Open consultation

Consultation on the regulation of Gene therapy medicinal products

Published 11 May 2026

Introduction

Advanced Therapy Medicinal Products (ATMPs) represent a category of human medicines typically intended to treat serious health conditions, including cancer and genetic disorders, with the potential for significant improvements in patient outcomes and quality of life, particularly in areas with high clinically unmet need.  The classification of a medicinal product as an ATMP is based on whether a given product fulfils one of the regulatory definitions of a Gene therapy medicinal product (GTMP), somatic cell therapy medicinal product (sCTMP) or tissue engineered product (TEP) (see Appendix 1). Of note, for a product that falls within the definition of a sCTMP or a TEP, and a GTMP, the regulations relating to the GTMP takes precedence^{[footnote 1]}.

ATMPs and applying a risk-based approach: ATMPs are often complex products that have specific design or manufacturing considerations: be it heterogenous starting materials (e.g. human cells for allogeneic and autologous cell therapies where inter-donor variability prevents complete standardisation), complex biological structures (such as viral vector-based medicines), or manufacturing processes which may include the use of novel materials or instruments. Such complexities often preclude easy-scaleup and/or traditional characterisation of the medicinal product. This complexity sometimes necessitates the adoption of a flexible and pragmatic approach to regulating these therapies. In medicines regulation, this is actioned through a risk-based approach (RBA; as outlined in EMA/CAT/CPWP/686637/2011). Indeed, the classification of a therapy as an ATMP in the UK is fundamentally intended to enable this approach. The RBA within the context of ATMPs was introduced to determine the extent of quality, nonclinical and clinical data required when applying for a marketing authorisation (MA), after accounting for product specific risk profiles. Without this flexibility, such medicines may never be marketed. However, any such deviation from standard data requirements is contingent on relevant scientific justifications being provided, typically based on product characteristics, demonstration of a positive benefit-risk balance, and consideration of potential implications of such deviations on product quality, safety, and efficacy.

Current regulatory considerations in the UK

In the UK, the primary legislation governing the authorisation, manufacture, import, distribution, sale, and supply of ATMPs are the Human Medicines Regulations 2012 (including unlicensed medicines). If the ATMP is used in a clinical trial, the applicable legislation is The Medicines for Human Use (Clinical Trials) Regulations 2004 and the products are known as Advanced Therapy Investigational Medicinal Products (ATIMP). For the remainder of this document, all references to ATMPs cover both these situations. Furthermore, and for the purposes of this consultation, any references to the Human Medicines Regulations 2012 and the Medicines for Human Use (Clinical Trials) Regulations 2004 should be interpreted as referring to the most current versions of these regulations, including any amendments in force at the time of publication of this document.

The full regulatory definition of a Gene therapy medicinal product under the Human Medicines Regulations 2012 (regulation 2A(2) and (3); see Appendix 1) is:

A “Gene therapy medicinal product” is a biological medicinal product which has the following characteristics —

it contains an active substance which contains or consists of a recombinant nucleic acid used in or administered to human beings with a view to regulating, repairing, replacing, adding or deleting a genetic sequence; and

its therapeutic, prophylactic or diagnostic effect relates directly to the recombinant nucleic acid sequence it contains, or to the product of genetic expression of this sequence.

A vaccine against infectious diseases is not to be treated as a gene therapy medicinal product.

Why the current ATMP definition requires revision

Advancements in manufacturing science and technology have significantly surpassed the scope of the current regulatory definitions of ATMPs (particularly GTMPs), as established under the Human Medicines Regulations in 2012. Several emerging modalities (including synthetic nucleic acid therapies, chemically produced mRNA constructs, and novel gene editing systems) do not fit clearly within the existing legislative categories, and some medicinal products utilising these technologies may not have a clear path to market under current legislative definitions of GTMPs.

For example:

• GTMPs manufactured using synthetic nucleic acid starting materials, such as chemically produced DNA templates rather than biological plasmids, can be functionally identical to their biological counterparts. Under current legislative definition of GTMPs, the medicinal product utilising the biological plasmid can be classified as a GTMP and developers can subsequently utilise a risk‑based approach to their developmental programme (see above), while the synthetic version does not meet the definition of GTMP. The definitions therefore require updating so that synthetic GTMPs could also be appropriately classified under the ATMP framework.
• Only gene editing systems based on recombinant nucleic acids can currently be licensed as GTMPs. This does not reflect the rapid evolution of genome‑editing technologies, which increasingly include non-recombinant nucleic acid systems, protein‑only editors and other emerging approaches that achieve precise, sequence‑specific genome modification without relying on recombinant constructs. These products may also benefit from the risk-based approach, yet the current definition prevents their consideration as GTMPs.
• The MHRA is also considering the creation of a dedicated framework for medicinal products in which the active substance is individualised to a patient’s characteristics. Currently, individualisation of ATMPs may be considered on a case-by-case basis. For example, certain individualised mRNA cancer immunotherapies may be classified as ATMPs.

Collectively, the limitations create uncertainty for regulators, developers and manufacturers; they also risk delaying patient access to innovative medicines. It is important that the appropriate regulatory framework is applied to each type of medicinal product to ensure a clear and proportionate approach while maintaining the required standards of quality, safety and efficacy. Furthermore, continued alignment of regulatory principles with major international regulatory partners is essential for ensuring international supply‑chains remain practicable, and UK developers are not disadvantaged.

