Islets Transplantation at a Crossroads - Need for Urgent Regulatory Update in the United States: Perspective Presented During the Scientific Sessions 2021 at the American Diabetes Association Congress.

Clinical islet allotransplantation has been successfully regulated as tissue/organ for transplantation in number of countries and is recognized as a safe and efficacious therapy for selected patients with type 1 diabetes mellitus. However, in the United States, the FDA considers pancreatic islets as a biologic drug, and islet transplantation has not yet shifted from the experimental to the clinical arena for last 20 years. In order to transplant islets, the FDA requires a valid Biological License Application (BLA) in place. The BLA process is costly and lengthy. However, despite the application of drug manufacturing technology and regulations, the final islet product sterility and potency cannot be confirmed, even when islets meet all the predetermined release criteria. Therefore, further regulation of islets as drugs is obsolete and will continue to hinder clinical application of islet transplantation in the US. The Organ Procurement and Transplantation Network together with the United Network for Organ Sharing have developed separately from the FDA and BLA regulatory framework for human organs under the Human Resources & Services Administration to assure safety and efficacy of transplantation. Based on similar biologic characteristics of islets and human organs, we propose inclusion of islets into the existing regulatory framework for organs for transplantation, along with continued FDA oversight for islet processing, as it is for other cell/tissue products exempt from BLA. This approach would reassure islet quality, efficacy and access for Americans with diabetes to this effective procedure.

Regulatory considerations of delayed autologous islet infusion in a 4-year-old child undergoing total pancreatectomy for chronic pancreatitis.

In patients undergoing total pancreatectomy for chronic pancreatitis, isolation, and infusion of autologous islets must comply with Good Manufacturing Practices standards established by the Food and Drug Administration (FDA) but does not standardly require an Investigational New Drug (IND) status. We report a case of a 4-year-old child with severe hereditary pancreatitis who developed clinical sepsis during total pancreatectomy (TP) surgery; subsequent pancreas, islet, and blood cultures were positive for Enterococcus. Because of clinical deterioration, planned islet infusion was aborted and islets were kept viable in a culture period while the patient was stabilized. Two days later, 38 000 islet equivalents (IEQ, 2808 IEQ/kg) were infused in a second procedure. Because maintaining the islets in culture met the FDA standard for "more than minimal" tissue manipulation, an emergency IND was obtained from the FDA to permit delayed infusion. The patient tolerated islet infusion well, and subsequently has partial islet graft function with normal glucoses and minimal insulin needs. This case highlights the possibility to delay islet infusion in an emergency, the potential for success with few islets in a young child, and the need to consider regulatory complexities of islet transplant in this situation.

Promising potentials of Tibetan macaques in xenotransplantation.

Organ transplantation is a crucial medical procedure, as it is often the only treatment for patients suffering from end-stage organ failure. Unfortunately, the shortage of donor organs limits the number of patients whose lives can be saved. Carrying out research on xenotransplantation with the aim of eventually replacing human organ transplants with those of animals is very promising, as it could effectively bridge the shortfall in donor organs. Thanks to the success of cloned pigs and to the emergence of gene-editing techniques, genetically modified pigs have come to be considered ideal animal donors for human xenotransplantation and have been widely used in basic research. Such research focuses on pig-to-nonhuman primates transplantation, as the recipients are suitable for preclinical studies because both their genes and organ sizes are similar to those of humans. Chinese transplantation scientists have carried out several experiments on Tibetan macaques, including successful preclinical transplants of material from genetically modified pigs, as well as research on such topics as intraocular pressure, Parkinson's disease, advanced cancer, islet transplantation, and liver transplantation. This article reviews basic and applied research on Tibetan macaques in xenotransplantation, as well as the issues of immune rejection and ethical concerns. We aim to demonstrate the various advantages of Tibetan macaques as transplant recipients compared to other nonhuman primate species and to provide a perspective for the future establishment of Tibetan macaques as principal recipients in preclinical studies of xenotransplantation.

Update regarding xenotransplantation in Japan.

