Shares of

Alexion Pharmaceuticals

(ALXN) - Get Report

were among the best-performing health-related stocks Thursday, climbing 23% after the company reported positive results from its Phase III trial of eculizumab, a drug used to treat paroxysmal nocturnal hemoglobinuria, a rare form of hemolytic anemia.

The company said that all of its primary and secondary endpoints in the international trial were met with statistical significance. "The compelling results observed with eculizumab in the PNH Triumph efficacy study represent an important accomplishment in the evolution of Alexion toward a commercial entity," the company said. The company is planning to submit marketing applications for eculizumab during the second half of 2006. Shares were trading up $4.94 to $26.89.

CNS

(CNXS)

slumped 19% after the maker of Breathe Right strips posted lower-than-expected third-quarter results and narrowed its full-year sales guidance. The company earned $4 million, or 26 cents a share, on sales of $30.9 million. Analysts surveyed by Thomson First Call expected earnings of 28 cents a share and sales of $31.1 million. During the year-earlier period, the company earned $4.4 million, or 30 cents a share, on sales of $28.7 million.

Looking ahead, CNS continues to expect fiscal 2006 earnings of $1.05 to $1.12 a share. Sales, meanwhile, are now expected to be $109 million to $112 million. Previously, the company projected sales of $109 million to $113 million. Shares were trading down $4.72 to $20.84.

Shares of

Varian Medical Systems

(VAR) - Get Report

rose 6% after the company posted first-quarter results that topped Wall Street forecasts. The company earned $41.2 million, or 30 cents a share, on sales of $334 million. Excluding stock-based compensations costs, the company earned 34 cents a share for the quarter ended Dec. 30. Analysts expected earnings of 33 cents a share, before items, and sales of $330.9 million. During the year-earlier period, the company earned $40.3 million, or 29 cents a share, on sales of $299 million.

Looking ahead, Varian expects second-quarter and fiscal-year earnings, excluding stock-based compensation costs, to grow by 17% to 18% over fiscal 2005. Sales for the year are projected to rise by 14%, with second-quarter sales expected to be up in the midteens percentage. Analysts are projecting second-quarter earnings of 46 cents a share on sales of $401.2 million.

Separately, Varian announced a contract to equip England's Oxford Churchill Hospital with six Clinac linear accelerators and provide information management and treatment planning. The initial order, worth $13 million, was booked during the first quarter. Shares were up $3.13 to $58.01.

Amgen

(AMGN) - Get Report

fell 5% after the biotech company posted fourth-quarter earnings that were a penny shy of expectations. Amgen earned $824 million, or 66 cents a share, on sales of $3.27 billion. Excluding items, the company earned $928 million, or 75 cents a share. Analysts expected earnings of 76 cents a share and sales of $3.33 billion. During the year-earlier quarter, the company posted adjusted earnings of $749 million, or 58 cents a share, on sales of $2.8 billion.

For 2006, Amgen sees earnings of $3.55 to $3.70 a share on sales of $13.9 billion to $14.4 billion. The guidance doesn't include the impact of stock option compensation expense or acquisition-related expenses. Amgen expects stock option expenses of 12 cents to 14 cents a share during 2006. Analysts are projecting 2006 earnings of $3.65 a share and sales of $14.4 billion. Shares were down $3.60 to $71.87.

Shares of

Eli Lilly

(LLY) - Get Report

traded actively after the company's fourth-quarter earnings were better than expected, but sales were slightly below estimates. The drugmaker earned $700.6 million, or 64 cents a share, on sales of $3.88 billion. Excluding items, the company earned $871.6 million, or 80 cents a share. Analysts expected adjusted earnings of 78 cents a share on sales of $3.9 billion. During the year-ago quarter, the company posted adjusted earnings, which excludes items, of $814.3 million, or 75 cents a share, on sales of $3.64 billion.

Looking ahead, Lilly sees first-quarter earnings of 73 cents to 75 cents a share, in line with analysts' forecasts of 75 cents a share. For all of 2006, the company projects earnings of $3.10 to $3.20 a share, bracketing the $3.13 a share that analysts are projecting. Shares were trading down 10 cents to $57.07.

Other health care volume movers included

Bristol-Myers Squibb

(BMY) - Get Report

, up 62 cents to $22.59;

Pfizer

(PFE) - Get Report

, up 7 cents to $24.90;

Johnson & Johnson

(JNJ) - Get Report

, up 21 cents to $58.71;

Merck

(MRK) - Get Report

, up 69 cents to $33.88;

Boston Scientific

(BSX) - Get Report

, down 32 cents to $23.22;

Schering-Plough

( SGP), down 1 cent to $19.60; and

Elan

(ELN)

, up 31 cents to $14.18.