Where Americans Can Legally Access Expanded UC-MSCs

What “expanded” actually means

Every UC-MSC treatment starts with tissue donated from umbilical cords after healthy, consented births. From there, two very different products can be made.

The first is a minimally processed product: cells are isolated and, at most, rinsed, cut, or cryopreserved before use. No lab-grown expansion.

The second is a culture-expanded product: the cells are placed in a bioreactor or culture flask and multiplied over days or weeks until there are enough of them for a therapeutic dose, often tens or hundreds of millions of cells per infusion. This expansion step is what lets a clinic administer a meaningful cell dose systemically (IV) or into a joint or disc space, rather than a small, largely untested quantity.

That distinction, minimally manipulated versus culture-expanded, is also the exact line the FDA uses to decide how a product gets regulated.

Why the FDA treats expanded UC-MSCs as drugs

Under 21 CFR Part 1271, human cells and tissue products (HCT/Ps) are regulated one of two ways. Products that are minimally manipulated and used for a “homologous” purpose can qualify for the lighter 361 pathway, which doesn’t require pre-market approval. Everything else falls under Section 351 of the Public Health Service Act, which means the product is treated as a biologic drug and needs an Investigational New Drug (IND) application and, eventually, a Biologics License Application (BLA) before it can be marketed [1][2].

Culture expansion is specifically called out by the FDA as more than minimal manipulation. Growing cells in vitro to increase their number changes their biological characteristics relative to the original tissue, which is enough on its own to disqualify a product from the 361 pathway [1][3]. In practice, this means that no clinic in the United States can legally sell you an infusion of culture-expanded UC-MSCs the way you’d buy a vitamin drip. The only legal route is an FDA-authorized clinical trial.

The FDA has been explicit and increasingly active about enforcing this. In February 2026, it issued a warning letter to Dynamic Stem Cell Therapy over marketing an umbilical cord-derived product for allogeneic use to treat disease, precisely the kind of “351” biologic claim that requires an IND [4]. That followed warning letters to Evolutionary Biologics, Chara Biologics, Supreme Rejuvenation, New Life Medical Services, and Innate Healthcare Institute, plus a wave of 2026 letters targeting clinics in Florida, California, and Texas over unapproved exosome products [4]. The agency’s standing consumer warning, last updated in 2026, states plainly that products from human cells or tissues are “generally regulated as drugs and biological products” and that the FDA “has not reviewed or verified their quality, safety, purity, or potency” when they’re marketed outside that framework [5].

The one FDA-approved MSC therapy, and its limits

It’s worth being precise here, because the picture isn’t “the FDA has never approved a stem cell drug.” In December 2024, the FDA approved remestemcel-L-rknd (Ryoncil), an allogeneic, bone marrow-derived (not umbilical cord-derived) mesenchymal stromal cell therapy, for steroid-refractory acute graft-versus-host disease in children two months and older. It’s the first FDA-approved MSC product in the country, and the approval was based on a single-arm study of 54 pediatric patients showing a 70% overall response rate at day 28 [6][7].

Ryoncil demonstrates that culture-expanded MSC products can clear FDA review. It doesn’t change the underlying rule for UC-MSCs used in other conditions: outside a specific, narrow, approved indication, or outside an active clinical trial, expanded MSC therapy remains unapproved in the US. Americans with autoimmune disease, orthopedic injuries, neurologic conditions, or longevity goals cannot legally obtain a culture-expanded UC-MSC infusion at a US clinic for those purposes today.