Benzinga's Top Pre-Market Losers

Riverbed Technology

dipped 17.46% to $14.47 in the pre-market session after the company reported downbeat second-quarter revenue. Optimer Pharmaceuticals

shares fell 6.47% to $12.43 in the pre-market trading after Cubist Pharmaceuticals

announced its plans to acquire Trius Therapeutics

and Optimer for up to $1.62 billion. BioCryst Pharmaceuticals

shares dropped 5.78% to $3.75 in pre-market trading after the company announced its plans to sell up to $20 million in common stock. Genworth Financial

dipped 3.82% to $12.85 in the pre-market session after the company reported weaker-than-expected second-quarter results.