Identification of budesonide metabolites in human urine after oral administration

Abstract

Budesonide (BUD) is a glucocorticoid widely used for the treatment of asthma, rhinitis, and inflammatory bowel disease. Its use in sport competitions is prohibited when administered by oral, intravenous, intramuscular, or rectal routes. However, topical preparations are not prohibited. Strategies to discriminate between legal and forbidden administrations have to be developed by doping control laboratories. For this reason, metabolism of BUD has been re-evaluated using liquid chromatography-tandem mass spectrometry (LC-MS/MS) with different scan methods. Urine samples obtained after oral administration of 3 mg of BUD to two healthy volunteers have been analyzed for metabolite detection in free and glucuronide metabolic fractions. Structures of the metabolites have been studied by LC-MS/MS using collision induced dissociation and gas chromatography-mass spectrometry (GC/MS) in full scan mode with electron ionization. Combination of all structural information allowed the proposition of the most comprehensive picture for BUD metabolism in humans to this date. Overall, 16 metabolites including ten previously unreported compounds have been detected. The main metabolite is 16α-hydroxy-prednisolone resulting from the cleavage of the acetal group. Other metabolites without the acetal group have been identified such as those resulting from reduction of C20 carbonyl group, oxidation of the C11 hydroxyl group and reduction of the A ring. Metabolites maintaining the acetal group have also been identified, resulting from 6-hydroxylation (6α and 6β-hydroxy-budesonide), 23-hydroxylation, reduction of C6-C7, oxidation of the C11 hydroxyl group, and reduction of the C20 carbonyl group. Metabolites were mainly excreted in the free fraction. All of them were excreted in urine during the first 24 h after administration, and seven of them were still detected up to 48 h after administration for both volunteers.

Detection and characterization of prednisolone metabolites in human urine by LC-MS/MS

“…S1). The base peak at m / z 171 and low abundance of peaks at m / z 121 and 147 of Δ 6 ‐PRED were in agreement with mass spectra of previously described 6,7‐dehydrometabolites of budesonide and of methylprednisolone …”

“…(E)). NL of 30 Da was present in 20 β ‐dihydro‐prednisone and has been reported in other corticosteroids, but its origin is not clear. The NL of 26 Da corresponds to a loss of acetylene .…”

“…Liquid chromatography coupled to tandem mass spectrometry (LC‐MS/MS) has demonstrated to be a useful tool for the identification of new metabolites of compounds with steroid structure, including glucocorticosteroids . The use of this technology is especially important for glucocorticosteroids because of the difficulties to obtain adequate derivatives of polyoxygenated metabolites to make them amenable to gas chromatography–mass spectrometry analysis …”

Elimination profile of triamcinolone hexacetonide and its metabolites in human urine and plasma after a single intra‐articular administration

“…As a consequence, great research activity has been developed to find strategies to distinguish allowed from forbidden administration for some compounds of the group. [11][12][13][14][15][16][17][18][19][20][21] For triamcinolone acetonide (TA), a drug related to THA, a previous study showed that a reporting level of 30 ng/mL was not able to detect forbidden IM administration. The use of a reporting level of 5 ng/mL was suggested to detect IM use as well as to distinguish IM from topical and intranasal administrations.…”

Urinary excretion profile of prednisone and prednisolone after different administration routes

“…Previous studies carried out after the administration of different glucocorticoids (not only prednisone/prednisolone, but also methylprednisolone, budesonide, betamethasone and triamcinolone acetonide) have already shown that the reporting level of 30 ng/mL might not always be adequate for all glucocorticoids, especially in the case the parent compound is the only targeted analyte detected. [15][16][17][18][19][20][21][22] The goal of this study was focused on the definition of the excretion profile of both prednisone and prednisolone after the intake, via different routes, of therapeutic doses of some pharmaceutical formulations containing either prednisone or prednisolone, in order to select the most appropriate marker(s) of abuse, i.e., target(s) compound(s) excreted in urine in a concentration greater than 30 ng/mL for at least 24 h from the intake of the drug only in the case of systemic administration, and not produced in situ from natural steroids (i.e., cortisol and cortisone) by specific microorganisms.…”