A detailed explainer laid out why preclinical-to-clinical translation remains fragile and tied current efforts to regulatory plans to reduce animal reliance. The report noted that more than 90% of drug candidates fail to reach final approval, pointing to inadequate efficacy and unexpected toxicity, with animal models cited as a key limitation when they do not recapitulate human biology and patient diversity. It further references an FDA roadmap released in 2025 and a 2022 FDA Modernization Act 2.0 mandate for phasing out animal testing for new drug evaluations. For biopharma, the piece situates translational bottlenecks within evolving expectations for data packages, pushing developers toward more predictive models and human-relevant systems for Phase 1 readiness.