EVALUATION OF LONGITUDINAL STEROID PROFILING WITH THE ADAMS ADAPTIVE MODEL FOR DETECTION OF TRANSDERMAL, INTRAMUSCULAR, AND SUBCUTANEOUS TESTOSTERONE ADMINISTRATION.

The steroidal module of the Athlete Biological Passport (ABP) has been used since 2014 for the longitudinal monitoring of urinary testosterone and its metabolites in order to identify samples suspicious for the use of synthetic forms of Endogenous Anabolic Androgenic Steroids (EAAS). Samples identified by the module may then be confirmed by Isotope Ratio Mass Spectrometry (IRMS) to clearly establish the exogenous origin of testosterone and/or metabolites in the sample. To examine the detection capability of the steroidal ABP model, testosterone administration studies were performed with various doses and three routes of administration - transdermal, intramuscular and subcutaneous with fifteen subjects for each route of administration. Urine samples were collected before, during, and after administration and steroid profiles were analyzed using the steroidal ABP module in ADAMS. A subset of samples from each mode of administration was also analyzed by IRMS. The steroidal ABP module was more sensitive to testosterone use than population-based thresholds and with high dose administrations there was very good agreement between the IRMS results and samples flagged by the module. However, with low dose administration the ABP module was unable to identify samples where testosterone use was still detectable by IRMS analysis. The testosterone/ epitestosterone (T/E) ratio was the most diagnostic parameter for longitudinal monitoring with the exception of low testosterone excreters for whom the 5α-androstane-3α, 17β-diol/epitestosterone (5αAdiol/E) ratio may provide more sensitivity.