To overcome the donor shortage, a promising solution could be xenotransplantation. The pig is generally considered the most suitable donor species for xenotransplantation. A clinical xenotransplantation has not been conducted in Japan. However, many progresses have recently been made in this field. Japan has regulations for conducting cell xenotransplantation and guidelines to prevent zoonosis. Most Japanese patients and their family members have a positive opinion about islet xenotransplantation. A grant for clinical islet xenotransplantation research and development has been approved, and germ-free pigs have been developed. Further research may bring the successful application of xenotransplantation closer to reality.

First update of the International Xenotransplantation Association consensus statement on conditions for undertaking clinical trials of porcine islet products in type 1 diabetes--Executive summary.

The International Xenotransplantation Association has updated its original "Consensus Statement on Conditions for Undertaking Clinical Trials of Porcine Islet Products in Type 1 Diabetes," which was published in Xenotransplantation in 2009. This update is timely and important in light of scientific progress and changes in the regulatory framework pertinent to islet xenotransplantation. Except for the chapter on "informed consent," which has remained relevant in its 2009 version, all other chapters included in the initial consensus statement have been revised for inclusion in this update. These chapters will not provide complete revisions of the original chapters; rather, they restate the key points made in 2009, emphasize new and under-appreciated topics not fully addressed in 2009, suggest relevant revisions, and communicate opinions that complement the consensus opinion. Chapter 1 provides an update on national regulatory frameworks addressing xenotransplantation. Chapter 2 a, previously Chapter 2, suggests several important revisions regarding the generation of suitable source pigs from the perspective of the prevention of xenozoonoses. The newly added Chapter 2b discusses conditions for the use of genetically modified source pigs in clinical islet xenotransplantation. Chapter 3 reviews porcine islet product manufacturing and release testing. Chapter 4 revisits the critically important topic of preclinical efficacy and safety data required to justify a clinical trial. The main achievements in the field of transmission of all porcine microorganisms, the rationale for more proportionate recipient monitoring, and response plans are reviewed in Chapter 5. Patient selection criteria and circumstances where trials of islet xenotransplantation would be both medically and ethically justified are examined in Chapter 6 in the context of recent advances in available and emerging alternative therapies for serious and potentially life-threatening complications of diabetes. It is hoped that this first update of the International Xenotransplantation Association porcine islet transplant consensus statement will assist the islet xenotransplant scientific community, sponsors, regulators, and other stakeholders actively involved in the clinical translation of islet xenotransplantation.

First update of the International Xenotransplantation Association consensus statement on conditions for undertaking clinical trials of porcine islet products in type 1 diabetes--Chapter 3: Porcine islet product manufacturing and release testing criteria.

In the 2009 IXA consensus, the requirements for the quality and control of manufacturing of porcine islet products were based on the U.S. regulatory framework where the porcine islet products fall within the definition of somatic cell therapy under the statutory authority of the U.S. Food and Drug Administration (FDA). In addition, porcine islet products require pre-market approval as a biologic product under the Public Health Services Act and they meet the definition of a drug under the Federal Food, Drug, and Cosmetic Act (FD&C Act). Thus, they are subject to applicable provisions of the law and as such, control of manufacturing as well as reproducibility and consistency of porcine islet products, safety of porcine islet products, and characterization of porcine islet products must be met before proceeding to clinical trials. In terms of control of manufacturing as well as reproducibility and consistency of porcine islet products, the manufacturing facility must be in compliance with current Good Manufacturing Practices (cGMP) guidelines appropriate for the initiation of Phase 1/2 clinical trials. Sponsors intending to conduct a Phase 1/2 trial of islet xenotransplantation products must be able to demonstrate the safety of the product through the establishment of particular quality assurance and quality control procedures. All materials (including animal source and pancreas) used in the manufacturing process of the porcine islet products must be free of adventitious agents. The final porcine islet product must undergo tests for the presence of these adventitious agents including sterility, mycoplasma (if they are cultured), and endotoxin. Assessments of the final product must include the safety specifications mentioned above even if the results are not available until after release as these data would be useful for patient diagnosis and treatment if necessary. In addition, a plan of action must be in place for patient notification and treatment in case the sterility culture results are positive. In terms of the characterization of porcine islet products and product release criteria, the information on the porcine islet products should be acquired from a sample of the final product to be used for transplantation and must include the morphology of the islets, specific identity, purity, viability, and potency of the product. In addition, information on the quantity of the islet products should also be provided in a standardized fashion and this should be in terms of islet equivalents and/or cell numbers. The current consensus was created to provide guidelines that manufacturing facilities may find helpful in the manufacture of and the release criteria for porcine islet products including encapsulated islets and combined islet products. Our intent with the above recommendations is to provide a framework for individual porcine islet manufacturing facilities to ensure a high level of safety for the initiation of Phase 1/2 clinical trials on porcine islet xenotransplantation.

