Are micro-dosing riders poking holes in biological passport?

Anti-doping expert Robin Parisotto has stated that although clean athletes can now win Grand Tours, the net needs to tighten around the more sophisticated cheats. The detection of patterns that suggest micro-dosing EPO and blood transfusions in some blood profiles continues to cause a major concern within anti-doping circles.

Parisotto also raised questions over how the UCI previously governed the sport, and has concerns that athletes’ biological passport (APB) data may have been shielded under the governing body’s previous leadership. He finds it surprising that the riders first sanctioned under the passport system in 2009 included no top names. Pointing to the favouritism by the UCI toward Lance Armstrong and Astana, as evidenced in the CIRC report, he makes the uncomfortable suggestion that the anti-doping experts previously weren't getting full access to the UCI's results.

The Australian forms part of the UCI's panel of experts that examine biological passport cases, and he admits that he has seen seismic shifts in the general patterns within biological passport data since the APB’s inception almost a decade ago when wild fluctuations would present almost ‘open and shut cases’ of blood manipulation and or doping.

The recent CIRC report into cycling’s doping culture paints a picture of a cleaner sport today, but with a landscape blighted by doping driven underground, with prevalent abuse of corticoid steroid and therapeutic use exemptions within the peloton.

Passport picture fuzzy under McQuaid

Certainly, the first batch of biological passport cases unveiled by the UCI in 2009 in which five riders - Pietro Caucchioli, Ricardo Serrano, Igor Astarloa, Ruben Lobato Elvira, and Francesco De Bonis - were sanctioned, included no riders who were considered big fish at the time. Astarloa may have won the rainbow jersey in Hamilton in 2003 but by the time his case was announced he was almost unrecognisable in reputation to the one who had performed so well at Saeco.

“The first passport cases were open and shut but the problem, and it’s what we’ve seen from the CIRC report, is that there was so much influence on who was tested and when. I figure most of the cyclists at that time [of the first cases] who were blood doping, escaped,” Parisotto told Cyclingnews.

“You read that report and you think people were watching who was doing what and were then making decisions that had nothing to do with keeping drugs out of sport. The UCI was a tightly run ship, but just not pointing in the right direction.”

“Those first five cases weren’t exactly big names so you have to ask who were they testing and when were they testing them. Us experts don’t know because we don’t know the athletes. I suspect that in 2008 when we first started we weren’t getting the full picture.”

The argument that those instant five were low hanging fruit or ideal cases from which the passport would be built and gain credibility before tackling more challenging cases has been voiced before, but Parisotto’s words echo those of Michael Ashenden, another of the UCI’s experts, who previously raised questions regarding Armstrong’s passport data and the UCI’s handling of his results.

“Under the previous leadership I was concerned that I wasn’t getting access to the full picture in terms of certain athletes and their results. That certain athletes were having their passports scanned by other parties and they wouldn’t go anywhere.”

Despite those concerns Parisotto believes that the governing body, under its new stewardship with Brian Cookson, can sail into calmer, more credible waters. He welcomed the findings in CIRC and added that Cookson can establish a more credible future in the fight against doping.

However while the integrity of the UCI is critical, credibility is only one aspect in the fight against doping. Since the passport’s creation, according to Parisotto, doping has become more sophisticated with micro-dosing of EPO a major concern.

Parisotto has seen fluctuations in several biological passports that are indicative of the use of smaller EPO doses, and he agrees that the parameters by why which passport cases are opened may need to be revised and tightened.

“That’s possibly a fair observation. However, the passport has made it harder to maintain your parameters within a normal range. So much so that the athletes would have to ask if it was worth it, if they were going to get a benefit. The effort that goes into harvesting blood and then storing it isn’t trivial so I would believe that while the passport has reduced it, it hasn’t eliminated it. That’s for sure. It’s still happening.”

Cyclingnews spoke to one rider who raced through the 2000s and at the highest level. His testimony, although he did not want to be named, provides an indication into what a athlete can gain from micro-dosing.

"If you’re training at altitude you can do 3-400 units of EPO every night at 10pm intravenously and be fine by the morning. You’re only required to answer the door to the testers during your one-hour window, so just make it 9am and you’ll be fine. That’s plenty of time. Over two weeks you’ll raise your HCT [haematocrit - the percentage of oxygen-carrying red blood cells -ed.] by 4-5 points but if you’re training hard your blood will be diluted and it won’t show on the test for the biological passport, and that’s conservative.”

