FDA runs four distinct expedited programs for drugs and biologics that treat serious or life-threatening conditions — Fast Track, Breakthrough Therapy designation, Accelerated Approval, and Priority Review — and a single product can qualify for more than one at the same time. They are not tiers of one program and they don’t all do the same thing: two speed up FDA’s engagement during development (Fast Track, Breakthrough Therapy), one changes what counts as sufficient evidence for approval (Accelerated Approval), and one shortens FDA’s review clock once an application is filed (Priority Review). This page maps how the four relate, where their eligibility criteria overlap and diverge, and whether they stack. For the full eligibility criteria, request process, and FDA’s own review-performance data on any single pathway, see the dedicated pages linked throughout.
The four programs, at a glance
| Program | What it targets | Statutory basis | What it confers |
|---|---|---|---|
| Fast Track | A serious/life-threatening condition plus nonclinical or clinical data showing the drug has the potential to address an unmet medical need | FDA Modernization Act of 1997; FD&C Act §506(b) | More frequent meetings and communication with FDA during development; eligibility for rolling review (submitting completed sections of an NDA/BLA before the full application is done) |
| Breakthrough Therapy designation | A serious condition plus preliminary clinical evidence that the drug may show substantial improvement over available therapies on a clinically significant endpoint | FDA Safety and Innovation Act (FDASIA) of 2012 | All Fast Track features, plus intensive FDA guidance starting as early as Phase 1 and involvement of senior FDA managers |
| Accelerated Approval | A serious condition where the drug has an effect on a surrogate or intermediate clinical endpoint that is reasonably likely to predict clinical benefit | 21 CFR Part 314 Subpart H (drugs); 21 CFR Part 601 Subpart E (biologics); amended by the Food and Drug Omnibus Reform Act (FDORA) of 2022 | Marketing approval before long-term clinical benefit is confirmed, in exchange for a required postmarketing confirmatory trial |
| Priority Review | An already-filed application for a drug that, if approved, would provide a significant improvement in safety or effectiveness for a serious condition | Part of the PDUFA review-goal framework | A 6-month FDA review goal from filing, versus the 10-month standard review goal |
What “expedited” does and doesn’t mean
None of the four programs lowers the evidentiary bar for safety, and only Accelerated Approval changes what counts as sufficient evidence for the initial approval decision itself (a surrogate endpoint rather than a confirmed clinical-outcome endpoint). Fast Track and Breakthrough Therapy are development-phase designations — they change how much and how early a sponsor interacts with FDA, not what the final application has to show. Priority Review is neither a development-phase designation nor an approval standard; it’s a review-timeline commitment FDA makes once a complete marketing application has actually been filed. A drug can move through the entire expedited toolkit and still receive a Complete Response Letter if the application doesn’t ultimately support approval.
Fast Track
Fast Track is the entry point of the four: a sponsor requests it, usually early in development, on the basis that the drug addresses a serious condition and shows the potential — not yet proof — of meeting an unmet medical need. FDA can grant it based on nonclinical data alone. Its main practical value is procedural: more frequent formal and informal meetings with the review division, and eligibility for rolling review of the marketing application. If the criteria that justified Fast Track designation are still met when the application is filed, the product also becomes eligible for Priority Review and, if the surrogate-endpoint criteria are separately met, Accelerated Approval.
Breakthrough Therapy designation
Breakthrough Therapy designation sits a step above Fast Track on the strength-of-evidence axis: it requires preliminary clinical evidence (not just nonclinical potential) that the drug may offer a substantial improvement over existing therapies on a clinically significant endpoint. Every product with Breakthrough Therapy designation automatically has all of Fast Track’s features, plus more intensive, earlier FDA involvement. For the full eligibility criteria, the request process, and how it’s distinguished from orphan drug designation, see FDA Breakthrough Therapy Designation: Criteria and Process.
