4 MIN. DE LECTURA
* Initial jobless claims fall for fourth straight week
* Biotech shares rebound after sharp two-day decline; energy falls
* Equity markets close at 1 p.m. in holiday-shortened session
* Indexes up: Dow 0.3 percent, S&P 0.2 pct, Nasdaq 0.4 pct (Updates to midday trading)
By Ryan Vlastelica
NEW YORK, Dec 24 (Reuters) - U.S. stocks edged higher on Wednesday, with the Dow and S&P 500 at records and on track for a sixth straight daily advance as biotech stocks rallied and data pointed to improving economic conditions.
The day's action was light, with many market participants already out for the Christmas holiday. The stock market will close three hours early on Wednesday and will be closed all of Thursday.
Equities have been on a hot streak of late, with the Dow closing above 18,000 for the first time ever on Tuesday. The S&P 500 is up 5.7 percent over the past six sessions and is on track for its 52nd record close of this year, the most since 1995 and the fourth best in history.
Those gains have come on central bank assurances and improving economic data, a trend that continued with jobless claims on Wednesday. Initial claims for state unemployment benefits dropped 9,000 to a seasonally adjusted 280,000, their fourth straight week of declines, and below the forecast of 290,000.
"Equities are heading towards the year-end finale in a good position," said Terry Sandven, senior equity strategist at U.S. Bank Wealth Management in Minneapolis. "Fundamental and macro factors are supportive of higher equity prices, and clearly today if you look at the claims data which was generally in line with expectations, it still points toward an improving labor market."
The day's gains were broad, with seven of the 10 primary S&P 500 sectors rising on the day. The Nasdaq Biotech index was a particular standout, up 2.3 percent in a partial rebound from the drop of nearly 7 percent over the previous two sessions.
Biotechs made up the S&P's top six percentage gainers. Celgene Corp rose 4 percent to $110.39 while Gilead Sciences added 3.1 percent to $92.23.
Adamas Pharmaceuticals Inc jumped 22.6 percent to $17.96 after the U.S. Food and Drug Administration approved a drug developed with Actavis Plc to treat dementia in Alzheimer's patients. Actavis shares rose 0.3 percent to $256.67.
At 11:00 a.m. (1600 GMT) the Dow Jones industrial average rose 51.5 points, or 0.29 percent, to 18,075.67, the S&P 500 gained 3.85 points, or 0.18 percent, to 2,086.02 and the Nasdaq Composite added 19.27 points, or 0.4 percent, to 4,784.70.
Both the Dow and S&P are on track for their sixth straight daily advance, the longest streak for the benchmark S&P since June.
Energy shares continued their recent weakness as crude oil lost 3.1 percent to $55.38 per barrel and hovered near its lowest level since 2009. The S&P energy index fell 1.4 percent; Exxon Mobil lost 1.4 percent to $93.30 while Chevron slid 1 percent to $112.82.
Advancing issues outnumbered declining ones on the NYSE by 1,579 to 1,309, for a 1.21-to-1 ratio on the upside; on the Nasdaq, 1,554 issues rose and 979 fell for a 1.59-to-1 ratio favoring advancers.
The benchmark S&P 500 index was posting 74 new 52-week highs and 5 new lows; the Nasdaq Composite was recording 72 new highs and 17 new lows. (Editing by Meredith Mazzilli)