An FDA review framework glossary.

Prepared September 15, 2026 · Publisher review required · No clinician review claimed

The acronyms that appear in retatrutide coverage, what they mean, and where the FDA documents them. Definitions first; interpretation is a separate step.

Application types

BLA — Biologics License Application

The application type a sponsor uses to seek FDA approval of a biologic product. Retatrutide, like other peptide-based therapeutics, is a biologic; Lilly’s August 5, 2026 statement describes a planned BLA. S25: Drug Applications — FDA

NDA — New Drug Application

The application type for non-biologic (small-molecule) drugs. PDUFA VII performance goals apply to original BLAs and NME NDAs on the same 10-month standard / 6-month priority framework. S25: Drug Applications — FDA

510(k) — Premarket Notification

The clearance pathway for medical devices that are substantially equivalent to a predicate device. Not the pathway a sponsor would use for an investigational peptide therapeutic; included here for completeness because the term appears in device and combination-product coverage. S26: Premarket Notification 510(k) — FDA

Review framework

PDUFA VII — Prescription Drug User Fee Act reauthorization (FY 2023–2027)

The current user-fee framework. Sets action-goal timelines for agency review of original BLAs and NME NDAs: 10 months standard, 6 months priority, both measured from the 60-day filing date. These are performance goals for 90% of submissions, not approval guarantees. S04: PDUFA VII performance goals, section I.A.1, printed page 4

60-day filing date

The day FDA accepts the application for substantive review. PDUFA action goals count from this date, not from the date the sponsor mailed the submission. The 60-day period itself is administrative (does the submission meet filing requirements?). Acceptance is a separate event from approval.

Standard review

The default review pathway. 10-month PDUFA action goal for original BLAs/NME NDAs. Most new biologics are reviewed under standard review unless they qualify for a designated expedited pathway.

Priority review

An FDA designation, granted at the agency’s discretion, that shortens the action goal to 6 months for original BLAs/NME NDAs. Priority review is a process designation, not a label for the drug’s eventual approval or commercial importance. S05: Priority Review — FDA

Breakthrough therapy

An FDA designation for drugs intended to treat a serious condition where preliminary clinical evidence indicates substantial improvement on a clinically significant endpoint. A breakthrough designation is not approval, not the same as priority review, and not the same as accelerated approval. S27: Breakthrough Therapy — FDA

Fast track

An FDA process designation for drugs that treat serious conditions and fill an unmet medical need. Facilitates earlier and more frequent FDA-sponsor communication. Distinct from breakthrough, priority review, and accelerated approval. S28: Fast Track — FDA

Accelerated approval

An FDA approval pathway that allows approval based on a surrogate or intermediate clinical endpoint that is reasonably likely to predict clinical benefit, for drugs treating serious conditions. Post-marketing confirmatory trials are typically required. Not the same as expedited review designation. S29: Accelerated Approval Program — FDA

Review outcomes

Approval

A formal FDA determination that a drug is safe and effective for its proposed use, with labeling that defines indications, dosing, and other conditions of use. After approval, the sponsor may market the drug for the approved indication, subject to other applicable laws.

Complete Response Letter (CRL)

A written FDA response informing a sponsor that the review cycle is complete but the application cannot be approved in its current form. The letter describes the deficiencies. The sponsor may resubmit with additional information, withdraw, or request a meeting.

Refuse to File (RTF)

An FDA decision during the 60-day administrative filing period that the submission is not sufficiently complete to permit substantive review. The sponsor typically must refile. An RTF is not a judgment on the underlying science.

After approval (if granted)

REMS — Risk Evaluation and Mitigation Strategies

FDA-required safety monitoring or use-restriction programs that some approved drugs carry. A REMS can affect prescribing, dispensing, or patient monitoring requirements. Not all approved drugs have a REMS. S30: Risk Evaluation and Mitigation Strategies (REMS) — FDA

Post-marketing requirements (PMRs) and commitments (PMCs)

Studies or trials that an approved drug sponsor is required or commits to conduct after approval, often to gather additional safety, efficacy, or use information. Listed on the FDA website.

Advisory committee

An independent panel of experts convened by FDA to provide advice on a specific application or scientific issue. The committee votes and the FDA considers—but is not bound by—the vote. Advisory committee meetings for retatrutide have not been scheduled in the sources reviewed here.

What this glossary is not

This glossary does not predict any designation, date, or decision for retatrutide. It does not describe the sponsor’s commercial or pricing plans, nor does it address insurance coverage or pharmacy benefit design. Those are separate questions answered by separate documents, with separate caveats.