The Association of the British Pharmaceutical Industry (ABPI) has published a review of the effect of the full implementation of the Windsor Agreement for drug approval. The ABPI observes that the Windsor Framework introduces a two-category system for medicines in the UK from 1 January 2025, with Category 1 medicines becoming UK national licences regulated by the Medicines and Healthcare products Regulatory Agency (MHRA), and Category 2 medicines remaining subject to certain EU requirements. The APBI deems this reclassification complex due to potential regulatory divergence over time, especially for companies with diverse portfolios. Also, while many changes do not apply to existing products, the ABPI notes that, from 2025, medicines will require ‘UK Only’ labelling to prevent inadvertent flow to the EU. The ABPI and others advocated for the introduction of flexibilities to support the transition, including early release of ‘UK only’ labelled products to the UK market (excluding Northern Ireland), updating products through procedures that delay parts of the process by 12 months to ease regulatory burden, and completing labelling updates through UK-licensed repacking sites. The MHRA is updating guidance with trade associations’ support, and the ABPI continues to assist member companies.