The Probenecid-story - A success in the fight against doping through out-of-competition testing.

The effectiveness of doping control in sport has been improved continuously during the past 50 years. One of the major steps forward was the introduction of unannounced and targeted out-of-competition testing in order to control the misuse of anabolic-androgenic steroids (AAS), mainly during the end of the 1980s. It also led to the misuse of masking agents in case a surprise control was performed. Athletes tried to be "prepared", when the doping control officer showed up. The disclosure of the masking agent probenecid in 1987 is a perfect example of a memorable finding, of a suspected and purported case of performance manipulation. Probenecid and its metabolites were identified in five urine samples collected from Norwegian athletes in an out-of-competition test, while they were staying and training in the USA. Probenecid is a drug that reduces the urinary excretion of AAS from the body. It was the first time that it had showed up in a doping control sample. The athletes were sanctioned for hampering the analysis of their urine sample, although probenecid was not yet specified on the Prohibited List. Its detection was the result of a successful collaboration of laboratories and investigative diligence and enthusiasm following up suspicious observations in the actual samples. Immediately afterwards probenecid was added to the Prohibited List for 1988 as well as including the manipulation of doping control samples.

Terbutaline Accumulates in Blood and Urine after Daily Therapeutic Inhalation.

PURPOSE: This study investigated pharmacokinetics of terbutaline after single and seven consecutive days of inhalation in exercising trained men. METHODS: Twelve healthy trained men underwent two pharmacokinetic trials comparing single dose (2 mg) and seven consecutive days (2 mg·d) of inhaled terbutaline. After inhalation of terbutaline at each trial, subjects performed 90 min of bike ergometer exercise at 55%-65% of maximal oxygen consumption after which they stayed inactive. Blood and urine samples were collected before and after inhalation of terbutaline. Samples were analyzed by high-performance liquid chromatography-tandem mass spectrometry. RESULTS: Maximum serum concentration of terbutaline (Cmax) (6.4 ± 1.2 vs 4.9 ± 1.2 ng·mL, P = 0.01) (mean ± 95% confidence interval) and area under serum concentration-time curve from 0 to 4 h after inhalation (AUC0-4) (16 ± 3 vs 13 ± 2 ng·mL·h, P ≤ 0.005) were higher after 7 d of inhalation compared with the first day. Seven days of terbutaline inhalation resulted in accumulation of terbutaline in urine, in which total urine excretion of terbutaline was higher after 7 d of inhalation compared with the first day (274 ± 43 vs 194 ± 33 µg, P ≤ 0.001). These differences were partly attributed to systemic accumulation of terbutaline after consecutive days of inhalation, in that baseline serum and urine samples revealed incomplete elimination of terbutaline. CONCLUSION: Terbutaline accumulates in serum and urine after consecutive days of inhalation. For doping control purposes, these observations are of relevance if a urine threshold and decision limit is to be introduced for terbutaline on the World Anti-Doping Agency's list of prohibited substances because asthmatic athletes may use their bronchorelievers for consecutive days.

Pharmacokinetics of Oral and Inhaled Terbutaline after Exercise in Trained Men.

AIM: The aim of the study was to investigate pharmacokinetics of terbutaline after oral and inhaled administration in healthy trained male subjects in relation to doping control. METHODS: Twelve healthy well-trained young men (27 ±2 years; mean ± SE) underwent two pharmacokinetic trials that compared 10 mg oral terbutaline with 4 mg inhaled dry powder terbutaline. During each trial, subjects performed 90 min of bike ergometer exercise at 65% of maximal oxygen consumption. Blood (0-4 h) and urine (0-24 h) samples were collected before and after administration of terbutaline. Samples were analyzed for concentrations of terbutaline by high performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS). RESULTS: Pharmacokinetics differed between the two routes of administration. Serum Cmax and area under the serum concentration-time curve (AUC) were lower after oral administration compared to inhalation (Cmax: 4.2 ± 0.3 vs. 8.5 ± 0.7 ng/ml, P ≤ 0.001; AUC: 422 ± 22 vs. 1308 ± 119 ng/ml × min). Urine concentrations (sum of the free drug and the glucuronide) were lower after oral administration compared to inhalation 2 h (1100 ± 204 vs. 61 ± 10 ng/ml, P ≤ 0.05) and 4 h (734 ± 110 vs. 340 ± 48 ng/ml, P ≤ 0.001) following administration, whereas concentrations were higher for oral administration than inhalation 12 h following administration (190 ± 41 vs. 399 ± 108 ng/ml, P ≤ 0.05). Urine excretion rate was lower after oral administration than inhalation the first 2 h following administration (P ≤ 0.001). Systemic bioavailability ratio between the two routes of administration was 3.8:1 (inhaled: oral; P ≤ 0.001). CONCLUSION: Given the higher systemic bioavailability of inhaled terbutaline compared to oral, our results indicate that it is difficult to differentiate allowed inhaled use of terbutaline from prohibited oral ingestion based on urine concentrations in doping control analysis. However given the potential performance enhancing effect of high dose terbutaline, it is essential to establish a limit on the WADA doping list.

