Exogenous T was detected with IRMS regardless of T/E elevation—high serum T indicative for IRMS. rhEPO was detected in urine for 72 h in ITP and CP, and Tasso showed less sensitivity than previous DBS devices tested.

ABSTRACT

Doping with testosterone (T) and erythropoietin (EPO) in low doses (micro-doping) is a challenge to detect. Here, we have investigated the ability to detect micro-doping of recombinant human (rhEPO) and testosterone (T) after administration of a single dose of subcutaneous Eporatio (15 IU/kg) and transdermal Testogel (100 mg) to healthy males. For rhEPO detection in urine, MAIIA EPO purification kits 3F6 (#1410) and 7D3 (#1460) were used for ITP and CP analyses, respectively, whereas kit 3F6 (#1430) was used for dried blood spots (Tasso). The sensitivity to detect rhEPO in Tasso was investigated and compared with previous detection results for Capitainer and Mitra. For T detection, the urinary and capillary serum steroid profile and IRMS analysis were performed. It was possible to detect administration of 15 IU/kg Eporatio with high sensitivity with our ITP method up to 72 h after administration, and the CP findings supported the ITP findings. Tasso provides less sensitivity in detecting Eporatio than Mitra and Capitainer. With IRMS, 100% of the samples analyzed were positive, also when not associated with elevated urinary T/E or 5αAdiol/E ratios. As an alternative, high systemic T levels aligned with positive IRMS results, highlighting the value of serum T as a complementary biomarker. Overall, the World Anti-Doping Agency ITP and CP methods employed today show good sensitivity towards detection of micro-dosing of rhEPO and T.