Teva Pharmaceuticals (TEVA 0.43%) is not only one of the biggest generic drug manufacturers in the world but it also sells Copaxone, the branded blockbuster multiple sclerosis treatment. Despite this unique business model, the company has struggled to gain investor confidence over the last few years. It's facing a number of headwinds; the clock on Copaxone's market exclusivity is ticking fast; and new competitors in the multiple sclerosis space, such as Biogen's (BIIB -0.23%) recently launched drug Tecfidera, are another threat to this drug's sales.

Today, Teva's future is even more uncertain after its CEO announced his resignation. In the following video from The Motley Fool's health-care show, Market Checkup, analyst Max Macaluso discusses the details behind this move and what lies ahead for the company.