Australia's Peter Bol has been cleared of doping. Photo: AFP
Bol, who narrowly missed bronze when he finished fourth at the 2020 Tokyo Olympics, returned a positive result for performance-enhancing Erythropoietin Receptor Agonists (EPO) in January.
He was suspended from all competition, but a later analysis of his B-sample returned an "atypical finding", meaning it did not confirm the original test.
The Sudan-born athlete, who always claimed innocence, has now been cleared, with further testing at a World Anti-Doping Agency-accredited laboratory confirming a negative result
"As a result, Sport Integrity Australia has taken the decision not to progress an anti-doping rule violation for this sample," the anti-doping agency said. "The investigation into this sample is finalised."
Bol said he had been "exonerated" and would now focus on the World Athletics Championships in Hungary later this month.
"It was a false positive like I have said all along," he said.
"The news from Sport Integrity Australia today was a dream come true. No one should ever experience what I have gone through this year."
WADA said it was satisfied that Sport Integrity Australia followed all applicable processes, but would conduct a review nevertheless.
"While we have no reason to question the validity of the analytical method used for recombinant EPO, WADA will assess the current review process in light of the particularities of this case," it said.
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