AINN & DEFICIENCY RESPONSE

The 180-day clock is already running.

An Additional Information letter freezes your submission, answer in time or start over. MSI gets your response FDA-ready in a fraction of the window, drafted with former reviewers in the language the agency is waiting to read.

Beat your deadline →
Clock running
Your response window
180 days
The moment that letter lands, the countdown starts, miss the deadline and the submission is withdrawn.

Decode the letter

Every deficiency is parsed and mapped to what FDA is really asking, with the guidance and precedent behind it surfaced alongside.

Priority access to reviewers

Former FDA CDRH reviewers work your response with you, not a ticket queue, not generic templates.

Built on real deficiency data

Semantic search across actual FDA deficiency letters means your response reflects what has closed findings like yours before.

ADDITIONAL INFORMATION LETTER Maps to 21 CFR 807.87(f) Prior deficiency precedent Every deficiency parsed and mapped to what FDA is really asking. YOUR RESPONSE WINDOW 142 days remaining Letter received You are here Deadline · day 180

Why teams do it

The clock is unforgiving

Respond well, within the window, or risk withdrawal and a restart. The letter sets the deadline; this is how you hit it.

A wrong answer buys another round

A vague or incomplete response earns another hold letter and another quarter lost. Answering precisely the first time is the whole game.

The bar is moving, and so is FDA

FDA is reviewing submissions with new tooling of its own, and the level of rigor that cleared a finding last year may not clear it now. Your response has to meet the standard the agency is applying today, not the one it used to.

How we work with your team

1

Bring us the letter

Upload the AINN or hold letter along with your submission package. No reformatting.

2

Map each deficiency

MSI breaks the letter into discrete findings and drafts structured responses, citing the relevant guidance and prior deficiency precedent.

3

Reviewers pressure-test it

Former FDA reviewers verify each response would actually close the finding, before it goes back to FDA.

What you get

Structured deficiency responses

AI-assisted drafting and tracking of regulatory correspondence, organized finding by finding so nothing in the letter goes unanswered.

Deficiency-letter intelligence

Semantic search across FDA guidance and real deficiency letters, with suggested queries, highlighting, and source attribution.

FDA Agent on call

Ask questions of FDA guidance and your own evidence in plain language while you draft, with answers you can trace back to source.

Tracked correspondence

Every response versioned and tracked, so nothing falls through the cracks between rounds of review.

Built on Enforcement Intelligence

Most responses guess at what FDA wants. MSI grounds yours in what FDA actually issues and accepts, built on proprietary data about what the agency is catching and requiring, by a team that includes former FDA CDRH reviewers and authors of the guidance itself. Automation for the draft, reviewers for the judgment.

Former FDA CDRH reviewers · AINN & hold letter response · 510(k) / De Novo / PMA · Deficiency-letter intelligence · Section 524B aligned

Don't answer a hold letter alone

One working session on your actual letter. The findings decoded, the response mapped, the people who've closed them before.

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