Rita Jeptoo, who set a women’s course record in winning the 2014 Boston Marathon, was suspended by Athletics Kenya for two years for using performance-enhancing drugs.
Jeptoo tested positive for the blood-booster EPO in September, one month before she won the Chicago Marathon for the second straight year.
She has denied doping, calling the accusations “lies,” but her governing organization ruled against her.
“AK followed due process in her matter and it was appropriate that she serves a two-year ban,” AK chief executive Isaac Kamande told Reuters news service.
Jeptoo has won Boston the last two years. She also won in 2006. In 2014 she finished in a record time of 2 hours, 18 minutes, 57 seconds.
The 33-year-old won the 2013-14 World Marathon Majors title but has been denied her share of the $500,000 prize.