VIVUS gained approval from the Food and Drug Administration for its obesity drug Qsymia this summer, and its stock is up approximately 80% since the beginning of 2012. This has been a solid return for shareholders, but there are still many questions:

  • How much higher can VIVUS go?
  • Will Qsymia become a blockbuster drug?
  • Will sales decline when Arena Pharmaceuticals' drug Belviq becomes available in early 2013?
  • Will Orexigen’s drug Contrave gain FDA approval and prove to be the dominant player in the obesity drug market?

While these questions may be difficult to answer, investors can make better investing decisions if they understand some of the science behind VIVUS' drug. In this video, health care analyst Max Macaluso discusses what Qsymia is on a molecular level and notes a few things that all VIVUS investors should be watching.

Arena, VIVUS' major rival in the obesity drug market, is confronting significant challenges as it prepares to launch Belviq in 2013. In our brand new premium research report on Arena Pharmaceuticals, senior biotech analyst Brian Orelli walks investors through both the opportunities and threats facing the company. Since key news can develop quickly, we're also including a full year of updates for those who sign up. Click here now to learn more.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.