15.08 - Organometallic Receptors and Conjugates With Biomolecules in Bioorganometallic Chemistry

A few organometallic drug candidates reached clinical development stages, but showed either adverse effects or lacked efficacy. These clinical studies indicated the importance of an efficient drug accumulation at the site of intervention and of detailed information about their modes of action and probable targets, as well as off-targets, to address safety aspects. The implementation of these factors already in early stages of drug development might be worthwhile. This chapter discusses comprehensive systems-based techniques to elucidate targets and molecular modes of action of organometallics, especially by metalloproteomics, as well as organometallic bioconjugation strategies to modulate their in vitro/in vivo accumulation and execute additional therapeutic effects. Analytical strategies are also highlighted, which are employed to assess organometal accumulation and distribution. Combining organometallic payloads possessing molecularly defined mechanisms of action with their selective accumulation at target sites by bioconjugation may improve the chances of organometallic drug candidates in clinical studies and may even guide patient selection or stratification. The field has progressed to a level of sophistication that will allow the rational design of organometallic bioconjugates with molecularly defined biological effects and synergistic properties of the bioconjugate in the near future that are not accessible by their individual components.