Proposed changes to the Human Medicines Regulations: To address the limitations outlined above, we propose to make legislation to modernise and clarify the definition of GTMPs within the ATMP framework (regulation 2A of the Human Medicines Regulations 2012). These amendments will ensure that all products that cause sequence-specific genome edits are clearly classified as gene therapies. These amendments will also allow medicinal products manufactured using synthetic nucleic acids to be considered under the ATMP framework (alongside recombinant nucleic acid containing products), where said nucleic acids undergo transcription or translation. A main objective is to ensure that the ATMP framework remains proportionate and scientifically robust in light of contemporary innovation.

We propose to amend Regulation 2A of Human Medicines Regulations as follows (see Appendix 2):

(2) A “gene therapy medicinal product” is a medicinal product that has any of the characteristics listed in paragraph (2A) or (2B).

(2A) The characteristics are-

(a) the product contains or consists of a substance or a combination of substances that edit a target genome in a sequence specific manner; or

(b) the product contains or consists of cells which have been modified in that their genome has been edited in a sequence specific manner.

(2B) The characteristics are-

(a) the product contains or consists of a recombinant nucleic acid or synthetic nucleic acid, which:

a. is intended to-

i. regulate any nucleic acid sequence; or

ii. replace any nucleic acid sequence; or

iii. add any additional nucleic acid sequence; and

b. mediates its effect by being transcribed or translated; or

(b) the product contains or consists of cells subjected to a recombinant nucleic acid or synthetic nucleic acid, which:

a. is intended to-

i. regulate any nucleic acid sequence; or

ii. replace any nucleic acid sequence; or

iii. add any additional nucleic acid sequence; and

b. mediates its effect by being transcribed or translated;

(2C) A vaccine against infectious diseases is not to be treated as a gene therapy medicinal product.

The consultation: Through this consultation, we aim to seek views from stakeholders on whether the proposed approach is appropriate, proportionate and practically workable; whether the revised definitions capture the right categories of products; and whether any unintended consequences, regulatory gaps or operational challenges may arise.

Stakeholders are requested to provide their feedback via a survey. There are a total of 17 numbered questions in this consultation, grouped into 8 question sets. Stakeholders are also able to respond line-by-line to this consultation document. Instructions for providing line-by-line responses are found on the survey page.

Each question is reproduced in the next section, along with an explanation.

Question set 1

• (1) [LIKERT] Do you think that medicinal products produced from non-biological starting material should also be classified as Gene therapy medicinal products (GTMPs), if they meet other proposed criteria of GTMPs as outlined in Appendix 2?

Per current regulations, the classification of a medicinal product as a GTMP is inherently linked to a medicine being a biological medicinal product. Under this definition, a chemically synthesised substance or an enzymatically derived substance from a synthetic DNA backbone (which demonstrates equivalent design or functionality to traditional biologically derived GTMPs) would not currently fulfil the definition of a GTMP due to their starting material not being biological. This distinction is arbitrary, especially given the advent of new manufacturing technologies, as discussed in the introduction.

We propose to remove the fundamental requirement for GTMPs to be a biological medicine. Under the proposed framework, any synthetic or biological medicine can be a GTMP, if it meets other criteria for classification, as outlined in Appendix 2. Developers are encouraged to follow the most appropriate (chemical or biological) guidance for their specific product on a case by case basis, using a risk-based approach.

Question set 2

• (2) [LIKERT] Do you think that medicinal products containing recombinant or synthetic nucleic acids should be classified as Gene therapy medicinal products, only where said nucleic acids undergo transcription or translation?

Allowing chemically synthesised products to fall within the definition of GTMPs would enable both recombinant and synthetic nucleic acid–based products to be regulated under the GTMP framework. However, this raises a parallel challenge: ensuring that products not previously considered ATMPs do not become captured by an expanded definition. Reclassifying products that currently do not fall within the ATMP framework as ATMPs could create substantial regulatory disruption, requiring new manufacturing standards, new pharmacovigilance obligations and new clinical oversight for products that have already been safely developed, marketed and used under existing routes. This would risk unnecessary burdens on both industry and regulators without a corresponding gain in public health protection. A clear distinction is therefore needed between nucleic acid–based products that should appropriately fall under the GTMP category and those that should not.

To mitigate these challenges, we intend to consider medicinal products as GTMPs where the active substance contains a recombinant or synthetic nucleic acid, where said nucleic acid is transcribed or translated. Under this criterion, an active substance containing a recombinant or synthetic DNA/mRNA which is transcribed or translated will be a GTMP. Conversely, an active substance which contains a naturally occurring nucleic acid will not be classified as a GTMP (e.g unmodified bacteriophage, unmodified oncolytic viruses, etc). Similarly, any (manufactured) active substances where the nucleic acid is not transcribed or translated (typically antisense oligonucleotides, small interfering RNAs, small activating RNAs, micro-RNAs, etc.) will also not be considered a GTMP. Of note, mRNA products  derived from recombinant plasmids are currently classified as ATMPs since the starting materials are derived from a biological source. Under the proposed definitions, mRNA derived from synthetic starting materials will also be ATMPs (excepting vaccines for infectious diseases).  

Question set 3

• (3) [LIKERT] Do you think that medicinal products should be classified as Gene therapy medicinal products when their mechanism of action involves deliberate, sequence-specific genome editing, regardless of the composition of the active substance?

• (4) [LIKERT]  Do you think that medicinal products that modulate gene expression through epigenetic (or epitranscriptomic) mechanisms without altering a nucleic acid sequence should be classified as Gene therapy medicinal products?

