James Kibet, 32, was banned for four years for the presence and use of a prohibited substance, Norandrosterone.
In addition to the ban, which is backdated to December 4, 2019, all Kibet’s results since November 1, 2019 have been disqualified.
Meanwhile, former Hamburg marathon bronze medalist Jacob Kendagor, 36, was banned for a similar period for failing and/or refusing to submit to testing.
The Court of Arbitration for Sport (CAS) overturned a decision by the Disciplinary Tribunal in October 2019 to dismiss charges of failing anti-doping tests against Kendagor.
In July that year, Kendagor was forced to stay out of competition for an initial period of two years after he failed to submit or avail himself to World Anti-Doping Agency (WADA) officials to conduct the tests on him.
The AIU, at the time, vowed to appeal against the Tribunal’s decision.
CAS added that all competitive results obtained by Kendagor between November 21, 2018 and October 22, 2019 shall be disqualified, with all the consequences including forfeiture of any medals, points and prizes.
In addition to that, Kendagor was ordered pay to world athletics’ governing body CHF 1,000 (just over $1,000) toward its legal fees and expenses incurred in connection with the case.
Kenya is home to some of the greatest road runners in the world, however, in recent years, it has developed one of the worst doping records.
Athletics Kenya, the sport’s governing body in the country, has previously vowed to take stern action against athletes involved in doping with President Jackson Tuwei saying all athletes implicated will not represent Kenya again in any competition.