Pharmacokinetics of nebulized and oral procaterol in asthmatic and non-asthmatic subjects in relation to doping analysis.

The purpose of the present study was to investigate pharmacokinetics of procaterol in asthmatics and non-asthmatics after nebulized and oral administration in relation to doping. Ten asthmatic and ten non-asthmatic subjects underwent two pharmacokinetic trials. At first trial, 4 µg procaterol was administered as nebulization. At second trial, 100 µg procaterol was administered orally. Serum and urine samples were collected before and after administration of procaterol. Samples were analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Serum and urine concentrations of procaterol were markedly higher after oral administration compared to nebulized administration. After oral administration, serum procaterol concentration-time area under the curve (AUC) was higher (P ≤ 0.05) for asthmatics than non-asthmatics. Likewise, urine concentrations were higher (P ≤ 0.01) for asthmatics than non-asthmatics 4 (47 ± 12 vs. 28 ± 9 ng/mL) and 8 h (39 ± 9 vs. 15 ± 5 ng/mL) after oral administration. Detection of serum procaterol was difficult after nebulized administration with 38 samples (27%) below limit of quantification (LOQ) and only trends were observed. No differences were observed between asthmatics and non-asthmatics in the urine concentrations of procaterol after nebulized administration. In summary, our data showed that asthmatics had higher urine concentrations of procaterol than non-asthmatics after oral administration of 100 µg, whereas no difference was observed between the groups after nebulized administration. For doping control purposes, our observations indicate that it is possible to differentiate therapeutic nebulized administration of procaterol from prohibited use of oral procaterol. Copyright © 2016 John Wiley & Sons, Ltd.

The influence of exercise and dehydration on the urine concentrations of salbutamol after inhaled administration of 1600 µg salbutamol as a single dose in relation to doping analysis.

The present study investigated the influence of exercise and dehydration on the urine concentrations of salbutamol after inhalation of that maximal permitted (1600 µg) on the 2015 World Anti-Doping Agency (WADA) prohibited list. Thirteen healthy males participated in the study. Urine concentrations of salbutamol were measured during three conditions: exercise (EX), exercise+dehydration (EXD), and rest (R). Exercise consisted of 75 min cycling at 60% of VO2max and a 20-km time-trial. Fluid intake was 2300, 270, and 1100 mL during EX, EXD, and R, respectively. Urine samples of salbutamol were collected 0-24 h after drug administration. Adjustment of urine concentrations of salbutamol to a specific gravity (USG) of 1.020 g/mL was compared with no adjustment. The 2015 WADA decision limit (1200 ng/mL) for salbutamol was exceeded in 23, 31, and 10% of the urine samples during EX, EXD, and R, respectively, when unadjusted for USG. When adjusted for USG, the corresponding percentages fell to 21, 15, and 8%. During EXD, mean urine concentrations of salbutamol exceeded (1325±599 ng/mL) the decision limit 4 h after administration when unadjusted for USG. Serum salbutamol Cmax was lower (P<0.01) for R(3.0±0.7 ng/mL) than EX(3.8±0.8 ng/mL) and EXD(3.6±0.8 ng/mL). AUC was lower for R (14.1±2.8 ng/mL·âˆ™h) than EX (16.9±2.9 ng/mL·âˆ™h)(P<0.01) and EXD (16.1±3.2 ng/mL·âˆ™h)(P<0.05). In conclusion, exercise and dehydration affect urine concentrations of salbutamol and increase the risk of Adverse Analytical Findings in samples collected after inhalation of that maximal permitted (1600 µg) for salbutamol. This should be taken into account when evaluating doping cases of salbutamol. Copyright © 2015 John Wiley & Sons, Ltd.

