F04.41 - Classification and Terminology for TEMPs

SIGNIFICANCE AND USE
4.1 This guide provides definitions and a classification for CTPs, as well as definitions related to skin tissue, skin wounds and ulcers, wound healing physiology, wound covers, and related medical and surgical procedures. This guide is not intended to prescribe or limit the clinical uses of these products.  
4.2 One objective of the current guide is to include the wide range of CTPs for which there is a rationale for benefit beyond that achievable with conventional wound coverings. Whether an individual CTP is capable of promoting wound healing must be determined by adequate evidence and is beyond the scope of this standard. Given that some of the materials used in dressings and skin substitutes (defined in Guide F2311) are the same as those used in CTPs, there has been confusion as to how to classify these products.  
4.3 This guide is distinguished from Guide F2311, which defines terminology and provides classification by clinical use for products that can be substituted for tissue grafts of human or animal tissue in medical and surgical therapies of skin lesions. In contrast, this guide defines terminology for description of CTPs for skin wounds; CTPs are defined primarily by their composition. Neither guide establishes a correspondence between device structure and clinical function.
SCOPE
1.1 This guide defines terminology for description of cellular and/or tissue-based products (CTPs) for skin wounds. CTPs are TEMPs (tissue-engineered medical products) that are primarily defined by their composition and comprise viable and/or nonviable human or animal cells, viable and/or nonviable tissues, and may include extracellular matrix components. CTPs may additionally include synthetic components.  
1.2 This guide also describes categories and terminology for CTPs based on their composition. This systematic categorization is not intended to be prescriptive for product labeling, and it describes only the most salient characteristics of these products; the actual biological and clinical functions can depend on characteristics not recognized in the categorization and it should be understood that two products that can be described identically by the categorization should not be presumed to be identical or have the same clinical utility.  
1.3 This guide defines CTP-related terminology in the context of skin wounds. However, this guide does not provide a correspondence between the CTP composition and its clinical use(s). More than one product may be suitable for each clinical use, and one product may have more than one clinical use.  
1.4 This guide does not purport to address safety concerns with the use of CTPs. It is the responsibility of the user of this standard to establish appropriate safety and health practices involved in the development of said products in accordance with applicable regulatory guidance documents and in implementing this guide to evaluate the cellular and/or tissue-based products for wounds.  
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

SIGNIFICANCE AND USE
4.1 This classification outlines aspects of TEMPs which includes their individual components.  
4.2 The categories outlined in this classification are intended to list, identify, and group the areas pertinent to tissue-engineered medical products. This classification will be used by the Tissue-Engineered Medical Products subcommittees for the organization of the development of standards for the field of tissue engineering, TEMPs, and protocols for their use. The development of products from the new tissue engineering technologies necessitates creation and implementation of new standards (1).5  
4.3 Since interactions may occur among the components used in TEMPs, new standard descriptions, test methods, and practices are needed to aid the evaluation of these interactions. The degree of overall risk for any given TEMP is reflected by the number and types of tests required to demonstrate product safety and efficacy.
SCOPE
1.1 This classification outlines the aspects of tissue-engineered medical products that will be developed as standards. This classification excludes traditional transplantation of organs and tissues as well as transplantation of living cells alone as cellular therapies.  
1.2 This classification does not apply to any medical products of human origin regulated by the U.S. Food and Drug Administration under 21 CFR Parts 16 and 1270 and 21 CFR Parts 207, 807, and 1271.  
1.3 This standard does not purport to address specific components covered in other standards. Any safety areas associated with the medical product's use will not be addressed in this standard. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

