in clinical trials for wound healing as well as the new technologies that are being developed and hold the potential to generate skin substitutes such as 3D bioprinting-based strategies.

Commercial Products for Osteochondral Tissue Repair and Regeneration

The osteochondral tissue represents a complex structure composed of four interconnected structures, namely hyaline cartilage, a thin layer of calcified cartilage, subchondral bone, and cancellous bone. Due to the several difficulties associated with its repair and regeneration, researchers have developed several studies aiming to restore the native tissue, some of which had led to tissue-engineered commercial products. In this sense, this chapter discusses the good manufacturing practices, regulatory medical conditions and challenges on clinical translations that should be fulfilled regarding the safety and efficacy of the new commercialized products. Furthermore, we review the current osteochondral products that are currently being marketed and applied in the clinical setting, emphasizing the advantages and difficulties of each one.

Clinical application of cell, gene and tissue therapies in Spain

Scientific and technical advances in the areas of biomedicine and regenerative medicine have enabled the development of new treatments known as "advanced therapies", which encompass cell therapy, genetics and tissue engineering. The biologic products that can be manufactured from these elements are classified from the standpoint of the Spanish Agency of Medication and Health Products in advanced drug therapies, blood products and transplants. This review seeks to provide scientific and administrative information for clinicians on the use of these biologic resources.

Adaptation through Collaboration: Developing Novel Platforms to Advance the Delivery of Advanced Therapies to Patients

For the nascent field of advanced therapies, collaboration will be a game-changer, turning scientific progress that was once unimaginable into transformative medical practice. Despite promise for lifelong management and even cure of disease, skepticism remains about the feasibility of their delivery to patients, fueling investment risks. With the potential for long-term effectiveness in need of frequent reassessment, current approaches to predict real-life drug performance bear little relevance, necessitating novel and iterative schemes to monitoring the benefit–risk profiles throughout the life span of advanced therapies. This work explains that reinventing an adoption route for Advanced Therapy Medicinal Products is as much about the scientific and clinical components, as it is about the organizational structures, requiring an unprecedented level of interactions between stakeholders not traditionally connected; from developers and regulators, to payers, patients, and funders. By reflecting on the successes and lessons learned from the growing space of global precompetitive consortia and public–private partnerships, as well as a number of emerging accelerated development pathways, this work aims to inform the foundations for a future roadmap that can smooth the path to approval, reimbursement, and access, while delivering value to all stakeholders. Echoing the growing demands to bring these transformative products to patients, it provides critical insights to enhance our capacity in three fundamental domains: deploying the operational flexibilities offered by the growing space of collaborations, utilizing emerging flexible and accelerated pathways to tackle challenges in quantifying long-term effectiveness, and building the necessary digital and clinical infrastructure for knowledge development.

Characteristics, applications and prospects of mesenchymal stem cells in cell therapy

Recent advances in the field of cell therapy and regenerative medicine describe mesenchymal stem cells (MSCs) as potential biological products due to their ability to self-renew and differentiate. MSCs are multipotent adult cells with immunomodulatory and regenerative properties, and, given their therapeutic potential, they are being widely studied in order to evaluate their viability, safety and efficacy. In this review, we describe the main characteristics and cellular sources of MSCs, in addition to providing an overview of their properties and current clinical applications, as well offering updated information on the regulatory aspects that define them as somatic cell therapy products. Cell therapy based on MSCs is offered nowadays as a pharmacological alternative, although there are still challenges to be addressed in this regard.

Development of cell therapy medicinal products by academic institutes

In the rapidly evolving fields of cellular immunotherapy, gene therapy and regenerative medicine, a wide range of promising cell therapy medicinal products are in clinical development. Most products originate from academic research and are explored in early exploratory clinical trials. However, the success rate toward approval for regular patient care is disappointingly low. In this paper, we define strengths and hurdles applying to the development of cell therapy medicinal products in academic institutes, and analyze why only a few promising cell therapies have reached late-stage clinical development. Subsequently, we provide recommendations to stakeholders involved in development of cell therapies to exploit their potential clinical benefit.

Are there specific translational challenges in regenerative medicine? Lessons from other fields

There is concern that translation 'from bench to bedside' within regenerative medicine (RM) will fail to materialize, or will be dismally slow, due to various challenges arising from the highly novel and disruptive nature of RM. In this article, we provide a summary of these challenges, and we critically engage with the notion that such challenges are specific to RM. It is important, we argue, not to overstate the exceptional nature of RM, as valuable lessons can be learned from elsewhere in medicine. Using several examples of technology adoption, we suggest that emerging RM products and procedures will have to work hard to find or create an adoption space if translation into the clinic is to be successful.

