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21 CFR Part 11 · FDA

Part 11 meets machine learning: what the US rules say about AI

There is no new Part 11 for artificial intelligence. There is a 1997 regulation that already applies, a credibility framework for AI models, and a final guidance on software assurance. Together they tell you most of what you need.

Kestrel Life SciencesOctober 20268 min readStatus at 9 October 2026: Part 11 unchanged since 1997. AI credibility guidance in draft (January 2025). CSA guidance final (September 2025, revised February 2026).

Ask around and you will hear about "the new Part 11 rules for AI". They do not exist. 21 CFR Part 11 has not been amended to address artificial intelligence, and FDA has not proposed that it should be. What has changed is the guidance around it, and the questions inspectors ask when a model is involved in a GMP record or decision.

Part 11 already applies to your model

If an AI model creates, modifies or relies on electronic records that the predicate rules require you to keep, Part 11 applies to the system it runs in. The familiar controls carry straight across: validation for accuracy, reliability and consistent intended performance; secure, computer-generated, time-stamped audit trails; authority checks; and electronic signatures that are linked to their records.

What AI adds is a harder question under "consistent intended performance". A model that drifts, retrains or behaves differently on unfamiliar inputs strains that phrase in a way a fixed calculation never did.

The credibility framework

In January 2025 FDA published draft guidance, Considerations for the Use of Artificial Intelligence to Support Regulatory Decision-Making for Drug and Biological Products. Its core is a seven-step, risk-based framework for establishing that a model is credible for a specific context of use. The guidance covers the drug lifecycle broadly, and it includes manufacturing in its examples.

FDA's credibility framework, in one picture 1Define the question of interest2Define the context of use3Assess model risk4Plan the credibility assessment5Execute the plan6Document results and deviations7Decide: adequate for the context of use? STEP 3: MODEL RISKMediumHighHighLowMediumHighLowLowMedium HighLow Decision consequence LowHigh Model influence Matrix shown schematically; the January 2025 draft guidance describes low, medium and high levels for each axis.
Figure 1. The seven steps of FDA's draft credibility framework and the model risk matrix behind step 3.

Model risk combines two things: model influence, how much the AI output contributes to the decision relative to other evidence, and decision consequence, how bad an incorrect decision would be. A model that only prioritises samples for human review sits in a very different place from one whose output alone releases a batch.

Computer Software Assurance: the companion piece

FDA finalised Computer Software Assurance for Production and Quality System Software on 24 September 2025 and issued a revised version in February 2026 aligned with the device Quality Management System Regulation. CSA's message is that assurance effort should follow risk: concentrate rigorous, scripted testing where a failure would affect product quality or patient safety, and use lighter, unscripted methods and supplier evidence elsewhere. It is a device-centre guidance, but its thinking is being read widely across pharma.

QuestionEU: draft Annex 22US: FDA draft AI guidance
Starting pointIntended useQuestion of interest and context of use
Risk basisCritical versus non-critical GMP applicationModel influence × decision consequence
Model typesStatic, deterministic models for critical useNot restricted by type; credibility must be shown
Test dataIndependent of training data, representativePart of the credibility assessment plan
In useChange control, drift and input monitoring, human reviewLife-cycle maintenance and change reporting

Kestrel view

Build one evidence package that satisfies both: an intended use that doubles as a context of use, a risk rationale that speaks both languages, and a test set you can defend to either inspector.

Practical steps for a model that touches GMP records

  1. Confirm which predicate-rule records the model creates, changes or relies on.
  2. Make the model version, configuration and input data part of the audit trail.
  3. Rate model influence and decision consequence, and document the result.
  4. Scale the assurance effort to that rating, in the spirit of CSA.
  5. Define the trigger for revalidation: retraining, new inputs, or a drop in monitored performance.

Working through any of this on a live system?

Tell us the system and the regulation. We will come back to you within one working day.