 He held various posts at Elf-Congo from 1985 to 1997.Under President Denis Sassou Nguesso, Itoua was appointed as Adviser to the President for Hydrocarbons, Mines, Energy, and Hydraulics in 1997, and he was additionally appointed as Director-General of the National Oil Company of Congo ("Société Nationale des Pétroles du Congo", SNPC) in April 1998.He was also appointed as a member of the administrative council of "Hydro-Congo", the Congolese oil exploration and exploitation company, on 31 December 1999.