“You’re fine with 800-1000 units with that amount of clearance time,” he added. “But then your HCT will rise faster so there’ a very small risk with the ABP. Human growth hormone? You can do as much as you want with an hour of clearance time. That alone will raise your HCT by 3-4 points over three weeks and double testosterone production. Once you’ve raised your HCT 4-6 points you’ve got two months of benefit – decreasing gradually over the second month. For the guy who is around 70kg a 6-8 point increase, which is very easy to manage, you’ve got 20-30 extra watts.”

Such a significant difference in performance could make a drastic impact on the outcome of a race. Cyclingnews spoke to a leading anti-doping expert who did not want to be named and we presented him with the above testimony.

“I think 300-400 units won't achieve much,’ they told Cyclingnews.

“To achieve something you need to be taking 1500-6000 units a week but it’s all within the context of the athlete who will be looking to take things that won’t be detected rather than what’s going to give him the benefit. It’s hard to say where that benefit would come in, perhaps from 800-1000 units per day would see a real increase in haematocrit, I wouldn’t argue with that.”

Holes in the passport?

Trying to ascertain what the perfect window would be for an athlete who is intent on doping appears unclear, therefore. Unsurprisingly, anti-doping experts are not too keen on revealing any holes in their ABP model.

However, a report written by Ashenden and several other respected scientists in 2011 stated that, “at least one evasive tactic (to use small, frequent injections of rhEPO) does not perturb blood variables in a manner that would be flagged as abnormal by the ABP software.”

Ashenden et al used 10 male non-elite athletes for the study, in which they gave one group 10IU/kg of rhEPO twice weekly (more frequent injections might have caused subjects to drop out of the study) for four weeks, and a second group received 20IU/kg for two weeks. Both groups were then given 20IU/kg for four weeks, then 30IU/kg for four weeks, while three subjects ramped up to 40IU/kg for their final three injections.

Each volunteer's blood parameters were evaluated using the ABP Operating Guidelines for analysis and failed to find a change significant enough to be deemed abnormal. One caveat was they did not perform direct testing for rhEPO on the subjects' urine, so they could not say if riders who undertook this strategy would risk testing positive.

"None of the individual OFF-hr values collected from our subjects during treatment with rhEPO were flagged as abnormal by the ABP software,” the report said. "Our findings demonstrate that it is possible to inject rhEPO without triggering Passport thresholds. On one hand, this underlines the need to retain existing analytical procedures in support of the Athlete Biological Passport, and on the other hand, emphasises the need for recruitment of novel strategies to hopefully close current loopholes."

“The passport’s utility as an intelligence-gathering tool should not be understated,” the report concludes.

“Perhaps additional biomarkers, with increased sensitivity but reduced specificity, might be introduced to magnify the passport’s utility as a targeting strategy (low specificity in this setting is immaterial when the data are used only for intelligence gathering).”

Does microdosing give a significant benefit?

Parisotto admits that while the perfect window may exist for potential dopers, in his view the benefits do not outweigh the risks, and that with each athlete, the doses of EPO will vary when in conjunction with the resulting benefit.

“That perfect window may exist but you can’t really generalize because each athlete is different.”

“I don’t know at what point a rider would get a benefit and remain under the radar.

“These days it’s more sophisticated and we are now seeing the small incremental changes. In the past there were these huge quantum leaps in haemoglobin from 14 to 16 and then back again to 14. Now it’s 15, 15.5, 16. That’s evidence that micro-dosing is taking place. I can’t put a number on that but there are many [profiles] that are still suspicious. There are still many out there that are still under observation and that need further expert review.”

“Nowdays you can win big races like Grand Tours by riding clean, but when it comes to the passport cases we make recommendations, such as targeting the athletes, but one of the problems with the passport is that it does take time. If you can confirm or provide stronger evidence then you want that track record of data. It’s frustrating, I know, but that’s what we’re dealing with. It’s not just a drug we’re testing for. It’s a procedure that takes time and the effects on the body are far more subtle.”

In Ashenden’s report in 2011 he and his colleagues support Parisotto’s general position but state that changes and improvements to the passport could be made. However Cyclingnews understands that even though the UCI and the anti-doping experts regularly meet to discuss the strength and weakness of the passport, none of Ashenden’s independent recommendations have been made.

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Daniel Benson

Daniel Benson was the Editor in Chief at between 2008 and 2022. Based in the UK, he joined the Cyclingnews team in 2008 as the site's first UK-based Managing Editor. In that time, he reported on over a dozen editions of the Tour de France, several World Championships, the Tour Down Under, Spring Classics, and the London 2012 Olympic Games. With the help of the excellent editorial team, he ran the coverage on Cyclingnews and has interviewed leading figures in the sport including UCI Presidents and Tour de France winners.