Biotechnology has surged higher in recent months as a combination of good news and speculation lifted the group's well-knowns and unknowns alike, but on a day that sellers took control of the broad market, this superheated sector also took a tumble.

Two broad sector measures reflected the selloff. The Amex Biotech Index ended the day down 4.6%, and the Nasdaq Biotech Index gave up 6.1%.

Individual stocks were hit hard, and one of those feeling the pain most acutely was

Protein Design Labs

(PDLI) - Get PDL BioPharma, Inc. Report

, which fell nearly 11% to $15.35.

Human Genome Sciences


dropped almost 8% to $12.40.


(VRTX) - Get Vertex Pharmaceuticals Incorporated Report

lost 6% to $14.62.

Elsewhere in sector,



fell 6% to $43.48,



shed almost 6% to $14.96, and


(CHIR) - Get Global X MSCI China Real Estate ETF Report

was down 5% to $44.75.

Most of the well-known names in the group were under some degree of selling pressure, including



, off 5% to $43.25, and


(AMGN) - Get Amgen Inc. Report

, lower by 3% to $63.82.



held up relatively well, declining only 0.6%, or 46 cents, to $74.07. Helping support Genentech was

a bullish report from research firm UBS on the stock and the company's prospective cancer treatment Avastin.


(GILD) - Get Gilead Sciences, Inc. (GILD) Report

was off 5% to $51.30, and

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declined 1% to $35.76.

(Adam Feuerstein, a columnist for's

sister site


took a look today at the biotech sector's recent run-up, and he offered some insight regarding just how long the optimism might continue lifting these stocks.)

The smaller-cap names were also seeing their fair share of selling.



was down 11% to $9.01.


(GERN) - Get Geron Corporation Report

lost more than 4% to $6.86, while



slipped 2% to $5.06.

Large pharmaceutical companies headed lower, as well.


(NVS) - Get Novartis AG Sponsored ADR Report

was down 0.6% to $41.60,


(PFE) - Get Pfizer Inc. Report

dropped 1.3% to $35.60, and


(MRK) - Get Merck & Co., Inc. (MRK) Report

lost 1.5% to $62.30. Meanwhile,


(GSK) - Get GlaxoSmithKline plc Sponsored ADR Report

fell 3% to $41.70.

Forest Laboratories


was sent down 12% to $53.29 after the company reported

disappointing data from a recent study involving the company's Alzheimer's treatment. The Amex Pharmaceutical Index declined 2% on the day.