Despite the progress made in medicine, the interest in unmet medical needs is escalating owing to rare or incurable diseases or ethical issues in clinical trials (Li and Izpisua Belmonte 2019; Wang et al. 2022). To address this issue, innovative solutions such as advanced therapeutic medicinal products are being explored, which organoids included the options (Hanna et al. 2016).

Owing to physiological discrepancies between humans and animals, clinical trials have encountered limitations in complying with conditions and regulations for subjects, conventional animal experiments have been restricted in clinical application (World Medical Association 2013). Organoids are human cell and organ mimics created from cells derived from the human body (Dutta et al. 2017), and once achieve equivalent similarity to the organs, they have the potential to replace conducted preclinical and partially human studies (Kim et al. 2020). Moreover, the organoid techniques for making organoids through the application of induced pluripotent stem cells the unused of embryonic stem cells, a more ethically sound approach in contrast to the potential ethical issues that come with the use of embryonic stem cells (Zheng 2016). Due to these features, organoids have the potential to contribute to medical advances in a variety of areas, including tissue regeneration, precision medicine, and the development of organs for transplantation (Berthiaume et al. 2011; Li et al. 2020).

Recently, preclinical achievements with organoids and some clinical trials have been increasingly reported internationally (Steele et al. 2019; Shi et al. 2020). Despite this, there are currently no global regulations that directly regulate organoids. There are few articles on organoid regulation, and previous studies on organoid regulation are limited to a few countries, making it difficult to grasp the latest global status of organoid regulation (Harris et al. 2022). It is crucial to establish appropriate ethical standards for organoid research, anticipate potential ethical dilemmas in future organoid research, regulate their use and management, and promote dialogue in anticipation of the medical potential of organoids and their future directions (Tang et al. 2022).

The objective of this study is to present the ethical and regulatory challenges concerning organoid research in one representative organization and global countries. This study reviews the regulatory and ethical considerations of organoids in global regulation. If there is currently no regulation on organoids, we use wide scope with key terms based on the latest research on organoids.

Countries selection

We included websites that discussed and described organoid-related legislation, or guidelines. The regulations for organoid in the European Union (EU) and nine countries: the United Kingdom (UK), the US, Canada, Japan, South Korea, Switzerland, Germany, China, Netherlands. These regions with the most organoid companies are in major development, and the countries chosen are those with the highest levels of activity in the organoid (Lee et al. 2021). In addition, we added one representative organization the International Society for Stem Cell Research (ISSCR) to check more accurate organoid-related regulations. We collected EU member state and EU regulations separately with the aim of analyzing differences in organoid regulation in the EU and EU member state independent regulations.

Data analysis

The organoid regulations were extracted from online available official regulatory websites. If there was no organoid regulation, we expanded the regulation to include the constituent parts of organoids such as stem cell or embryo in order to investigate it.

Systematic searches were conducted on the official websites of regulatory agencies in charge of approving the pharmaceutical products and organoid in nine nations, EU, and ISSCR. Only English-language websites were looked up for countries or organization such as the US, EU, Canada, and ISSCR where English is the official language. Official websites in English versions were searched for Japan and South Korea, as these two countries were well equipped to translate documents from local languages to English. Given that the English-language version of the websites is frequently not updated in a timely manner, the official websites for China, Switzerland, Germany, and the Netherlands were searched. Key terms extracted the abstracts and titles of organoid studies were identified by performing a word cloud analysis on unstructured text data (Huh 2018). Subsequently, crucial Mesh terms were extracted using text mining techniques. The wordcloud was created focusing on words with high frequency except duplicated word: “Organoid”, “Stem cell”, “Embryo”, “Induced pluripotent stem cells”. The word cloud was analyzed using R studio 4.3.1 (Fig. S1). All data was searched until May 12, 2023.

We extracted the organoid regulation from the investigating country, including laws, regulations, guidelines, and definitions, as well as information on specialist evaluation committees offered by regulators and/or governments. All documents used the latest contents updated in each country.

A systematic search obtained nine countries, the EU and one representative organization from official websites, a total of 26 legislations were included (Fig. 1). This study confirmed global organoid regulations, and since organoids originate from stem cells, related regulations were widely investigated (Fig. 2) (Lupton and Allwood 2017).

Figure 1. Overview of Global Organoid Legislation. The International Society for Stem Cell Research (ISSCR) only exist as guidelines, not regulations.

