Atlas Blog

Expert-led insights on
FDA compliance

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

Cleaning validation FDA and EMA requirements, with 21 CFR 211.67 citation data
Regulatory Intelligence

Cleaning validation: FDA and EMA requirements, acceptance limits, and what 483s cite

What FDA and EMA require for cleaning validation: 21 CFR 211.67 and 211.182, FDA's 1993 inspection guide, ICH Q7 section 12.7, EU GMP Annex 15 and the EMA guideline on health-based exposure limits. Covers acceptance limits (HBEL/PDE, 1/1000 dose, 10 ppm), protocols, sampling, hold times and continued verification, with Atlas data on how often 211.67 appears on 2025 and 2026 human drug Form 483s.

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FDA quality agreements: what owners and contract facilities must each control
Regulatory Intelligence

FDA Quality Agreements: What the Guidance Requires and Where Contracts Fail

A quality agreement is the written document in which a drug owner and a contract facility assign each CGMP activity. This guide covers what FDA's November 2016 guidance says, whether a quality agreement is required, a section-by-section checklist, how it differs from a supply agreement, how often 2025 and 2026 human drug Form 483s cite the quality unit section 21 CFR 211.22, and where agreements fail.

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FDA quality metrics program: four practice areas and the CFR sections FDA cites for each
Regulatory Intelligence

The FDA quality metrics program in 2026: practice areas, QMM, and what Form 483s measure

What the FDA quality metrics program is, why reporting is still not required, the four practice areas FDA proposed in 2022 with their example metrics, how the program differs from CDER's voluntary Quality Management Maturity assessments, and which 21 CFR Part 211 sections FDA investigators cited in each practice area across 779 human drug Form 483s issued from January 2025 to June 2026.

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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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