SIGNIFICANCE AND USE
3.1 The need for standards regarding TEMPs has also prompted a need for definitions. This terminology sets forth definitions of the most commonly used terms and specifies the relationship among the sciences and components applied in tissue engineering to develop TEMPs. Use of these terms and an understanding of these relationships will unify the ASTM TEMPs standards with a common language such that the users of these standards can understand and interpret the standards more precisely. Terms specific to a TEMP standard will also be defined within the respective standard as appropriate.  
3.2 Defining Terms—Terms are defined with a broad scope to encompass these new products known as TEMPs. For instance, the definition for somatic cell therapy as stated in the “Guidance for Human Somatic Cell Therapy and Gene Therapy” (1)3 is recognized in this terminology. However, for the purposes of TEMPs that contain cells, we have added the definition of “cell” which is much broader and not limited to the use of living cells.  
3.3 Clinical Effects of TEMPs—The users of this terminology should note that terms used regarding the clinical effects of TEMPs, for instance, “modify or modification” of the patient's condition, may also be interpreted to “enhance, augment, transform, alter, improve, or supplement.” Similarly, “repair” may also serve to mean “restore.”  
3.4 The diagram in Fig. 1 shows the relationships of components of TEMPs and of the fields of science (for example, technologies and principles) used in tissue engineering to create TEMPs. Certain TEMPs may be tissue engineered or produced in vitro by using specific components and sciences to create an off-the-shelf TEMP for the users. Other TEMPs may by design require the users to place the components inside the patient, (that is, in vivo) to rely upon the patient's regenerative potential to achieve the product's primary intended purpose. The expectation of a TEMP used for therapeutic clinical applications is to have ...
SCOPE
1.1 This terminology defines basic terms and presents the relationships of the scientific fields related to Tissue Engineered Medical Products (TEMPs). Committee F04 has defined these terms for the specific purpose of unifying the language used in standards for TEMPs.  
1.2 The terms and relationships defined here are limited to TEMPs. They do not apply to any medical products of human origin regulated by the U.S. Food and Drug Administration under 21 CFR Parts 16 and 1270 and 21 CFR Parts 207, 807, and 1271.  
1.3 The terms and nomenclature presented in this standard are for the specific purposes of unifying the language used in TEMP standards and are not intended for labeling of regulated medical products.  
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

SIGNIFICANCE AND USE
5.1 This guide provides definitions and a classification for CTPs, as well as definitions related to skin tissue, skin wounds and ulcers, wound healing physiology, wound covers, and related medical and surgical procedures. This guide is not intended to prescribe or limit the clinical uses of these products.  
5.2 One objective of the current guide is to include the wide range of CTPs for which there is a rationale for benefit beyond that achievable with conventional wound coverings. Whether an individual CTP is capable of promoting wound healing must be determined by adequate evidence and is beyond the scope of this standard. Given that some of the materials used in dressings and skin substitutes (defined in ASTM Standard F2311) are the same as those used in CTPs, there has been confusion as to how to classify these products.  
5.3 This guide is distinguished from ASTM Standard F2311, which defines terminology and provides classification by clinical use for products that can be substituted for tissue grafts of human or animal tissue in medical and surgical therapies of skin lesions. In contrast, this guide defines terminology for description of CTPs for skin wounds; CTPs are defined primarily by their composition. Neither guide establishes a correspondence between device structure and clinical function.
SCOPE
1.1 This guide defines terminology for description of cellular and/or tissue-based products (CTPs) for skin wounds. CTPs are defined primarily by their composition and comprise cells and/or the extracellular components of tissue. CTPs may contain cells (viable or nonviable), tissues, proteins, and other materials for which there is a rationale for benefit beyond that achievable with conventional wound coverings. CTPs may additionally include synthetic components. Whether an individual CTP is capable of promoting wound healing must be determined by adequate evidence and is beyond the scope of this standard.  
1.2 This guide also describes a classification and nomenclature for CTPs based on their composition. This systematic nomenclature is not intended to be prescriptive for product labeling, and it describes only the most salient characteristics of these products; the actual biological and clinical functions can depend on characteristics not recognized in the nomenclature, and it should be understood that two products that can be described identically by the nomenclature should not be presumed to be identical or have the same clinical utility.  
1.3 This guide defines CTP-related terminology in the context of skin wounds. However, this guide does not provide a correspondence between the CTP composition and its clinical use(s). More than one product may be suitable for each clinical use, and one product may have more than one clinical use.  
1.4 This standard does not purport to address safety concerns with the use of CTPs. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SIGNIFICANCE AND USE
4.1 This classification outlines aspects of TEMPs which includes their individual components.  
4.2 The categories outlined in this classification are intended to list, identify, and group the areas pertinent to Tissue Engineered Medical Products. This classification will be used by the Tissue Engineered Medical Products subcommittees for the organization of the development of standards for the field of tissue engineering, TEMPs, and protocols for their use. The development of products from the new tissue engineering technologies necessitates creation and implementation of new standards (1).5  
4.3 Since interactions may occur among the components used in TEMPs, new standard descriptions, test methods, and practices are needed to aid the evaluation of these interactions. The degree of overall risk for any given TEMP is reflected by the number and types of tests required to demonstrate product safety and efficacy.
SCOPE
1.1 This classification outlines the aspects of tissue engineered medical products that will be developed as standards. This classification excludes traditional transplantation of organs and tissues as well as transplantation of living cells alone as cellular therapies.  
1.2 This classification does not apply to any medical products of human origin regulated by the U.S. Food and Drug Administration under 21 CFR Parts 16 and 1270 and 21 CFR Parts 207, 807, and 1271.  
1.3 This standard does not purport to address specific components coverd in other standards. Any safety areas associated with the medical product's use will not be addressed in this standard. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory requirements prior to use.

