Shares of

Pharmacopeia

were among the best-performing health-related stocks Thursday, surging 19% after the company announced a drug-discovery and development alliance with

GlaxoSmithKline

(GSK) - Get Report

.

Under the terms of the agreement, which calls for the development and commercialization of novel drugs in a broad array of areas, Pharmacopeia will receive a $15 million cash payment from GlaxoSmithKline. Additionally, the company will be eligible to receive milestone payments of up to $83 million. Pharmacopeia also will be able to receive double-digit royalty payments, which are tied to product sales. At the beginning of the alliance, GlaxoSmithKline will receive warrants to buy Pharmacopeia stock at a 25% premium to Pharmacopeia's trailing 30-day closing price average. Shares of Pharmacopeia were recently trading up 91 cents to $5.73.

Arrow International

shares fell 7% after the medical-device company's second-quarter results and third-quarter earnings projection missed Wall Street's expectation. For the quarter ended Feb. 28, the company earned $12.6 million, or 28 cents a share, on revenue of $116.5 million. Analysts polled by Thomson First Call expected earnings of 29 cents a share and revenue of $117.5 million. During the year-earlier quarter the company earned $5.3 million, or 12 cents a share, on revenue of $109.2 million.

For the third quarter, Arrow predicts earnings of 33 cents to 35 cents a share, with revenue of $122 million to $126 million. Analysts, on average, project earnings of 36 cents a share and revenue of $123 million. Arrow shares were down $2.25 to $30.85.

Shares of

ViroPharma

(VPHM)

rose 9% after the company announced positive phase-II results from its clinical study of maribavir, an oral antiviral drug candidate for bone marrow-transplant patients. The drug is being tested to inhibit the reactivation of a type of infection, cytomegalovirus, in the patients. "We could not have hoped for better results, as these data show that treatment with maribavir dramatically reduces the incidence of CMV reactivation in these very sick patients," the company said. "The only cases of CMV disease in this trial occurred in the placebo group -- there were no cases of CMV disease in subjects who received maribavir," ViroPharma said. The company will now move ahead with plans for a phase-III trial. Shares were trading up $1.06 to $12.75.

Schiff Nutrition

, formerly known as

Weider Nutrition

, soared 18% after the maker of vitamins and supplements posted big gains in third-quarter earnings. For the quarter ended Feb. 28, the company earned $3.2 million, or 12 cents a share, up from $1.2 million, or 5 cents a share, a year earlier. Sales rose to $49.6 million from $45.2 million. The company said results were helped by a 29% jump in sales of branded products and improved gross margins. Schiff shares were trading up 89 cents to $5.97.

Shares of

Carrington Laboratories

fell 7% after the biopharmaceutical company said it swung to a fourth-quarter loss. The company reported a loss of $3.8 million, or 35 cents a share, on revenue of $5.8 million. Excluding expenses related to its DelSite Biotechnologies subsidiary, the company recorded a loss of $2.9 million, or 27 cents a share. During the year-earlier quarter, the company posted a pro forma profit, excluding DelSite expenses, of $708,000, or 7 cents a share, on revenue of $7.8 million. Shares were trading down 40 cents to $5.56.

Other health care volume movers included

Pfizer

(PFE) - Get Report

, up 10 cents to $25.34;

Generex Biotechnology

(GNBT)

, down 8 cents to $3.20;

UnitedHealth Group

(UNH) - Get Report

, up 30 cents to $56.25;

Boston Scientific

(BSX) - Get Report

, up 9 cents to $23.34;

Johnson & Johnson

(JNJ) - Get Report

, down 14 cents to $59.37;

Amgen

(AMGN) - Get Report

, up 72 cents to $72.74;

Encysive Pharmaceuticals

, up 2 cents to $4.96;

Bristol-Myers Squibb

(BMY) - Get Report

, down 8 cents to $24.86;

Elan

(ELN)

, up 16 cents to $14.75;

Merck

, down 37 cents to $35.43; and

Schering-Plough

(SGP)

, up 4 cents to $19.26.