The Court of Arbitration for Sport (CAS) upheld an appeal by Japanese race walker Koki Ikeda against World Athletics, clearing the Tokyo Olympic silver medallist of an anti-doping rule violation and making him immediately eligible to compete again.

The 28-year-old was provisionally suspended in November 2024 before receiving a four-year sanction from the Athletics Integrity Unit (AIU) in February 2025 for allegedly using or attempting to use a banned drug.

Ikeda was not allowed to participate in the Japan Race Walking Championships in February 2025, and all his competitive results between June 20, 2023 and November 1, 2024 were disqualified.

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.

Ikeda placed second in the 20km event at the Tokyo Games as well as at the World Championships in Eugene in 2022. He finished seventh at the 2024 Paris Olympics.

Ethiopia’s Aga handed six-year doping ban

Ethiopian marathon runner Ruti Aga, winner of the 2019 Tokyo Marathon, was given a six-year ban for the presence or use of the prohibited substance methylprednisolone and tampering with evidence, the AIU said on Thursday.

The AIU said Aga, 32, received a two-year ban after testing positive for methylprednisolone, a prohibited steroid that can reduce pain and fatigue and aid recovery, after winning a half marathon in China in March.

It added four years to the ban after finding she had misled investigators during an interview and submitted a fake prescription to justify her use of the substance.

Aga has been provisionally suspended since September 10, with the ban running from that date.

She has finished second three times and third twice at World Marathon Majors.