The annual marathon and half-marathon in Austin first partnered with Livestrong in 2010. They had announced in 2011 the partnership would be extended through 2020, the Austin (Texas) American-Statesman reported Wednesday.
The separation leaves the race organizers without a major sponsor. It comes six months after Armstrong, creator of the foundation, was stripped of his seven Tour de France medals and resigned as foundation chairman.
Armstrong, in a January interview with Oprah Winfrey, admitted doping during his career as a cyclist.