Kenyan marathon runner Peres Jepchirchir has been provisionally suspended by the Athletics Integrity Unit (AIU) after an out-of-competition sample returned a positive result for EPO, according to the BBC. The sample was given in Kenya before she won the Sydney Marathon on 30 August 2026. The 33-year-old, who holds Olympic and World Championships marathon titles, ran two hours, 18 minutes and 31 seconds to take the win in Sydney.
The provisional suspension was announced on Friday, 23 October 2026, roughly two months after the race.
Why it matters
Jepchirchir is one of the most decorated distance runners of her generation, and a positive test at her level draws attention to how the sport polices its biggest names. She won the women's marathon at the Tokyo Olympics in 2021 and then returned to the same city to claim the world title in September 2025. A provisional suspension means she cannot compete while the case proceeds, and it places her recent results under scrutiny.
The timing also matters because the sample was collected before a race she went on to win. Sydney became the seventh world major marathon in 2025, so her victory there carried added weight on the elite circuit.
What EPO is and how it is detected
EPO, or erythropoietin, is a hormone the kidneys produce naturally. It drives the body to make new red blood cells. When injected, it raises the number of red blood cells in the bloodstream, and those cells carry oxygen to the muscles. That is why it appears in doping cases in endurance events.
According to the BBC, injected EPO can only be picked up in urine or blood for a short period, which makes the timing of testing significant in any case built around it.
A career built on major wins
Jepchirchir's record includes victories across several of the sport's biggest races. Beyond Tokyo and the 2025 World Championships, she won the New York Marathon in 2021, the Boston Marathon in 2022 and the London Marathon in 2024. She also set a women's half-marathon world record in 2017 and broke it again three times in 2020.
In Sydney, she finished more than three minutes ahead of her fellow Kenyan Irene Chepet Cheptai.
The AIU has not indicated a timeline for resolving the case. Jepchirchir remains provisionally suspended, and further steps in the process will determine whether the suspension is lifted or a sanction follows.
