The 28-year-old was provisionally suspended in November 2024 before receiving a four-year sanction from the Athletics Integrity Unit in February 2025 for allegedly using or attempting to use a banned drug.
Ikeda challenged the ruling at CAS in March 2025, rejecting the doping allegations brought by World Athletics, which had alleged blood manipulation based on abnormalities in his Athlete Biological Passport.
The case was heard by a CAS panel in Lausanne in May.
While the panel accepted that several readings in Ikeda's biological profile were abnormal, it found there was a reasonable non-doping explanation for the findings.
CAS said Ikeda supported his case with substantial medical and expert evidence, providing a broader factual basis than was available during the proceedings before the World Athletics tribunal.
The appeal body overturned the four-year sanction, concluding that the anti-doping charge had not been established and that no ban should apply.