Breakthrough is law. STeP is a guidance.

CDRH runs two voluntary programs that promise similar things: earlier engagement, priority review, a device that reaches the market sooner because its safety story is real. Breakthrough Devices and the Safer Technologies Program (STeP) read like siblings on FDA’s own website. One of them was written into the Food, Drug, and Cosmetic Act by Congress. The other was written into existence entirely by FDA guidance.

One program, a section of the Act

The Breakthrough Devices Program exists because the 21st Century Cures Act added a new section to the FD&C Act in 2016 — Section 515B, codified at 21 U.S.C. 360e-3. The statute does the deciding, in its own words: not later than 60 calendar days after a sponsor’s request, the Secretary shall determine whether the device meets the statutory criteria. That is a Congressional deadline sitting inside a Congressional program, enforceable the way any statutory duty is.

The other, a guidance document

STeP has no equivalent section. FDA published a draft guidance for it in September 2019 and finalized it in January 2021, describing a new administrative program — modeled deliberately on Breakthrough’s features — for devices that improve safety over current treatments but target conditions less severe than Breakthrough’s own life-threatening or irreversibly-debilitating threshold. Eligibility is built to be mutually exclusive: a device that meets Breakthrough’s criteria is excluded from STeP by the guidance’s own terms. Nothing in the FD&C Act mentions STeP by name, because nothing in the Act had to — FDA created the whole program under its general authority to administer premarket review, the same authority behind every guidance document CDRH publishes.

Both clocks say sixty days. Only one of them is a promise Congress can enforce.

Why the difference is load-bearing

STeP’s own guidance describes a similar rhythm to Breakthrough’s — an additional-information request around day 30, a final decision around day 60 — but describes it as what FDA intends to do, not what the Secretary shall do. That distinction is not a matter of tone. FDA’s own good-guidance-practices regulation, 21 CFR 10.115, says plainly that a guidance document creates no legally enforceable rights or obligations, for FDA or for anyone else. A missed statutory deadline under Section 515B is a missed legal duty. A missed target date under STeP’s guidance is FDA falling short of its own stated intention — a real thing to raise with a review division, but not the same thing to build a launch calendar around.

The practice

Two consequences follow for a program planning around either designation. First, the exclusivity is a sequencing decision, not a menu choice: if a device can plausibly meet Breakthrough’s criteria, STeP’s own eligibility terms foreclose it, so that question has to be answered before either Q-Submission goes in, not after one is denied. Second, build STeP’s 30- and 60-day markers into a calendar as FDA’s stated aim, with the slack a guidance target deserves, and reserve the confidence a hard deadline earns for Section 515B’s own 60 days. Neither designation shows up in the public clearance record either way — the 510(k) and PMA data FDA Radar ingests daily carries a K-number, applicant, product code, and decision, and no field for a Breakthrough or STeP designation attached to it, before or after the device authorizes. This is regulatory intelligence and method, never regulatory advice about which program fits a specific device or when to file for it; that judgment belongs to the regulatory professional who owns the submission strategy.