Missing one 1271.10 criterion reclassifies the product

This blog has already covered how a Request for Designation sorts a combination product among FDA's centers without deciding what that product actually has to submit. Human cells, tissues, and cellular and tissue-based products — HCT/Ps — run into a different sorting question first, one that doesn't decide which center reviews the product but whether it needs premarket review at all. 21 CFR 1271.10 sets four conditions for a tissue product to be regulated solely under section 361 of the Public Health Service Act, on registration and current good tissue practice alone, instead of the drug or biologic pathway everything else on this blog's usual beat eventually reaches. All four conditions have to hold. A tissue bank that clears three of them and treats the fourth as close enough hasn't found a lighter version of Section 361 — it has built a product that was never eligible for it.

Two pathways, sorted before any premarket question is asked

Section 361 of the Public Health Service Act lets FDA regulate certain HCT/Ps to prevent the spread of communicable disease, through registration, donor-eligibility screening, and current good tissue practice under 21 CFR Part 1271 — without the premarket review a drug or biologic requires. Section 351 covers everything that falls outside that narrower authority, and a product that lands there needs an investigational new drug application before human use and a biologics license application before it can be marketed at all. 1271.10 is the provision that decides which side of that line a given HCT/P sits on, and it asks the question before anything about safety or effectiveness data comes up — a 361 product never has to answer those questions to reach the market; a 351 product can't reach it without answering them first.

Four conditions, and none of them is optional

1271.10(a) sets out four criteria, and the section is explicit that an HCT/P is regulated solely under 361 only if it meets all of them. The product has to be minimally manipulated. It has to be intended for homologous use only. Its manufacture can't combine the cells or tissue with another article, except water, crystalloids, or a sterilizing, preserving, or storage agent that doesn't itself raise a new clinical safety concern. And it either has no systemic effect and doesn't depend on the metabolic activity of living cells for its primary function, or — where it does have a systemic effect or does depend on that metabolic activity — it's limited to autologous use, allogeneic use in a first- or second-degree blood relative, or reproductive use. Clearing three of the four leaves a product exactly as unregulated-under-361 as clearing none of them; the section doesn't score a product, it tests it.

Homologous use turns on what was said, not just what was done

The second criterion is the one that catches the most tissue processors off guard, because it isn't answered by the manufacturing process alone. FDA's own guidance evaluates homologous use — repairing, reconstructing, replacing, or supplementing a recipient's tissue with an HCT/P that performs the same basic function in the recipient as it did in the donor — through the objective intent shown by the product's own labeling, advertising, and other representations, not through a lab's private understanding of what the tissue is biologically capable of. This blog has already covered how a device's own stated use, not its underlying technology, is what a regulatory reviewer actually tests; the same discipline governs here. A birth-tissue product processed identically start to finish can clear the homologous-use criterion under labeling that claims structural tissue replacement and fail it under labeling that adds a regenerative or anti-inflammatory claim reaching past that same tissue's basic function in the donor — with nothing about the manufacturing itself having changed at all.

The fallback isn't a smaller filing

A product that fails any one of the four criteria doesn't drop into a scaled-down HCT/P filing built for the near-miss cases. It becomes a drug, a biological product, or a device subject to the full premarket framework that applies to whichever of those it is — an IND before any clinical use, a BLA or comparable approval before marketing, and the manufacturing controls that pathway requires, in place of the registration-and-donor-screening framework Part 1271 runs for a 361 product. Nothing about that consequence phases in gradually; a product either meets all four 1271.10(a) criteria or it doesn't reach section 361 at all.

Where this meets the file

A tissue-product classification file needs each of the four criteria tracked as its own dated finding, with the homologous-use finding specifically tied to the product's current labeling and advertising rather than to a manufacturing description that hasn't changed since launch — because labeling is exactly the piece of this test that can move without anyone touching the process behind it. An HCT/P classification worksheet built around that structure is previewed in the launch catalog. If your program classifies tissue products differently, the shelf takes that correction directly.