An inverted tooth chain drive system includes an inverted tooth chain structured for inside flank engagement. The chain includes link rows each including leading inside flanks that project outwardly relative to trailing outside flanks of a preceding link row. The system further includes a sprocket with which said inverted tooth chain is drivingly engaged. The sprocket includes a plurality of teeth circumferentially spaced about an axis of rotation, each tooth comprising an engaging flank and a disengaging flank. Some of the teeth are defined with a first tooth form in which said engaging flank thereof is defined with a first pressure angle and others of said teeth are defined with a second tooth form in which the engaging flank thereof is defined with a second pressure angle that is different from the first pressure angle in order to stagger or modulate the initial meshing impacts between the leading inside flanks of the chain and engaging flanks of the sprocket teeth. The sprocket can be optimized for manufacture by a hobbing process, by arranging the different tooth forms in a specific “hob-compatible” pattern.