Most gene editing approaches to date, including that used for the first licensed gene editing product (Casgevy), have relied on recombinant nucleic acid–based mechanisms, reflecting the technological landscape at the time the current definitions were established. However, the approval of this novel gene editing product has also highlighted the importance of a regulatory framework capable of accommodating new modalities, as emerging tools may achieve comparable gene editing effects without relying on traditional recombinant constructs. Per the current regulations, for a gene-editing product to be classed as a GTMP, it has to contain/consist of a recombinant nucleic acid. Such a definition fails to account for non-recombinant nucleic acid-based gene editing approaches that may be developed (or indeed, non-nucleic acid-based approaches, which theoretically may also be developed) and which may be more appropriately regulated under the ATMP regulatory framework.  
To mitigate these challenges, we propose to regulate any medicinal product whose mechanism of action incorporates genome editing as a GTMP, irrespective of the nature of the active substance. Genome editing will be interpreted to encompass effects on the genome only. The genome is interpreted to be the sum content of all genetic information in a cell (chromosomal and mitochondrial DNA). Such a genome modification is expected to be specific to a targeted genetic sequence; wherein the edit is fully predetermined, including both the exact genomic location targeted and the precise intended sequence after modification. Medicinal products that solely modify gene expression without directly altering genetic sequences will not fall within definitions of ATMP, unless they meet other criteria as laid out in Appendix 2. For example, medicines that edit the epigenome (e.g. histone deacetylase inhibitors), transcriptome (e.g. antisense oligonucleotides) or epitranscriptome (post-transcriptional chemical modifiers of RNA) will not be classified as a GTMP based on their epigenetic/epitrancriptomic modulation of gene expression. Products that produce long-lasting gene modulation through epigenetic or epitranscriptomic mechanisms, which may be functionally similar to products that cause sequence specific genome edits will also not be classified as a GTMP unless they meet other criteria as laid out in Appendix 2.

Additionally, this sequence-specific genome edit will be regarded as an intentional and designed feature of the product. This ensures that medicines causing broad, non-targeted genomic changes (such as certain chemotherapy or radiotherapy agents) are not misclassified as gene-editing products. Likewise, products introducing random integrations, such as some lentiviral vectors, will not be considered gene-editing solely based on these non-specific insertions. Furthermore, products that incorporate specific insertions (e.g., insertions caused by certain provirus vectors) but where the therapeutic effect does not necessitate a sequence-specific edit (such as scenarios in which the precise insertion site is non-critical provided expression of the transgene is achieved) may also fall outside the definition of gene-editing under this criterion. However, such products may still qualify as GTMPs if their nucleic acid cargo is intended for transcription or translation within the transduced cell, thereby meeting other classification requirements under the proposed amendments to the ATMP framework (Appendix 2).

Question set 4

• (5) [LIKERT] Do you think that classification of a product as a gene therapy medicinal product should include medicinal products for which the transferred genetic material is not directly responsible for the therapeutic, prophylactic, or diagnostic activity of the product?

Currently, the definition of a GTMP requires that the therapeutic, prophylactic or diagnostic effect of a GTMP must relate directly to the recombinant nucleic acid sequence it contains, or to the product of genetic expression of this sequence. Therefore, some medicinal products may be excluded. For example, Zalmoxis was an allogeneic T-cell therapy, where donor cells were genetically modified to incorporate a HSV-TK ‘suicide gene’, intended to mitigate graft-versus-host disease. Although the product was genetically modified, the mechanism of action of the gene modification (to act as a safety switch), was not directly responsible for the primary mode of action linked to the therapeutic indication/disease-label. Therefore, under current definitions, the criteria for being an advanced therapy medicinal product are met but it fails to meet the criteria for being classified as a GTMP, despite genetically modified cells comprising the active substance of the medicine (Zalmoxis was classified as a sCTMP).

We propose to remove the fundamental requirement for the recombinant (or synthetic) nucleic acid in Gene therapy medicinal products to exert a direct therapeutic, prophylactic or diagnostic effect in order to fulfil the definition of GTMP. Similarly, there will not be a requirement for a sequence-specific genome edit to exert a direct therapeutic, prophylactic or diagnostic effect in order for a product to be classified as a GTMP.  Instead, we propose that classification would be determined by the properties of the active substance, such as whether it contains a recombinant or synthetic nucleic acid that is transcribed or translated, or by its mechanism of action, including sequence-specific genome editing The removal of the requirement for a direct therapeutic, prophylactic or diagnostic effect within the specific definition of a GTMP does not diminish the overarching requirement for such a product to meet the definition of a medicinal product – to have properties for treating or preventing disease in human beings, restoring, correcting or modifying physiological functions through pharmacological, immunological or metabolic action, or making a medical diagnosis (as set out in Regulation 2 of the Human Medicines Regulations 2012).

Question set 5

• (6) [LIKERT] Do you think that medicinal products which exert their action through targeted genomic edits should be classified as Gene therapy medicinal products regardless of whether these edits occur directly within human cells or in other cells administered to the patient?

• (7) [LIKERT] Do you think that medicinal products which exert their action through the expression of a recombinant or synthetic nucleic acid should be classified as Gene therapy medicinal products regardless of if this activity occurs at the level of a human cell or in other cells administered to the patient?

There is ongoing uncertainty among some stakeholders about whether GTMPs must directly target human cells to fall within the ATMP framework. Established UK and EU regulatory precedent indicates that this is not the case. The MHRA and the European Medicine Agency’s Committee for Advanced Therapies have previously classified genetically modified bacteria as GTMPs even when the administered genetic sequence remains within the microbial system rather than integrating into human cells. This decision reflected the fact that the legislation (and subsequent guidance) does not require the repair, replacement, addition or deletion of a genetic sequence to occur “at the level of the human cell”, provided that a recombinant genetic sequence is administered to humans and exerts its effect through expression of that sequence.

The revised definition of GTMPs intends to ensure that products exerting their action through targeted genomic edits, or the expression of a recombinant or synthetic nucleic acid, are appropriately captured within the ATMP framework. This would be irrespective of whether the modification occurs in a patient’s own cells, in donor cells, or in an intermediate biological systems such as microbial vectors or engineered cell platforms.

