The American sportswear brand had initially backed Alberto Salazar, who coached Sir Mo Farah to four Olympic gold medals, after the US Anti-Doping Agency (USADA) findings.
The decision to close the Nike Oregon Project, where Sir Mo trained from 2011 to 2017, comes ahead of Sunday’s Chicago Marathon where the British running star will be defending his title.
Salazar, a celebrated distance runner who launched the Oregon Project in 2001, is appealing his ban for doping violations, including trafficking and tampering.
A memo from Nike CEO Mark Parker, seen by Runners World, said: “This situation, along with ongoing unsubstantiated assertions, is a distraction for many of the athletes and is compromising their ability to focus on their training and competition needs.
“I have therefore made the decision to wind down the Oregon Project.”
Nike will help athletes find new training arrangements, Parker said in the memo, adding that no evidence had been found that performance-enhancing drugs were ever used on Oregon Project athletes.
Speaking after the conclusion of the USADA investigation, Sir Mo, who is not accused of any wrongdoing, said he had “no tolerance for anyone who breaks the rules”.
He parted ways with Salazar in 2017.
Salazar, 61, is unable to coach during the appeal process.