Figure 2. Study regulation flow diagram. Organoid regulation included that term for organoids, stem cells, and embryos. Organoid-related issues were Chimera, After 14 days Gastruloid, Germ cell, Informed consent, Data confidentiality, and Review process requirements. The outcome was categorized and studied into the definition of an organoid, ethical guidelines, and animal testing substitutes.

International classification and definitions of organoid

The definition of organoid in the ISSCR guideline is that tissue culture-derived structure growing in 3D and derived from stem cells that recapitulate the cell composition and a subset of the physiological functions of an organ through principles of self-organization. Only ISSCR has standard, formal definitions for organoid, there was no document directly describing the definition of organoid in any other legislations or regulations (Fig. 3). In US, EU, Japan, South Korea, China, Netherlands, Switzerland, Canada, Germany, UK, no standard, formal definitions for organoid are available.

Figure 3. Global organoid definition. ISSCR, International Society for Stem Cell Research; N/A, not applicable; X, Organoid is not defined; √, Organoid is defined.

Organoid ethical regulation

Therapeutic organoid regulations were identified in terms of expert review and protection of organoid donor data. In all investigated countries or representative organization, the regulation directly or indirectly states that organoids for therapeutic purposes also require review by experts (Table 1). Germany, the Netherlands, and Switzerland, expert review is mentioned in stem cell or embryo-related legislation, and in South Korea included in bioethics legislation. In other investigated countries and organization, expert review is specified in regulations or guidelines related to stem cell or human rights. Also, all investigated countries stipulate that any personal information associated with donors be encrypted or made anonymous when it comes to the safeguarding of organoid donor data. Donor protection was mentioned in statutes pertaining to therapeutic products, and medical scientific research involving human subjects in South Korea, the UK, Germany, Switzerland, and the Netherlands.

Table 1 . Comparing global ethic regulation of organoid.

Country or organization	Therapy		Model (laboratory)
	Review processes requirement	Donator data confidentiality	Review processes requirements by the committee	Informed consent requirement which donation of human cells and tissues	Donator data confidentiality	Making after 14 days Gastruloid	Chimera	Production of germ cells
European Union	Required	Required	N/A	Required	Required	Prohibited	N/A	Restrictive
United State	Required	Required	Required	Required	Required	Prohibited	Restrictive	Restrictive
Japan	Required	Required	Required	Required	Required	Prohibited	Restrictive	Restrictive
South Korea	Required	Required	Required	Required	Required	Prohibited	Prohibited	Restrictive
China	Required	Required	Required	Required	Required	Prohibited	Restrictive	Restrictive
Germany	Required	Required	Required	Required	Required	Prohibited	Prohibited	Restrictive
Netherlands	Required	Required	Required	Required	Required	Prohibited	Prohibited	Restrictive
Switzerland	Required	Required	Required	Required	Required	Prohibited	Prohibited	Restrictive
Canada	Required	Required	Required	Required	Required	Prohibited	Prohibited	Restrictive
United Kingdom	Required	Required	Required	Required	Required	Prohibited	Restrictive	Restrictive
ISSCR	Required	N/A	Required*	Required	N/A	Restrictive	Restrictive	Restrictive

ISSCR, International Society for Stem Cell Research; N/A, not applicable..

*Gastruloid: Exemption, Chimera (invitro: Recommend, Uterus of non-primates: Required), Germ cell: Exemption..

Organoids as models were classified into 6 types and global regulations were compared. In the overall countries, gastruloids, chimera, and germ cells are required to be reviewed by specialists before being developed in the lab. The EU had not regulation. The ISSCR guidelines specified that gastruloids was exempt from the review process, a chimera was recommended that expert review, a chimera that occurred in the uterus of a non-primate was required for that review, and germ cells were exempt from the review process. For organoid development, informed consent and donor data protection were required by all investigated countries or representative organization, but ISSCR was not mentioned organoid donor data protection in the guideline. Gastruloids are defined embryonic organoids that imitate many aspects of early mammalian development (Anlas et al. 2021). The 14-day limit is a boundary that prohibits researchers from culturing an in vitro gastruloid beyond 14 days after fertilization or the development of the primitive streak (Matthews and Moralí 2020). In overall countries, the gastruloids after 14 days, is outlawed by legislation, regulation, or guideline. However, only in the ISSCR guideline was in vitro organoids that mimic the bulk of organ functions as well as models of gastrulation or post-gastrulation events allowed to be researched without being subject to professional scientific and ethical monitoring procedures. Chimera research was prohibited in five countries that South Korea, Germany, Netherlands, Switzerland, Canada. A specific human-animal chimera was prohibited in the US and ISSCR, but under certain conditions, restricted research was permissible. Japan, UK, and China ban transplanting chimera embryos into the uterus, but not prohibit chimera research. Germ cell production was regulated by all investigated countries or organization, but the research was not prohibited (Table 2).

