EPO and the athlete biological passport: Hematological results from a placebo-controlled, boosting and microdose EPO administration in male recreational athletes.

Hematological results in the context of the Athlete Biological Passport (ABP) from a placebo-controlled EPO administration study are provided here. Twelve participants administered eight subcutaneous boosting doses of epoetin alfa (at 40 IU/kg) over the course of 20 days. After a 10-day washout period, the same volunteers administered six microdoses (900 IU), intravenously, over 13 days. A blinded placebo cohort followed the same dosing pattern, administering saline instead of EPO. All participants supplemented with oral iron, daily, throughout the entirety of the study. In the EPO cohort, as expected, significant changes from baseline were identified in IRF, RET#, RET%, RDW, HCT, HGB, and RBC. No meaningful changes were identified in the placebo cohort population. From the ABP perspective, atypical passport findings (ATPF) were identified in 49% of the samples collected during the boosting and initial washout phases, and 24% of the samples during the microdosing and final washout phases. ATPFs from this cohort were flagged as late as Day 70, the final day of the study. Only a single ATPF was identified from all samples collected from the placebo cohort. ABPs from all volunteers in the study are provided as an avenue to visually convey differences in magnitude and timing of the hematological changes caused by EPO on the individual level. These data are expected to provide important content for Athlete Passport Management Units and ABP expert panels alike.

Growth hormone isoform testing in capillary dried blood spots: Results from single and multiple dose administration studies and large-scale field collections.

A multiphase study was designed to examine the detectability of human growth hormone (GH) use in capillary dried blood spots (DBS). First, 13 subjects self-injected a single, 2-mg dose of somatropin and collected capillary DBS samples for 24 h. Next, nine subjects self-injected 2-mg somatropin, six times over the course of 11 days; DBS were collected intermittently following dosing. Finally, a nondrug, large-scale field study involved DBS collections from an athlete and staff population over 3 years. All DBS samples were self-collected using the Tasso M20 device and were analyzed for the presence of GH using the WADA-approved GH isoforms test. Following the single dose, positive detection within 12 h of dosing was 86% and 56% sensitive on Kits 1 and 2, respectively. In the multidose study, detection within 12 h was 85% and 69% sensitive on Kits 1 and 2, respectively. No positives were detected outside the 12-h window following a single dose, wherein detection was 5.6% sensitive at 24-h in the multidose study. Combining the 12-h windows from both studies, 100% of samples had measurable recombinant (REC) and pituitary (PIT) GH concentrations above the assay LoD, 0.041 ng/ml. Finally, 1213 samples were collected in the large-scale field study: 189 showed REC and PIT concentrations above the LoD; none returned positive results. GH is detectable in capillary DBS using the isoforms method for 12-24 h following use. While detection is short lived, transitioning to a DBS self-collection method can allow more frequent testing and increase deterrence to GH abuse.

Tracking immature reticulocyte proteins for improved detection of recombinant human erythropoietin (rhEPO) abuse.

Athletes abuse recombinant human erythropoietin (rhEPO) and erythropoiesis stimulating agents to increase hemoglobin mass and improve performance. To evade detection, athletes have developed sophisticated blood doping regimens, which often include rhEPO micro-dosing. Detection of these methods requires biomarkers with increased sensitivity and a sample matrix that is more amenable to frequent testing in the field. We have developed a method to measure two immature reticulocyte proteins, CD71 and ferrochelatase (FECH), and one total erythrocyte protein, Band 3, in dried blood spots (DBS). This method was tested in response to rhEPO administration after low doses, 40 IU/kg, micro-doses, 900 IU, or saline injection in 20 healthy subjects. During administration of low-dose rhEPO, the mean CD71/Band 3 and FECH/Band 3 ratio increased by 412 ± 197% and 250 ± 44%, respectively. The mean response for the current biomarker, RET%, increased by 195 ± 35%. During administration of rhEPO micro-doses, CD71/Band 3 increased to 127 ± 25% on day 35 and 139 ± 36% on day 39, while no increase was observed in RET%. After rhEPO administration, during the washout phase, mean values decreased to a minimum of 64 ± 4% and 64 ± 11% for CD71/Band 3 and RET%, respectively. However, CD71/Band 3 remained below 75% of baseline for at least 4 weeks after rhEPO injection, while RET% returned to baseline levels. The results demonstrate that immature reticulocyte proteins have a larger response to rhEPO administration than the current biomarker, RET%, and can be monitored in the DBS matrix.

Measurement of Immature Reticulocytes in Dried Blood Spots by Mass Spectrometry.

