Shares of UnitedHealth Group ( UNH) were among the best-performing health-related stocks Friday, rising 4% after the company turned in third-quarter earnings that were better than expected.

The health insurer posted earnings of $842 million, or 64 cents a share, on sales of $11.32 billion. Analysts polled by Thomson First Call were expecting earnings of 63 cents a share on sales of $11.33 billion. A year earlier, the company earned $698 million, or 52 cents a share, on sales of $9.86 billion.

Looking ahead, UnitedHealth forecast 2005 earnings of $2.48 a share and 2006 earnings growth of 15% or more. "Our business outlook is favorable," the company said. "The continued strategic and operating advances we are making, combined with strong organic growth now being realized as each of our businesses expands their market share, will drive positive performance into 2006." Analysts project 2005 earnings of $2.47 a share and 2006 earnings of $2.93 a share. UnitedHealth shares were trading up $1.98 to $56.18.

Medarex ( MEDX) rose 3% after the company and its partner filed an application with the Food and Drug Administration to begin testing for their investigational treatment for lupus. Medarex and MedImmune ( MEDI) said their drug, MEDI-545, is a fully human antibody that is believed to target multiple interferon-alpha subtypes. "Preclinical data indicate that MEDI-545 may suppress the abnormal immune activity associated with lupus by binding to the pattern of multiple interferon-alpha subtypes seen in the serum of lupus patients," MedImmune said. As part of the collaboration, which the two companies began in November 2004, MedImmune is responsible for all ongoing development activities. Shares of Medarex recently traded up 25 cents to $8.31, while shares of MedImmune rose 43 cents, or 1%, to $32.80.

Shares of Boston Scientific ( BSX) fell 1% after the medical device company posted third-quarter results that fell short of Wall Street expectations and warned that fourth-quarter results also would be below forecasts. Excluding a charge related to a lawsuit settlement, the company earned $347 million, or 42 cents a share, on sales of $1.51 billion. Analysts were expecting earnings of 44 cents a share and sales of $1.56 billion. A year earlier, the company earned, before items, $404 million, or 47 cents a share, on sales of $1.48 billion.

Boston Scientific expects fourth-quarter earnings of 40 cents to 44 cents a share, below analysts' estimate of 47 cents a share. The company targets sales of $1.55 billion to $1.59 billion, also shy of Wall Street's projection of $1.64 billion. Shares recently traded down 34 cents to $23.96.

Celgene ( CELG) rose 9% after Merrill Lynch upgraded the company's shares to buy from neutral, saying the biotechnology company's Revlimid and Thalomid drugs have the potential to be blockbusters. The stock's recent pullback also provides an attractive entry point, the firm noted. Shares recently rose $4.11 to $51.72.

Shares of Microtek Medical Holdings ( MTMD) fell 4% after the company said that third-quarter sales would be below year-earlier results. Microtek, a maker of safety products for the health-care industry, said it expects sales of $33.5 million, compared with a year-earlier top line of $34 million. The lone analyst forecast called for sales of $34 million. Shares were trading down 15 cents to $3.44.

Other health care volume movers included Pfizer ( PFE), up 5 cents to $24.55; BioCryst Pharmaceuticals ( BCRX), up $1.46 to $15.83; Johnson & Johnson ( JNJ), down 46 cents to $63.56; Amgen ( AMGN), up 33 cents to $76.15; Novavax ( NVAX), up 14 cents to $2.51; Merck ( MRK), up 23 cents to $27.04; Medtronic ( MDT), up 8 cents to $56.03; Schering-Plough ( SGP), up 34 cents to $21.48; and Bristol-Myers Squibb ( BMY), down 9 cents to $22.36.

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