Thursday's Health Winners & Losers - TheStreet

Luminex Corp.

(LMNX) - Get Report

was one of Thursday's biggest gainers after swinging to a fourth-quarter profit, boosting shares by 30.6%. Luminex was adding $3.89 to $16.62.

Shares of

XenoPort

(XNPT)

were up 12.9% after announcing an agreement with drugmaker

GlaxoSmithKline

(GSK) - Get Report

to co-develop a new treatment for restless leg syndrome and neuropathic pain. XenoPort was rising $3.26 to $28.50.

Alkermes

(ALKS) - Get Report

jumped 12.3% after the company raised its fiscal-year guidance thanks to a solid third quarter. Alkermes was gaining $1.84 to $16.84.

Affymetrix

(AFFX)

was rising 6.2% after posting a better-than-expected fourth-quarter profit, despite falling 72% from a year ago. Affymetrix, which manufactures chips used in genetic research and drug development, was up $1.64 to $28.31.

Myriad Genetics

(MYGN) - Get Report

said late Wednesday it will sell 3 million shares under an existing shelf registration. It will grant the underwriter a 30-day option to buy an additional 450,000 shares. Myriad was losing $1.22, or 3.3%, to $35.89.

Elsewhere,

Arena Pharmaceuticals

(ARNA) - Get Report

was jumping 6% to $14.24,

ImClone Systems

(IMCL)

was adding 3.6% to $30.50, and

Nektar Therapeutics

(NKTR) - Get Report

was gaining 2.8% at $12.64.

Merck

(MRK) - Get Report

was off 0.6% to $43.99, and

Schering-Plough

( SGP) eased 0.6% to $24.53.