Shares of Nastech Pharmaceutical ( NSTK) sank 6.4% to $13.17 Thursday after the company said it priced a public offering of 3.25 million shares at approximately $13.20 a share.

Novartis' ( NVS) shares sank on preliminary results showing that sales of its eye drug Visudyne, which it co-markets with QLT ( QLTI), fell nearly 29%.

Novartis shares were 2.5% lower to $58.06. QLT's shares were up 4 cents to $8.74 after falling earlier in the day.

Sales of Visudyne as well as OSI Pharmaceuticals' ( OSIP) drug Macugen have taken a hit since the approval of Genentech's ( DNA) eye drug Lucentis in June.

Shares of medical appliance manufacturer Somanetics ( SMTS) plummeted 14.3% to $20.01 after the company announced fourth-quarter revenue that fell short of expectations.

The company earned $5.3 million, or 37 cents a share, in the fourth quarter, including a $3.4 million tax benefit, down from 43 cents a share in the year-ago quarter. While revenue was up 25% to $7.68 million in the quarter, analysts surveyed by Thomson First Call were expecting revenue of $8.94 million.

Shares of Barrier Therapeutics ( BTRX) sank 4.7% to $8.20 after the stock was downgraded to hold from buy by analysts at Roth Capital.

"We prefer to reduce to a Hold rating at this time until further progress is achieved" in the company's research pipeline, wrote analyst Mark Taylor. He maintains a 12-month price target of $9.

Among other health care winners Thursday were Abbott ( ABT), up 2% to $52.58; Schering-Plough ( SGP), 1.3% higher to $24.84; Merck ( MRK), rising 1.2% to $45.53; Barr Pharmaceuticals ( BRL), gaining 3.4% to $54.40; and Vernalis ( VNLS), whose shares jumped 12.5% to $2.70.

Among the losers were Rigel Pharmaceuticals ( RIGL), falling 3.5% to $11.48; Novogen ( NVGN), off 1.3% to $12.01; Arena Pharmaceuticals ( ARNA), down 2.6% to $13.12; Prestige Brands ( PBH), losing 1.2% to $12.73; and Coley Pharmaceutical ( COLY), down 1.8% to 9.81.

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