Black market products confiscated in Norway 2011-2014 compared to analytical findings in urine samples.

Doping agents are widely and illicitly distributed through the Internet. Analysis of these preparations is useful in order to monitor the availability of prohibited substances on the market, and more importantly to predict which substances are expected to be found in urine samples collected from athletes and to aid clinical and forensic investigations. Based on a close collaboration with the Norwegian police and the Norwegian custom authorities, the Norwegian Doping Control Laboratory has performed analyses of confiscated material suspected of containing doping agents. The analyses were performed using gas chromatography (GC) and liquid chromatography (LC) combined with mass spectrometry (MS). The majority (67%) of the analyzed black market products contained anabolic- androgenic steroids (AAS) as expected, whereas peptide- and protein-based doping substances were identified in 28% of the preparations. The Norwegian Doping Control Laboratory receives samples collected from recreational and elite athletes in addition to samples collected in clinical and forensic investigations. The findings in the seized material reflected the findings in the urine samples analyzed regarding the anabolic steroids. Thus, analyzing material seized in Norway may give a good indication of doping agents available on the local market.

Carbon isotope ratios of nandrolone, boldenone, and testosterone preparations seized in Norway compared to those of endogenously produced steroids in a Nordic reference population.

Determining the origin of anabolic androgenic steroids (AAS) that also are produced endogenously in the human body is a major issue in doping control. In some cases, the presence of nandrolone and boldenone metabolites might result from endogenous production. The GC-C-IRMS technique (gas chromatography-combustion-isotope ratio mass spectrometry) enables the carbon isotopic ratio (CIR) to be measured to determine the origin of these metabolites. The aim of this study was to use GC-C-IRMS to determine the δ(13) CVPDB values of seized boldenone and nandrolone preparations to decide if the steroids themselves were depleted in (13) C, compared to what is normally seen in endogenously produced steroids. In addition, several testosterone preparations were analyzed. A total of 69 seized preparations were analyzed. The nandrolone preparations showed δ(13) CVPDB values in the range of -31.5 ‰ to -26.7 ‰. The boldenone preparations showed δ(13) CVPDB values in the range of -32.0 ‰ to -27.8 ‰, and for comparison the testosterone preparations showed δ(13) CVPDB values of -31.0 ‰ to -24.2 ‰. The results showed that the values measured in the nandrolone and boldenone preparations were in the same range as those measured in the testosterone preparations. The study also included measurements of CIR of endogenously produced steroids in a Norwegian/Danish reference population. The δ(13) CVPDB values measured for the endogenous steroids in this population were in the range of -21.7 to -26.8. In general, most of the preparations investigated in this study show (13) C-depleted delta values compared to endogenously produced steroids reflecting a northern European diet.

MAIIA EPO SeLect-a rapid screening kit for the detection of recombinant EPO analogues in doping control: inter-laboratory prevalidation and normative study of athlete urine and plasma samples.

Recombinant analogues of erythropoietin (EPO), epoetins, have been misused by athletes due to their performance enhancing effect since the first pharmaceutical epoetin was launched in 1987. The current methods for screening urine and plasma samples for the presence of epoetins, IEF and SAR-PAGE, have high sensitivity but are time-consuming to carry out. In an effort to ease and speed up the screening procedure for EPO, MAIIA Diagnostics has developed a combined affinity chromatography and lateral flow immunoassay, MAIIA EPO SeLect, which determines the percentage of migrated isoforms (PMI) of EPO in a sample. The reproducibility of the kit was tested by analyzing a set of negative and positive urine and plasma samples in three different laboratories. All data were analyzed with both curve fit parameters from the individual assay runs, and with lot-specific predefined curve calibration. To get a measure of endogenous variation, a normative study with athlete urine and plasma samples was conducted. The average intra-laboratory variation was 6.7% while the inter-laboratory variation for all samples was calculated to 8.8%. The athlete samples yielded an average PMI and standard deviation of 71.4 ± 7.7 for urine and 83.1 ± 10.2 for plasma, respectively. There were no signs of deviating results from tested effort urines. The results also support the use of predefined curve parameters.

