IMHO, a 15% drop is way too much.
The catastrophe that would cause VRX to go back 15% is a bear market.
Given that a bear market is not on the horizon; IMO a 15% drop in VRX is not where you should stop out of your position. That is where you should double down on your position.
At this point I think it is reasonable for VRX to trade around the $16.50 to $17.50 area as it did last July.