First update of the International Xenotransplantation Association consensus statement on conditions for undertaking clinical trials of porcine islet products in type 1 diabetes--Chapter 2b: genetically modified source pigs.

Genetic modification of the source pig offers the opportunity to improve the engraftment and survival of islet xenografts. The type of modification can be tailored to the transplant setting; for example, intraportal islet xenografts have been shown to benefit from the expression of anticoagulant and anti-inflammatory transgenes, whereas cytoprotective transgenes are probably more relevant for encapsulated islets. The rapid development of pig genetic engineering, particularly with the introduction of genome editing techniques such as CRISPR-Cas, has accelerated the generation of new pig lines with multiple modifications. With pre-clinical testing in progress, it is an opportune time to consider any implications of genetic modification for the conditions for undertaking clinical trials. Obviously, the stringent requirements to fulfill designated pathogen-free status that are applied to wild-type pigs will apply equally to genetically modified (GM) source pigs. In addition, it is important from a safety perspective that the genetic modifications are characterized at the molecular level (e.g., integration site, absence of off-target mutations), the phenotypic level (e.g., durability and stability of transgene expression), and the functional level (e.g., protection of islets in vitro or in vivo, absence of detrimental effects on insulin secretion). The assessment of clinical trial protocols using GM pig islets will need to be performed on a case-by-case basis, taking into account a range of factors including the particular genetic modification(s) and the site and method of delivery.

Human pancreatic islet transplantation: an update and description of the establishment of a pancreatic islet isolation laboratory.

Type 1 diabetes mellitus (T1DM) is associated with chronic complications that lead to high morbidity and mortality rates in young adults of productive age. Intensive insulin therapy has been able to reduce the likelihood of the development of chronic diabetes complications. However, this treatment is still associated with an increased incidence of hypoglycemia. In patients with "brittle T1DM", who have severe hypoglycemia without adrenergic symptoms (hypoglycemia unawareness), islet transplantation may be a therapeutic option to restore both insulin secretion and hypoglycemic perception. The Edmonton group demonstrated that most patients who received islet infusions from more than one donor and were treated with steroid-free immunosuppressive drugs displayed a considerable decline in the initial insulin independence rates at eight years following the transplantation, but showed permanent C-peptide secretion, which facilitated glycemic control and protected patients against hypoglycemic episodes. Recently, data published by the Collaborative Islet Transplant Registry (CITR) has revealed that approximately 50% of the patients who undergo islet transplantation are insulin independent after a 3-year follow-up. Therefore, islet transplantation is able to successfully decrease plasma glucose and HbA1c levels, the occurrence of severe hypoglycemia, and improve patient quality of life. The goal of this paper was to review the human islet isolation and transplantation processes, and to describe the establishment of a human islet isolation laboratory at the Endocrine Division of the Hospital de Clínicas de Porto Alegre - Rio Grande do Sul, Brazil.

