Walter Mazzarri's men missed a golden opportunity to halve Juve's six-point advantage at the top when the points were shared from last Friday's 1-1 draw between the two teams at the San Paolo.
But former Bianconeri keeper De Sanctis believes Napoli are unfazed and ready to overcome a run of four straight draws before launching one last assault on top spot.
He told La Repubblica: "Napoli have started doing good things again in the last two matches and on that basis we are very confident going into the rest of the season.
"I wouldn't say we have been stuck in our tracks, just that we've slowed down a little bit. But we are chasing Juve and not looking back."
The Stadio Marc'Antonio Bentegodi has been a particularly unhappy hunting ground for Napoli over recent years, with the southern outfit claiming just one win from their four trips north since reaching the top flight.
"We want to get back to winning ways in Verona and we will try to get the best possible result, although we know it won't be easy," De Sanctis added.
"Going to Chievo has been difficult for us and we've only won once since I've been here. On other occasions we lost or played badly, so this is an important test for us."
Defender Paolo Cannavaro serves a one-match ban at the Bentegodi on Sunday while Miguel Britos' participation remains in doubt due to injury.
Chievo head coach Eugenio Corini is starting to worry that the Gialloblu are running out of time to drag themselves away from danger.
Corini was pleased with his players' performance in a 2-1 defeat at Fiorentina but the Flying Donkeys are facing up to the possibility of a fifth defeat in six games tomorrow.
"In terms of results, the last few games have not gone well," Corini said. "But the fact is that we coped well in a difficult game at a tough place and that should give us the strength to get good results in the future."
Defender Gennaro Sardo is Corini's only injury concern as Chievo bid to avenge October's 1-0 defeat at the San Paolo.