Accelerated Approval
Accelerated Approval is the only one of the four that changes the approval standard itself. It lets FDA approve a drug for a serious condition based on an effect on a surrogate endpoint (or an intermediate clinical endpoint) that is reasonably likely to predict clinical benefit, rather than waiting for a fully confirmed clinical-outcome endpoint. In exchange, the sponsor is required to conduct a postmarketing confirmatory trial to verify the expected clinical benefit — and since FDORA’s 2022 amendments, FDA has explicit authority to require that trial be underway (not merely promised) at or shortly after the time of approval, along with an expedited procedure for withdrawing the approval if the confirmatory trial fails to verify benefit. See the Accelerated Approval dictionary entry for the full regulatory citation and worked criteria.
Priority Review
Priority Review applies once a complete marketing application (NDA or BLA) has been filed. If FDA determines the drug, if approved, would represent a significant improvement in safety or effectiveness for a serious condition, it commits to a 6-month review goal measured from filing, against the standard 10-month goal set under the Prescription Drug User Fee Act (PDUFA) framework. A product can be designated for priority review because it already held Fast Track or Breakthrough Therapy status, or independently at the time of filing even without either of the earlier designations. See FDA Priority Review for the full eligibility criteria and how it interacts with priority review vouchers.
Can a product hold more than one at the same time? Do they stack?
Yes. The four programs operate on different axes — development-phase engagement, approval-evidence standard, and review timeline — so they aren’t mutually exclusive, and FDA’s own framing of the four as a set (rather than a ladder where only one applies) is intentional. A single drug can enter development with Fast Track designation, be elevated to Breakthrough Therapy designation once early clinical signal supports it, seek approval on a surrogate endpoint under Accelerated Approval, and have its application reviewed under the 6-month Priority Review clock — all at once. What’s true is that each additional designation still requires independently meeting that program’s own criteria; holding one doesn’t automatically confer another except in the specific case noted above, where Fast Track or Breakthrough Therapy status can carry a product into Priority Review eligibility if the underlying criteria still hold at filing.
How this differs from orphan drug designation
Orphan drug designation is evaluated on a completely different axis from all four expedited programs: it turns on how rare the disease is (fewer than 200,000 patients in the U.S., or a rarer disease where cost recovery is unlikely), not on the strength of clinical evidence, the endpoint type, or where the application sits in the review queue. A drug can hold orphan designation and any combination of the four expedited programs simultaneously, or none of the expedited programs at all — the two systems are independent and a sponsor typically pursues both wherever the underlying facts support them.
Frequently asked questions
What are FDA’s four expedited programs?
Fast Track, Breakthrough Therapy designation, Accelerated Approval, and Priority Review. FDA groups and describes all four together on its own public-facing “Fast Track, Breakthrough Therapy, Accelerated Approval, Priority Review” resource pages, which is the direct source for this page’s framing.
Can a drug have both Fast Track and Breakthrough Therapy designation?
In practice a drug that earns Breakthrough Therapy designation already has everything Fast Track confers, since Breakthrough Therapy status includes all Fast Track features by design. Sponsors sometimes hold Fast Track first and are later granted Breakthrough Therapy designation as clinical evidence accumulates.
Does Priority Review require Fast Track or Breakthrough Therapy first?
No. Priority Review can be granted independently at the time of filing if the application meets its own significant-improvement criteria, regardless of whether the product held Fast Track or Breakthrough Therapy status earlier in development.
Is Accelerated Approval the same as Priority Review?
No. Accelerated Approval changes what evidence is sufficient for the approval decision itself (a surrogate endpoint). Priority Review changes how quickly FDA reviews the completed application. A drug can have either, both, or neither.
Does an expedited program guarantee approval?
No. All four programs affect the pace or structure of FDA’s engagement and review; none of them lowers the underlying safety standard or guarantees a favorable outcome. An application that entered through any or all of the four programs can still receive a Complete Response Letter if it doesn’t ultimately support approval.
