The UK implemented the biggest overhaul of clinical trials rules in about 20 years, with new regulations taking effect April 28. The update aims to reduce approval timelines and introduces a lower-risk category designed for automatic assessment within 14 days. A central change is the Combined Review process, under which sponsors can submit a single application that routes regulatory review through the Medicines and Healthcare products Regulatory Agency and ethics review through the Health Research Authority. Sponsors are expected to see faster routing for eligible studies, with the goal of cutting administrative delay while preserving oversight across risk tiers.