The move ends a 15-year relationship between UIP - which distributes films under the Paramount Pictures, Universal and Dreamworks banners - and the WPP-owned Mediaedge:cia.
Mediaedge: cia inherited the account via The Media Edge following last year's merger.
The media auditing company Billetts oversaw the review, which was called in September. MediaCom was also invited to pitch.
The news is a blow to Media-edge:cia - it has consistently produced effective work for the client and at last week's Campaign Media Awards the agency won a commendation for its work on the Jackass: The Movie campaign.
"I'm very disappointed but have managed costs so that it will have a minimal impact on our staff, all of whom have done such great work for UIP over the years," Rob Norman, Mediaedge:cia's chairman, said.
ZenithOptimedia's managing director, Gerry Boyle, led the successful pitch. The agency takes on the account from the beginning of next year in time for new releases including Pay Check, starring Uma Thurman and Ben Affleck, and School of Rock, featuring John Cusack.
The UIP win becomes the second film distributor to be handled by ZenithOptimedia - it already looks after EFD.