Human pancreatic islet transplantation: an update and description of the establishment of a pancreatic islet isolation laboratory

Type 1 diabetes mellitus (T1DM) is associated with chronic complications that lead to high morbidity and mortality rates in young adults of productive age. Intensive insulin therapy has been able to reduce the likelihood of the development of chronic diabetes complications. However, this treatment is still associated with an increased incidence of hypoglycemia. In patients with “brittle T1DM”, who have severe hypoglycemia without adrenergic symptoms (hypoglycemia unawareness), islet transplantation may be a therapeutic option to restore both insulin secretion and hypoglycemic perception. The Edmonton group demonstrated that most patients who received islet infusions from more than one donor and were treated with steroid-free immunosuppressive drugs displayed a considerable decline in the initial insulin independence rates at eight years following the transplantation, but showed permanent C-peptide secretion, which facilitated glycemic control and protected patients against hypoglycemic episodes. Recently, data published by the Collaborative Islet Transplant Registry (CITR) has revealed that approximately 50% of the patients who undergo islet transplantation are insulin independent after a 3-year follow-up. Therefore, islet transplantation is able to successfully decrease plasma glucose and HbA1c levels, the occurrence of severe hypoglycemia, and improve patient quality of life. The goal of this paper was to review the human islet isolation and transplantation processes, and to describe the establishment of a human islet isolation laboratory at the Endocrine Division of the Hospital de Clínicas de Porto Alegre – Rio Grande do Sul, Brazil.

Regulation of xenogeneic porcine pancreatic islets.

The use of xenogeneic porcine pancreatic islets has been shown to be a potentially promising alternative to using human allogeneic islets to treat insulin-dependent type 1 diabetes (T1D). This article provides an overview of the existing FDA regulatory framework that would be applied to the regulation of clinical trials utilizing xenogeneic porcine pancreatic islets to treat T1D.

The International Xenotransplantation Association consensus statement on conditions for undertaking clinical trials of porcine islet products in type 1 diabetes--chapter 1: Key ethical requirements and progress toward the definition of an international regulatory framework.

The outstanding results recently obtained in islet xenotransplantation suggest that porcine islet clinical trials may soon be scientifically appropriate. Before the initiation of such clinical studies, however, it is essential that a series of key ethical and regulatory conditions are satisfied. As far as ethics is concerned, the fundamental requirements have been previously reported in a position paper of the Ethics Committee of the International Xenotransplantation Association. These include aspects related to the selection of adequately informed, appropriate recipients; animal breeding and welfare; safety issues and the need for a favorable risk/benefit assessment based on strong efficacy data in relevant xenotransplantation studies in the primate. As most diabetic patients are not at risk of short-term mortality without islet transplantation, only a small subset of patients could currently be considered for any type of islet transplant. However, there are potential advantages to xenotransplantation that could result in a favorable benefit-over-harm determination for islet xenotransplantation in this subpopulation and ultimately in a broader population of diabetic patients. With regard to regulatory aspects, the key concepts underlying the development of the regulatory models in existence in the United States, Europe and New Zealand are discussed. Each of these models provides an example of a well-defined regulatory approach to ensure the initiation of well-regulated and ethically acceptable clinical islet xenotransplantation trials. At this stage, it becomes apparent that only a well-coordinated international effort such as that initiated by the World Health Organization, aimed at harmonizing xenotransplantation procedures according to the highest ethical and regulatory standards on a global scale, will enable the initiation of clinical xenotransplantation trials under the best auspices for its success and minimize any risk of failure.

The International Xenotransplantation Association consensus statement on conditions for undertaking clinical trials of porcine islet products in type 1 diabetes--chapter 7: Informed consent and xenotransplantation clinical trials.

