Meeting report of the first European biotransformation workshop.

1. Challenges and opportunities in the field of biotransformation were presented and discussed at the 1st European Biotransformation workshop which was conducted virtually in collaboration with the DMDG 27 January 2021. Here we summarize the presentations and discussions from this workshop.The following topics were covered:2. Needs for radiolabel for IND filing versus quantitation without standards.3. Applications of cyclic ion mobility in the field of biotransformation.4. Computational predictions of xenobiotic metabolism.5. Future (outsourcing) needs in biotransformation.6. Genotoxicity risk assessment of metabolites and qualification of impurities using metabolite data.7. Regulatory aspects of MIST.