Benzinga's Volume Losers

A number of notable stocks are moving lower on very heavy volume in Tuesday's afternoon trading session. They include Zillow, Inc.

, Ctrip.com

, Vivus, Inc.

, and CIENA Corp.

. Zillow has lost 5.47% to $30.94 on volume which is running at 414% of the daily average. It is unclear what is leading to the increased activity in the name. Ctrip.com has shed nearly 7% to $23.00 on the day after a disappointing Q4 earnings report. Volume is nearly 4 times above the daily average. Vivus is getting pummeled ahead of tomorrow's FDA advisory panel for the company's obesity drug Qnexa. According to

, the negative sentiment is related to a prediction from

that the panel will vote 10-12 against Qnexa approval. CIENA, Inc. slashed its first-quarter revenue outlook this morning, and the decreased guidance is weighing on shares. At last check, CIEN had fallen 7.76% to $15.68 on 191% of its average daily volume.