U.S. flag An official website of the United States government
  1. Home
  2. Animal & Veterinary
  3. Safety & Health
  4. Product Safety Information
  5. FDA issues letter to veterinarians on the development & use of animal cells, tissues, and cell- and tissue-based products (ACTPs)
  1. Product Safety Information

FDA issues letter to veterinarians on the development & use of animal cells, tissues, and cell- and tissue-based products (ACTPs)

Dear Veterinarian:

We, the FDA’s Center for Veterinary Medicine (CVM), know that many veterinarians are interested in developments in regenerative medicine and animal cells, tissues, and cell- and tissue-based products (ACTPs).  Most ACTPs meet the definition of a new animal drug.1 Today, the FDA issued two new draft guidance documents,  which are intended to assist manufacturers of ACTPs in meeting the requirements for approval for new animal drugs.

The FDA understands the need for safe and effective ACTPs for use in animals, and we are taking actions to encourage development of these products.  In June 2015, we issued final guidance document # 218 about the regulation of cell-based products for animal use. This guidance document describes the FDA’s current thinking on the responsibilities of persons conducting research, manufacturing, or marketing ACTPs. In final guidance # 218, the FDA stated that when an ACTP is regulated by the FDA as a new animal drug, the person conducting the ACTP research and development must comply with applicable regulatory and statutory requirements for new animal drugs.  If you participate in any such activities, including the use of in-clinic cell/tissue processing systems, we encourage you to become familiar with the regulatory requirements for investigational use and marketing of a new animal drug.2

Soon after issuing guidance #218, we reached out in a letter to stakeholders reminding those involved in researching, manufacturing, and marketing cell-based products for animal use that such activities may require an investigational new animal drug exemption (INAD) or an approved new animal drug application (NADA). 

The first guidance FDA issued today, draft guidance #253, “Good Manufacturing Practices for Animal Cells, Tissues, and Cell- and Tissue-Based Products” provides manufacturers of ACTPs with recommendations for meeting requirements for CGMPs.  It addresses the methods, facilities and controls used for manufacturing ACTPs, including steps in recovery, processing, storage, labeling, packaging and distribution.  The guidance also addresses methods for preventing contamination and ensuring quality of the ACTP during manufacturing.

The second guidance, draft guidance #254, “Donor Eligibility for Animal Cells, Tissues, and Cell- and Tissue-Based Products” will assist sponsors, veterinarians and others that participate in the manufacture of ACTPs or perform any aspect of the ACTP donor eligibility determination. Selecting appropriate donors is critical to product quality and preventing the transmission of disease.  The concepts and principles in these guidance documents are consistent with the FDA’s Center for Biologics Evaluation and Research’s (CBER’s) regulations (21 CFR 1271 subparts C and D) and associated guidance documents for human cells, tissues, and cellular and tissue-based products.

We welcome your comments on the draft guidance documents issued today. The FDA is accepting public comments on both draft guidance documents until November 22, 2021, so that we may consider comments before issuing final guidance documents; however, comments on guidance documents are welcome at any time. Later this year, CVM will also post a webinar to discuss the guidance documents in more detail for interested stakeholders.  

At this time, there are no FDA-approved ACTPs for use in animals.  The FDA has concerns about unapproved ACTPs as they may not meet the agency’s standards for safety and effectiveness.  Unapproved ACTPs have not been reviewed by the FDA and may not be safe, effective, or properly manufactured or labeled.  Statements implying FDA approval or clearance of a laboratory, study, service, or otherwise, do not mean that a product is approved by the FDA, or that the manufacturer is operating in compliance with federal regulations.  By bypassing the FDA’s drug approval process, companies that make and sell unapproved ACTPs potentially put the health of animals and people at risk and could prevent an individual from seeking an appropriate diagnosis and treatment for the animal.  As always, FDA may take enforcement action against a person or entity marketing unapproved drugs, including ACTPs. 

If you encounter in your practice an ACTP-related adverse event, we encourage you to report it to the FDA.  For information on reporting, see Report a Problem

In 2018, the FDA established the Veterinary Innovation Program (VIP) that includes potential benefits for sponsors seeking FDA approval of ACTPs.  The goals of the program are to reduce uncertainty in the regulatory process, encourage development and research of innovative products, and achieve an efficient and predictable pathway to approval for ACTPs. 

The FDA also created a webpage that provides information on veterinary regenerative medicine and ACTPs. This webpage includes links to relevant guidance documents, presentations, and warning letters to firms marketing unapproved ACTPs.  The FDA also recently announced a listing of clinical field studies that are investigating ACTPs in veterinary patients.  The webpage provides animal owners, veterinarians, researchers and the public with information on clinical field studies, conducted under a file with FDA, that are being investigated for the use of ACTPs in veterinary patients.

We are offering this webpage as a resource because we’ve heard from veterinarians and pet owners who are eager to take part in clinical studies and avail their patients and pets of the potential that veterinary regenerative medicine may offer.  Connecting interested pet owners and their veterinary teams with relevant clinical studies also helps sponsors in generating data toward potential FDA approval.

The FDA, like the scientific community at large, believes that research in regenerative medicine holds great promise for future safe and effective treatments for many veterinary medical conditions.  However, the ultimate proof rests in obtaining interpretable data from well-controlled, well-designed scientific studies.  The results of this research will help all of us more fully understand the potential benefits and risks associated with ACTPs.  We encourage you to review the information and references provided in this letter and share this letter with others in your profession responsible for the research, manufacture, or clinical application of ACTPs.  If you have any questions about your responsibilities or if you need additional information, please contact AskCVM@fda.hhs.gov.


FDA’s Center for Veterinary Medicine

1 In general, cell-based products meet the definition of a new animal drug, if among other things, those products are intended for use in the diagnosis, cure, mitigation, treatment, or prevention of disease in animals, or are intended to affect the structure or any function of the animal.  See the Food, Drug, and Cosmetic Act, section 201(g)(1).

2 See 21 CFR 511.1 and 21 CFR 514.

Back to Top