Neither Inter Milan or Napoli have been able to make a breakthrough in an evenly contested 45 minutes at the San Siro.
Joel Obi tried his luck with a couple of speculative long-range strikes early in the game, the latter of which drifted just wide of the post from 25 yards.
Napoli were pushed onto the back foot for long periods of the first half as Inter dominated the possession statistics.
Mauro Icardi was proving to be a constant threat for the hosts in attack, and he was agonisingly close to breaking the deadlock with a header which flew inches wide of the target.
Napoli created a rare chance with a patient piece of build-up play, but Marek Hamsik was denied by the outstretched hand of Samir Handanovic after finding space on the edge of the box.
Inter would come closest to breaking the deadlock five minutes before the interval when Hernanes rattled the post with a powerful strike.