Free tool
Complete Response Letter search
Search every CRL FDA has published, including the full letter text. Each result shows FDA's own deficiency headings, so you can see at a glance whether a letter turned on the facility, the product or the clinical data.
Why the deficiency tags are the useful part
Every CRL is organised under FDA's own ALL-CAPS section headings. Most of them are boilerplate: PRESCRIBING INFORMATION appears in about 85% of letters, SAFETY UPDATE in about 89%. Searching the text for "labeling" finds it in nearly every letter and tells you nothing.
The tags here hide those standing sections and show only the ones that vary, which is where the letter's actual reason lives. Across the published corpus, manufacturing headings appear about three times as often as clinical ones.
We wrote up what the whole corpus says in this analysis, and the background on what a CRL is and what follows one is in the glossary.
Frequently asked questions
- What is a Complete Response Letter?
- FDA's decision not to approve an application in its present form, issued under 21 CFR 314.110. It lists the deficiencies the sponsor must address before the application can be approved.
- Are FDA Complete Response Letters public?
- Increasingly. FDA began publishing them in 2025, starting with roughly 200 letters and adding more since, with a stated commitment to publish them promptly after issuance.
- How many CRLs are published?
- The openFDA transparency dataset holds several hundred Complete Response Letters, issued between 2002 and the present. This tool searches all of them, including the full letter text.
- What do the deficiency tags mean?
- They are FDA's own section headings from inside each letter, such as FACILITY INSPECTIONS or PRODUCT QUALITY. Standing sections that appear in nearly every letter, like PRESCRIBING INFORMATION, are hidden so the meaningful ones stand out.
- Can I search the text of the letters?
- Yes. The first field searches the full letter body, so you can find every letter mentioning aseptic processing, stability or a specific impurity.
- Is this data official?
- It comes directly from FDA's openFDA transparency API, and each result links to the application's Drugs@FDA record. The letters are OCR'd from scanned PDFs, so some fields are imperfect.
Respond to one against your own record
Arca reads the published letters alongside your dossier and your prior FDA correspondence, and drafts a point-by-point response with every claim traced to the document it came from.