Nonclinical Testing Terminology

Open for public comment until Dec. 7, 2026. Comment on Regulations.gov

What it does

The Food and Drug Administration (FDA, Agency, or we) is proposing to substitute references to "animal" tests or studies with "nonclinical" tests or studies, add a definition of the terms "nonclinical test" and "nonclinical study," and make other comparable or conforming amendments in certain safety and reporting sections of its regulations. The proposed rule would also substitute "nonclinical" for "preclinical" and "in vitro" for consistency in terminology. These proposed 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 proposed rule would add no new requirements.

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

What it would change

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

Before this

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

• Sept. 22, 2026 Direct final rule. Nonclinical Testing Terminology

What happens next and when

Either electronic or written comments on the proposed rule or its companion direct final rule must be submitted by December 7, 2026. If FDA receives any timely significant adverse comments on this proposed rule or the direct final rule with which this proposed rule is associated, we will publish a document in the Federal Register withdrawing the direct final rule within 30 days after the comment period ends, and we will then proceed to respond to comments under this proposed rule using the usual notice and comment procedures.

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