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Amanda Ribas Granted a Reduced Sanction Under UFC Anti-Doping Policy

The U.S. Anti-Doping Agency (USADA) announced today that an athlete in the UFC® Anti-Doping Program, Amanda Ribas, of Minas Gerais, Brazil, is entitled to a reduction in her original two-year suspension. Ribas’ period of ineligibility has been terminated, effective immediately.

Ribas, 24, tested positive for ostarine following an out-of-competition urine test conducted on June 7, 2017. Ostarine is a non-Specified Substance in the class of Anabolic Agents and prohibited at all times under the UFC Anti-Doping Policy, which has adopted the World Anti-Doping Agency Prohibited List.

Ostarine, also known as MK-2866 and Enobosarm, is a non-FDA approved selective androgen receptor modulator (SARM) that is illegally sold in supplements in the United States and worldwide as a performance-enhancing substance. SARMs are synthetic drugs that replicate the effects of testosterone and they have been linked to serious health risks, including liver damage and increased risk of heart attack or stroke. It is illegal to include SARMs in dietary supplements, but the ingredients are sometimes found in contaminated products, particularly bodybuilding products, that are falsely labeled as dietary supplements. In recent years, the World Anti-Doping Agency has reported an increasing number of positive tests involving SARMs.

The FDA has also increased its efforts to prevent the spread of SARMs in supplements and USADA has supported legislative efforts, including the SARMs Control Act, to improve the Drug Enforcement Agency’s ability to act against SARMs. USADA has provided more information about the risks of ostarine in an athlete advisory.

The termination of Ribas’ sanction reflects USADA’s recognition of the demonstrated prevalence of ostarine in a wide range of supplement products used by athletes (see USADA High Risk List for more than 70 products) and that ostarine has frequently been found as a product contaminant. The trace amounts of ostarine found in Ribas’ sample was made possible by sensitive laboratory detection capabilities and has been followed by four negative tests. As Ribas was unable to identify the source of her positive test, and taking into consideration the likelihood that her positive test was the result of an ostarine contaminated dietary supplement product, USADA believes it is fair to allow Ribas to return to competition after serving the majority of her two-year sanction.

The Nevada State Athletic Commission also sanctioned Ribas for two years, and USADA has informed the Commission of its decision to reduce Ribas’ sanction under the UFC Anti-Doping Policy.

USADA conducts the year-round, independent anti-doping program for all UFC athletes. USADA is an independent, non-profit, non-governmental agency whose sole mission is to preserve the integrity of competition, inspire true sport, and protect the rights of clean athletes. In an effort to aid UFC athletes, as well as their support team members, in understanding the rules applicable to them, USADA provides comprehensive instruction on the UFC Anti-Doping Program website (https://UFC.USADA.org) regarding the testing process and prohibited substances, how to obtain permission to use a necessary medication, and the risks and dangers of taking supplements as well as performance-enhancing and recreational drugs. In addition, the agency manages a drug reference hotline, Drug Reference Online (https://UFC.GlobalDRO.com), conducts educational sessions, and proactively distributes a multitude of educational materials, such as the Prohibited List, easy-reference wallet cards, and periodic athlete alerts. Many of the resources available to athletes are provided in multiple languages, including Russian, Spanish, French, Portuguese, Korean, and Japanese.

Along with education and testing, robust anti-doping programs enable investigations stemming from tips and whistleblowers. USADA makes available a number of ways to report the abuse of performance-enhancing drugs in sport in an effort to protect clean athletes and promote clean competition. Any tip can be reported using the USADA Play Clean Tip Center, by email at playclean@usada.org, by phone at 1 877-Play Clean (1-877-752-9253), or by mail.


For more information or media inquiries, email media@usada.org.

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