Gerald Vinsonneau will head the prosecution of 10 people in a trial which starts on Monday and is expected to last up to three weeks.
The Festina case, which rocked the 1998 Tour de France, has become the biggest doping scandal in cycling's history.
The entire team were kicked out of the Tour after 40 bottles of doping products, mainly the stamina-boosting hormone erythropoietin (EPO), were found in a team car.
But the focus of the trial is likely to fall on Virenque, the Festina team leader in 1998, who has always denied taking performance-enhancing drugs.
Virenque is charged with helping and inciting the administration of illegal doping subtsances to other riders.
He could be sentenced to up to two years in jail and fined up to 100,000 French francs if found guilty.
"Everyone should stick to their positions unless Bruno Roussel and Willy Voet give new elements away," Vinsonneau told Reuters news agency.
Drug taking
Roussel told the police that he and team doctor Erik Rijkaert had overseen doping within the team to limit the damage on riders.
In a best-selling book, Voet revealed details of the doping practices and accused Virenque of drug taking.
Vinsonneau admitted the prosecutors' office had been in favour of dropping charges against Virenque.
"I had asked for the charges to be dropped. Like French Cycling Federation president Daniel Baal and French Cycling League president Roger Legeay, I felt that the evidence against Virenque is insufficient," he added.
Virenque's lawyer Eric Hermmerdinger confirmed his client would be pleading not guilty.
"Richard has nothing to do with the charges against him.
This is not Virenque's trial, this is not a trial which should tell whether or not he's taken EPO," he said.
"He is charged with helping the defendants in the case.
There is no proof that he helped them. Far from it," he added.
Meanwhile, lawyers in the northern French city of Lille have heavily criticised the preparations for next week's trial.
"We are shocked by the size of the means deployed in the Festina case and the colossal difference between showbiz justice and the poverty of everyday justice," said Denis Lequai, president of the Lille bar association.
Demonstration
The lawyers complained that the court had spent vasts sums of money on air conditioning and renovating bathrooms in anticipation of 100 foreign journalists.
The lawyers plan to hold a demonstration Monday in front of the court to express their displeasure.
The trial will be held in a magistrate's court and is expected to last up to three weeks attracting worldwide attention.