Cavani sustained a thigh injury in the 2-0 win over Bordeaux in January and has missed PSG's last two games.
Blanc suggested that the Uruguayan would be out for Les Parisiens' next couple of encounters, tipping the attacker for a return against Toulouse on Feb. 23.
"Edinson Cavani follows his program and should return at the end of next week. All the signs are very good," he told reporters.
Cavani's strike partner Zlatan Ibrahimovic should be fit for both encounters, despite struggling with back problems over the past week.
Former France coach Blanc said that he may reshuffle his team ahead of the encounter with Leverkusen, but is keen to stay focused on his side's domestic title bid.
"Zlatan Ibrahimovic has trained normally for two days without any problems," Blanc said. "He is fit to play and will probably play against Valenciennes. I think it will be a different team from the one that played Monaco. But to prepare for the Leverkusen match, it will not be a bad thing to play against Valenciennes on Friday.
"The second part of the season began in Brest [in the Coupe de France], it does not start against Leverkusen. The championship is important, we must win against Valenciennes tomorrow."