The International Cycling Union, the sport's governing body, has confirmed a leaked memo which revealed the shamed former champion returned four positive tests for corticosteroids.
Cycling chiefs admit Lance Armstrong tested positive four times during 1999 Tour de France
Cycling's governing body has defended its actions after it emerged that shamed former champion Lance Armstrong returned positive tests four times during the 1999 Tour de France.
The former US Postal rider, who confessed to doping in January, was know to have tested positive for corticosteroids once during the race.
But now the International Cycling Union (UCI) has confirmed a leaked memo which states there were four positive tests during that year's race.
At the time, the UCI accepted that the traces came from cream used to treat saddle-soreness after Armstrong produced a therapeutic use exemption (TUE) certificate. The disgraced former Olympian admitted this year the medical certificate had been backdated.
In a nine-page document explaining the background, the UCI also confirmed that retests of Armstrong's 1999 samples in 2005 also showed the presence of the blood-boosting agent EPO. The lack of B samples to test, however, made it impossible to charge Armstrong with a doping offence.
"It should be stressed that this case was handled knowing only the facts which were apparent at that time," the document states.
"For example, the UCI did not know that the medical certificate handed over to Dr. Schattenberg, a member of UCI's Anti-doping Commission, in July 1999 had been postdated. Armstrong only admitted this during his interview with Oprah Winfrey, which was broadcast on 17 January 2013."
In relation to the EPO, the UCI said the retests could not be taken as proof of doping.
The UCI document states: "In 1999, no test had yet been developed that could detect EPO, so the samples taken during the 1999 Tour de France were not tested for EPO.
"In 2005, samples taken from Lance Armstrong at the 1999 Tour de France were retested in a scientific research programme of the antidoping laboratory of Chatenay-Malabry, Paris.
"According to the research results EPO was found in Armstrong's samples. As indicated by the laboratory, and later also in the Vrijman report, these research results did not constitute valid proof of the presence of EPO under the antidoping rules.
"Until his public confession in an interview with Oprah Winfrey broadcasted on 17 January 2013, Armstrong has always denied that he had ever used EPO."
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