U.S. EPA reinstates 2035 target to reduce or eliminate animal testing

The U.S. Environmental Protection Agency (EPA) recently reinstated its commitment to phase out mammalian animal testing by 2035. This action restores the agency’s earlier policy direction from 2019, which had been halted in 2024 when the prior administration withdrew the deadlines over feasibility concerns. With the reinstatement, EPA signals a renewed long term strategy to reduce reliance on vertebrate testing and expand the use of modern non animal methodologies.

Initial policy and subsequent reversal

The original 2035 deadline was established in 2019 under Administrator Andrew Wheeler, setting a clear goal to eliminate mammalian toxicity testing and build national capacity for non animal approaches. In 2024, however, the subsequent administration canceled the phase out timelines, opting for a more flexible approach that slowed progress toward alternative test development.

EPA’s 2026 announcement reverses that course. Administrator Lee Zeldin emphasized recommitting to the “historic goal” and accelerating the scientific development needed to meet it.

Key elements of the reinstated policy

1. Reaffirmed 2035 phase out deadline

EPA is once again enforcing the 2035 target to eliminate mammalian testing “wherever possible,” while recognizing that limited animal testing may remain necessary for statutory requirements.

2. Expansion and encouragement of alternative methods

The agency will encourage – not mandate – the use of in vitro, in silico, and other new approach methodologies (NAMs) that satisfy regulatory standards. FDA and NIH are also moving in this direction, further strengthening cross agency alignment.

3. Collaboration with advocacy and scientific organizations

A major component of the reinstatement involves collaboration with NGOs, scientific groups, and federal partners.

4. Investment in scientific modernization

EPA will continue prioritizing the development and validation of non-animal test methods, including computational modeling and human cell based assays.

Industry implications

Regulated entities should anticipate increased expectations for alternative data generation over the coming decade. Although animal testing is still required in limited circumstances, EPA’s long term direction will influence test planning strategies, data generation investments, and regulatory submission approaches.

How Sagentia Regulatory can help

Sagentia Regulatory (formerly TSG Consulting) can help you adapt to EPA’s reinstated policy direction. Our team can assist with:

• Evaluating how the 2035 target influences TSCA, FIFRA, and related regulatory obligations
• Assessing the suitability of NAMs and determining when they may meet EPA expectations
• Designing data generation strategies that minimize animal use
• Reviewing and preparing submissions incorporating NAM based evidence
• Advising on emerging toxicology strategies aligned with federal modernization efforts