It's a day that Arena Pharmaceuticals investors have long, long waited for: Obesity drug Belviq is now on the market. 

The company had a seemingly endless wait for DEA scheduling, ultimately receiving class 4 status. In the meantime, competitor VIVUS got its obesity drug Qsymia approved and into patients' hands. 

In this video, health-care analyst David Williamson checks in on the obesity-drug wars, where things stand between Arena and VIVUS, and what Arena investors should look out for given some of Qsymia's initial challenges.

David Williamson has no position in any stocks mentioned. Follow David on Twitter: @MotleyDavid.

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