Effect of inhaled terbutaline on substrate utilization and 300-kcal time trial performance.

In a randomized, double-blind crossover design, we investigated the effect of the beta2-agonist terbutaline (TER) on endurance performance and substrate utilization in nine moderately trained men [maximum oxygen uptake (V̇O(2 max)) 58.9 ± 3.1 ml·min(-1)·kg(-1)]. Subjects performed 60 min of submaximal exercise (65-70% of V̇O(2 max)) immediately followed by a 300-kcal time trial with inhalation of either 15 mg of TER or placebo (PLA). Pulmonary gas exchange was measured during the submaximal exercise, and muscle biopsies were collected before and after the exercise bouts. Time trial performance was not different between TER and PLA (1,072 ± 145 vs. 1,054 ± 125 s). During the submaximal exercise, respiratory exchange ratio, glycogen breakdown (TER 266 ± 32, PLA 195 ± 28 mmol/kg dw), and muscle lactate accumulation (TER 20.3 ± 1.6, PLA 13.2 ± 1.2 mmol/kg dw) were higher (P < 0.05) with TER than PLA. There was no difference between TER and PLA in net muscle glycogen utilization or lactate accumulation during the time trial. Intramyocellular triacylglycerol content did not change with treatment or exercise. Pyruvate dehydrogenase-E1α phosphorylation at Ser(293) and Ser(300) was lower (P < 0.05) before submaximal exercise with TER than PLA, with no difference after the submaximal exercise and the time trial. Before submaximal exercise, acetyl-CoA carboxylase 2 (ACC2) phosphorylation at Ser(221) was higher (P < 0.05) with TER than PLA. There was no difference in phosphorylation of alpha 5'-AMP-activated protein kinase (αAMPK) at Thr(172) between treatments. The present study suggests that beta2-agonists do not enhance 300-kcal time trial performance, but they increase carbohydrate metabolism in skeletal muscles during submaximal exercise independent of AMPK and ACC phosphorylation, and that this effect diminishes as drug exposure time, exercise duration, and intensity are increased.

High-dose inhaled terbutaline increases muscle strength and enhances maximal sprint performance in trained men.

PURPOSE: The purpose of the present study was to investigate the effect of high-dose inhaled terbutaline on muscle strength, maximal sprinting, and time-trial performance in trained men. METHODS: Nine non-asthmatic males with a VSO2max of 58.9 ± 3.1 ml min(-1) kg(-1) (mean ± SEM) participated in a double-blinded randomized crossover study. After administration of inhaled terbutaline (30 × 0.5 mg) or placebo, subjects' maximal voluntary isometric contraction (MVC) of m.quadriceps was measured. After MVC, subjects performed a 30-s Wingate test. Sixty minutes following the Wingate test, subjects exercised for 10 min at 80% of VSO2max and completed a 100-kcal time trial. Aerobic contribution was determined during the Wingate test by indirect calorimetry. Furthermore, plasma terbutaline, lactate, glucose, and K(+) were measured. RESULTS: Inhalation of 15 mg terbutaline resulted in systemic concentrations of terbutaline of 23.6 ± 1.1 ng ml(-1) 30 min after administration, and elevated plasma lactate (P = 0.001) and glucose (P = 0.007). MVC was higher for terbutaline than placebo (738 ± 64 vs. 681 ± 68 N) (P = 0.007). In addition, Wingate peak power and mean power were 2.2 ± 0.8 (P = 0.019) and 3.3 ± 1.0% (P = 0.009) higher for terbutaline than placebo. Net accumulation of plasma lactate was higher (P = 0.003) for terbutaline than placebo during the Wingate test, whereas [Formula: see text] above baseline was unchanged by terbutaline (P = 0.882). Time-trial performance was not different between treatments (P = 0.236). CONCLUSION: High-dose inhaled terbutaline elicits a systemic response that enhances muscle strength and sprint performance. High-dose terbutaline should therefore continue to be restricted in competitive sport.

Urine concentrations of oral salbutamol in samples collected after intense exercise in endurance athletes.