This essay explores the meaning and implications of informed consent in xenotransplantation clinical trials from both ethically justifiable and international perspectives. In international and national codes and guidelines involving human subject research and in the laws of many nations, the informed consent of research subjects is obligatory. Its moral foundations include and also extend beyond respect for individual persons as autonomous agents in Western nations. Axioms regarding the value of human life and duties to protect innocent and vulnerable persons from harm, duress, and deceit underlie Western individualism and are broadly shared in many non-Western cultures. Accents on family and/or community consent in China and other nations are compatible with individual consent as long as family and community consent supplement, rather than replace, individual consent. Reflecting its moral foundations, informed consent in medical research is rightly characterized as "voluntary" or "freely given" informed consent because it encompasses researchers' disclosure and subjects' comprehension of all the relevant information about the protocol that reasonable persons would want to know in order to freely and affirmatively enroll in the research. The interplay between these conceptual foundations of informed consent and the realities of xenotransplantation research defines what the nature and functions of consent should be in xenotransplantation clinical trials. Because these trials involve a complex body of medical information, numerous procedures, numerous risks (associated with failure rates, immunosuppression, xenogeneic infections, and so on) and the subject's obligation to abide by extensive national and international precautionary guidelines, informed consent should be enacted as an organized, sequential, thoughtfully paced, jargon-free process of communication. The features and functions of consent forms or consent documents should accord with this process. Rather than being virtually equated with informed consent, consent documents should be utilized as templates of relevant, essential, and understandable information that contribute to comprehension and voluntary enrollment. In xenotransplantation clinical research, the consenting process must cover a large number of topics, including treatment choices, participation information, study procedures, information about risks associated with immunosuppression, xenogeneic infections, discomforts, and other matters. In addition, due to infectious risks, subjects are obliged to 10 post-protocol responsibilities. Two of the three unique moral issues regarding informed consent in xenotransplantation trials involve what to do to minimize post-protocol infectious risks and what to do about international and national guidelines that affirm the subject's right to withdraw from participation in medical research at any time. The third moral issue centers on issues involving the enrollment of children and mentally incapacitated adults. The other chapters in this consensus statement demonstrate that, morally and logically, favorable harm-benefit determinations precede considerations of informed consent. When these harm-benefit assessments are favorable enough to warrant the onset of clinical trials, informed consent emerges as a pivotal moral precondition for these trials.

Regulatory issues in xenotransplantation: recent developments.

PURPOSE OF REVIEW: This article reviews recent literature on regulatory issues of xenotransplantation, focusing primarily on current progress with transplantation of pancreatic islets for diabetic patients. The need for a global system that connects the national and international regulatory levels within a coherent framework is emphasized. RECENT FINDINGS: Recent progress in preclinical xenotransplantation of pancreatic islets has enhanced the hopes of providing patients with safe and effective treatments from animal cells and tissues in the near future. At the same time the increasing number of clinical trials proposed and sometimes authorized calls for attention from regulatory authorities. SUMMARY: Although the main regulatory aspects of xenotransplantation have been identified since the early 1990s, regulatory problems connected to the promising scientific data published in the field of pancreatic islets still require attention. In fact most normative issues, such as criteria for patients' enrollment in clinical trials and the management of safety measures have been primarily explored in relation to solid organ transplantation. Also the issue of animal rights has become more compelling in relation to the treatment of nonhuman primates in preclinical trials. In these rapidly evolving conditions the establishment of agreed guidelines at both the national and international levels remains the most urgent goal to be achieved.

Organ procurement organization compliance with 21 CFR 1271: a challenge for allogeneic pancreatic islet cell transplantation programs.

In order to protect tissue recipients, the Food and Drug Administration drafted Title 21, Section 1271 of the Code of Federal Regulations 1271 (21 CFR 1271) to address infectious disease risk. These regulations apply to tissues but not vascularized organs. Pancreatic islet cells are regulated under 21 CFR 1271. These regulations require qualification of suppliers of critical materials and services with regard to 21 CFR 1271 compliance. As part of supplier qualification, all organ procurement organizations (OPOs) in the United States were sent a questionnaire covering the key components of these regulations. Of the 57 OPOs, 29 (51%) were in compliance based upon survey results. Twelve (21%) were not compliant in one or more areas. All indicated plans to become compliant. The remaining 15 (27%) either failed or refused to complete the survey, some indicating 21 CFR 1271 did not apply to OPOs. Using 2006 data, OPOs compliant with 21 CFR 1271 recovered 50% of the organs procured in the United States. These findings represent a challenge for allogeneic islet cell transplant programs whose raw material must comply with 21 CFR 1271. OPOs should work toward understanding and complying with 21 CFR 1271. Regulatory agencies should work toward enhancing safety of the pancreas supply by facilitating compliance through harmonization of requirements.