Considerations on nomenclature, taxonomy, and subclassification of Gene therapy medicinal products

Historically, ATMPs have been broadly classified into gene therapies, somatic cell therapies, tissue engineered products or a combination ATMP which includes a medical device as an integral part of the product. While this regulatory classification is well defined under the original EU Regulation (EC) No 1394/2007 (and retained in the Human Medicines Regulations), there is no formal scientific consensus on how ATMPs, particularly gene therapies, should be further sub-classified. Academic literature often explores additional distinctions, for example: based on mechanism of action (e.g., gene addition, gene silencing, gene editing, or gene regulation); method of delivery (in vivo vs ex vivo); vector platform (viral vs non-viral; with viral products further classified as integrating or non-integrating vectors). However, such distinctions are not recognised within the Human Medicines Regulations which adopts a broader regulatory lens. This lack of granularity has allegedly led to oversimplifications and loss of nuance in public discourse. The resulting (false) conflation between products with significantly divergent risk profiles, mechanisms, and manufacturing implications can lead to misunderstanding, misinterpretation, and in some cases, inappropriate regulatory expectations. This may potentially affect access to healthcare. This divergence in academic taxonomies, public understanding, and regulatory requirements underscores the complexity and evolving nature of the ATMP landscape, and requires a nuanced approach to product licensing.

We seek to reiterate that the mechanism of action of a GTMP as defined currently in the Human Medicines Regulations 2012, does not always lead to the modification of a genome. Many non-genome modifying products have been successfully marketed under the auspices of a GTMP, some before the advent of gene editing technologies. We wish to highlight that the etymological roots of the term “gene therapy” derive from the therapeutic effect of genetic material. Such genetic material may be transiently expressed (as in the case of mRNA immunotherapies), episomal (e.g. certain AAV gene therapies), be permanently integrated into the (somatic) genome (e.g. certain lentiviral therapies) or cause the editing of targeted sections of the genome.

We propose to retain the umbrella term of GTMP to enable continued harmonisation with international terminology. We wish to reiterate that the primary driver of a classification of a product as a GTMP is to establish the legal basis to apply appropriate regulations and standards, including a risk-based approach during medicines licensing, and not to consider only the scientific rationale that sub-classifies such innovative medicines based on the immunological, pharmacological or metabolic action of constituent components. Hence, it is our opinion that any further subclassification of GTMPs does not serve any additional legal purpose in medicines licensing that is not already provided by the umbrella term of a “gene therapy medicinal product”. Accordingly,  there is no current intent to apply different regulatory requirements based solely on subclassification. Instead, supplementary guidance may be developed for specific types of products within the auspices of GTMPs, based on scientific considerations. We encourage all stakeholders to ensure appropriate educational material are developed and disseminated to guide public and patient communities regarding the specific benefit-risks of their medicine.

We also wish to highlight that the subclassification of a product under ATMPs (i.e. if a product is a gene, cell or tissue engineered therapy) does not provide a reliable indication of the product’s risk profile. Risk is a multifactorial consideration, shaped by factors such as pharmacokinetic properties, duration of effect, route of administration, degree of individualisation, therapeutic indication, and immunogenic or off-target effects, among others. In the case of a medicine with a delivery system (e.g. a viral vector, extracellular vesicles, cells etc.), this risk is considered for the overall medicinal product, with the risk profile of any vectors or other delivery vehicles considered together with their payload.

Finally, we also wish to stress that the classification of a product within the auspices of a GTMP is wholly independent of a classification of a product as a Genetically Modified Organism (GMO) under the GMO contained use regulations (2014) and/or GMO deliberate release regulations (2002). Just because a product is a GTMP does not automatically imply the product is a GMO (or vice versa). We seek to continue to work with stakeholders and improve regulatory understanding to streamline development of ATMPs in the UK.

Considerations on vaccines for infectious diseases

The MHRA proposes to maintain our position of not classifying any vaccine for infectious disease as a GTMP, irrespective of the nature of the active substance or its mechanism of action. The regulatory framework for vaccines which are administered to healthy individuals to prevent infection is well established, and is not proposed to be altered. For classification purposes, vaccines are expected to have prophylactic mode of action, i.e. prevention of an infectious disease in humans. If a product is intended to treat pathologies caused by the infection (e.g. malignancies), it is classified as a GTMP, provided it fulfils other criteria as laid out in Appendix 2. Finally, even though the terms “cancer vaccines” or “therapeutic cancer vaccines” may be used in other jurisdictions, based on definitions in the Human Medicines Regulations 2012, individualised mRNA cancer immunotherapies do not meet the regulatory definition of vaccines.   

Considerations on international regulatory definitions of GTMPs

The UK’s approach to ATMP regulation has been historically harmonised with the EU prior to withdrawal of the United Kingdom from the European Union. The UK continues to follow and contribute to the development of harmonised global standards and guidelines through  full membership of the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH). Furthermore, the UK remains part of the Council of Europe and the MHRA is a full member of the European Directorate for the Quality of Medicines & HealthCare (EDQM). The British Pharmacopoeia is also the UK National Pharmacopoeia Authority to the European Pharmacopoeia Commission.

The European Union has recently published the “Directive on the Union code relating to medicinal products for human use – Analysis of the final compromise text with a view to agreement”, which includes proposed amendments to the definition of Gene therapy medicinal products as applied within the EU.

