Diabetes drug Januvia has been a boon for Merck (NYSE:MRK) in recent years, and its massive year-over-year growth was one way the company was able to offset the  huge losses incurred by Singulair's recent patent expiration. Recently, however, a study published in JAMA Internal Medicine showed that patients on Januvia and a different diabetes drug -- Byetta, which is jointly marketed by Bristol-Myers Squibb (NYSE:BMY) and AstraZeneca (NYSE:AZN) -- are more at risk of developing pancreatitis.

The risk of pancreatitis with these drugs was already known to a certain extent, and, despite this study, it doesn't seem likely these drugs will be pulled from the market -- but what would happen if they are? Focusing just on Januvia, how dependent has Merck become on this drug? Health care analyst Max Macaluso discusses this situation in the following video.