Our objective was to investigate urine concentrations of 8 mg oral salbutamol in samples collected after intense exercise in endurance athletes. Nine male endurance athletes with a VO2max of 70.2 ± 5.9 mL/min/kg (mean ± SD) took part in the study. Two hours after administration of 8 mg oral salbutamol, subjects performed submaximal exercise for 15 min followed by two, 2-min exercise bouts at an intensity corresponding to 110% of VO2max and a bout to exhaustion at same intensity. Urine samples were collected 4, 8, and 12 h following administration of salbutamol. Samples were analyzed by the Norwegian World Anti-doping Agency (WADA) laboratory. Adjustment of urine concentrations of salbutamol to a urine specific gravity (USG) of 1.020 g/mL was compared with no adjustment according to WADA's technical documents. We observed greater (P = 0.01) urine concentrations of salbutamol 4 h after administration when samples were adjusted to a USG of 1.020 g/mL compared with no adjustment (3089 ± 911 vs. 1918 ± 1081 ng/mL). With the current urine decision limit of 1200 ng/mL for salbutamol on WADA's 2013 list of prohibited substances, fewer false negative urine samples were observed when adjusted to a USG of 1.020 g/mL compared with no adjustment. In conclusion, adjustment of urine samples to a USG of 1.020 g/mL decreases risk of false negative doping tests after administration of oral salbutamol. Adjusting urine samples for USG might be useful when evaluating urine concentrations of salbutamol in doping cases.

Comparison of newly developed immuno-MS method with existing DELFIA(®) immunoassay for human chorionic gonadotropin determination in doping analysis.

BACKGROUND: The performance of a method for MS determination of human chorionic gonadotropin (hCG) was compared with a reference method currently used in World Anti-Doping Agency accredited doping laboratories - the DELFIA(®) immunoassay. RESULTS: A strong correlation was demonstrated for the serum samples. However, for the urine samples, DELFIA reported significantly lower quantitative hCG measurements than the MS method. This was explained by the relatively unstable content of intact hCG-heterodimer in urine during storage compared with in serum. Discrepancies observed for the urine analyses might be related to the molecular dissociation of intact hCG-heterodimer into free subunits during storage, and the direct effect this has on the intact hCG measurements provided by DELFIA. The MS method quantified both intact hCG and free hCG ß-subunit simultaneously, and was thus less susceptible to this problem. However, both methods detected illicit levels of serum hCG an equally long time after administration. CONCLUSION: The presented work advocates the implementation of this MS method as a confirmatory method for hCG determination in doping laboratories.

Formoterol concentrations in blood and urine: the World Anti-Doping Agency 2012 regulations.

INTRODUCTION: We examined urinary and serum concentrations of formoterol in asthmatic and healthy individuals after a single dose of 18 µg inhaled formoterol and after repeated inhaled doses in healthy individuals. Results were evaluated using the World Anti-Doping Agency (WADA) 2012 threshold for formoterol. METHODS: On the day of this open-label, crossover study, 10 asthmatic subjects who regularly used beta2-agonists and 10 healthy participants with no previous use of beta2-agonists received a single dose of 18 µg formoterol. Further, 10 nonasthmatic participants inhaled 18 µg formoterol every second hour until obtaining a total of 72 µg, which is twice the maximum daily dose (36 µg formoterol) permitted by the WADA. Blood samples were collected at baseline, 30 min, 1, 2, 3, 4, and 6 h after the first inhalation. Urine samples were collected at baseline, 0-4, 4-8, and 8-12 h after the first inhalation. RESULTS: Median urine concentration, corrected for specific gravity, after the single-dose administration peaked during 0-4 h after inhalation at a maximum of 7.4 ng·mL(-1) in asthmatic subjects and 7.9 ng·mL(-1) in healthy subjects. Median urine concentration after repeated doses peaked during 4-8 h after inhalation of a total of 72 µg formoterol at a maximum of 16.8 ng·mL(-1) in healthy participants. The maximum individual concentration of 25.6 ng·mL(-1) was found after inhalation of a total of 72 µg formoterol. CONCLUSIONS: We found no significant differences in urinary and serum concentrations of formoterol between asthmatic and healthy subjects. We found high interindividual variability in the concentrations in all groups. Our data support the WADA 2012 urinary threshold of 30 ng·mL(-1) formoterol as being an adverse analytical finding.

Sports drug testing using immuno-MS: clinical study comprising administration of human chorionic gonadotropin to males.