‘gene therapy medicinal product’ means a medicinal product, except vaccines against infectious diseases, that contains or consists of:

(a) a substance or a combination of substances intended to edit the host genome in a sequence-specific manner or that contain or consists of cells subjected to such modification; or

(b) a recombinant or synthetic nucleic acid used in or administered to human beings with a view to regulating, replacing or adding a genetic sequence that mediates its effect by long lasting transcription or translation of the transferred genetic materials or that contain or consists of cells subjected to these modifications;

We have considered the EU text in developing the proposals and have outlined certain differences below.

Point	Proposed EU definition	Proposed UK definition (Appendix 2)	Reason for change
1	…substances intended to edit the host genome in a sequence-specific manner…	…substances intended to edit the target genome in a sequence-specific manner…	The term “host” may be interpreted to only refer to the patient receiving the therapy. Previous precedent explicitly states that the modification is not only at the level of a human cell. By replacing “host genome” with “target genome”, the revised definition more precisely captures the regulatory intent: to describe sequence-specific genomic modifications made to any cell regardless of whether it resides within the patient, a donor-derived cell, or an intermediate cell-based or microbial system.
2	…regulating, replacing or adding a genetic sequence that mediates its effect by transcription…	…regulating, replacing or adding a nucleic-acid sequence that mediates its effect by transcription…	While the MHRA has previously interpreted “genetic material” to include RNA, this interpretation remains implicit. By explicitly using “nucleic acid sequence”, the revised definition avoids ambiguity and ensures clarity regarding the inclusion of RNA-based products and non-natural constructs, synthetic analogues, or chemically modified nucleic acids.
3	…that mediates its effect by long-lasting transcription or translation…	…that mediates its effect by transcription or translation…	The inclusion of a duration-based qualifier may have implications on regulatory status of medicinal products that are currently considered as ATMPs, or have by precedent been classified as ATMPs under current regulations (such as mRNA immunotherapies for non-infectious diseases). The proposed UK definition does not currently include an explicit reference to “long lasting” transcription or translation. This reflects an approach which does not specify duration of effect within the legislative definition of GTMPs.

Question set 6

• (8) [LIKERT] Do you think the UK should consider classifying only those medicinal products which exert their effect through “long-lasting” transcription or translation of a recombinant or synthetic nucleic acid as Gene therapy medicinal products?

• (9) [FREE-TEXT] [OPTIONAL] In the context of the proposed amendments, to what extent should the Human Medicines Regulations 2012 mirror the proposed EU definition, or be tailored to better reflect the UK innovation landscape?

Question set 7: Overarching questions

• (10) [LIKERT] Do you agree or disagree with the proposed changes as outlined in Appendix 2, to the definitions of Gene therapy medicinal products?

• (11) [FREE-TEXT] [OPTIONAL] What implications, benefits or risks do you foresee the proposed changes to the definitions of Gene therapy medicinal products?

• (12) [FREE-TEXT] [OPTIONAL] Are there specific categories of products which, in your view, should be explicitly excluded from the revised definitions of a Gene Therapy Medicinal Product, and what scientific or regulatory rationale supports their exclusion?

• (13) [FREE-TEXT] [OPTIONAL] Please provide examples of products that were previously not classified as Gene therapy medicinal products (GTMP) but would now fall under the revised criteria (as proposed in Appendix 2) of a GTMP?

Question set 8: Impact of changes

• (14) [LIKERT] [OPTIONAL] With reference to the protected characteristics covered by the Public Sector Equality Duty set out in section 149 of the Equality Act 2010, or by section 75 of the Northern Ireland Act 1998, we have assessed that the proposals set out in Appendix 2 do not risk impacting people differently with reference to their protected characteristics, or in regard to the Rural Needs Act (Northern Ireland) 2016. Do you agree or disagree with this statement?

• (15) [FREE-TEXT] [OPTIONAL] We assume the main organisations impacted will be developers. We would welcome your view on if you agree or disagree with this, and how many developers you would expect to be affected by these changes. Please share any evidence to support your view.

• (16) [FREE-TEXT] [OPTIONAL] We assume that there will be no additional costs to business arising from these proposals. Do you agree or disagree? If you consider that there will be costs, please describe these and share any evidence to support your view.

• (17) [FREE-TEXT] [OPTIONAL] We expect that there will be a direct benefit for developers, and that the ultimate benefit of these changes will be improved health outcomes for patients. Do you agree or disagree, and please share any evidence to support your view, including on what these improved health outcomes might be.

APPENDIX 1: Current Regulation 2A of the Human Medicines Regulations 2012

 Human Medicines Regulations (2012) 2A.—

(1) In these RegulationsF2… “advanced therapy medicinal product” means any of the following products—

(a)a gene therapy medicinal product;

(b)a somatic cell therapy medicinal product; or

(c)a tissue engineered product.

(2) A “gene therapy medicinal product” is a biological medicinal product which has the following characteristics—

(a)it contains an active substance which contains or consists of a recombinant nucleic acid used in or administered to human beings with a view to regulating, repairing, replacing, adding or deleting a genetic sequence; and

(b)its therapeutic, prophylactic or diagnostic effect relates directly to the recombinant nucleic acid sequence it contains, or to the product of genetic expression of this sequence.

(3) A vaccine against infectious diseases is not to be treated as a gene therapy medicinal product.

(4) A “somatic cell medicinal product” is a medicinal product which has the following characteristics—

(a)it contains or consists of cells or tissues that—

(i)have been subject to substantial manipulation so that biological characteristics, physiological functions or structural properties relevant for the intended clinical use have been altered, or

(ii)are not intended to be used for the same essential function in the recipient as in the donor; and

(b)it is presented as having properties for, or is used in or administered to human beings with a view to, treating, preventing or diagnosing a disease through the pharmacological, immunological or metabolic action of its cells or tissues.

