A UK-led initiative aims to move drug development away from traditional animal testing by using human-tissue–based models, such as organoids and stem cell systems, complemented by AI, bioengineering, and clinical research to better predict patient responses before clinical trials.

The program brings together partners including the Wellcome Sanger Institute, MRC-LMB, and Royal Papworth Hospital NHS Foundation Trust, coordinating activities across Cambridge and the wider UK.

Its goal is to shorten development timelines and costs while enabling more effective, personalised therapies through human-derived models.

The UK context features a continuing reduction in animal testing, with about 2.54 million procedures recorded in 2025, down from 2024, aligning with the Replacing Animals in Science Strategy and AI for Science Strategy.

In Britain, the 2025 animal-testing figure mainly involved mice, rats, fish, and birds, with only about 1% involving protected species, continuing a downward trend since 2024.

The government’s broader plan includes the Life Sciences Sector Plan, two-phase Contracts for Innovation competition, and MHRA’s 2026 move to review non-animal data earlier in regulatory processes.

While the aim is to shift toward human-based models, some animal testing may still be necessary for certain issues.

Historically, over 90% of drugs that pass animal testing fail in human trials, underscoring regulators’ push toward alternative methods where feasible.

The initiative emphasizes reducing animal testing due to ethical and scientific criticisms, noting the high failure rate in human trials despite animal success.

Current organoid programs acknowledge limitations in fully replicating circulatory, immune, or multi-organ interactions, and these models are intended to supplement rather than replace animal data, with ongoing validation.

Phase one of a two-phase competition seeks to deliver validated non-animal pharmacokinetic and cardiovascular safety assays, with phase two advancing the most promising projects toward real-world use.

The effort aligns with the UK’s Replacing Animals in Science Strategy and mirrors parallel moves in the US, where the FDA is promoting non-animal data in regulatory submissions.