In the following video, Motley Fool health-care analyst David Williamson takes investors through one possible boom for Eli Lilly (LLY -2.74%), and one major potential bust. The company does have several major catalysts coming in the near term for drugs in its pipeline aimed both at stomach cancer and diabetes, but will these be enough to counteract losses from a major patent cliff coming up for the company? David gives his opinion on Eli's pipeline, and just how bad the patent cliff could be.