Shares of Amylin Pharmaceuticals ( AMLN) were among the worst-performing health-related stocks Thursday, falling 11% after the biopharmaceutical company posted third-quarter results that were worse than Wall Street expectations.

The company reported a loss of $69.5 million, or 65 cents a share, on sales of $25.9 million. Analysts surveyed by Thomson First Call projected a loss of 57 cents a share on sales of $30.7 million. A year ago, the company reported a loss of $34.1 million, or 36 cents a share, on sales of $13.4 million. The company posted a big jump in selling, general and administrative expenses during the most recent period. SG&A expenses amounted to $52.1 million, which was up considerably from last year's $15 million. Amylin attributed the surging costs to the commercialization of Byetta and Symlin. Shares were trading down $4.42 to $33.57.

Express Scripts ( ESRX) rose 16% after the pharmacy-benefit manager posted better-than-anticipated third-quarter earnings and lifted its full-year earnings guidance. The company earned $101.7 million, or 68 cents a share, on sales of $3.85 billion. Excluding items, the company earned $100.2 million, or 67 cents a share, topping analysts' estimate of 61 cents a share. A year ago, Express Scripts posted adjusted earnings, which exclude items, of $77.4 million, or 50 cents a share. The company's sales rose to $3.85 billion from $3.77 billion a year ago, shy of analysts' expectation for sales of $3.99 billion.

Looking ahead, Express Scripts now expects full-year adjusted earnings of $2.54 to $2.61 a share, up from its previous guidance of $2.37 to $2.42 a share. Analysts had forecast earnings of $2.40 a share. Express Scripts shares were up $10.14 to $72.21.

Shares of PacifiCare Health Systems ( PHS) rose 1.3% after the company posted better-than-expected third-quarter results. The health insurer earned $118.1 million, or $1.21 a share, on sales of $3.77 billion. After stripping out one-time gains and losses during the quarter, the company would have earned $1.18 a share. Analysts were expecting earnings, before items, of $1.01 a share on sales of $3.67 billion. A year earlier, the company earned $88.2 million, or 94 cents a share, on sales of $3.11 billion.

For the fourth quarter, PacifiCare forecast adjusted earnings of 89 cents to 94 cents a share, above Wall Street's projection of 83 cents a share. The company's shares gained $1.04 to $79.17.

FoxHollow Technologies ( FOXH) dropped 10% after the company posted third-quarter results that were better than expected but issued fourth-quarter sales guidance that fell below expectations. The company, which makes minimally invasive plaque excision devices, posted a third-quarter loss of $1.5 million, or 6 cents a share, on sales of $36.1 million.

Excluding stock-based compensation costs, the company would have reported a profit of $709,000, or 3 cents a share. Analysts were expecting a loss of 8 cents a share on sales of $35.3 million. For last year's period, the company reported a loss of $7.4 million, or $6.83 a share, on sales of $11.6 million. The loss-per-share calculation in the most recent period is based on 23.2 million shares vs. 1.1 million shares a year ago.

FoxHollow forecast a fourth-quarter loss of $700,000 to $1.2 million, or 3 cents to 5 cents a share. Excluding stock-based compensation expenses, the company sees earnings of 4 cents to 6 cents a share, above analysts' mean estimate of 2 cents a share. FoxHollow predicted sales of $40 million to $42 million, compared with Wall Street's target of $42.7 million. Shares were trading down $5.49 to $48.24.

NxStage ( NXTM) rose 18% on its first day of trading as a public company. The medical device company priced 5.5 million shares at $10 apiece, resulting in net proceeds of about $49 million. The price was below the company's proposed range of $11 to $12 a share. Shares were trading up $1.75 to $11.75.

Other health care volume movers included Pfizer ( PFE), up 7 cents to $21.13; Novavax ( NVAX), down 56 cents to $4.36; Johnson & Johnson ( JNJ), down 90 cents to $61.91; Kinetic Concepts ( KCI), down $14.75 to $41.25; Amgen ( AMGN), down 80 cents to $74.40; Merck ( MRK), down 7 cents to $27.12; Bristol-Myers Squibb ( BMY), down 1 cent to $21.70; and Genentech ( DNA), down $1.67 to $87.85.
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