FDA Reports Its First Year of Work to Reduce Animal Testing

From the 2025 Roadmap to an Implementation Report

FDA published a first-year progress report on 20 April 2026 following its 2025 roadmap for reducing animal testing in drug development. The report organizes activity around internal coordination, method qualification, transparency, regulatory guidance and international collaboration. Its examples show several ways that human-relevant evidence can enter a safety program or a drug-development-tool assessment.

The report describes the initiatives as connected parts of an implementation strategy. New review structures provide access to scientific expertise; published guidance explains proposed evidence expectations; databases make existing experience easier to find; and qualification programs provide a route for assessing tools for defined applications. The status of each activity is an important part of that account.

Coordination and the Qualification Pathway

The Center for Drug Evaluation and Research (CDER) established a NAMs Coordinating Committee in April 2025, and an FDA-wide workgroup followed in January 2026. The report also describes a concept of operations for a NAMs Integrated Review Team to be piloted in 2026. These arrangements aim to bring together expertise when a computational or human-cell method crosses therapeutic-area and disciplinary boundaries.

The Innovative Science and Technology Approaches for New Drugs (ISTAND) pilot became a permanent program on 31 July 2025. The report records eight submissions accepted during the pilot and more than 16 active submissions at different qualification stages in early 2026. A liver microphysiological system had advanced to final qualification stages, while other submissions and development efforts addressed liver injury, kidney toxicity, reproductive toxicity and arrhythmia risk.

An August 2025 memorandum between FDA and the National Institutes of Health (NIH) provides a collaboration framework through the Complement Animal Research In Experimentation (Complement-ARIE) program. It links technology development, data infrastructure and validation networks with regulatory-science needs.

Making Evidence Expectations Easier to Find

The report highlights FDA’s March 2026 general NAMs draft guidance and its four principles: context of use, human biological relevance, technical characterization and fitness for purpose. The principles are intended to help developers define the evidence needed for a particular regulatory question.

A searchable CDER database launched in October 2025 lists contexts in which streamlined nonclinical programs and acceptable NAMs have been used. It makes examples involving reduced animal numbers, fewer species or alternative evidence more accessible. The report also discusses analyses of prior NAM submissions and technical research on measuring liver-injury biomarkers in liver-chip systems.

Guidance and a Qualified AI Tool

One central example is FDA’s December 2025 draft guidance on monoclonal antibodies. It proposes using three-month studies together with a weight-of-evidence risk assessment to support reduced reliance on six-month nonhuman-primate studies, with NAMs contributing where appropriate. The report presents the draft as a major implementation step while the scientific justification remains tied to the product and proposed program.

The agency qualified AIM-NASH in December 2025 for an AI-assisted liver-biopsy assessment role in metabolic dysfunction-associated steatohepatitis trials. This example concerns support for pathology scoring within a specified drug-development use. The report also notes the March 2026 update on pyrogen and endotoxin testing, which provides flexibility to move from animal-derived reagents to recombinant alternatives.

International Work and the Continuing Evidence Base

FDA and NIH convened an international workshop on 7 July 2025 with participation from European, Japanese, Australian and other regulatory partners. Discussions covered scientific advances and approaches to implementing alternative methods. The report places this alignment alongside domestic work because developers often need an evidence strategy that can be discussed in more than one region.

Taken together, the recorded milestones show progress in the infrastructure surrounding NAMs as well as in guidance and individual tools. The report identifies some methods as qualified, others as under assessment and others as still being developed. Those distinct stages help explain where developers can draw on an established pathway and where additional evidence generation remains part of the work.