Nonclinical Testing Terminology

What it does

The Food and Drug Administration (FDA, Agency, or we) is issuing a direct final rule that substitutes references to "animal" tests or studies with "nonclinical" tests or studies, adds a definition of the terms "nonclinical test" and "nonclinical study," and makes other comparable or conforming amendments in certain safety and reporting sections of its regulations. The direct final rule also substitutes "nonclinical" for "preclinical" and "in vitro" for consistency in terminology. The Agency is issuing these amendments directly as a final rule because we believe they are noncontroversial changes in terminology that are not expected to affect industry practice and FDA anticipates no significant adverse comments. These amendments align with recent amendments to the Federal Food, Drug, and Cosmetic Act (FD&C Act) and the Public Health Service Act (PHS Act) and are intended to remove an emphasis, in certain places, on the use of animal testing as the only scientific methodology to assess the safety of a drug in the nonclinical setting. These changes may also foster the development and use of scientifically valid new testing methodologies, potentially improving predictive accuracy of product safety testing while replacing, reducing, or refining animal use. The rule adds no new requirements.

The Food and Drug Administration's summary, as published in the Federal Register.

What changed in the regulation

5 parts of Title 21 of the Code of Federal Regulations:

21 CFR 312, 21 CFR 314, 21 CFR 315, 21 CFR 361, 21 CFR 601

Compared with

The Food and Drug Administration has published 100 final rules in 2026 so far, compared with 68 in all of 2025.

Counted by the Tribune from Federal Register records since Jan. 1, 2025.

Before this

1 earlier Federal Register document under regulation identifier 0910-AJ27 since Jan. 1, 2025.

• Sept. 22, 2026 Proposed rule. Nonclinical Testing Terminology

What happens next and when

This rule is effective February 4, 2027. Either electronic or written comments on the direct final rule or its companion proposed rule must be submitted by December 7, 2026. If FDA receives no significant adverse comments within the specified comment period, the Agency intends to publish a document confirming the effective date of the direct final rule in the Federal Register within 30 days after the comment period on this direct final rule ends. If timely significant adverse comments are received, the Agency will publish a document in the Federal Register withdrawing this direct final rule within 30 days after the comment period on this direct final rule ends.

The agency's dates, word for word.

Check it yourself

• The document in the Federal Register
• Docket FDA-2026-N-5347 on Regulations.gov
• Title 21 on eCFR

The record as published

Source: the Federal Register (public domain). The document in the Federal Register