Why a 361 HCT/P Product Is Not the Same as an FDA-Approved Biologic Drug

A 361-regulated human cell/tissue product (HCT/P) is legally restricted to structural, homologous, generally non-systemic or topical-type use. It is not reviewed by FDA for safety or effectiveness, and it is not interchangeable with an FDA-approved 351(a) biologic drug — regardless of how a product is marketed.

What "structural / homologous use only" means

Under 21 CFR § 1271.10(a)(2), a product can only qualify for the lighter Section 361 pathway if it is intended for homologous use — defined at 21 CFR § 1271.3(c) as "the repair, reconstruction, replacement, or supplementation of a recipient's cells or tissues with an HCT/P that performs the same basic function or functions in the recipient as in the donor." In practice, this means the tissue must be used to do essentially the same physical job it did in the donor's body — for example, using bone tissue to structurally replace bone, or skin tissue to structurally replace skin.

The moment a product is used or marketed for a different function than it performed in the donor — for example, injecting a birth-tissue product for its purported anti-inflammatory, immune-modulating, or regenerative signaling effects rather than for structural replacement — it is non-homologous use. That failure, standing alone, disqualifies the product from Section 361 regardless of how minimally it was processed.

Why this distinction has real legal consequences

21 CFR Part 1271 requires HCT/P manufacturers to register with FDA and list their products (21 CFR § 1271.10(b)). Some marketing materials describe this registration as "FDA-registered" in a way that implies FDA approval. It does not. Registration is a database listing; it involves no FDA review of safety or effectiveness. FDA has stated publicly and repeatedly that clinics claiming their products fall outside FDA's regulatory authority, or implying FDA-registration equals FDA-approval, are incorrect. In a 2019 statement, then-FDA Commissioner Scott Gottlieb and CBER Director Peter Marks said: "We remain very concerned that countless clinics across the country continue to market violative stem cell products to patients, claiming that they don't fall under the regulatory provisions for drugs and biologics. This is simply not true."

21 CFR Part 1271 — the governing framework

21 CFR Part 1271 sets out the full regulatory scheme for HCT/Ps, including donor eligibility and screening (Subpart C), Current Good Tissue Practice / cGTP (Subpart D), and registration/listing requirements (Subpart B). This is a real and legitimate federal framework — but it is a narrower, disease-transmission-focused framework (its statutory basis, 42 U.S.C. § 264, is a communicable-disease-control authority), not a safety-and-effectiveness review framework. That is the core structural reason a compliant 361 product is legally distinguishable from an FDA-approved drug: one has been reviewed for whether it works and is safe at the dose/route/indication studied; the other has not been reviewed on either question at all, so long as it stays within its narrow, compliant lane.

The practical bottom line for a member of the public

• If a product is being offered by injection or IV infusion for a systemic therapeutic effect on a disease or condition (anti-inflammatory effect, disease treatment, "regeneration" of an organ system), it is very unlikely to be lawfully marketable as a 361 product, and it should have an active IND if it is being used investigationally in humans.
• "FDA-registered" tissue bank status is not the same as FDA product approval. Ask specifically: has FDA approved or licensed this product for this use? If the answer is no, the product is being offered outside FDA's premarket review of safety and effectiveness for that use, whatever its underlying HCT/P registration status.
• A product with a genuinely compliant 361 profile is, by legal definition, limited to structural/homologous, generally non-systemic use — not a general-purpose regenerative therapy.