On the second of March 2021, the Section Pharmaceutical Toxicology of the NVT held its first online Symposium entitled “Challenges in vaccines development during the COVID-19 pandemic”. The exciting 2.5-hour program was led by national experts providing an overview on the history and strategies of the development of (COVID) vaccines. The experts gave insights in the assessment of COVID vaccines, including the usefulness and necessity of animal studies, clinical trial design and endpoints, (long term) side effects and vaccination during pregnancy. Further, the audience gained insights in the importance and challenges of COVID related communication. This was followed by an interesting Q&A session. Sixty six persons, 86% NVT members from which 40% were Pharmaceutical Section members were registered. Presentations can be found in the members-only section of the NVT website.