SIGNIFICANCE AND USE
This classification outlines aspects of TEMPs which includes their individual components.
The categories outlined in this classification are intended to list, identify, and group the areas pertinent to Tissue Engineered Medical Products. This classification will be used by the Tissue Engineered Medical Products subcommittees for the organization of the development of standards for the field of tissue engineering, TEMPs, and protocols for their use. The development of products from the new tissue engineering technologies necessitates creation and implementation of new standards (1).5  
Since interactions may occur among the components used in TEMPs, new standard descriptions, test methods, and practices are needed to aid the evaluation of these interactions. The degree of overall risk for any given TEMP is reflected by the number and types of tests required to demonstrate product safety and efficacy.
SCOPE
1.1 This classification outlines the aspects of tissue engineered medical products that will be developed as standards. This classification excludes traditional transplantation of organs and tissues as well as transplantation of living cells alone as cellular therapies.
1.2 This classification does not apply to any medical products of human origin regulated by the U.S. Food and Drug Administration under 21 CFR Parts 16 and 1270 and 21 CFR Parts 207, 807, and 1271.
1.3 This standard does not purport to address specific components coverd in other standards. Any safety areas associated with the medical product's use will not be addressed in this standard. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory requirements prior to use.
WITHDRAWN RATIONALE
This classification outlines the aspects of tissue engineered medical products that will be developed as standards. This classification excludes traditional transplantation of organs and tissues as well as transplantation of living cells alone as cellular therapies.
Formerly under the jurisdiction of Committee F04 on Medical and Surgical Materials and Devices, this classification was withdrawn in January 2013 in accordance with section 10.5.3.1 of the Regulations Governing ASTM Technical Committees, which requires that standards shall be updated by the end of the eighth year since the last approval date.

