Analytical approaches in sports drug testing are continuously updated and expanded, exploiting new information on drug metabolism and disposition in humans as well as innovations in sample preparation and analysis, and also novel strategies focusing on marker-based test methods have been assessed, developed, and implemented. The resulting improved detection capability and retrospectivity of sports drug testing approaches has considerably limited the formerly available options of substances and methods of doping.
In order to implement new, emerging drugs into routine anti-doping tests, information on the metabolic fate of such substances is critical, and strategies that allow mimicking the human metabolism for test method development have thus become particularly relevant in preventive anti-doping research. One option successfully simulating drug administration and metabolism reactions has been established with organ-on-a-chip technologies, and first proof-of-concept results have demonstrated the utility of this methodology also for sports drug testing purposes.
This strategy certainly supports anti-doping efforts concerning lower molecular mass drugs and drug candidates. With the need to implement testing approaches regarding the illicit use of higher molecular mass analytes including peptide- or protein-based drugs as well as gene transfer, gene editing, and gene silencing interventions, the extent as to how organs-on-a-chip can help is still to be explored. Also here, first data suggest that in particular subcutaneous drug administrations can successfully be mimicked, opening an avenue towards drug metabolism and elimination studies.