MOSCOW • Athletes who tested positive for meldonium before March 1 could have their suspensions overturned less than four months before the Rio de Janeiro Olympics, after the World Anti-Doping Agency (Wada) said it was unable to establish how quickly the drug, outlawed since Jan 1, cleared the system.
Wada's notice to national anti-doping bodies is expected to have a major impact on many of the 120-plus athletes who have tested positive for the performance-boosting drug since January.
They include five-time Grand Slam tennis champion Maria Sharapova, who was among 40 Russian athletes to test positive for the drug after it was added to Wada's list of banned substances in January.
Wada said there was "currently a lack of clear scientific information on excretion times".
"As a result it is difficult to know whether an athlete may have taken the substance before or after Jan 1, when it became illegal.
"In these circumstances, Wada considers that there may be grounds for no fault or negligence on the part of the athlete," it said in a statement sent to anti-doping agencies and sports federations, adding that the presence of less than one microgram of meldonium in the samples was acceptable.
The anti-doping body's notice also gave hope to athletes who have tested positive for the drug since March 1, depending on studies being carried out to determine how long it stays in the body.
Sharapova, who said she had been taking meldonium for more than a decade because of health problems, was provisionally suspended by the International Tennis Federation (ITF) in March after announcing she had failed a test at the Australian Open in Melbourne.
Russian Tennis Federation president Shamil Tarpishchev said the ban could be addressed in a meeting with ITF head David Haggerty later this month.
"The situation with Sharapova could be resolved after April 21 when we meet with the head of the international federation. After that all should become clear. It is too early to talk about Sharapova competing at the Olympic Games," Russia's Tass news agency quoted Tarpishchev as saying.
Russian Sports Minister Vitaly Mutko welcomed Wada's decision.
"The Russian Sports Ministry supports and welcomes the decision made by Wada because it has shown a willingness to understand the situation, rather than stick to the rulebook," he said.
"Wada has demonstrated impartiality and being objective in the fight against doping."
Alexei Kravtsov, president of the Russian Skating Union (RSU), said that five-time world champion Pavel Kulizhnikov and 2014 Olympic short-track gold medallist Semen Elistratov - both found to have taken meldonium - should be allowed to compete again after the Wada decision.
"These sportsmen should be allowed to fall under the amnesty due to the amount found in their doping tests," Kravtsov was quoted as saying by the R-Sport news agency.
Two more Russian federations - rugby and cycling - said their athletes who had tested positive could be free to return to competition.
They include rugby player Alyona Mikhaltsova and cyclists Anastasia Chulkova and Pavel Yakushevsky, who all tested positive for less than one microgram.