Germany’s Marcel Kittel of Project 1t4i was second with Britain's Adam Blythe, 22, next to him in third.
Omega-Pharma Quick Step’s Chicchi, 31, took his fifth victory of 2012, adding to this week's Nokere Koerse title, a stage one victory at the Driedaagse van West-Vlaanderen earlier this month and a Tour de San Luis double.
It is BMC Racing Team rider Blythe’s first podium of the season.
The day's action was marked by an early escape by 15 riders, which steadily shortened to a final four, with Dutchman Kai Reus suffering a heavy fall and hospitalised with facial injuries.
But they were caught with 5km of the 195km course remaining, with Chicchi showing the same powerful finish that saw him win on Wednesday.