SIGNIFICANCE AND USE
The need for standards regarding TEMPs has also prompted a need for definitions. This terminology sets forth definitions of the most commonly used terms and specifies the relationship among the sciences and components applied in tissue engineering to develop TEMPs. Use of these terms and an understanding of these relationships will unify the ASTM TEMPs standards with a common language such that the users of these standards can understand and interpret the standards more precisely. Terms specific to a TEMP standard will also be defined within the respective standard as appropriate.
Defining Terms—Terms are defined with a broad scope to encompass these new products known as TEMPs. For instance, the definition for somatic cell therapy as stated in the “Guidance for Human Somatic Cell Therapy and Gene Therapy” (4) is recognized in this terminology. However, for the purposes of TEMPs that contain cells, we have added the definition of “cell” which is much broader and not limited to the use of living cells.
Clinical Effects of TEMPs—The users of this terminology should note that terms used regarding the clinical effects of TEMPs, for instance, “modify or modification” of the patient's condition, may also be interpreted to “enhance, augment, transform, alter, improve, or supplement.” Similarly, “repair” may also serve to mean “restore.”
SCOPE
1.1 This terminology defines basic terms and presents the relationships of the scientific fields related to Tissue Engineered Medical Products (TEMPs). Committee F04 has defined these terms for the specific purpose of unifying the language used in standards for TEMPs.
1.2 The terms and relationships defined here are limited to TEMPs. They do not apply to any medical products of human origin regulated by the U.S. Food and Drug Administration under 21 CFR Parts 16 and 1270 and 21 CFR Parts 207, 807, and 1271.
1.3 The terms and nomenclature presented in this standard are for the specific purposes of unifying the language used in TEMP standards and are not intended for labeling of regulated medical products.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SIGNIFICANCE AND USE
The need for standards regarding TEMPs has also prompted a need for definitions. This terminology sets forth definitions of the most commonly used terms and specifies the relationship among the sciences and components applied in tissue engineering to develop TEMPs. Use of these terms and an understanding of these relationships will unify the ASTM TEMPs standards with a common language such that the users of these standards can understand and interpret the standards more precisely. Terms specific to a TEMP standard will also be defined within the respective standard as appropriate.
Defining Terms—Terms are defined with a broad scope to encompass these new products known as TEMPs. For instance, the definition for somatic cell therapy as stated in the “Guidance for Human Somatic Cell Therapy and Gene Therapy” (4) is recognized in this terminology. However, for the purposes of TEMPs that contain cells, we have added the definition of “cell” which is much broader and not limited to the use of living cells.
Clinical Effects of TEMPs—The users of this terminology should note that terms used regarding the clinical effects of TEMPs, for instance, “modify or modification” of the patient's condition, may also be interpreted to “enhance, augment, transform, alter, improve, or supplement.” Similarly, “repair” may also serve to mean “restore.”
The diagram in Fig. 1 shows the relationships of components of TEMPs and of the fields of science (for example, technologies and principles) used in tissue engineering to create TEMPs. Certain TEMPs may be tissue engineered or produced in vitro by using specific components and sciences to create an off-the-shelf TEMP for the users. Other TEMPs may by design require the users to place the components inside the patient, (that is, in vivo) to rely upon the patient's regenerative potential to achieve the product's primary intended purpose. The expectation of a TEMP used for therapeutic clinical applications is to have a therapeutic effect...
SCOPE
1.1 This terminology defines basic terms and presents the relationships of the scientific fields related to Tissue Engineered Medical Products (TEMPs). Committee F04 has defined these terms for the specific purpose of unifying the language used in standards for TEMPs.
1.2 The terms and relationships defined here are limited to TEMPs. They do not apply to any medical products of human origin regulated by the U.S. Food and Drug Administration under 21 CFR Parts 16 and 1270 and 21 CFR Parts 207, 807, and 1271.
1.3 The terms and nomenclature presented in this standard are for the specific purposes of unifying the language used in TEMP standards and are not intended for labeling of regulated medical products.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SIGNIFICANCE AND USE
This guide is intended to provide the foundation of standards for clinical assessment, clinical performance, and preclinical assessment of substitutes for skin grafts.
This guide is intended to aid accurate claims and labeling for the clinical utilities of substitutes for skin grafts in regulatory reviews.
In this guide, “replacement” and “substitute” have different meanings, although they can be used synonymously in ordinary English. “Replacement” is used only as an adjective in the context of “skin replacement surgery,” which is defined in . “Substitute” is used only as a noun in the context of “skin substitute,” which is defined in 2.1.7.11.
SCOPE
1.1 This guide defines terminology and provides a system of classification for products that can be substituted for human or animal skin grafts (or grafts of the dermal or epidermal component tissues of skin) in medical and surgical therapies. This guide is intended to include (or be expandable to) possible future tissue engineered skin technology that could provide novel or superior therapeutic properties to those of natural skin grafts.
1.2 As much as possible, terminology is based on medical dictionary definitions.
1.3 Substitutes for skin grafts are classified by clinical utility only; the classification is independent of the technology used to make a skin substitute, its components, or whether the sources of components include human or animal tissue or other biological or non-biological materials.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory requirements prior to use.

SCOPE
1.1 This terminology defines basic terms and presents the relationships of the scientific fields related to Tissue Engineered Medical Products (TEMPs). Committee F04 has defined these terms for the specific purpose of unifying the language used in standards for TEMPs.
1.2 The terms and relationships defined here are limited to TEMPs. They do not apply to any medical products of human origin regulated by the U.S. Food and Drug Administration under 21 CFR Parts 16 and 1270 and 21 CFR Parts 207, 807, and 1271.
1.3 The terms and nomenclature presented in this standard are for the specific purposes of unifying the language used in TEMP standards and are not intended for labeling of regulated medical products.
This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SCOPE
1.1 This guide defines terminology and provides a system of classification for products that can be substituted for human or animal skin grafts (or grafts of the dermal or epidermal component tissues of skin) in medical and surgical therapies. This guide is intended to include (or be expandable to) possible future tissue engineered skin technology that could provide novel or superior therapeutic properties to those of natural skin grafts.
1.2 As much as possible, terminology is based on medical dictionary definitions.
1.3 Substitutes for skin grafts are classified by clinical utility only; the classification is independent of the technology used to make a skin substitute, its components, or whether the sources of components include human or animal tissue or other biological or non-biological materials.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory requirements prior to use.

