Jurisdiction is a letter, not a field

A submission to FDA lands with one of three centers — the Center for Devices and Radiological Health, the Center for Drug Evaluation and Research, or the Center for Biologics Evaluation and Research — and for most devices which one is obvious before a submission is even drafted. For a growing share of what device companies actually build — a drug-eluting catheter, a diagnostic paired with a therapeutic, an autoinjector that is also a controlled-release formulation — it isn’t obvious at all, and no classification record, clearance database, or product code answers the question on its own.

One mode of action decides it

FDA’s product-jurisdiction rules, at 21 CFR Part 3 assign premarket review of a combination product to the center whose expertise matches the product’s primary mode of action — defined, at 3.2, as the single mode of action expected to make the greatest contribution to the product’s overall intended therapeutic effect. A device-led combination product is assigned to CDRH; a drug-led one to CDER. Nothing about that assignment appears in a product code, because the assignment happens before a product code is the right question to ask.

The request, and the clock FDA is on

A sponsor who cannot tell which mode of action predominates — or wants FDA’s own answer on the record before committing a submission strategy to it — files a Request for Designation under 3.7, naming its own recommended center and the reasoning behind it. FDA’s product jurisdiction officer then has 60 days from the filing date to issue a letter of designation under 3.8, naming the center with primary jurisdiction and any center FDA expects to consult alongside it.

The same section closes the loop its own deadline opens. If the product jurisdiction officer has not issued a letter of designation within 60 days of filing, the sponsor’s own recommended center becomes the designated agency component — automatically, without a second filing, without FDA saying so anywhere else.

A missed deadline here doesn’t leave the question open. It closes it — in favor of whichever answer the sponsor already gave.

What FDA publishes, and what it doesn’t

FDA does make some jurisdiction decisions public — as category-level policy, not as any one product’s outcome. The agency’s own Jurisdictional Updates page lists the general product types it has already worked through — breath-test combination products, drug-eluting cardiovascular stents, metered-dose inhalers with spacers — each with the reasoning FDA applied to the category as a whole. A specific sponsor’s own letter of designation is not on that page, is not in the 510(k) or PMA record that eventually follows it, and is not searchable in any public database FDA Radar or anyone else reads. The determination that decided which center reviewed a given product, and why, exists as a letter to that sponsor and nowhere else public.

The practice

A portfolio built around a combination product carries a fact no classification lookup will ever surface: which center is actually reviewing it, and on what reasoning, is settled by a letter this column cannot read any more than a competitor can. Understanding why a competitor’s combination-product filing went in as a device submission rather than a drug application means reading the record for the pathway it actually took — not searching for the designation itself, which was never published to find. What a specific product’s own primary mode of action is, or which center should review it, is a determination for a regulatory professional working that product’s own facts, filed through FDA’s own RFD process where it is genuinely unclear — this is a description of how that process works and what it leaves out of the public record, regulatory intelligence and method, never regulatory advice about any specific product’s classification.