Eli Lilly (LLY -2.40%), one of the biggest drugmakers in the world, continues to face headwinds as two of its top-selling pharmaceuticals are set to lose patent protection this year. However, one of its billion dollar blockbusters from 2012 --the antipsychotic drug Zyprexa -- has already lost patent protection. How has this expiration affected Eli Lilly's total business, and are there any parallels to one of its competitors in this space, beleaguered pharma company AstraZeneca (AZN -0.31%)? Health care analyst Max Macaluso dives into this issue in the following video.