The European Medicines Agency recently handed VIVUS (Nasdaq: VVUS) an official rejection for its obesity drug Qsymia, leading Arena (Nasdaq: ARNA) shareholders to wonder if this creates a major opportunity for the pharmaceutical company's competing drug, Belviq.

While Qsymia and Belviq are both FDA-approved in the U.S., an EU decision on the latter isn't due until next year. Approval on two continents would be a huge win for Arena and its partner Eisai, but that could be easier said than done if the Qsymia rejection is also a signal that weight loss drugs will not face easy approvals in Europe. In the video below, Fool.com analysts Max Macaluso and David Williamson look at several possible scenarios, and discuss how it could ultimately go either way for Arena.