BACKGROUND: Immature reticulocytes (IRC) are the first cells to respond to changes in erythropoiesis. For antidoping applications, measurement of IRC may improve detection of blood doping practices. Unfortunately, this small cell population has limited stability in liquid blood samples and is difficult to measure with optimal precision. We developed a method to measure 3 IRC membrane proteins in dried blood spots (DBS) to monitor changes in erythropoiesis. METHODS: DBS spots were washed with buffers to remove soluble proteins, membrane proteins remaining in the spot were digested with trypsin, and one peptide for each protein was measured by LC-MS/MS. IRC protein concentration was determined using a DBS single point calibrator. RESULTS: Intraassay precision for IRC proteins was between 5%-15%. IRC proteins were stable in DBS for 29 days at room temperature. In a longitudinal study of 25 volunteers, the mean intraindividual variation for 3 IRC proteins was 17%, 20%, and 24% from capillary blood DBS. In comparison, the mean longitudinal variation for IRC counts measured on an automated hematology analyzer was 38%. IRC protein concentration from capillary blood DBS correlated well with venous blood DBS protein concentrations. CONCLUSIONS: Measurement of IRC proteins in DBS samples provides a method to measure changes in erythropoiesis with improved analytical sensitivity, stability, and precision. When combined with the inherent advantages of capillary blood collection in the field, this method may substantially improve the detection of blood doping practices.

Evaluation of blood parameters by linear discriminant models for the detection of 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 to identify samples suspicious for the use of synthetic forms of Endogenous Anabolic Androgenic Steroids (EAAS). Multiple recent studies have suggested that monitoring of blood parameters may provide enhanced detectability of exogenous testosterone administration. Transdermal and intramuscular testosterone administration studies were carried out in 15 subjects, and the effect on blood steroidal levels, hematological parameters, and gonadotropins was evaluated. Serum testosterone and dihydrotestosterone levels increased while gonadotropin levels were suppressed after administration. A modest increase in reticulocytes was also observed. The blood parameters that were responsive to the administrations were combined into several linear discriminant models targeting both administration (on) and washout (off) phases. The models were effective in detecting the large dose intramuscular administration but were less successful in the detection of the lower dose transdermal application. The blood profiling models may provide complementary value but do not appear to be substantially more advantageous than longitudinal urinary profiling.

Evaluation of epiandrosterone as a long-term marker of testosterone use.

Identification and evaluation of long-term markers is crucial in prolonging the detection window for anabolic steroid abuse in sport. Recently, sulfoconjugated epiandrosterone was identified as a potential long-term marker for the abuse of certain endogenous anabolic agents, including testosterone, which continues to be widely used as a performance enhancing agent in sport. To evaluate the applicability of epiandrosterone sulfate as a marker for testosterone use, administration studies were conducted with multiple modes of testosterone administration - transdermal, intramuscular, and subcutaneous. A modified sample preparation method was used to collect both glucuronidated and sulfoconjugated analytes of interest. Carbon isotope ratio measurements from the administration studies are presented here. Epiandrosterone was less effective than the conventionally used target compounds for detection of the low dose application (transdermal gel). With intramuscular administration, epiandrosterone was more diagnostic than with transdermal administration, but it did not prolong the detection window more than the conventional target compounds. With subcutaneous administration, the doses administered to the subjects were varied and the effect on the epiandrosterone values was dependent on the magnitude of the dose administered. Epiandrosterone does not appear to be a useful marker in the detection of low dose testosterone administration. It is responsive to higher dose administration, but it does not provide an extension of the detection window relative to conventional target compounds.

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 establish clearly 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 15 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 excretors for whom the 5α-androstane-3α, 17ß-diol/epitestosterone (5αAdiol/E) ratio may provide more sensitivity.

Investigating oral fluid and exhaled breath as alternative matrices for anti-doping testing: Analysis of 521 matched samples.

Current anti-doping testing is primarily conducted in urine and blood. Recently, due to confounding factors with urine and blood collections such as invasiveness, cost, and stringent shipping conditions, there has been a push for the use of alternative sample matrices to ameliorate these issues. Gaining support within the anti-doping field is the use of oral fluid, and more recently exhaled breath, as viable alternative or complementary matrices to traditional urine and blood for drug testing. Thus, we designed a first-in-field study with the purpose of investigating the utility of oral fluid and exhaled breath testing, and the preference of athlete participants, comparative to conventional anti-doping methods of urine testing. To accomplish this, 521 total matched samples, consisting of exhaled breath, oral fluid, and urine samples, were collected and analyzed, and the results compared across matrices. Participants in this study preferred the exhaled breath collection (rated 4.90 ±â€¯0.34 out of 5, mean ±â€¯SD) over the oral fluid collection procedure (4.29 ±â€¯0.85), and most preferred both over urine collections. Exhaled breath resulted in the shortest collection time (2.58 ±â€¯1.00 min, mean ±â€¯SD), followed by urine (3.08 ±â€¯1.50 min), and finally oral fluid (4.14 ±â€¯1.94 min). Prohibited substances from the drug categories of stimulants, narcotics, cannabinoids, diuretics, glucocorticoids, beta-blockers, and others, were analyzed in this study for a comparison of testing efficacy. Of the total findings 49% were detectable in only urine, 38% in urine + oral fluid, and 9% in all three matrices. Of the unique findings 3% were detectable in only oral fluid, 1% in oral fluid + breath, and 0% of unique findings were present only in exhaled breath. The findings from this study provide a strong foundation for the future use of oral fluid and exhaled breath as viable alternative or complementary matrices for in-competition anti-doping testing.