Regulatory challenges in manufacturing of pancreatic islets.

At the present time, transplantation of pancreatic islet cells is considered an experimental therapy for a selected cohort of patients with type 1 diabetes, and is conducted under an Investigational New Drug (IND) application. Encouraging results of the Edmonton Protocol published in the year 2000 sparked a renewed interest in clinical transplantation of allogeneic islets, triggering a large number of IND applications for phase I clinical trials. Promising results reported by a number of centers since then prompted the Food and Drug Administration (FDA) to consider the possibility of licensing allogeneic islets as a therapeutic treatment for patients with type 1 diabetes. However, prior to licensure, issues such as safety, purity, efficacy, and potency of the islet product must be addressed. This is complicated by the intricate nature of pancreatic islets and limited characterization prior to transplantation. In this context, control of the manufacturing process plays a critical role in the definition of the final product. Despite significant progress made in standardization of the donor organ preservation methods, reagents used, and characterization assays performed to qualify an islet cell product, control of the isolation process remains a challenge. Within the scope of the FDA regulations, islet cells meet the definition of a biologic product, somatic cell therapy, and a drug. In addition, AABB standards that address cellular therapy products apply to manufacturing facilities accredited by this organization. Control of the source material, isolation process, and final product are critical issues that must be addressed in the context of FDA and other relevant regulations applicable to islet cell products.

Estado actual del trasplante de islotes pancreáticos / Current status of islet transplantation

El trasplante de islotes pancreáticos mejora día a día sus resultados clínicos gracias a numerosas mejoras en el proceso desarrolladas en los últimos años. Tanto los nuevos protocolos de inmunosupresión como la selección de los donantes y receptores, así como un especial cuidado en la obtención, preservación y procesamiento de los páncreas, han hecho posible conseguir controles glucémicos prolongados. Uno de los objetivos principales de esta revisión es presentar la evolución de los resultados en humanos a medida que estos cambios han ido introduciéndose. Asimismo, se revisa el empleo de nuevas fuentes de islotes, como son el donante vivo y el donante a corazón parado, junto con los nuevos hallazgos en el conocimiento de los mecanismos de rechazo y las nuevas opciones terapéuticas desarrolladas para prevenirlo (AU)

Due to the numerous advances in islet transplantation in the last few years, clinical outcomes following this procedure are continually improving. Novel immunosuppression protocols, improved donor and recipient selection, and careful attention to the process of organ extraction, preservation and islet isolation have contributed to long-term success. The present article reviews the results of clinical islet transplantation and their relationship with the different advances introduced. The use of new islet sources such as living and non-heart-beating donors, as well as recent advances in our knowledge of the mechanisms of rejection and its prevention, are also reviewed (AU)

Update on regulatory issues in pancreatic islet transplantation.

Over the past 12 years, the US Food and Drug Administration (FDA) has reviewed more than 40 investigational new drug applications for the use of allogeneic pancreatic islets to treat type 1 diabetes mellitus. Recent advances in islet cell isolation, transplantation, and immunosuppressive maintenance have led to multiple centers reporting promising results in the treatment of type 1 diabetes with allogeneic islet cells. The FDA held an advisory committee meeting on October 9-10, 2003, to explore the potential for licensing allogeneic islets as a therapy for severe type 1 diabetes. This article highlights the manufacturing challenges, discussed by the FDA advisory committee, that remain to be resolved before allogeneic islets can be approved for treatment of type 1 diabetes. This article also briefly addresses the challenges facing the clinical trial design of studies that could be used to support licensure.

Selected Food and Drug Administration review issues for regulation of allogeneic islets of langerhans as somatic cell therapy.

The Food and Drug Administration has seen a significant increase in investigational new drug (IND) applications for the use of allogeneic islets of Langerhans to treat type 1 diabetes mellitus. The current regulatory framework for clinical use of allogeneic islets of Langerhans is described. In addition, expectations and considerations for information to be included in the manufacturing, preclinical, and clinical sections of an IND for allogeneic islets of Langerhans to treat type 1 diabetes mellitus are discussed.