Icon's

(ICLR) - Get Report

shares rose after the company announced a 2-for-1 stock split, subject to shareholder approval. The Dublin, Ireland-based provider of outsourced drug and device development will hold a general meeting of shareholders next month. Shares of Icon gained 1.1% to $69.48.

Vaccine developer

Iomai

( IOMI) spiked 23% following an upgrade on the stock to buy from neutral. According to UBS analyst Annabel Samimy, the company is developing dosing strategies for pandemic flu treatments and a possible partnership to develop a needle-free flu vaccine that could boost the stock to $5. Shares were trading up 28.2% to $4.45.

Allscripts Healthcare Solutions

(MDRX) - Get Report

sank following a downgrade of the stock by UBS analyst Donald Hooker to reduce from neutral. UBS maintained its price target of $18. Shares were down 6% to $20.22. Separately, Allscripts said California's Riverside Physician Network has decided to use the company's TouchWorks Electronic Health Record technology to connect its network of 200 doctors.

Cancer drugmaker

Celgene

saw its shares move lower after investment firm Goldman Sachs initiated coverage of the stock with a neutral rating and a $50 price target. While the company has strong sales momentum and improving margins, according to biotech analyst May-Kin Ho, Celgene faces reimbursement pressures as off-label use of its drugs are under increasing scrutiny. The company's blood cancer drugs Revlimid and Thalomid also face competitive pressure from

Millennium Pharmaceuticals'

( MLNM) Velcade. Shares fell 2.6% to $43.46.

Idenix Pharmaceuticals

(IDIX)

shares sank 6.7% to $8.81 on a downgrade by investment firm Goldman Sachs. While May-Kin Ho deems the hepatitis B drugmaker's research pipeline "above average," she says the hepatitis B market is limited and the company has plenty of competition from companies like

Gilead

(GILD) - Get Report

and

Bristol-Myers Squibb

(BMY) - Get Report

. Ho downgraded the stock to neutral from buy and set a 12-month price target of $11.

Adams Respiratory Therapeutics'

( ARXT) shares fell 7.2% to $41.84 after the company said an unnamed competitor submitted an application to the Food and Drug Administration to sell a drug that could be pitted against its over-the-counter expectorant Mucinex. Also on Friday, Adams filed a registration statement covering more than 10 million shares held by institutional investors as part of a contractual obligation.

Other health stocks falling were

Affymetrix

(AFFX)

, whose shares sank 4% to $21.24; generic drugmaker

Teva Pharmaceutical

(TEVA) - Get Report

, down 1.3% to $34.17; nervous-system drug developer

Vanda Pharmaceuticals

(VNDA) - Get Report

, 5.7% lower to $9.27;

IDM Pharma

( IDMI), whose shares fell 6.7% to $2.33; and

Cyclacel Pharmaceuticals

(CYCC) - Get Report

, down 4.6% to $5.16.

Moving higher were medical-device maker

Medtronic

(MDT) - Get Report

, up 2.2% to $45.49;

Allied Healthcare International

( AHCI), up 12% to $1.68;

Dynacq Healthcare

(DYII)

, up 8.7% to $2;

SGX Pharmaceuticals

( SGXP), up 5% to $4.95; and

Natural Health Trends

( BHIP) up 6.3% to $2.55.