There's never a shortage of losers in the stock market.

Let's take a closer look at five of this past week's biggest sinkers.

Company

April 13

Weekly Loss

My Watchlist

ViroPharma (Nasdaq: VPHM) $22.01 (27%) Add
InterMune (Nasdaq: ITMN) $11.40 (25%) Add
Nokia (NYSE: NOK) $4.02 (21%) Add
OPNET Technologies (Nasdaq: OPNT) $22.93 (20%) Add
ClickSoftware Technologies (Nasdaq: CKSW) $10.46 (17%) Add

Source: Barron's.

Shares of ViroPharma took a hit on the inevitability of approved generics storming the market to decimate its flagship drug.

InterMune fell after a few analysts downgraded the biotech. Delays with the European launch of its anti-lung-scarring treatment are forcing Wall Street pros to curb their enthusiasm.

Nokia dropped like a lost call after warning that its business isn't doing so well. It's hard to make a good impression when the company is telling investors to expect negative operating margins out of its flagship mobile handset unit.

OPNET also took a hit. The provider of network performance management solutions hosed down its fiscal fourth quarter performance, talking down both its top- and bottom-line targets. OPNET claims that purchasing delays during the quarter that ended in March will be fulfilled this month, but investors aren't so sure.

ClickSoftware didn't click with bulls last week. The enterprise software company warned that it would come up short on the top line in its latest quarter. ClickSoftware is leaving its full-year outlook intact, but investors always worry more about the near-term shortfalls.

Ready for a bounce
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