This month, Arena Pharmaceuticals (NASDAQ:ARNA) and VIVUS (NASDAQ:VVUS) reported first-quarter earnings, and the results continued to be unimpressive, with both companies' obesity drugs having trouble gaining any traction. Neither drug has broken the $10 million-per-quarter mark, putting them a long way away from their blockbuster potential.

In the following video, senior biotech specialist Brian Orelli and health-care analyst David Williamson discuss why the drugs have struggled despite the large market, noting that there are issues with both patients and doctors that the companies have to overcome.

The duo also discuss Orexigen's (NASDAQ:OREX) Contrave, a potential third player that should hear from the FDA by June 10. Orexigen was vying for approval around the same time as Arena Pharmaceuticals and VIVUS but was delayed because the FDA wanted a cardiovascular safety study performed. Given the sales so far, the delay doesn't seem to have been particularly detrimental to Orexigen.

Brian Orelli has no position in any stocks mentioned. David Williamson owns shares of Apple and Google (C shares). The Motley Fool recommends and owns shares of Apple, Google (A and C shares), and Netflix. Try any of our Foolish newsletter services free for 30 days. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.