Analytical detection of trimetazidine produced by metabolic conversion of lomerizine in doping control analysis

Self Cite

There has been an immense amount of visibility of doping issues on the international stage over the past 12 months with the complexity of doping controls reiterated on various occasions. Hence, analytical test methods continuously being updated, expanded, and improved to provide specific, sensitive, and comprehensive test results in line with the World Anti-Doping Agency's (WADA) 2016 Prohibited List represent one of several critical cornerstones of doping controls. This enterprise necessitates expediting the (combined) exploitation of newly generated information on novel and/or superior target analytes for sports drug testing assays, drug elimination profiles, alternative test matrices, and recent advances in instrumental developments. This paper is a continuation of the series of annual banned-substance reviews appraising the literature published between October 2015 and September 2016 concerning human sports drug testing in the context of WADA's 2016 Prohibited List. Copyright © 2016 John Wiley & Sons, Ltd.

Section: Hormone and Metabolic Modulatorsmentioning

confidence: 99%

Annual banned‐substance review: analytical approaches in human sports drug testing

Thevis

Kuuranne

Geyer

et al. 2017

Self Cite

“…In our earlier study, 5 we demonstrated that when trimetazidine is found in urine samples, further analyses concerning the intact drug lomerizine and/or the metabolite bis-(4fluorophenyl)-methylpiperazine (M6) are indicated. In our earlier study, 5 we demonstrated that when trimetazidine is found in urine samples, further analyses concerning the intact drug lomerizine and/or the metabolite bis-(4fluorophenyl)-methylpiperazine (M6) are indicated.…”

Section: Introductionmentioning

confidence: 99%

“…13 Trimetazidine is generally identified by means of liquid chromatography-tandem mass spectrometry (LC-MS/MS) 5,14 and gas chromatography-mass spectrometry (GC-MS). Mass spectrometric analysis has been the preferred technology for the reliable identification of substances in sports drug testing.…”

Section: Introductionmentioning

confidence: 99%

“…Fragment ions were assigned in the previous study 5. Targeted quantification was performed using the parallel reaction monitoring mode.…”

mentioning

confidence: 99%

“…can be identified as a urinary metabolite after the administration of lomerizine. [3][4][5] Therefore, the discrimination between the abuse of the prohibited substance trimetazidine and the use of the permitted drug lomerizine is essential to appropriate result management in doping controls. Miyanaga et al reported that the metabolism of lomerizine was catalyzed by four microsomal human cytochrome P450 isoforms (CYPs), specifically CYP2C8, 2C9, 2D6, and 3A4.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Lomerizine, trimetazidine and bis‐(4‐fluorophenyl)‐methylpiperazine in human urine after oral administration of lomerizine dihydrochloride: analysis by liquid chromatography‐high resolution‐tandem mass spectrometry

Okano¹,

Sato²,

Kageyama³

2018

Self Cite

In sports drugs testing, the differentiation between the abuse of the prohibited substance trimetazidine and that of the permitted drug lomerizine is required because trimetazidine is one of the metabolites of lomerizine. Therefore, it is important to identify a lomerizine-specific metabolite in urine that allows making the distinction.In this study, a simple dilute-and-shoot method employing liquid chromatographyhigh resolution-tandem mass spectrometry for the quantification of trimetazidine, lomerizine and the specific metabolite bis-(4-fluorophenyl)-methylpiperazine (M6) in urine was developed. An oral dose of 15 mg was administered to 10 male volunteers, after which urine samples collected during the following 276 hours were analyzed using the developed method, allowing for examination of the target analytes' excretion profile. The limit of detection of all target analytes was <0.02 ng/mL. In all volunteers, the metabolite M6 was detected up to 276 hours after administration. After more than 12 hours, all volunteers were found to have higher concentrations of the metabolite M6 than of trimetazidine. The concentrations of trimetazidine, lomerizine, M6, and the M6/trimetazidine ratio in the final sample collected after 276 hours were 0.2-0.9 ng/mL, <0.05-0.1 ng/mL, 14.1-38.3 ng/mL, and 28.8-122.9, respectively.The urinary excretion of trimetazidine, unchanged lomerizine, and the metabolite M6 within the first 276 hours was 0.64%, 0.006%, and 6.1%, respectively. Consequently, the absence of the metabolite M6 in doping control urine samples corroborates the conclusion that lomerizine is unlikely to be the source of trimetazidine.The results confirm that the M6 metabolite is the longest-lasting urinary metabolite of lomerizine currently known.

Doping control analysis of trimetazidine in dried blood spot

Okano¹,

Miyamoto²,

Ota³

et al. 2022

Dried blood spot (DBS) analysis has been an inherent part of sports drug testing through the technological advancements of the past decade. Trimetazidine, a non‐threshold banned substance, is excreted into urine after a dose of the permitted drug lomerizine. Therefore, a lomerizine‐specific metabolite (M6) is analyzed to confirm the origin of trimetazidine in traditional urine analysis. Application studies were conducted to develop an analytical method for trimetazidine applicable to DBS. These studies comprise (1) the effect of different sampling sites on the detection of trimetazidine, (2) the determination of the appropriate trimetazidine level required for DBS analysis, and (3) differentiating between trimetazidine and lomerizine use. A high‐resolution mass spectrometric method for detecting trimetazidine in DBS was validated. After oral administration of trimetazidine (n = 7), venous and capillary blood (fingertip and upper arm) were spotted on cellulose paper. Trimetazidine could be identified in DBS in all subjects up to 60 h after administration. The limit of detection was 0.05 ng/ml, and the limit of identification was 0.06 ng/ml, suggesting the minimum required performance level of 0.2 ng/ml. In the fingertip capillary blood, biases of 9.7% (vs. upper arm) and 13.0% (vs. vein) were observed in the trimetazidine intensity; however, there were no concerns in the qualitative analysis. After administering lomerizine (n = 10), the intact lomerizine has a strong peak intensity in blood compared to trimetazidine. Contrary to urine analysis, the M6 was less detectable in blood. Laboratories should confirm intact lomerizine whenever trimetazidine is identified in DBS.