(5) A “tissue engineered product” is a medicinal product which—

(a)contains or consists of engineered cells or tissues; and

(b)is presented as having properties for, or is used in or administered to human beings with a view to, regenerating, repairing or replacing a human tissue.

(6) A tissue engineered product may contain—

(a)cells or tissues of human or animal origin;

(b)viable or non-viable cells or tissues; and

(c)additional substances, including cellular products, bio-molecules, biomaterials, chemical substances, scaffolds or matrices.

(7) A product is not a tissue engineered product if it—

(a)contains or consists exclusively of non-viable human or animal cells or tissues;

(b)does not contain any viable cells or tissues; and

(c)does not act principally by pharmacological, immunological or metabolic action.

(8) Cells or tissues are engineered if they—

(a)have been subject to substantial manipulation, so that biological characteristics, physiological functions or structural properties relevant for the intended regeneration, repair or replacement are achieved; or

(b)are not intended to be used for the same essential function in the recipient as in the donor.

(9) The following manipulations are not substantial manipulations for the purposes of paragraphs (4)(a) and (8)(a)—

(a)cutting;

(b)grinding;

(c)shaping;

(d)centrifugation;

(e)soaking in antibiotic or antimicrobial solutions;

(f)sterilisation;

(g)irradiation;

(h)cell separation, concentration or purification;

(i)filtering;

(j)lyophilisation;

(k)freezing;

(l)cryopreservation; and

(m)vitrification.

(10) In these Regulations F3… “combined advanced therapy medicinal product” means an advanced therapy medicinal product—

(a)which incorporates, as an integral part of the product, one or more medical devices or one or more active implantable medical devices; and

(b)the cellular part of which—

(i)contains viable cells or tissues; or

(ii)contains non-viable cells or tissues which are liable to act upon the human body with action that can be considered as primary to that of the medical devices.

(11) Where an advanced therapy medicinal product contains viable cells or tissues, the pharmacological, immunological or metabolic action of those cells or tissues is to be treated as the principal mode of action of the product.

(12) An advanced therapy medicinal product containing both autologous and allogeneic cells or tissues is to be treated as being for allogeneic use.

(13) A product which falls within the definition of a tissue engineered product and within the definition of a somatic cell therapy medicinal product is to be treated as a tissue engineered product.

(14) A product which falls within the definition of—

(a)a somatic cell therapy medicinal product or a tissue engineered product; and

(b)a gene therapy medicinal product,

is to be treated as a gene therapy medicinal product.]

APPENDIX 2: Proposed changes to Regulation 2A of the Human Medicines Regulations 2012

 (1) In these Regulations F2… “advanced therapy medicinal product” means any of the following products—

(a)a gene therapy medicinal product;

(b)a somatic cell therapy medicinal product; or

(c)a tissue engineered product.

(2) A “gene therapy medicinal product” is a medicinal product that has any of the characteristics listed in paragraph (2A) or (2B).

(2A) The characteristics are-

(a) the product contains or consists of a substance or a combination of substances that edit a target genome in a sequence specific manner; or

(b) the product contains or consists of cells which have been modified in that their genome has been edited in a sequence specific manner.

(2B) The characteristics are-

(a) the product contains or consists of a recombinant nucleic acid or synthetic nucleic acid, which;

a. is intended to-

i. regulate any nucleic acid sequence; or

ii. replace any nucleic acid sequence; or

iii. add any additional nucleic acid sequence; and

b.       mediates its effect by being transcribed or translated; or

(b) the product contains or consists of cells subjected to a recombinant nucleic acid or synthetic nucleic acid, which;

a. is intended to-

i. regulate any nucleic acid sequence; or

ii. replace any nucleic acid sequence; or

iii. add any additional nucleic acid sequence; and

b.       mediates its effect by being transcribed or translated;

(2C) A vaccine against infectious diseases is not to be treated as a gene therapy medicinal product.

(3) A “somatic cell medicinal product” is a medicinal product which has the following characteristics—

(a)it contains or consists of cells or tissues that—

(i)have been subject to substantial manipulation so that biological characteristics, physiological functions or structural properties relevant for the intended clinical use have been altered, or

(ii)are not intended to be used for the same essential function in the recipient as in the donor; and

(b)it is presented as having properties for, or is used in or administered to human beings with a view to, treating, preventing or diagnosing a disease through the pharmacological, immunological or metabolic action of its cells or tissues.

(4) A “tissue engineered product” is a medicinal product which—

(a)contains or consists of engineered cells or tissues; and

(b)is presented as having properties for, or is used in or administered to human beings with a view to, regenerating, repairing or replacing a human tissue.

(5) A tissue engineered product may contain—

(a)cells or tissues of human or animal origin;

(b)viable or non-viable cells or tissues; and

(c)additional substances, including cellular products, bio-molecules, biomaterials, chemical substances, scaffolds or matrices.

(6) A product is not a tissue engineered product if it—

(a)contains or consists exclusively of non-viable human or animal cells or tissues;

(b)does not contain any viable cells or tissues; and

(c)does not act principally by pharmacological, immunological or metabolic action.

(7) Cells or tissues are engineered if they—

(a)have been subject to substantial manipulation, so that biological characteristics, physiological functions or structural properties relevant for the intended regeneration, repair or replacement are achieved; or

(b)are not intended to be used for the same essential function in the recipient as in the donor.

(8) The following manipulations are not substantial manipulations for the purposes of paragraphs (4)(a) and (8)(a)—

(a)cutting;

(b)grinding;

(c)shaping;

(d)centrifugation;

(e)soaking in antibiotic or antimicrobial solutions;

(f)sterilisation;

(g)irradiation;

(h)cell separation, concentration or purification;

(i)filtering;

(j)lyophilisation;

(k)freezing;

(l)cryopreservation; and

(m)vitrification.

