Meeting report of the second European biotransformation workshop

Challenges and opportunities in the field of biotransformation were presented and discussed at the 2nd European Biotransformation workshop which was conducted virtually in collaboration with the DMDG on November 24/25, 2021. Here we summarise the presentations and discussions from this workshop.The following topics were covered:Regulatory requirements and biotransformation studies for antibody drug conjugates (ADCs) and antisense oligonucleotides (ASOs).Solutions for mass spectral data processing of peptides and oligonucleotides.Future outsourcing needs in biotransformation for new modalities.Established quantitative and qualitative workflows for metabolite identification.New in vitro systems to study new chemical entities (NCEs) with low metabolic turnover.New strategies on the timing of the human ADME (absorption, distribution, metabolism, excretion) study and to investigate the impact of human microbiome on drug development.