The 3Rs framework - Replacement, Reduction, Refinement - guides efforts to improve animal welfare in pharmaceutical and biomedical research, with significant recent progress.
Progress on the 3Rs in pharmaceutical research has been substantial over the past two decades, but significant animal use continues and further advances are urgently needed. Replacement technologies such as organ-on-a-chip and sophisticated in vitro models are increasingly validated for specific applications but cannot yet fully substitute animal research for complex systemic questions. The most impactful near-term advances combine improved refinement - reducing suffering in research that cannot yet be replaced - with strategic investment in replacement technology validation and regulatory acceptance. Engaging regulators to accept non-animal models for specific safety assessments is a critical bottleneck that requires sustained effort from the research, industry, and welfare communities.