(9) In these Regulations F3… “combined advanced therapy medicinal product” means an advanced therapy medicinal product—

(a)which incorporates, as an integral part of the product, one or more medical devices or one or more active implantable medical devices; and

(b)the cellular part of which—

(i)contains viable cells or tissues; or

(ii)contains non-viable cells or tissues which are liable to act upon the human body with action that can be considered as primary to that of the medical devices.

(10) Where an advanced therapy medicinal product contains viable cells or tissues, the pharmacological, immunological or metabolic action of those cells or tissues is to be treated as the principal mode of action of the product.

(11) An advanced therapy medicinal product containing both autologous and allogeneic cells or tissues is to be treated as being for allogeneic use.

(12) A product which falls within the definition of a tissue engineered product and within the definition of a somatic cell therapy medicinal product is to be treated as a tissue engineered product.

(13) A product which falls within the definition of—

(a)a somatic cell therapy medicinal product or a tissue engineered product; and

(b)a gene therapy medicinal product,

is to be treated as a gene therapy medicinal product.]

APPENDIX 3: Legal duties

Assessment of the matters set out in section 2 of the Medicines and Medical Devices Act 2021

The Medicines and Medical Devices Act 2021 (‘the MMDA 2021’) received Royal Assent on 11 February 2021. We propose to make the legislative changes under consultation in this document, under Part 2 of the MMDA 2021, which provides powers to make regulations about human medicines.

Section 45 of the MMDA 2021 sets out that, before making regulations, the ‘relevant authority’ (in this case, the Secretary of State for Health and Social Care acting through the MHRA and jointly with the Department of Health in Northern Ireland) must carry out a public consultation. This consultation is conducted in line with the consultation requirements in section 2 of the MMDA 2021. Section 2 of the MMDA 2021states that in making regulations the overarching objective must be safeguarding public health and requires when considering whether regulations contribute to this objective, the relevant authority must have regard to:

1. the safety of human medicines;

2. the availability of human medicines;

3. the likelihood of the United Kingdom being seen as a favourable place in which to:

a. carry out research relating to human medicines,

b. conduct clinical trials, or

c. manufacture or supply human medicines.

We have assessed the proposals against each of these factors, and a summary of this assessment is set out below.

Safety

The proposed amendments relate to updates to legislative definitions of a class of medicines called Gene therapy medicinal products (GTMPs), to allow for advances in manufacturing and technologies. The proposed definitions do not alter the fundamental regulatory requirements applicable to GTMPs. All products captured under the revised definition will continue to be subject to the same rigorous standards of quality, safety and efficacy, including compliance with Good Manufacturing Practice, Good Clinical Practice and Good Pharmacovigilance Practice.

No new safety risks are introduced by these changes. Rather, the amendments make regulatory oversight more consistent by ensuring that all relevant products are captured within an established and well-understood framework. This reduces the risk of regulatory misclassification; whereby functionally equivalent products may otherwise be subject to different regulatory frameworks. By bringing synthetically manufactured gene therapies and genome editing products explicitly within the GTMP framework, the proposals ensure that appropriate and proportionate regulatory scrutiny, encompassing preclinical evaluation, clinical trial authorisation, marketing authorisation, and post-marketing surveillance, is consistently applied.

The MHRA therefore considers that the proposals support patient safety and safeguard public health, and that the benefits outweigh the risks, in accordance with the MHRA’s duties under the MMDA.

Availability

The proposals are expected to have a positive impact on the availability of human medicines. Advances in biotechnology have led to the development of innovative therapies, including synthetically manufactured nucleic acid medicines and genome editing products, which are not always clearly captured under the current legislative definitions.

By modernising the definition of GTMPs, the amendments remove potential regulatory barriers that could otherwise prevent such products from being authorised/licensed. This is particularly relevant in areas of high unmet clinical need, such as oncology and rare diseases, where novel therapies are emerging rapidly.

The changes will therefore facilitate the development, authorisation and supply of innovative medicines, ensuring that patients in the United Kingdom are able to access new treatments in a timely manner.

Favourability

The proposals are expected to enhance the attractiveness of the United Kingdom as a place to conduct research, clinical trials, and the manufacture and supply of human medicines.

By aligning the regulatory definition of GTMPs with current scientific principles and international regulatory practice, the amendments provide greater certainty for developers, reduces regulatory risk, and supports efficient product development pathways, including clinical trial and marketing authorisation applications.

The proposals are consistent with wider government ambitions set out in the Life Sciences Sector Plan and 10 Year Health Plan for England, supporting the MHRA’s role as an enabling regulator. Through mechanisms such as the Innovation Office and the Innovative Licensing and Access Pathway, the MHRA will continue to provide regulatory support to developers of advanced therapies.

Overall, the amendments are expected to contribute positively to the UK’s position as a favourable environment for innovation, without compromising regulatory standards.

National Health Service Act 2006

The National Health Service Act 2006 contains a number of overarching duties on the Secretary of State for Health and Social Care which apply to the exercise of functions, including in relation to the health service. Those we consider most relevant are:

The duty to continue to promote a comprehensive health service in England (section 1)

The duty as to improvement in quality of services (section 1A)

The duty as to the NHS Constitution (section 1B)

The duty as to reduce inequalities (section 1C)

We consider that these proposals support the duties in the National Health Service Act 2006 as they could expand the range of treatments that are Gene therapy medicinal products available to patients.

