Question 1

What's the difference between a deficiency letter and an AI letter?

Accepted Answer

A deficiency letter (sometimes called a hold letter) identifies specific gaps in your premarket submission that block clearance - usually missing or inadequate documentation tied to Section 524B, an incomplete SBOM, weak threat model, or insufficient penetration testing. An AI letter (Additional Information request) asks for clarification or additional evidence on items the reviewer believes are partially addressed but not fully demonstrated. The response strategy differs: deficiency letters require rebuilding artifacts and resubmitting through eSTAR, while AI letters often require targeted clarifications, supplemental analysis, or narrow retesting. We handle both - and we determine which path applies during the 48-hour gap analysis.

Question 2

What's the fastest you've turned around a deficiency response?

Accepted Answer

Our fastest reviewer-ready package was 11 days from engagement to filed response - a Class II connected wearable with an RTA citing inadequate Section 524B documentation. Typical turnaround is 3 to 6 weeks depending on the number of deficiency items, whether retesting is required, and how much of the original submission needs to be reconstructed. We deliver the gap analysis within 48 hours of receiving your letter, so within two business days you know exactly what the timeline and fixed fee will be - no extended scoping calls, no surprises.

Question 3

How do you prioritise which deficiency items to address first?

Accepted Answer

We triage in three tiers. First: items the reviewer flagged as critical or that block the rest of the submission - typically threat model gaps, missing SBOM, or Section 524B traceability failures, since these are foundational and other artifacts depend on them. Second: documentation gaps where the underlying work exists but isn't presented in a form the reviewer can audit - security architecture views, risk traceability matrices, eSTAR formatting. Third: supporting evidence such as additional pen test coverage, VEX updates, or postmarket plan refinements. This ordering minimises rework and helps the reviewer assess the response efficiently.

Question 4

What if FDA issues a second deficiency letter after our response?

Accepted Answer

We stay on the engagement at no additional cost until the deficiency is fully resolved. If FDA comes back with a second-round letter or AI request on items we addressed, we treat it as part of the original scope - diagnose the new finding within 24-hours, rebuild the affected sections, and refile. This is the deficiency-response form of our no-cost deficiency resolution commitment: the fixed fee covers resolution, not a single round-trip. Across 275+ devices, we have never had a final response rejected.

Question 5

How do you handle 510(k), De Novo, PMA, PDP, and HDE deficiencies differently?

Accepted Answer

The cybersecurity expectations are similar across pathways but the documentation depth, review clock, and reviewer scrutiny differ. 510(k) deficiencies usually focus on substantial-equivalence-relevant cyber items - threat model alignment to the predicate, SBOM completeness, pen test scope. De Novo deficiencies often probe novel risk arguments and security architecture justifications since there is no predicate. PMA deficiencies involve the deepest documentation, full design history file traceability, and frequently coordinate with non-cyber reviewers on risk control and human factors. IDE deficiencies (often appearing as a Clinical Hold under 21 CFR 812.42) focus on whether unresolved cybersecurity risks could expose study subjects to unreasonable risk - reviewers want to see the threat model, security risk assessment, and any clinical-environment compensating controls before enrolment can proceed. We tailor the response package to the pathway and the specific reviewer's prior comment patterns.

Question 6

Is the 48-hour gap analysis a paid deliverable or part of scoping?

Accepted Answer

It's the first paid deliverable of the engagement and becomes the foundation for the fixed-fee remediation work. Once you sign the engagement letter and share the FDA correspondence and the original submission package, a senior MedTech cybersecurity engineer maps every deficiency item to the specific FDA guidance section it references, identifies which artifacts need to be rebuilt versus updated, and estimates the remediation effort. You get a written gap analysis plus a fixed-fee quote for the full response package within two business days - so the 180-day clock isn't burning while you wait.

Question 7

What does the engagement cost and how is it priced?

Accepted Answer

Pricing is fixed-fee, scoped after the 48-hour gap analysis. Cost depends on the number of deficiency items, whether retesting (penetration test or specific component testing) is required, the original submission's documentation maturity, and the pathway (510(k), De Novo, or PMA). Typical engagements run from a low-five-figure scope for a clean, documentation-only response to mid-five-figures for responses involving full pen test retesting and threat model rebuilds. The fixed fee covers unlimited revisions and second-round response if FDA comes back - no hourly billing, no scope creep, no surprises after you sign.

Question 8

Can we use our own regulatory team to file the response, or do you handle filing too?

