The TextOnPath property returns the EffectTextOnPath object for fitting text to a path.
Examples:
The following VBA example sets the distance between the text and its path to 1" for each object with text fit to a path on the active page.
Sub Test()
Dim s As Shape
Dim e As Effect
For Each s In ActivePage.FindShapes(Type:=cdrTextShape)
For Each e In s.Effects
If e.Type = cdrTextOnPath Then e.TextOnPath.DistanceFromPath = 1
Next e
Next s
End Sub