By Dr. David Greene, MD, PhD, MBA, Founder and CEO of R3 Stem Cell

If you’re considering regenerative treatment with R3 Stem Cell, you may have seen news about a warning letter the U.S. Food and Drug Administration (FDA) sent us in August 2026. Some of you have asked us about it directly, and we appreciate that. You deserve clear, honest answers, so we want to explain what the letter means, what it doesn’t mean, and what we’re doing about it.

We take this seriously

R3 Stem Cell takes its regulatory obligations seriously, and we respect the FDA’s role in protecting patients. We have responded to the agency, and we’re committed to an ongoing, constructive dialogue to address the points it raised.

We want to be clear about two things that matter most to patients. The warning letter does not involve any product recall. And R3 Stem Cell is not aware of any reports of patient harm associated with the matters raised in the letter.

R3 is not a manufacturer

There’s been some confusion about this, so we want to state it plainly: R3 Stem Cell is not a manufacturer and does not produce any biologics.

Where our therapies take place

The regenerative therapies described in our educational and consumer materials referenced by the FDA are performed at partner Centers of Excellence outside the United States, in accordance with the laws and regulations of the countries where they take place. Our materials include disclosures to that effect, and we’re reviewing our communications to make sure that distinction is clear to everyone who reads them.

Within the United States, any discussion of regenerative medicine options takes place within the physician-patient relationship, supported by transparent informed consent protocols.

Safety has always come first

“Patient safety has always been our first priority, and that hasn’t changed,” says Dr. Greene. “We respect the FDA and are working cooperatively with the agency. We want patients and families to have complete, accurate information when they consider their options. We remain committed to transparency, to research, and to the patients who trust us with their care.”

That commitment to information is why our licensed provider consultants spend considerable time with every patient. They are highly knowledgeable in regenerative medicine, and they walk patients through their options, the regulatory status of those options, and how our safety database works.

Our commitment to research

R3 recently launched its Institutional Review Board (IRB)-approved Global Observational Safety Database for umbilical cord-derived therapies. This first-of-its-kind database tracks regenerative patient outcomes and safety, so that what we learn from every treatment helps improve care for the patients who come after.

The R3 Stem Cell Research team has also authored 17 peer-reviewed publications. Topics include stem cell therapy for autism, cerebral palsy, premature ovarian failure, and systemic sclerosis, as well as intranasal delivery of stem cells and exosomes. Our most recent 2026 reviews, published in Frontiers in Drug Delivery, Frontiers in Aging Neuroscience, and Regenerative Therapy, focus on mesenchymal stem cells for arthritis, diabetes, and neurodegenerative disorders.

About R3 Stem Cell

R3 Stem Cell is one of the world’s largest providers of regenerative therapies, with more than 80 Centers of Excellence across 8 countries that have performed 30,000 stem cell procedures. Founded by Dr. David Greene, R3 combines patient care with clinical research and medical education. Our patient-funded programs support free treatment for veterans and ongoing research.

Questions? We’re here to help

If you have questions about your care or about this matter, please reach out to us directly. Call (844) GET-STEM or email info@r3stemcell.com. We’re always glad to talk with you.