LONDON -- In a dramatic change that could lead to numerous doping cases being thrown out, athletes who tested positive for meldonium might be able to avoid sanctions because of a lack of scientific evidence on how long the recently banned drug stays in the system.
The World Anti-Doping Agency said Wednesday provisional suspensions can be lifted if it is determined that an athlete took meldonium before it was placed on the list of banned substances on Jan. 1.
"It's not an amnesty as such," WADA president Craig Reedie told The Associated Press.
More than 120 positive tests for meldonium have been recorded in various sports and countries, many in Russia, since the drug was prohibited by WADA. The highest-profile case involves Maria Sharapova, who announced last month that she tested positive during the Australian Open in January.
"The fact that WADA felt compelled to issue this unusual statement now is proof of how poorly they handled issues relating to meldonium in 2015," Sharapova's attorney, John Haggerty, said in a statement Wednesday. "Given the fact that scores of athletes have tested positive for taking what previously was a legal product, it's clear WADA did not handle this properly last year and they're trying to make up for it now.
"The notice underscores why so many legitimate questions have been raised concerning WADA's process in banning meldonium as well as the manner in which they notified players. This notice should have been widely distributed in 2015, when it would have made a difference in the lives of many athletes."
Defense lawyer Howard Jacobs, a veteran of numerous high-profile doping cases who is helping represent Sharapova, told ESPN.com it was "too early to say" whether the data released by WADA would affect her circumstances.
Jacobs is working on one other meldonium case for an athlete he would not name because the test result has not yet become public. He predicted that WADA's ongoing study of how long the drug can linger in the system will help resolve many of the pending cases. He said he would "reserve judgment" on whether that research done by the agency's accredited laboratories would be sufficient, or whether athletes would still need to hire their own experts.
Better to have the data late than never, Jacobs said.
"It would have been nice if this would have been done six, eight, 10 months ago," he said. "That would have saved everyone a lot of grief. Hopefully, this will guide [WADA] in the future."
Some athletes who have tested positive have claimed meldonium remained in their systems for months even though they stopped using it last year. Sharapova did not specify when she had last used meldonium.
Some sports federations pressed WADA to address the issue and advise how they should proceed in dealing with meldonium cases.
The Latvian-made drug, which is typically prescribed for heart conditions, was widely used as a supplement by athletes in Eastern European countries. The drug increases blood flow, which improves exercise capacity by carrying more oxygen to the muscles.
In a notice to national anti-doping agencies, WADA acknowledged that "there is a lack of clear scientific information" on how long it takes for meldonium to clear the system.
While several studies are currently being carried out by WADA-accredited laboratories, preliminary results show that long-term excretion of meldonium can take weeks or months, WADA said.
As a result, it is possible that athletes who took meldonium before Jan. 1 "could not reasonably have known or suspected" that the drug would still be present in their bodies after that date, WADA said.
"In these circumstances WADA considers that there may be grounds for no fault or negligence on the part of the athlete," the statement said.
Reedie said the notice was sent out to all national anti-doping bodies on Tuesday and would be posted on the agency's website on Wednesday. The notice was released earlier Wednesday by Russia's anti-doping agency.
"It is designed to explain the science that we know," Reedie told the AP in a telephone interview. "The issue that it deals with is the time this drug takes to come out of the system. It's an attempt to clarify the many questions that we've been asked."
The Russian sports ministry and national Olympic committee welcomed the WADA statement, and the country's officials suggested there could be a mass amnesty of Russian athletes.
Russian tennis federation head Shamil Tarpishchev told the R-Sport agency he hoped that Sharapova would be able to play at the Olympics in Rio de Janeiro in August, and the head of the Russian swimming federation suggested there could be a swift return to competition for suspended world champion Yulia Efimova.
"In no way does this serve as an 'amnesty' for athletes that are asserted to have committed an anti-doping rule violation," WADA spokesman Ben Nichols told the AP in an email. "Rather, it serves as guidance for how anti-doping organizations should assess the particular circumstances of each individual case under their jurisdiction."
The meldonium cases have no bearing on the ongoing suspension of Russia's track and field team following a WADA commission report into what it called state-sponsored doping.
Sharapova, a winner of five Grand Slam titles, said she had been taking meldonium for medical reasons over a 10-year period and had not seen a WADA notice last year that the drug would be banned starting in 2016.
Sharapova was provisionally suspended by the International Tennis Federation pending a disciplinary hearing.
"We can confirm that the case is ongoing and that there will be a hearing," ITF spokesman Nick Imison told the AP on Wednesday. "I have seen the statement from WADA, and obviously any ongoing cases will take that information from WADA, but it won't affect the fact that there is an ongoing case."
WADA said prosecution of meldonium cases can be "stayed" and provisional suspensions lifted if the concentration of the drug in the system is between 1 and 15 micrograms per millileter and the test was carried out before March 1, or if the level is below 1 microgram per millileter and the doping control was conducted after March 1. In both cases, the drug could still be in the athletes' system from before Jan. 1.
The agency said doping cases should be pursued, however, in the case of athletes who admit having taken meldonium on or after Jan. 1. The same applies to cases where the concentration of the drug is above 15 micrograms per millileter and where the level is between 1 and 15 and the drug test was after March 1.
Meldonium cases promise to be complex even by the standards of the often-confusing world of doping jurisprudence.
A finding of "no fault" is still technically a rules violation, but wouldn't count in the event that athlete committed another, more serious violation. (A second offense can trigger a lifetime ban.) Athletes who tested positive for trace amounts of meldonium in competition could have their results disqualified even if their suspensions are lifted.
Decisions on whether to lift provisional suspensions will be up to each international sports federation or anti-doping agency hearing the cases, which cross many sports, and there's no guarantee those decisions will be consistent.
Marjolaine Viret, a Swiss sports lawyer who specializes in scientific issues in anti-doping, said the timing of the research might not have been ideal but welcomed its content.
"I have been pleading for some time for the anti-doping movement to be more proactive when it comes to doing research and providing scientific data also when the data supports an athlete's defense, and I think on the whole this notice rather goes into the right direction,'' Viret wrote in an email.
"The question is not so much whether WADA should have acted differently to prevent all these positive cases from being reported as positive, but why a whole athlete group appears to have been using a drug that is designed for specific medical indications."
Information from ESPN's Bonnie D. Ford and The Associated Press contributed to this report.