Usage Examples
- The PDUFA date passed with a Complete Response Letter, not an approval.
- Every deficiency in the CRL needs a named owner before we scope the resubmission.
- The CRL is CMC-only, so no new clinical work is triggered.
What is Complete Response Letter (CRL)?
Complete Response Letter is the FDA action letter that closes a review cycle without approval, describing every deficiency the agency identified that a sponsor must resolve before an NDA, ANDA, or BLA can be approved.
A Complete Response Letter exists to deliver FDA's entire verdict on a review cycle in one document. The rule behind it, codified at 21 CFR 314.110 for drugs and 21 CFR 601.3 for biologics and published at 73 FR 39611 on July 10, 2008, requires the letter to describe all of the specific deficiencies the agency has identified rather than release them across successive rounds.
A Complete Response Letter covers original NDAs, ANDAs, BLAs, and their supplements. FDA issues one for the grounds set out in 21 CFR 314.125 or 314.127, and the letter must describe all of the specific deficiencies identified. A Complete Response Letter is not a refusal to file and not a final denial of approval; the application stays alive until the applicant resubmits, withdraws, or requests a hearing.
A Complete Response Letter is worked in practice as a deficiency-by-deficiency response package. The sponsor assigns each cited item an owner, decides whether the fix needs new data or only argument, and resubmits addressing all deficiencies. Complete Response Letters are no longer private documents: FDA publishes them through openFDA, including letters issued in 2026, so the deficiency language is readable by competitors and investors.
Not to be confused with
- Refuse to File letter
- a refuse to file ends a submission before substantive review because the application is incomplete on its face. A Complete Response Letter is issued only after FDA has completed its review of the data submitted.
- PDUFA date
- the PDUFA date is FDA's goal date for acting on an application, and a Complete Response Letter is one of the actions that can land on it. Hitting the PDUFA date says nothing about whether the application was approved.
- Information Request or Discipline Review letter
- these arrive mid-cycle, ask for clarification, and leave the review running. A Complete Response Letter closes the cycle and holds the review period open until the applicant takes one of three actions.
- Withdrawal of approval
- withdrawal removes an approval that already exists. A Complete Response Letter is issued to an application that has never been approved, so there is nothing to withdraw except the application itself.
The obligations attach to the applicant the moment the letter is issued.
What you must do
- 1Treat the Complete Response Letter as the full deficiency set, because FDA must describe all of the specific deficiencies it has identified in the application21 CFR 314.110(a)(1)
- 2Confirm the letter is a complete response, issued because FDA determined it will not approve the application in its present form for a reason given in § 314.125 or § 314.12721 CFR 314.110(a)
- 3Take exactly one of three actions: resubmit addressing all deficiencies identified in the letter, withdraw without prejudice to a subsequent submission, or request an opportunity for a hearing21 CFR 314.110(b)
- 4Act before the one-year mark, since the review period stays extended until the applicant acts and FDA may treat inaction within 1 year after issuance as a request to withdraw21 CFR 314.110(c)
- 5For a BLA or BLA supplement, run the equivalent biologics provision, under which FDA will when possible recommend actions that would place the application in condition for approval21 CFR 601.3(a)
Common mistakes
Answering only the deficiencies the team judges material
the regulation requires a resubmission that addresses all deficiencies identified in the complete response letter, not a filtered subset. Leaving items unanswered because they look minor or arguable produces a second Complete Response Letter and a second full review cycle.
Reading the letter as a complete picture of FDA's concerns
FDA may issue a complete response letter without first conducting required inspections, testing submitted product lots, or reviewing proposed product labeling when the submitted data are inadequate for approval. Silence on facilities or labeling is not clearance; those reviews can still bite on resubmission.
Assuming the Complete Response Letter stays confidential
FDA now publishes Complete Response Letters through openFDA, including letters issued in 2026. Deficiency language written for a reviewer becomes public reading for competitors, investors, and reporters, so the resubmission plan and the disclosure plan have to be built at the same time.
When This Matters
- The PDUFA date passed with a Complete Response Letter, not an approval.
- Every deficiency in the CRL needs a named owner before we scope the resubmission.
- The CRL is CMC-only, so no new clinical work is triggered.
Frequently Asked Questions
No. A Complete Response Letter is not a final denial; it ends the current review cycle and states what must be fixed. FDA issues a CRL when it will not approve the application in its present form, and when possible it recommends actions that would place the application in condition for approval.
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