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FDA compliance

Insights on FDA inspections, compliance strategy, and regulatory intelligence from the Atlas team.

Where to Find FDA 483 Reports (and How to Read One)
FeaturedRegulatory Intelligence

Where to Find FDA 483 Reports (and How to Read One)

There are three routes to an FDA Form 483: FDA's FOIA electronic reading room, a FOIA request, or a searchable database. This guide compares them on coverage, wait time and search, then explains how to read a 483 once you have it, with three recent examples.

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Editor’s Picks

Preparing for FDA Pre-Approval Inspections: A Practical Guide
Inspection Readiness

Preparing for FDA Pre-Approval Inspections: A Practical Guide

FDA Inspection Classifications: VAI, NAI, and OAI Explained
Regulatory Intelligence

NAI, VAI, OAI: What Each FDA Inspection Classification Means

Preparing for FDA QSIT Inspections: What to Expect
Inspection Readiness

Preparing for FDA QSIT Inspections: What to Expect

How to Navigate the FDA Warning Letters Database Successfully
Regulatory Intelligence

FDA Warning Letter Database: How to Search It and Trace a Letter to Its 483

510(k) submission guide: the path from predicate to clearance and what FDA inspects after
Regulatory Intelligence

510(k) submission guide: what a 510(k) is, how FDA reviews it, and what inspectors check after clearance

A 510(k) is the premarket notification a device maker files with FDA to show a new device is substantially equivalent to a legally marketed predicate. This guide covers who must submit, the exemptions, Traditional, Special and Abbreviated 510(k)s, eSTAR, acceptance review and Additional Information holds, the 90 FDA day decision goal, how 510(k) compares with De Novo and PMA, when a change to a cleared device needs a new 510(k), and what Atlas data on 389 device Form 483s from 2026 shows about the design changes inspectors check after clearance.

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FDA combination products: the three types, primary mode of action and the cGMP rules in 21 CFR Part 4
Regulatory Intelligence

Combination products: the FDA definition, PMOA and the Part 4 cGMP rules

A combination product combines a drug, device or biological product into one product, one package or a cross-labeled pair. This guide covers the FDA definition in 21 CFR 3.2(e), the three types with examples, how primary mode of action decides the lead center, the Request for Designation, the 21 CFR Part 4 cGMP options as rewritten for the QMSR, postmarketing safety reporting under Part 4 subpart B, and what Atlas found in 193 Form 483s issued to 15 combination product makers.

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FDA foreign inspections: Form 483s issued outside the US by country, 2025 and 2026
Regulatory Intelligence

FDA foreign inspections in 2026: unannounced visits, the refusal rule, and the Form 483s by country

FDA inspects about 3,000 foreign facilities a year and now arrives at most Indian sites without notice. This guide covers the legal basis, what refusing or limiting an inspection triggers, 704(a)(4) records requests and Import Alert 66-79, and Atlas data on every Form 483 issued from January 2025 to July 2026 by country, including the regulations cited most often at Indian drug facilities.

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The four types of FDA inspections and how to tell them apart
Regulatory Intelligence

FDA inspection types: surveillance, for-cause, pre-approval and follow-up

FDA runs four types of inspections: surveillance, for-cause, application-based (pre-approval and pre-license) and follow-up. This guide explains what triggers each, how FDA picks sites for routine inspections, what a records request in lieu of inspection is, the day-of sequence from Form 482 to the EIR, and what 2,533 Form 483s issued in 2026 show about inspection team size and observation counts.

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FDA Investigations Operations Manual (IOM): what investigators follow from arrival to close-out
Regulatory Intelligence

FDA IOM: what the Investigations Operations Manual tells investigators, and what it tells you

The Investigations Operations Manual (IOM) is the primary operational reference for FDA investigators. This guide covers the 2026 edition, its ten chapters, the Chapter 5 sections an inspected firm should read (credentials, Form FDA 482, refusals, photographs, samples, the Form 483 close-out and the EIR), how the IOM differs from the Compliance Program Guidance Manual and the Regulatory Procedures Manual, and what Atlas data show about the investigators who apply it.

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FDA untitled letter explained: where it sits between a Form 483 and a warning letter
Regulatory Intelligence

FDA Untitled Letters: What They Are, Who Sends Them and What Follows

An FDA untitled letter is an advisory letter for violations that do not meet the threshold for a warning letter. This guide covers how the Regulatory Procedures Manual separates the two, which FDA offices send untitled letters, the 15 working day response OPDP asks for, how many OPDP letters FDA has posted each year since 2017, and how an untitled letter compares with a Form 483, a warning letter and a regulatory meeting.

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Medical device design controls under the QMSR: which design clauses FDA cited in 2026
Compliance

Medical device design controls under the QMSR: what FDA cites in 2026

Medical device design controls are the documented steps that turn user needs into a verified, validated device design. Since February 2, 2026, FDA enforces them through the QMSR and ISO 13485:2016 clause 7.3 instead of 21 CFR 820.30. This guide maps the old paragraphs to the new clauses, explains verification versus validation and the ISO 14971 risk link, covers what investigators ask for under Compliance Program 7382.850, and uses Atlas data on 389 device Form 483s from 2026 to show which design clauses FDA cites most.

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Computerized system validation: OQ audit trail tests inspectors check
Compliance

Computerized system validation: OQ audit trail tests for life sciences

Computerized system validation is the documented, risk-based evidence that a regulated computer system works as intended and keeps its data trustworthy. This guide covers the expectations in FDA's CSA guidance, Part 11, EMA and ICH E6(R3), a seven-step lifecycle, concrete OQ audit trail test cases, vendor and periodic review controls, and Atlas data on how often FDA cites computerized systems and data integrity.

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FDA 483 vs warning letter: the 15 working day response windows and what 4,584 Form 483s from 2025 show
Regulatory Intelligence

FDA 483 vs warning letter: who gets 15 working days to respond?

A Form FDA 483 is the investigator's list of observations at the close of an inspection. A warning letter is a formal advisory FDA issues later, after review, when it judges violations significant. This guide explains the 15 business day response window for each, how FDA escalates and closes out warning letters, what Atlas data on 4,584 Form 483s from 2025 shows, and how to write a response that survives verification.

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