Deterministic and stochastic approaches in the clinical application of mesenchymal stromal cells (MSCs)

Mesenchymal stromal cells (MSCs) have enormous intrinsic clinical value due to their multi-lineage differentiation capacity, support of hemopoiesis, immunoregulation and growth factors/cytokines secretion. MSCs have thus been the object of extensive research for decades. After completion of many pre-clinical and clinical trials, MSC-based therapy is now facing a challenging phase. Several clinical trials have reported moderate, non-durable benefits, which caused initial enthusiasm to wane, and indicated an urgent need to optimize the efficacy of therapeutic, platform-enhancing MSC-based treatment. Recent investigations suggest the presence of multiple in vivo MSC ancestors in a wide range of tissues, which contribute to the heterogeneity of the starting material for the expansion of MSCs. This variability in the MSC culture-initiating cell population, together with the different types of enrichment/isolation and cultivation protocols applied, are hampering progress in the definition of MSC-based therapies. International regulatory statements require a precise risk/benefit analysis, ensuring the safety and efficacy of treatments. GMP validation allows for quality certification, but the prediction of a clinical outcome after MSC-based therapy is correlated not only to the possible morbidity derived by cell production process, but also to the biology of the MSCs themselves, which is highly sensible to unpredictable fluctuation of isolating and culture conditions. Risk exposure and efficacy of MSC-based therapies should be evaluated by pre-clinical studies, but the batch-to-batch variability of the final medicinal product could significantly limit the predictability of these studies. The future success of MSC-based therapies could lie not only in rational optimization of therapeutic strategies, but also in a stochastic approach during the assessment of benefit and risk factors.

EGF-induced adipose tissue mesothelial cells undergo functional vascular smooth muscle differentiation

Recent studies suggested that the post-natal mesothelium retain differentiative potential of the embryonic mesothelium, which generates fibroblasts and vascular smooth muscle cells (VSMCs), in developing coelomic organs via epithelial-to-mesenchymal transition (EMT). Whether adult mesothelial cells (MCs) are able to give rise to functional VSMCs in vitro and which are the factors and mechanisms directing this process remain largely unknown. Here, we isolated adipose tissue MCs (ATMCs) from adult mice, and demonstrated that ATMCs cultured in a serum-containing media supplemented with epidermal growth factor (EGF) efficiently increased both their proliferation and EMT above levels found in only serum-containing media cultures. EGF-induced ATMCs gained phosphorylation of the EGF receptor and activated simultaneously ILK/Erk1/2, PI3K/Akt and Smad2/3-dependent pathways. Sequential subculture onto collagen-I surface efficiently improved their vasculogenic EMT towards cells featuring VSMCs (α-SMA, calponin, caldesmon, SM22α, desmin, SM-MHC, smoothelin-B and PDGFR-β) that could actively contract in response to receptor and non-receptor-mediated vasoactive agonists. Overall, our results indentify EGF signalling as a robust vasculogenic inductive pathway for ATMCs, leading to their transdifferentiation into functional VSMC-like cells.

Enhancing effect of glucose microspheres in the viability of human mesenchymal stem cell suspensions for clinical administration

PURPOSE

A critical limiting factor of cell therapy is the short life of the stem cells. In this study, glucose containing alginate microspheres were developed and characterized to provide a sustained release system prolonging the viability of human mesenchymal stem cells (hMSCs) in a suspension for clinical application.

METHODS

The glucose microspheres were satisfactorily elaborated with alginate by emulsification/internal gelation method. Particle size was evaluated by light diffraction and optical microscopy. Shape and surface texture by scanning electron microscopy (SEM). Zeta potential, infrared spectra and release studies were also conducted. Also, rheological properties and stability of hMSCs suspensions with microspheres were tested. The viability of hMSCs was determined by trypan blue dye exclusion staining.

RESULTS

Microspheres of 86.62 μm, spherical shaped and -32.54 mV zeta potential with excellent stability, good encapsulation efficiency and providing an exponential release of glucose were obtained. hMSCs had better survival rate when they were packed with glucose microspheres. Microspheres maintained the aseptic conditions of the cell suspension without rheological, morphological or immunophenotypic disturbances on hMSCs.

CONCLUSIONS

Developed microspheres were able to enhance the functionality of hMSC suspension. This strategy could be broadly applied to various therapeutic approaches in which prolonged viability of cells is necessary.

Standard requirement of a microbiological quality control program for the manufacture of human mesenchymal stem cells for clinical use

The manufacturing of human mesenchymal stem cells (hMSCs) as cell-based products for clinical use should be performed with appropriate controls that ensure its safety and quality. The use of hMSCs in cell therapy has increased considerably in the past few years. In line with this, the assessment and management of contamination risks by microbial agents that could affect the quality of cells and the safety of patients have to be considered. It is necessary to implant a quality control program (QCP) covering the entire procedure of the ex vivo expansion, from the source of cells, starting materials, and reagents, such as intermediate products, to the final cellular medicine. We defined a QCP to detect microbiological contamination during manufacturing of autologous hMSCs for clinical application. The methods used include sterility test, Gram stain, detection of mycoplasma, endotoxin assay, and microbiological monitoring in process according to the European Pharmacopoeia (Ph. Eur.) and each analytical technique was validated in accordance with three different cell cultures. Results showed no microbiological contamination in any phases of the cultures, meeting all the acceptance criteria for sterility test, detection of mycoplasma and endotoxin, and environmental and staff monitoring. Each analytical technique was validated demonstrating the sensitivity, limit of detection, and robustness of the method. The quality and safety of MSCs must be controlled to ensure their final use in patients. The evaluation of the proposed QCP revealed satisfactory results in order to standardize this procedure for clinical use of cells.