SCOPE
1.1 This terminology defines basic terms and presents the relationships of the scientific fields related to Tissue Engineered Medical Products (TEMPs). Committee F04 has defined these terms for the specific purpose of unifying the language used in standards for TEMPs.
1.2 The terms and relationships defined here are limited to TEMPs. They do not apply to any medical products of human origin regulated by the U.S. Food and Drug Administration under 21 CFR Parts 16 and 1270 and 21 CFR Parts 207, 807, and 1271.
1.3 The terms and nomenclature presented in this standard are for the specific purposes of unifying the language used in TEMP standards and are not intended for labeling of regulated medical products.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

SCOPE
1.1 This classification outlines the aspects of tissue engineered medical products that will be developed as standards. This classification excludes traditional transplantation of organs and tissues as well as transplantation of living cells alone as cellular therapies.
1.2 This classification does not apply to any medical products of human origin regulated by the U.S. Food and Drug Administration under 21 CDR Parts 16 and 1270 and 21 CFR Parts 207, 807, and 1271.
1.3 This standard does not purport to address specific components coverd in other standards. Any safety areas associated with the medical product's use will not be addressed in this standard.This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory requirements prior to use.

SIGNIFICANCE AND USE
As much as possible, terminology contained herein is based on medical dictionary definitions.
This guide provides nomenclature and classifications to accurately and unambiguously describe tissue engineered skin substitutes as well as their clinical functions. These classification systems and their nomenclature are not intended to be prescriptive for product labeling or advertising.
In this guide, “replacement” and “substitute” have different meanings, although they can be used synonymously in ordinary English. “Skin substitute,” which is defined in 3.5.2, is a tissue-engineered medical product that a physician or surgeon can use in a medical or surgical procedure. “Skin replacement,” which is defined in 3.7.7, is the therapeutic outcome of successful skin replacement surgery, but this is only one of several clinical uses for skin substitutes.
Skin substitutes are used in different medical settings and by different medical and surgical specialties. In order to help clarify the clinical applications of skin substitutes, a discussion of common medical and surgical procedures that use conventional skin tissue grafts (autograft and fresh or frozen allograft and xenograft) is provided in Section 6. This discussion is intended provide context for understanding the categories of Section 7, which model clinical uses of skin substitutes by comparison with the uses of conventional skin grafts. However, the procedures, circumstances, and surgical intentions in section are not intended to limit the possible uses of skin substitutes, nor is the classification in section intended to limit the uses of skin substitutes to only those uses of conventional skin graft tissues.
SCOPE
1.1 This guide defines terminology and provides classification for products that can be substituted for tissue grafts of human or animal tissue in medical and surgical therapies of skin lesions.
1.2 This guide provides a classification method for skin substitutes by comparing their clinical uses with those of conventional tissue grafts. However, skin substitutes may also have equivalent, superior, or inferior clinical properties in comparison to conventional tissue grafts. Clinical classification is independent of the materials and technology used to make a skin substitute, or whether its components include human or animal tissue or other biological or non-biological materials.
1.3 This guide also describes a nomenclature for systematic description of the technologies and components of skin substitutes that is independent of their clinical utilities. This systematic nomenclature is not intended to be prescriptive for product labeling, and it describes only the most salient characteristics of skin substitutes; the actual biological and clinical functions of skin substitutes can depend on characteristics not recognized in the nomenclature, and it should be understood that two products that can be described identically by the nomenclature should not be presumed to be identical or have the same clinical utility.
1.4 This guide does not provide a correspondence between the skin substitute composition and the clinical classification. Also, more than one product may be suitable for each clinical use, and one product may have more than one clinical use.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
WITHDRAWN RATIONALE
This guide defined terminology and provided classification for products that can be substituted for tissue grafts of human or animal tissue in medical and surgical therapies of skin lesions.
Formerly under the jurisdiction of Committee F04 on Medical and Surgical Materials and Devices, this guide was withdrawn in April 2017 in accordance with section 10.5.3.1 of the Regula...