Evidence of ostarine excretion in oral fluid after a single controlled oral administration

Abstract

The presence of ostarine, a selective androgen receptor modulator (SARM) in an athlete’s urine specimen constitutes one of the most frequent anti-doping rules violation as the drug is listed as a member of the S1.2 class “other anabolic agents” of the World Anti-doping Agency Prohibited List, forbidden in- and out-competition. It is possible to challenge this violation but it is at the charge of the athlete to prove innocence. The conditions to evidence no fault or negligence are mostly based on 2 points: 1. the athlete must present verified circumstances of contamination and the source of contamination must be identified; and 2. there must be verified claims by the athlete that the violation was not intentional.Some months before the Olympic games, a female athlete was suspended by a national anti-doping agency because of an adverse analytical finding for ostarine. She claimed that her violation was due to drug transfer when kissing her boyfriend, who did not inform her about his ostarine daily intake. To document this claim (excretion of ostarine in oral fluid in sufficient amounts), a male volunteer ingested 17.3 mg of ostarine (dose verified by 1H NMR). Oral fluid was collected over 8 h using the NeoSal™ collection device and was tested by liquid chromatography coupled to tandem mass spectrometry. Maximal ostarine concentration was 468 ng/mL at T + 15 min, which can also be partially attributed to mouth contamination. Ostarine was detectable during the whole period of test, with concentrations at 1–2 ng/mL after T + 4 h. These results support drug transfer during kissing and subsequent possible contamination of the partner.