Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Investors of anti-obesity drugmaker VIVUS (NASDAQ:VVUS) witnessed the company getting share-based liposuction, with shares down as much as 26%, following disappointing third-quarter earnings results.

So what: For the quarter, VIVUS' loss nearly quintupled to $40.4 million from $8.6 million in the year-ago quarter as marketing expenses for Qsymia, its anti-obesity drug, have risen dramatically. More damning for VIVUS, sales for the potential blockbuster have limped out of the gate with the company recording a miserable $41,000 in revenue. According to Bloomberg, VIVUS' management notes that patients are simply abandoning their prescriptions of the drug at the pharmacy counter once they realize they're paying the majority of the cost out of their own pockets.

Now what: Talk about a few weeks to forget about for VIVUS shareholders. First, Qsymia was denied approval in Europe by the European Medicines Agency, and now sales of the drug are struggling out of the gate. Part of this can be pointed to its lack of a marketing partner which I pointed out as a serious flaw weeks ago. Arena Pharmaceuticals (NASDAQ:ARNA), my pick to win the lion's share of the anti-obesity market, has partnered with Eisai (OTC:ESALY), giving up some of its potential revenue, but locking in an experienced marketing team. Arena's Belviq also has a chance to lock up EMA approval of its drug and garner the international revenue that VIVUS could not. With few other competitors on the horizon -- let's face it, Orexigen Therapeutics' (NASDAQ: OREX) Contrave is still two years from market even if it breezes through safety trials -- Arena appears poised to take the lead and VIVUS may need to start begging for a marketing partner.

Will VIVUS be left in the dust by Arena Pharmaceuticals? Find out the answer to this question and much more by getting your copy of our latest premium research report on VIVUS. Packed with in-depth analysis on the opportunities and threats facing VIVUS -- and complete with a year of regular updates -- this report will give you the tools you need to make smart long-term decisions. Click here to get your copy.

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