By CARL T. HALL
San Francisco Chronicle
August 26, 2005
But the scientists also note that any test result is suspect if samples are mishandled and protocols violated. In Armstrong's case, it's anybody's guess whether sound procedures were followed.
L'Equipe, a French sports newspaper, reported Tuesday that Armstrong, the famed seven-time winner of cycling's elite Tour de France, cheated to win his first Tour in 1999. The paper claimed that tests of six frozen urine samples taken at the time of the race, and traced by the newspaper back to Armstrong, had tested positive last year for the blood-oxygen booster known as EPO.
Armstrong has insisted he never used performance-enhancing drugs. He told reporters he was considering legal action to counter the latest accusations and damning comments from Tour de France director Jean-Marie Leblanc.
It may take a judge or jury to make the final call. Interviews with scientists and other technical experts, however, suggest the test itself might not be the critical issue.
EPO is shorthand for a protein drug called erythropoietin. It was one of the first biotech drugs, a blockbuster developed in 1983 by scientists for Amgen Inc., based in Thousand Oaks, Calif., and approved in 1989 for treatment of anemia in patients with end-stage kidney disease.
The drug is a gene-spliced mimic of a natural hormone produced by the kidneys that stimulates production of red blood cells in the bone marrow. By all accounts, it has been widely misused by endurance athletes trying to gain an edge in competition.
Red blood cells transport oxygen through the body. In long-distance cycling, boosting the blood's oxygen-carrying capacity gives competitors a big edge, similar in effect to training at high altitudes, which stimulates the body's natural blood-forming system.
Because this natural system has essentially the identical effect as the drug's recombinant DNA form, sport anti-doping authorities had a hard time detecting EPO. Initially, they had to rely on blood tests alone, looking for an abnormally high red blood cell count. But that couldn't actually prove doping.
The urine test was developed in time for the 2000 Olympics in Sydney. Details were published in the science journal Nature in June 2000 by Francois Lasne and Jacques de Ceaurriz of the French national anti-doping laboratory.
They described using urine samples from the 1998 Tour de France to hunt for the telltale molecular evidence of the EPO drug, which has been shown to pass intact into the urine, where it remains at detectable levels for hours or days after injection into the bloodstream. Testing at that stage was done only for research, not enforcement.
The test takes advantage of the fact that manufactured hormone, which is made in hamster ovary cells, carries with it sugar molecules that differ from the naturally produced hormone. When the sample is drawn through a special gel by means of an electric current, and then imaged, the natural EPO creates a pattern of horizontal bands that is strikingly different from the pattern produced by the synthetic hormone.
In effect, the pattern is a molecular fingerprint of the drug.
Dr. James Stray-Gundersen, a surgeon and sports-physiology expert now at the University of Utah, was working for Norwegian anti-doping authorities in collaboration with Lasne when the test was being developed. During an interview Thursday, Stray-Gundersen said he had no doubt as to its reliability.
Athletes in recent years may have figured out masking tricks to disguise drug use or have learned when to quit taking EPO to make sure it clears the urine before in-competition testing. But like the test itself, such techniques didn't exist in 1999.
"Nobody back then knew how to beat the test," Stray-Gundersen said. "If they ran the test on these frozen samples and saw these multiple bands (denoting synthetic EPO), that would be pretty damn good evidence."
He recalled collecting urine samples from 22 Norwegian athletes for a clinical test in which 15 were injected with EPO three times a week for seven weeks while seven other athletes were given saline injections as a control.
Lasne analyzed the urine samples, which were taken at varying times after the injections. In 14 of the 15 athletes who got the drug, the test detected its presence. One athlete never tested positive, and some tested positive only after a delay of several days.
But in no case was there a false signal of the drug when it wasn't there, the researchers discovered.
"We never saw a false positive in the placebos," Stray-Gundersen said. "It's there or it's not. This is why there are no false positives - you have to have the band patterns of the recombinant form."
Of course, that doesn't mean Armstrong was guilty in 1999.
The frozen samples reportedly were tested last year only for research purposes and identified only by an anonymous numbering system. The French newspaper said its reporters were able to track the numbers on the six samples back to Armstrong, but there is no independent evidence to verify that was done.
Stray-Gundersen noted that researchers routinely doctor urine samples to hone testing procedures.
Given Armstrong's fame, it's also possible that someone may have spiked samples for not-so-legitimate reasons.
"It's not necessarily the case that funny stuff happened, but there's that possibility, and motive," Stray-Gundersen said. "I don't intend to defend Lance, but the whole thing has been gone about the wrong way here. This sort of puts an asterisk behind his entire cycling career, and I don't know that I buy that."
Armstrong, a cancer survivor, was given EPO therapeutically during his recovery in 1996. But medical experts said there's no chance that could account for a positive test in 1999.
"The actual time it stays in the body is only about a day, maybe two at the most," said Peter Ambrose, a professor of clinical pharmacology for UCSF who serves as a drug-testing crew chief for the NCAA. "The half-life is relatively short - six to 12 hours."
Nor is frozen storage a big issue. Experts said that even if the top of a specimen container was somehow opened in the freezer, the only effect would for some of the water to be lost - protein products would remain behind.
"Many drugs are very stable in urine when frozen for many years," Ambrose said. "One of the reasons urine is such a good medium for drug testing and storing is there are very few active proteins and enzymes in urine that degrade the drug. So drugs tend to be very stable in urine."
Distributed by Scripps Howard News Service, www.shns.com
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