The head of the French anti-doping agency (AFLD) Pierre Bordry confirmed that Riccardo Ricco, Moises Duenas and Manuel Beltran all tested positive at the Tour de France for CERA, the third generation form of Erythropoietin (EPO).

 

CERA or Continuous Erythropoiesis Receptor Activator is a new form of EPO, created by the Swiss company Roche, that has been created to help dialysis patients or people with kidney problems.

 

The drug stimulates the kidneys to produce EPO which in turn stimulates the bone marrow to increase the creation of red blood cells.

 

More red blood cells allow the body to carry more oxygen and so increases an athlete performance.

 

CERA, or Mircera as it is known commercially, has been approved for medical use in Switzerland and Australia and is close to final approval across Europe .

 

CERA offers benefits over older forms of EPO - for which a test was developed in 2000 - because it is has a slower release rate or creation of red blood cells in the body.

 

For patients that means fewer injections, perhaps even just once a month, and lower health care costs for hospitals.

 

For athletes it means they can take the blood booster less frequently and so reduce the risk of being caught because EPO is difficult to detect a few days after it has been injected.

 

Before the start of the Tour, rumours circulated that some cyclists were using an allegedly undetectable variant of EPO.

 

According to the French Anti-Doping Agency, a urine sample provided last week by Riccò after the fourth stage of the Tour  in Cholet contained metabolites of synthetic EPO as well as evidence of the new substance.

 

The positives seem to indicate the anti-doping agencies are not as far behind the cheats as they have been previously.

 

Britain's Mark Cavendish, who won a record third stage of the Tour today, said: "I think in any aspect of life, you're going to get people who think they are cleverer than the system.

 

"I'm in a sport that I love and I've grown up loving.

 

"I don't want to see it tarnished, and I know the majority of riders feel the same way I do.

 

"I think the people who resort to doping don't have the passion I have and that others have."

 

Meanwhile, Coe said that he would not allow doping to overshadow the 2012 Games.

 

The London chairman said: "Drug cheats can never be allowed to be the large part of the story.

 

"The largest part of the story is the 99 per cent of competitors who openly understand that competition is about fair, open endeavour.

 

"They understand the most talented, the hardest working and the ones with the best coaches and the smartest sports administrators make it to the top.

 

"There is no room for seedy chemists sitting in laboratories trying to figure out how to subvert that process."

 

"Most people see these as two separate issues, the Games is fundamentally about national spirit, the belief that sport matters and the intrinsic values of sport are fundamental - 99 per cent of the athletes and 99 per cent of the population get that.

 

"Of course we take very seriously the need to deliver a Games in a drug-free, zero-tolerance environment.

 

"That is exactly what we will be aiming for over the next four years."