Achievements and Challenges in Anti-Doping Research.

The most important element in achieving athlete compliance with anti-doping rules is the certainty of detection. Thus, scientific research plays a mission critical role in achieving clean competition. Many factors contribute to the advances in detection. Incremental advances in the ability to detect prohibited substances and methods, and identification of long-lived metabolites continue to lengthen detection windows. While the athlete biological passport hematological and steroidal modules hold great promise, experience shows that new research is needed to improve the sensitivity and specificity of the approach for current doping techniques. Indirect detection strategies using biomarkers or transcriptomic techniques have been increasingly investigated. The incorporation of more cost-effective sampling strategies using dried blood and plasma spots, oral fluid, and breath analysis show great promise toward increasing the number of tests while remaining within testing budget constraints. Despite the importance of research to ensuring rule compliance, a major challenge for anti-doping research is achieving and maintaining sufficient funding in the reality of the myriad of new substances introduced for disease treatment but abused for performance enhancement. In addition, obtaining metabolism and population reference range data, particularly for new drugs or designer drugs that have not obtained approval for administration to human subjects, remains a significant problem. Nevertheless, research continues to contribute important data to support anti-doping efforts.