Federal regulators have told a Scottsdale, Arizona company that the umbilical cord products it manufactures and sells to clinics are unapproved drugs and unlicensed biological products, and that inspectors found the company never validated whether it could make them sterile. The warning letter to R3 Medical Companies and its chief executive, Dr. David L. Greene, was issued by the FDA's Center for Biologics Evaluation and Research on Aug. 14 and posted publicly on Aug. 25.
The letter matters beyond one firm because of where the products went. According to the letter, Greene is also chief executive of affiliated R3 Anti-Aging clinics in Brentwood, Tennessee, and Beverly Hills, California, alongside the Scottsdale operation. Products reached those three clinics, other health care professionals, and additional clinics through a partner program.
For anyone weighing a cash paid stem cell or exosome treatment in Phoenix, Nashville or Los Angeles, this document is the clearest available picture of what regulators find when they inspect this category.
Inside the Warning Letter
FDA inspected two co-located facilities, Bello Bio and Regen Suppliers, between Nov. 17 and Dec. 16 of last year. The agency concluded the four products at issue, marketed as ReBellaWJ, ReBellaXO, ReBellaXOL and ReBellaCB, are drugs and biological products requiring premarket approval that they do not have.
The legal reasoning turns on a concept called homologous use. Human tissue products qualify for lighter regulation only if they perform the same basic function in the recipient as in the donor. Umbilical cord serves as a conduit, and cord blood forms and replenishes the blood forming system. FDA determined that marketing these products to treat conditions such as arthritis and inflammation falls outside that definition, which places them under full drug and biologics requirements.
The agency also noted that although two products are sold as exosome preparations, the manufacturing process described does not appear to isolate exosomes at all. The full warning letter is published on the FDA site.
Regulators had contacted this executive before. The letter references a notice sent in 2019 about marketing regenerative stem cell therapies for conditions including ALS, diabetes, kidney failure, Lyme disease, Parkinson's disease and stroke, and states that current websites indicate similar offerings continued.
Warning letters are not the end of a process. They notify a company of violations and give it a chance to respond, and FDA publishes them in a searchable warning letter database that patients can check by company name before paying for a treatment.
Conditions Named in the Marketing
The letter quotes company websites, social media accounts, and videos to establish that the products were promoted as treatments. Material cited includes claims that the products benefit neurologic conditions, heart, kidney and lung failure, autism, cerebral palsy, diabetes, Lyme disease, joint pain and erectile dysfunction, and that exosomes penetrate the blood-brain barrier with possible future benefit for Alzheimer's and Parkinson's disease.
None of those uses is supported by an approved application. FDA's consumer materials state plainly that the only stem cell products currently approved in the United States are blood-forming stem cells derived from umbilical cord blood, used for a narrow set of blood and immune disorders.
The conditions named share a pattern. They are chronic, serious, and in several cases have no curative treatment, which is precisely the population most vulnerable to a confident marketing claim. Autism and cerebral palsy appear in the cited material, meaning children were part of the addressable market.
FDA's patient information on regenerative medicine states the agency has received reports of blindness, tumor formation, and infections following use of unapproved products in this category.
Sterility Findings at the Scottsdale Facilities
The manufacturing observations are the most concrete safety element. FDA cited the firm for failing to validate the aseptic processes used to make products that are supposed to be sterile and are injected into patients.
Inspectors also found that samples were frozen and thawed before sterility testing. As the letter explains, freezing can destroy or compromise microbial content before the test runs, so contamination present beforehand may not be reliably detected. The firm had also not validated cleaning and disinfection of the biological safety cabinet where products are exposed to the environment.
A 24-month expiration date was assigned to products without supporting stability testing data. Written quality unit procedures, including procedures for approving or rejecting product and for handling complaints, had not been established at the time of inspection.
The company committed to temporarily suspending manufacturing while addressing inspection observations. FDA responded that this does not resolve the underlying violations, because the firm still lacks an investigational new drug application to study the products or an approved license to market them. The agency gave 15 working days to respond and warned that failure to address the matters may result in action without further notice, including seizure or injunction.
Checks Before Paying for Cell Therapy
Patients considering these treatments can verify a few things independently. Ask whether the specific product has an approved biologics license or whether the treatment is being given under an FDA-authorized clinical trial. Legitimate trials are listed at ClinicalTrials.gov and generally do not charge patients thousands of dollars for participation.
Ask what the product actually is, who manufactured it, and whether that manufacturer has been inspected. Warning letters are public and searchable on the FDA website by company name.
Treat breadth of claims as a warning sign. A single injectable product marketed for autism, arthritis, erectile dysfunction, and neurodegenerative disease is not describing a plausible mechanism.
Anyone who has received one of these products and develops fever, spreading redness, swelling, severe pain at an injection site, or new neurologic symptoms should seek medical care promptly and tell the clinician exactly what was administered. Adverse events can be reported to FDA through its MedWatch program, which accepts reports from patients directly and does not require a clinician to file on their behalf.
Key Questions Answered
What did the FDA say? The agency told R3 Medical Companies that its four umbilical cord-derived products are unapproved new drugs and unlicensed biological products, and cited significant manufacturing violations at two Scottsdale facilities.
Which clinics are connected? The letter states the executive who received it is also chief executive of affiliated clinics in Brentwood, Tennessee, and Beverly Hills, California, and that products reached those clinics, the Scottsdale clinic, and others.
What were the sterility findings? Inspectors found the firm had not validated aseptic manufacturing processes for products expected to be sterile, and that samples were frozen before sterility testing in a way that could mask contamination.
Which conditions were named in marketing? Cited material referenced neurologic conditions, organ failure, autism, cerebral palsy, diabetes, Lyme disease, joint pain, erectile dysfunction, and possible future benefit for Alzheimer's and Parkinson's disease.
Are any stem cell treatments FDA approved? Yes, but narrowly. The only approved stem cell products are blood-forming stem cells derived from umbilical cord blood, used for specific blood and immune system disorders.
What risks has the FDA documented in this category? The agency states it has received reports of blindness, tumor formation, and infections following use of unapproved products derived from human cells or tissues.
How can a patient verify a clinic? Ask whether the product has an approved license or is offered under an authorized clinical trial, ask who manufactured it, and search the FDA warning letter database by company name.