The applicability of a mass spectrometry (MS)-based method for determination of various forms of human chorionic gonadotropin (hCG) in doping analysis was demonstrated. A clinical study involving the hCG-containing pharmaceuticals Pregnyl and Ovitrelle was carried out, comprising a single injection of one pharmaceutical per participant to a total of 24 healthy male voluntaries. Hereafter, serum and urine samples were collected over a period of 14 days. The analysis of the samples using immuno-MS demonstrated elimination profiles of intact hCG for both pharmaceuticals, with last day of detection following administration at day 7 in serum, and at day 10 in urine, at limit of detections as defined by the World Anti-Doping Agency. Furthermore, the method allowed detection and differentiation of the various forms of hCG known to be present in serum and urine as a function of metabolism. For both pharmaceuticals, only the intact hCG was detected in serum, whereas in urine the injection of Pregnyl as hCG source (containing urinary hCG, i.e., most hCG variants) was shown to generate a more complex hCG variant pattern compared to Ovitrelle (contains only intact hCG). By detecting hCG using this MS-based approach in doping analysis, strong analytical evidence is provided minimizing the risk of false-positive and false-negative results.

The pharmacokinetic profile of inhaled and oral salbutamol in elite athletes with asthma and nonasthmatic subjects.

OBJECTIVE: Data on pharmacokinetics of inhaled and oral salbutamol in elite athletes with asthma are needed to differentiate between therapeutic use and doping in doping control. DESIGN: An interventional open-label crossover. SETTING: Respiratory Research Unit, Copenhagen University Hospital, Bispebjerg. PARTICIPANTS: Eight elite athletes with asthma and 10 nonasthmatic subjects aged 18 to 33 years. INTERVENTION: Administration of 0.8 mg of inhaled salbutamol and 8 mg of oral salbutamol separated by 14 days. MAIN OUTCOME MEASURES: Urine concentration of free salbutamol. RESULTS: Maximum urine concentrations peaked in the period of 0 to 4 hours after the administration of inhaled and oral salbutamol in both groups. Median concentrations after inhaled salbutamol and oral salbutamol were 401.6 and 2108.1 ng/mL in healthy subjects and 334.9 and 2975.2 ng/mL in elite athletes with asthma. There were no significant statistical differences between the groups. One sample exceeded the World Anti-Doping Agency threshold value of 1000 ng/mL with a urinary salbutamol concentration of 1057 ng/mL 4 hours after inhalation, when no correction for urine specific gravity was done. When this sample was corrected for urine specific gravity, the result was 661 ng/mL. CONCLUSIONS: We found no significant difference in pharmacokinetic profile of inhaled and oral salbutamol between elite athletes with asthma and nonasthmatic subjects. Our results indicate that urine salbutamol concentrations should be corrected for urine specific gravity when evaluating doping cases.

Effect of single doses of methoxypolyethylene glycol-epoetin beta (CERA, Mircera™) and epoetin delta (Dynepo™) on isoelectric erythropoietin profiles and haematological parameters.

Erythropoietin (EPO) has been misused in sports for many years due to its performance-enhancing effect. In the last decade, detection of abuse has been possible with isoelectric focusing (IEF) based on the different isoform profiles of endogenous and recombinant EPO. The release of new EPOs on the market, such as the recombinant erythropoietin epoetin delta (Dynepo™) and the chemically modified EPO, CERA (Mircera™) potentially represents analytical challenges to the fight against doping. This study set out to investigate the possibility of and the time window for detecting the administration of a single dose of Dynepo™ and CERA. Our results are in agreement with earlier findings that detection of Dynepo™ is best achieved by combining IEF with SDS-PAGE. Haematological parameters were monitored for possible effects due to the long half-life (130 hours) of CERA in blood. Interestingly, although several haematological parameters were significantly changed after the injection of CERA, the endogenous EPO signal was still present in all collected samples. Due to the long half-life and the large size of the CERA molecule (about 60 kDa), it was uncertain whether CERA would be excreted into urine in detectable amounts unless urine collection was preceded by strenuous physical exercise. We find that CERA can be detected in urine without prior exercise in several, but not all, subjects. CERA is nevertheless best detected in serum with regard to both probability and length of detection, in addition to stability in matrix over time.