Health Stocks in Motion - TheStreet

Updated from 2:45 p.m. EST

Shares of

Elan

(ELN)

were among the worst-performing health-related stocks Thursday, tumbling 53.6% after the company and its partner

Biogen Idec

(BIIB) - Get Report

said that a third patient using their Tysabri multiple sclerosis drug developed a rare and often fatal brain infection.

An ongoing safety evaluation of Tysabri turned up the latest revelation. The companies said that a patient who was enrolled in a phase III trial studying Tysabri for treatment of Crohn's disease died from the disease, which is known by the abbreviation PML. At the time of the patient's death -- in December 2003 -- the companies thought the death resulted from malignant astrocytoma, a form of brain cancer. The patient had received eight doses of Tysabri over an 18-month period, and according to the companies, prior medication history included multiple courses of immunosuppressant agents. Shares of Elan traded down $3.74 to $3.24, while shares of Biogen Idec traded down $3.84, or 10%, to $34.51.

Ligand Pharmaceuticals

( LGNDE) traded actively after the company received a delisting notification from

Nasdaq

market officials. As a result of the company's inability to file its annual report in a timely fashion, Ligand is currently not in compliance with Nasdaq market rules. In response to the delisting notification, Ligand said that it would request a hearing before a Nasdaq panel in an attempt to keep its stock from being delisted. Its stock will remain listed until the Nasdaq renders a final decision on Ligand's request. Shares traded up 22 cents to $5.73 on volume of 2.8 million shares.

Shares of

AmerisourceBergen

(ABC) - Get Report

rose 2.7% after the drug wholesaler said that it would buy almost 5.3 million shares of its own stock at $55.80 a share as part of an accelerated repurchase transaction with Bank of America. The buyback will complete the company's previously authorized 5.7-million-share repurchase plan. Shares traded up $1.49 to $57.29.

Smith & Nephew

(SNN) - Get Report

fell 5.6% after it and three other companies received a subpoena from the U.S. attorney's office in Newark, N.J. The company said that it would turn over documents and information pertaining to consulting, professional service and remuneration agreements -- with regard to reconstructive products -- between its orthopedics division and orthopedic surgeons.

Stryker

(SYK) - Get Report

,

Biomet

( BMET) and DePuy Orthopaedics, a

Johnson & Johnson

(JNJ) - Get Report

unit, received similar subpoenas. Shares of Smith & Nephew traded down $2.77 to $47.02.

Other health care movers included

Pfizer

(PFE) - Get Report

, down 2 cents to $26.27;

Zimmer Holdings

(ZMH)

, down $4.80 to $77.81;

Merck

(MRK) - Get Report

, down 7 cents to $32.37;

Amgen

(AMGN) - Get Report

, down 78 cents to $58.21;

Schering-Plough

( SGP), up 13 cents to $18.15;

Aastrom Biosciences

(ASTM)

, down 9 cents to $2.08;

StemCells

(STEM)

, down 11 cents to $3.15; and

Genentech

( DNA), down 47 cents to $56.61.