Ep 47 | David Petrie-Dolphin: How Poultry Vaccines and Animal Health Products Get Approved

In this episode of the Poultry Network Podcast, Tom Woolman speaks with David Petrie-Dolphin of Drayton Animal Health about the behind-the-scenes work involved in bringing poultry vaccines, veterinary medicines and animal health products to market.David explains the role of a Contract Research Organisation, or CRO, and why pharmaceutical and animal health companies often use specialist external facilities to carry out regulated safety and efficacy studies. The conversation covers how studies move from early molecule testing through to animal safety work, controlled trials and real-world farm testing.They also discuss the strict regulatory environment around animal health research, including Home Office licensing, third-party auditing, GLP and GCPv standards, and the role of bodies such as the European Medicines Agency and the Veterinary Medicines Directorate. A key theme throughout the episode is animal welfare, with David explaining how welfare, ethics, acclimatisation, study design and the three Rs — replacement, reduction and refinement — shape every trial.Key topics coveredWhat a CRO doesDavid explains that Drayton Animal Health is a Contract Research Organisation carrying out animal safety and research work for veterinary medicines, vaccines, feed additives and related products.Why pharmaceutical companies use CROsRather than building and maintaining specialist facilities that may only be needed every few years, companies can work with CROs that run regulated studies day in, day out.What the research environment looks likeThe facilities are described as secure and highly controlled, but still farm-like in appearance and operation, reflecting the practical realities of livestock production.How vaccine and medicine approval worksDavid outlines the multi-stage process from early molecule testing to safety, efficacy, toxicology, absorption and withdrawal-period studies.Regulation and scrutinyThe episode covers the role of regulators, Home Office licensing, third-party audits and the need for data to be robust, repeatable and defensible.UK, European and global approvalsTom asks how Brexit has affected veterinary medicines regulation, and David explains that UK-generated data can still play a role in wider European and international approval processes.GLP, GCPv and ethical oversightDavid explains how Good Laboratory Practice and Good Clinical Practice Veterinary standards create consistent global benchmarks for research, while Animal Welfare Ethical Review Boards assess study design before work begins.The three Rs in farm animal researchThe discussion explores replacement, reduction and refinement, with particular attention to using the minimum number of animals needed while still producing statistically meaningful results.Controlled trials versus commercial farm trialsDavid explains why products are first tested in controlled CRO environments before moving into commercial field conditions, where farms, management systems and geography can all vary.Animal welfare in trialsThe conversation ends with a focus on welfare, including acclimatisation, stress reduction, careful handling, bespoke study design and rehoming animals where possible.