The mystery surrounding Australian motocross racers Jake and Matt Moss has been resolved. The Moss’ both failed a WADA drug for the drug Ostarine, also known as MK-2866. Ostarine is a Selective Androgen Receptor Modulators (SARMs). This therapeutic compound has similar properties to anabolic agents, but with a lack of steroid-related side effects. SARMs have been prohibited by the World Anti-Doping Agency (WADA) since 2008. SARMs are considered performance-enhancing drugs due to their anabolic properties, as well as ability to stimulate androgen receptors in muscle and bone. The most common SARMs are Ostarine and Andarine.

Jake Moss and older brother Matt have confirmed that they have tested positive to a prohibited substance under the World Anti-Doping Code. Waiting the results of the B-sample test and any appeals, the Moss brothers have been banned from racing world-wide. Both Moss’ are appealing the WADA ban.

Jake Moss said, “As you may know, I recently announced my retirement from racing. As I said at the time, this decision to retire was based upon my decision to focus on my family and career away from competitive motocross and Supercross racing. I have recently been advised through Motorcycling Australia and ASADA that I have allegedly tested positive to Ostarine, which is a prohibited substance under the World Anti-Doping Code. I do not accept the results of the test and I am in the process of challenging those results through the appropriate processes.”

Matt Moss said, “I wanted to let everyone know that the reason I haven’t been racing lately is that an issue has arisen through a random urine test I recently undertook for ASADA. I have been provisionally suspended from participating. I am at a loss to understand how the issue has arisen and I am in the process of challenging the results of the test through the appropriate processes. I am confident of being cleared and I look forward to returning to the sport I love as soon as possible.”


“Bound by the ASADA Act and ASADA Regulations, the Code, the WADA International Standard for the Protection of Privacy and Personal Information and the Privacy Act, Motorcycling Australia can now confirm that on 22nd of May 2016 the Australian Sports Anti-Doping Authority (ASADA) tested four individual athletes at the MX Nationals round held at Murray Bridge in South Australia.


“Motorcycling Australia can also confirm that samples provided by both Jake Moss and Matt Moss have tested positive for Ostarine, a substance prohibited for use in sport under the World Anti-Doping Agency’s Prohibited List.

“Both Jake and Matt Moss are now under investigation by ASADA and have been provisionally suspended by Motorcycling Australia from any activity in their sport until the matter is resolved as per ASADA’s guidelines. The other two riders tested at the same time – Dean Ferris and Nathan Crawford – had no adverse analytical findings.


australian motocrossjake mossmatt mossmotocrosswada