[1] He returned to the Central African Republic and established a pediatric service at the National Hospital in Bangui.
On 25 October 1993, shortly after Ange-Félix Patassé became president, he appointed Mandaba to the position of prime minister.
He was forced to resign as prime minister in April 1995 to preempt a threatened vote of no-confidence in the government following accusations of corruption and incompetence.
[1] After attending a dinner to celebrate the first anniversary of Patassé's second term on 21 October 2000, Mandaba suddenly felt sick and died at home of a heart attack.
This led to accusations from Mandaba's family and from the youth movement Flambeau centrafricain (FLAC) that Patassé had them poisoned because they were suspected of planning a coup.