The bomb exploded by a roadside in Bakakhel area of Bannu bordering volatile Miran Shah in North Waziristan Agency, killing two officials of health department on the spot and injuring three others.
A police official said that the minister's motorcade was on its way back from Bakakhel when a remote device hit one of the vehicles in the motorcade.
Durrani was unhurt as his vehicle had already cross the spot, police said.
Police cordoned off the area and started search operation for the arrest of the perpetrators.