The proposals expand the definition of Gene therapy medicinal products, providing a viable legal basis for their licensing where currently none exists. For example, for products that are manufactured synthetically. The ability to licence these products is a necessary pre-condition to their provision in the health service, potentially expanding the range and quality of treatments available - although a regulatory approval of a medicinal product is separate to the decision whether to provide it via the National Health Service.

The MHRA has completed an equalities impact assessment for these proposals, that are expected to have a neutral to positive impact. By aligning regulatory classification more closely with scientific function rather than manufacturing origin, the proposal may reduce inconsistencies that could otherwise affect patient access to certain innovative medicines. Improved definitional clarity is also likely to support more consistent communication with patients and the public, which may assist informed decision-making across diverse groups. Overall, the proposals support a proportionate and equitable regulatory approach without introducing differential impacts on protected groups, while ensuring that oversight remains aligned with current scientific practice. 

APPENDIX 4: Glossary

Acronym	Meaning
ATMP	Advanced Therapy Medicinal Product. A category of medicines that includes Gene therapy medicinal products (GTMPs), somatic cell therapy medicinal products (sCTMPs) and tissue‑engineered products (TEPs).
GTMP	Gene Therapy Medicinal Product. A medicinal product as defined in Regulation 2A of the Human Medicines Regulations 2012.
sCTMP	Somatic Cell Therapy Medicinal Product. A medicinal product as defined in Regulation 2A of the Human Medicines Regulations 2012.
TEP	Tissue‑Engineered Product. A medicinal product as defined in Regulation 2A of the Human Medicines Regulations 2012.
RBA	Risk-based Approach. A regulatory flexibility mechanism that allows proportionate data requirements for complex ATMPs based on product specific risks.
DNA	Deoxyribonucleic acid. The molecule carrying genetic information in cells.
RNA	Ribonucleic acid. A molecule involved in gene expression, including mRNA, siRNA, microRNA and antisense oligonucleotides.
mRNA	Messenger RNA. A type of RNA that is translated into protein.
ASO	Antisense Oligonucleotide. A short synthetic strand of nucleic acid that binds RNA to modulate gene expression without being translated.
siRNA	Small Interfering RNA. A short RNA molecule that reduces gene expression through RNA interference.
GMO	Genetically Modified Organism. An organism (except human beings) whose genetic material has been altered as specified in The Genetically Modified Organisms (Contained Use) Regulations 2014. GMO status is separate from ATMP classification.
ICH	International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use.
EDQM	European Directorate for the Quality of Medicines and HealthCare.
MA	Marketing Authorisation. Legal approval to place a medicinal product on the market.
ATIMP	Advanced Therapy Investigational Medicinal Product. An ATMP used in a clinical trial.

Data protection and privacy

1. Introduction

You can read the MHRA Privacy Notice to find out in general terms the types of personal data we process and why; as well as information about your rights and how to raise concerns.

This privacy notice sets out the approach to this consultation that the MHRA will take to handle information appropriately and to comply with information legislation.

This privacy notice covers documents gathered and created during this consultation and anything in which information of any description is recorded, whether in paper or electronic form. 

2. Legal requirements for information management and privacy

The consultation complies with data protection legislation including the Data Protection Act 2018 and the UK General Data Protection Regulation (UK GDPR). 

We rely on UK GDPR Article 6(1)(e) as our legal basis for processing your personal data. This allows us to process personal data when this is necessary for the performance of our public tasks in our capacity as a regulator.

Information provided to the MHRA may include some special category personal data. Our lawful basis for processing such information is set out in UK GDPR Article 9(2)(i) and the Data Protection Act Schedule 1, Part 1(3). Both relate to situations where the processing is necessary for reasons of public interest in the area of public health.

3. Lawful basis and purpose of processing personal information

The consultation may collect and use personal information for the purpose of gathering views to inform our approach to potential regulation of Advanced Therapy Medicinal Products. 

In the case of personal information, the purpose is to read and analyse the information provided to improve understanding of the key considerations raised by individuals and organisations for our work to effectively regulate Advanced Therapy Medicinal Products.

The information may also be used to help explore issues and direct further areas of research. Where this may be done, no personal information will be used.

4. Security and confidentiality

Only members of the MHRA working on this consultation will have access to the data. These would include the following: Healthcare, Quality and Access; Safety and Surveillance and the Inspectorate. Authorised personnel from SurveyOptic Ltd (the online survey platform) will also have access to personal information. Those who do are aware of their obligations and responsibilities when handling personal and confidential information. They are subject to employment, contractual and other professional obligations regarding confidential and official information, both during the review and afterwards. 

All personal and confidential information is stored securely to prevent loss or inappropriate access. 

5. Sharing information

The MHRA will hold the personal information you provide in this consultation and use it for the purpose of informing the approach to regulating Advanced Therapy Medicinal Products.

Information published in response to this consultation, including personal information, may be published or disclosed in accordance with the access to information regimes. These are primarily the Freedom of Information Act 2000 (FOIA), the Data Protection Act 2018 (DPA), the UK General Data Protection Regulation 2016 (GDPR) and the Environmental Information Regulations 2004.

We would not publish data where it would lead to a breach in data protection principles.  However, the information you send us may need to be published in a summary of responses to this consultation.

6. Retention and destruction of documents

Following the consultation, a response to the consultation will be published outlining its findings and recommendations. It is anticipated that the final response will not include any personal data. The contributions will be retained for a period of 5 years after the final consultation response has been published.

7. Rights

You have several rights which are outlined in the MHRA Privacy Notice. For greater detail on when they apply please refer to the Information Commissioner’s website If you wish to exercise any of your rights, or have any questions or concerns, please contact our Data Protection Officer at dataprotection@mhra.gov.uk.

1. Paragraph 14 of regulation 2A of the Human Medicines Regulations 2012 ↩