Nonclinical Testing Terminology
Key claim: FDA is rewriting certain drug-safety rules to say “nonclinical” instead of “animal” testing, so non-animal methods can be used without any new requirements.
Abstract
(Rule · Health and Human Services Department, Food and Drug Administration) 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.
[This finding represents 2 closely related documents issued 2026-09-22 (same source, same action). Related: fedreg:2026-19349]
Why this matters
The rule is a semantic update that formally opens the door for sponsors to satisfy drug-safety requirements using non-animal methods (organ-on-chip, in silico models, etc.) without changing what FDA requires. For patients and industry, nothing changes immediately, but it codifies a regulatory posture that treats non-animal testing as equivalent nonclinical evidence going forward.