Table 2 . The organoid global regulation of alternative animal test.

Country or organization	Related global regulation or guideline	Replaced animal test
European Union	DIRECTIVE 2010/63/EU OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL of 22 September 2010 on the protection of animals used for scientific purposes	○
United State	H.R.6207 - Humane Cosmetics Act of 2021;H.R.7585 - Health Equity and Accountability Act of 2022;S.5002 - FDA Modernization Act 2.0 (2022) H.R.1744 - Humane Research and Testing Act of 2021; ICH S5(R3) Detection of Reproductive and Developmental Toxicity for Human Pharmaceuticals Guidance for Industry; (2021)	○
Japan	Act on Welfare and Management of Animals (Act No. 105 of 1973)	N/S
South Korea	COSMETICS ACT No. 18448, Aug. 17, 2021; LABORATORY ANIMAL ACT No. 18969, jun. 10, 2022	N/S
China	Guidelines for the ethical review of laboratory animal welfare People’s Republic of China National Standard GB/T 35892-2018 [Issued 6 February 2018 Effective from 1 September 2018]	N/S
Germany	Animal Welfare Act (1972)	N/S
Netherlands	Dutch Act on Animals used for scientific purposes (1977)	N/S
Switzerland	Animal Welfare Act of 16 December 2005 (position as at 1 January 2011)	N/S
Canada	Canadian Council on Animal Care Conseil canadien de protection des animaux, Guide to the Care and Use of Experimental Animals 2020;	N/S
United Kingdom	Animals (Scientific Procedures) Act 1986	N/S
ISSCR	ISSCR Guidelines for Stem Cell Research and Clinical Translation, Version 1.1 (2021)	○

ISSCR, International Society for Stem Cell Research; ○, Organoids have replaced animal test; Non-specific (N/S), Allow the alternative method, but the unclear scope..

Organoid regulation as technical aspects

All investigated countries and representative organization were positive about replacing animal testing. The EU, US and ISSCR noted that alternative approaches to animal models, such as organoids and improved testing based on modeling, are excellent and predictive scientific tools to protect human and animal health and the environment. The rest of the countries do not explicitly specify organoids in animal replacement methods, but all recommend the use of animal-free methods whenever possible and the use of means to reduce the number of animals provided as much as possible for scientific uses. The details of organoid legislation and additional important regulations, and guidelines relevant to organoid are provided in Table 1 and Supplementary Table 1.

Stem cell-derived organoid has the potential to treat many disorders that have no available treatments, but there are numerous regulatory and ethical issues associated with organoids. In this study, we investigated the definition of organoids, the regulation of various ethical issues of organoids, and regulations in the substitution of animal tests.

Except for ISSCR guideline, the organoid direct definition was not defined that any official regulation and legislation (International Society for Stem Cell Research [ISSCR] 2021). Nevertheless, currently, the term ‘organoid’ is used by the FDA Modern Act 2.0 and DIRECTIVE 2010/63/EU (EUR-Lex 2010; Congress.gov of USA 2022). For our results, ‘organoids’ were cursed with knowledge (Tullis and Feder 2023). The organoid definition that a basic concept has not appeared that any global regulation. The definition of terms in legislation or regulation is to resolve the ambiguity of terms and clarify the meaning and intent to be used. Legislation or regulation is a document that expresses the will of the country in language, that must be communicated properly since it has a significant impact on the course of action based on its contents and bears responsibility for the outcomes (Government of Canada 2022), but currently, the regulation of organoid definition is unclear.

There are currently no organoid regulations. Organoids are made from stem cells (Kim et al. 2020). Therefore, we additionally confirmed regulations for each country in the stem cell and embryo domains. Recently, the ISSCR guidelines have been revised, and regulations have been eased due to organoid research (ISSCR 2021). Eventually, regulations will be reformed for organoid research, but then there are no ethical regulations for organoids. The regulations must be established before research can proceed. Although there is no regulation at the current law level, there is guideline, and it is not harmonized.

