ECGT Patients' Guide - Staging 1

Patient Safety in Cell & Gene Therapies: Guidelines and Resources

The International Society for Cell & Gene (ISCT) therapy brings together experts from around the globe who are committed to developing new innovative treatments that can have a positive and significant impact on many people’s lives. We are working towards improving both life expectancy and the quality of life of people living with some of the most challenging medical conditions in any society.


  • About CGT
  • What This Guide Is About
  • Approved and Proven vs. Unapproved and Unproven CGT Products
  • Characteristics of Unproven Therapies
  • Marketing of Unapproved and Unproven CGT Products
  • What Further Actions Can Healthcare Providers Take?
  • Reporting Mechanisms
  • Summary
  • Appendix

Cell and Gene Therapies (CGTs) is a rapidly growing field of medicine.

Some cell and gene-based products are now available as part of routine clinical practice in some, but not all countries, with more products in development. 

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Where proven and approved by regulators who independently assess their safety and effectiveness, these advances should be embraced and supported. In this context, well-studied and approved products can positively impact the lives of people living with certain conditions along with their wider family and support networks.

ISCT wholeheartedly supports the ethical development of cell- and gene-based products with patient safety and benefit in mind and further wants to drive forward improvements in practice.

However, some individuals and companies are providing unproven and unapproved products directly to the public, many of whom are in vulnerable situations as they search for a cure or answers in response to receiving a devastating diagnosis.

ISCT has major concerns about these unethical practices and seeks to ensure that the public is protected.


This guide provides information for healthcare practitioners on how to identify and distinguish safe and approved CGT products from those products that do not have a proven record of safety and efficacy, nor have received approval from appropriate regulatory organizations. 

Appendix 1 provides a glossary of sites that can further inform not only on CGTs but also how to determine which are proven and which are not. This guide also provides information on how to report concerns, or actual harm that has resulted from the use of unproven products.

Approved & Proven
CGT Products

CGT products must undergo a rigorous process of quality, safety, and efficacy demonstration under the oversight of appropriate regulatory agencies worldwide.

Approved and proven CGT products are provided to the public only after their quality, safety, and effectiveness have been demonstrated through carefully conducted and monitored clinical testing and reported in reputable peer-reviewed scientific journals.

Listings of approved products can be obtained from the websites of appropriate regulatory agencies (Appendix 2) and the Informational Resources webpage of the ISCT Committee on the Ethics of Cell and Gene Therapy (ECGT).

Unapproved & Unproven
CGT Products

A growing number of businesses have been providing unproven CGTs directly to the public.

These products are presented as safe and effective for a wide range of clinical conditions, but there is often little scientific evidence to support these claims. Further, false or misleading information is utilized to make these products appear scientific and evidence based.

Examples of unproven therapies that may be provided to the public and which are not supported by appropriate pre-clinical and clinical data include cell-based products, cell-derived products such as extracellular vesicles, and gene-based therapies including gene-modified cell therapies.


Unproven therapies typically meet some or all of the following criteria:

Unclear scientific rationale to suggest potential efficacy

Lack of understanding on the mechanism of action and/or the biological function to support clinical use

Insufficient data from in vitro assays, animal models, and/or clinical studies regarding the safety profile to support the use in patients

Lack of a standardized approach to confirm product quality and ensure consistency in manufacturing based on adherence to mandatory guidelines

Inadequate information disclosed to patients to enable proper informed consent

Administered utilizing non-standardized or non-validated methods

Supervision, review, and approval by appropriate national regulatory agencies is lacking

Payment, often of high fees, for the treatment(s) or for participation in so-called clinical studies (“pay-to-participate”)


Unproven CGT products are often marketed in ways that seem to be supported by more robust scientific evidence than actually exists.

These marketing strategies are collectively known as:

“tokens of scientific legitimacy”

These tokens of scientific legitimacy often include direct consumer advertising through social media, and can even mislead clinicians and other healthcare providers into choosing unproven interventions without fully considering the lack of appropriate scientific evidence. These persuasive tactics go beyond patient testimonials and celebrity endorsements. 

What Further Actions can Healthcare Providers Take
to Help the Public Evaluate CGTs?


Help potential recipients review the scientific data to determine if the product has had appropriate pre-clinical and clinical studies conducted. Sites that facilitate such discussion are included in Appendix 1.


In the absence of approved and proven cell therapies for a particular condition, help potential recipients identify appropriate clinical trials being conducted in a scientific manner and with proper regulatory oversight.


Report clinics or companies making therapeutic claims that cannot be scientifically substantiated to the relevant regulatory body, to patient advocacy groups and to professional organizations such as the ISCT and its ECGT committee. Patient advocacy groups and professional societies can distribute information that steers individuals toward legitimate providers and away from unethical ones.


Help individuals who are harmed through unproven cell therapies to report the event to regulatory agencies, patient advocacy groups, and ISCT and its ECGT committee, and/or relevant professional societies. As above, the more individuals involved in distributing information, the more likely it is that the information will get to people who need it.

Further details on reporting are provided below (Appendix 3).


In the unfortunate situation that an individual has been harmed through receiving an unproven CGT product it is important that such harm be reported to their physicians and caregivers and also to the proper regulatory agencies (Appendix 3).

These agencies can not only track such events, but they can also track and prosecute unscrupulous providers and practitioners. 


The use of unproven CGT-based treatments can be a risk not only to the individuals who receive the product, but also may have broader impact on families and caregivers.

Further, the unproven treatments can adversely affect legitimate studies attempting to develop safe and proven effective new therapies. ISCT urges healthcare providers to review all available information carefully and be alert to common features of unproven interventions to make the best-informed recommendations concerning CGTs and ultimately protect their patients.

A list of organizations that can provide further information is provided below.