Arena Pharmaceuticals, Inc. (ARNA)

[mick]

Arena Pharmaceuticals (NASDAQ:ARNA)
Arena Pharmaceuticals was once a high-flying stock. Its share price skyrocketed in 2012, after the FDA approved its weight-loss pill, Belviq. But it's had a tough time selling the drug. Despite being on the market for three years now, net product sales were only $4.9 million last quarter.

This disappointing sales performance weighed heavily on the company's share price, which has been in free-fall ever since Beviq was first approved. In the past year alone, shares shed nearly half of their value.