Updated from 2:00 p.m. EDT

Shares of

OSI Pharmaceuticals

( OSIP) were among the best-performing health and pharmaceutical stocks Friday, rising 45.2% after

AstraZeneca

(AZN) - Get Report

said that Iressa, AstraZeneca's lung cancer drug, failed to show a significant survival benefit in patients who were part of a major clinical trial.

Word of the disappointing results sent shares of OSI soaring. OSI's Tarceva, a rival drug that is used to treat non-small cell lung cancer, gained Food and Drug Administration approval in November. The disappointing AstraZeneca trial results now give OSI and its partner

Genentech

( DNA) a competitive advantage in the lung cancer market. Shares of OSI traded up $21.28 to $68.38; Genentech traded up $2.87 to $51.36; and AstraZeneca traded down $3.11 to $37.10.

Shares of

WellCare Health Plans

(WCG) - Get Report

fell 3.7% after the company said it would sell 1.5 million shares of stock at $32 apiece in a follow-on offering, for proceeds of about $48 million. An additional 6 million shares are being sold by selling shareholders. The selling price represents about a 3% discount to Thursday's closing price of $33.12. WellCare will use the proceeds to fund general corporate purposes, which may include acquisitions. Shares traded down $1.22 to $31.90.

Other health care volume movers included

Pfizer

(PFE) - Get Report

, down $3.18 to $25.80;

Merck

(MRK) - Get Report

, down 20 cents to $31.59;

Eli Lilly

(LLY) - Get Report

, down $1.38 to $56.02;

Schering-Plough

( SGP), down 31 cents to $20.15; and

Bristol-Myers Squibb

(BMY) - Get Report

, down 34 cents to $25.22.