Organoid ethical issues are still under discussion (de Jongh et al. 2022 ; Harris et al. 2022). Several national laws and guidelines restrict organoid research. ISSCR changed organoid regulation in 2021 which also included research on gastruloid. The 14-day limit is a boundary that prohibits researchers from culturing an in vitro gastruloid beyond 14 days after fertilization or the development of the primitive streak (Matthews and Moralí 2020). The new technological developments allow scientists to culture gastruloid in vitro beyond day 14. The ISSCR partially permitted scientific inquiry beyond the limits of the 14-day rule. The ISSCR guidelines also mention brain organoids. In 2019, Trujillo et al. measured electroencephalography (EEG) from human brain organoids using induced pluripotent stem cells. The researchers reported that human brain organoids showed a steady increase in electrical activity over several months and that the EEG patterns of the organoids were similar to premature infants (Trujillo et al. 2019). However, ISSCR reported that organoid technology has not yet reached the stage of replicating CNS tissue, and there is no biological evidence to support consciousness and pain issues in brain organoids, which should be discussed later (Hyun et al. 2021). Chimera studies are prohibited or restricted in all investigated countries. In overall organoid ethic studies, the human-animal chimera has morally ambiguous because it is feared that integration of human cells into the central nervous systems of animals might lead to ‘humanlike’ (Munsie and Gyngell 2018; Chen et al. 2019; Devolder et al. 2021). In our results, all investigated countries prohibited giving birth to chimeras or transferring chimera embryos to human or animal wombs. However, because organoids are rapidly evolving, it is critical to constantly watch breakthroughs in organoid technology that may necessitate new and more extensive ethical considerations.

The discussion on animal testing has been going on for a long time (Combes and Balls 2014). All investigated countries are changing their regulations regarding the alternative use of organoids for animal testing (Wange et al. 2021). Recently, the FDA’s 80-year-old requirement that new drugs must be tested on animals for approval has disappeared. FDA has introduced non-human or human biological-based testing methods (cell-based assays, organ chips, microphysiology systems, computer modeling, bioprinting) to replace non-clinical testing (Congress.gov of USA 2022). The organoids can have a significant impact on the replacement of non-clinical trials due to technological advances and regulatory changes.

Organoid research is necessary for reasons such as human intractable diseases and animal protection (Xu et al. 2018; Brooks et al. 2021; Ooft et al. 2021), but there are ethical issues and other concerns (Bredenoord et al. 2017; Munsie et al. 2017). Innovative scientific development suggests the possibility of producing brain organoids containing human nerve cells and leads to moral issues of organoids considering human dignity (Sawai et al. 2019). Additionally, it is important to determine the breadth of organoid research covered by current worldwide legislation and design relevant integrated policies in the new drug development process that is evolving as a result of the substitution of animal testing with organoids. Recently, organoid clinical trials are actively progressing according to clinical trial.gov (ClinicalTrials.gov 2023), and organoids are rapidly approaching as therapeutic agents beyond a model. Therefore, regulation needs to be adjusted according to the development speed of organoids.

This study has several limitations. First, organoid regulations are constantly being updated. Therefore, additional investigations are conducted according to the update, and more global regulatory research using the latest regulations is needed in the future. Second, organoids are made from stem cells. However, in iPS cell, which has been studied a lot recently, it is not mentioned in the regulations in many cases, so organoids made from iPS cells could not be analyzed separately. In the future, studies comparing organoid regulations developed from iPS cells are needed. Nevertheless, this study is the first to quantitatively analyze organoid regulations for 10 global countries and representative organization.

The organoid research is developing quickly. Organoids have the potential to treat many diseases for which there are no available treatments, but come with numerous ethical risks. However, organoid scientific researchers who encourage technical growth are more concerned with easing laws for unfettered study than with ethical concerns, ethics researchers who are concerned about the ethical issues of organoids are expressing concerns rather than the scope of scientific knowledge. Therefore, organoid regulations require the creation of convergence grounds to establish science-based research ethics and regulations, and integrated regulations are required. This study is the first cross-sectional study comparing global organoid regulations across 10 countries and ISSCR. In conclusion, based on the organoid definition, the scope of relevant regulations was identified, and the differences in global regulations were confirmed by checking ethical and technical regulations in each country. Considering no integrated regulations for organoid research, the results of this study can be used as a basis for establishing international guidelines in the future.

Supplementary materials can be found via https://doi.org/10.58502/DTT.23.0033.

The authors declare that they have no conflict of interest.

We appreciate a grant from the Korean government, South Korea (Ministry of Science and ICT, MICT; NRF- 2021R1F1A1062044) and by the Basic Science Research Program through the National Research Foundation of Korea funded by the Ministry of Education, South Korea (Grant Number 2021R1A6A1A03044296). The funder had no role in the trial design, data collection, data interpretation, or report preparation.