In the following video, Fool contributor Maxxwell Chatsko examines what AbbVie (ABBV -0.48%) investors should expect when Humira comes off patent in the next several years. He discusses how this patent cliff will differ from the steep cliffs traveled by Pfizer (PFE -1.17%) with Lipitor and Bristol-Myers Squibb (BMY 1.07%) with Plavix. However, he also cautions investors to expect sales to fall dramatically with several generic versions currently under development. Nonetheless, there are key differences that should aid AbbVie and its investors transition to a future without Humira.