Accepted Answer

Either works. Most clients prefer that we deliver the complete reviewer-ready package - point-by-point response document, rebuilt artifacts, traceability matrix, eSTAR-formatted sections - and their internal regulatory affairs team handles the actual eSTAR upload and reviewer coordination. We can also coordinate directly with your filing consultant or RA contractor. If you want us to attend the response readout call with FDA (rare but offered), we can join as the cybersecurity subject matter expert. The deliverable format is the same regardless of who files.

Question 9

What information do you need from us to start the gap analysis?

Accepted Answer

Three things: the FDA correspondence (deficiency letter, AI request, or RTA notice in full), the original submission package or at minimum the cybersecurity sections that triggered the findings, and a brief technical summary of the device architecture if it isn't fully captured in the submission. A mutual NDA is signed before any device material is shared. Once we have these, the 48-hour gap analysis clock starts - and within two business days you have a written gap analysis, remediation plan, and fixed-fee quote.

Question 10

Do you handle deficiencies on AI/ML-specific items like PCCPs or training data provenance?

Accepted Answer

Yes. AI/ML deficiencies are increasingly common: missing or weak Predetermined Change Control Plans, inadequate adversarial robustness testing, gaps in training data provenance documentation, and insufficient transparency labeling under the 2025 draft guidance. Our response process extends the standard SPDF rebuild with MITRE ATLAS threat extension, GMLP-aligned model documentation, AAMI CR34971 risk controls, and adversarial test execution where the reviewer requested it. The 48-hour gap analysis identifies which AI-specific artifacts need to be rebuilt versus clarified.

Question 11

What happens if our 180-day clock has nearly expired or already lapsed?

Accepted Answer

If you have under 30 days remaining, we escalate immediately - engagement letter signed in 24 hours, gap analysis compressed where possible, and remediation work runs in parallel rather than sequentially. If the 180-day window has already lapsed, the path depends on FDA's specific notice: in most cases the submission moves to withdrawn status and we help you file a new submission with the cybersecurity package rebuilt to clear on the first round. We've handled both scenarios - the earlier you engage, the more options remain on the table.

Question 12

Will you deal directly with the FDA reviewer on our behalf?

Accepted Answer

We don't replace your regulatory affairs lead in formal FDA communications - that relationship belongs to the submission sponsor and your RA team. What we do provide is the cybersecurity subject matter expertise behind every reviewer interaction: drafting the technical content of response letters, preparing your team for any reviewer call (including likely follow-up questions), and (when invited by your RA team) joining a pre-submission or response readout call as the cybersecurity SME. The reviewer sees a unified team; you keep the official communication channel.

FDA Cybersecurity Deficiency Response48-Hour Gap Analysis, Reviewer-Ready Package.

How do you respond to an FDA cybersecurity deficiency letter?

From deficiency letter to response.

Letter arrives

Triage

Fix & retest

Response file

How much time do you actually have left?

Quiet phase

Burn rate climbs

Submission at risk

Revenue impact

How we help you respond to the FDA

Hold Letter Review & Analysis

Additional Information Requests

Threat Model Remediation

Penetration Testing & Retesting

Documentation Gap Analysis

Full Response Package Assembly

From hold letter to reviewer-ready submission.

Send Us Your Hold Letter

Gap Analysis & Strategy

Build the Evidence

Submit With Confidence

What FDA reviewers see in a weak response vs. ours.

Another deficiency round

Cleared on first response

Every deliverable in your deficiency response package

Don't let a deficiency letter delay your device any longer.

Real deficiency responses, real clearances

7 cybersecurity deficiencies cleared in 5 weeks

Refuse to Accept reversed in 11 days

12 AI requests answered in one round

The senior expert on your call oversees the work end to end.

Backed by MedTech leaders.

What a deficiency response engagement covers

Reviewer-ready deliverables in one engagement

Standards FDA deficiency response maps to

FDA Premarket Cybersecurity Guidance (Feb 3, 2026)

FD&C Act Cyber Device Requirements

Electronic Submission Template

Medical Device Security Risk Management

Medical Device Risk Management

Public premarket cybersecurity history

Section 524B(b) AI/ML deficiencies

Multi-Patient Harm view as recurring deficiency

Services mapped to the same standards as fda deficiency response

FDA Premarket Cybersecurity Package

SaMD Cybersecurity

PCCP Cybersecurity Services

Resources on this topic

Guides

Articles

Try the free tool first.

Deficiency Letter Triage

eSTAR Cyber Checklist

FDA Cyber Readiness Quiz

FDA deficiency response FAQs