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* S&P 500, Nasdaq on six-day winning streak
* Netflix up after results; Facebook gains on upgrade
* Allergan soars as Ackman and Valeant bid for company
* Dow up 0.4 pct; S&P 500 up 0.4 pct; Nasdaq up 1 pct (Adds Gilead earnings, updates volume)
By Chuck Mikolajczak
NEW YORK, April 22 (Reuters) - U.S. stocks rose on Tuesdayas a host of solid earnings reports, along with strength in thehealthcare sector, helped lift the S&P 500 and Nasdaq to theirsixth straight advance.
Netflix Inc surged 7 percent to $372.90 a day afterreporting strong subscriber growth, a sign the trading favoritestill had room to grow despite recent valuation concerns. Withthe day's gain, the stock moved to the plus side for the yearafter a 21 percent drop in March.
The S&P healthcare index, up 1 percent, was thebest performer of the 10 major S&P sectors. Allergan Inc jumped 15.2 percent to $163.65 a day after activist investorWilliam Ackman teamed up with Canadian drugmaker ValeantPharmaceuticals International Inc to bid for thecompany. U.S.-listed Valeant shares gained 7.5 percent to$135.41.
A deal between Novartis and GlaxoSmithKline, in which the two traded over $20 billion worth ofassets in an effort to cope with healthcare spending cuts andgeneric competition, also bolstered the healthcare sector.U.S.-listed shares of Novartis gained 1.3 percent to$86.56, while Glaxo rose 4.1 percent to $55.30.
Better-than-expected earnings have lifted stocks recently,though companies have largely been exceeding reduced forecasts.Profits are seen rising 1.1 percent this quarter, down from the6.5 percent growth rate estimated at the start of the year.
"What was baked into the market, in spite of a market nearan all-time high, was a sloppy earnings season," said MikeSerio, regional chief investment officer of Wells Fargo PrivateBank in Denver.
"We've had some really good beats at this point, we've had acouple of good announcements today, you throw on the M&Aactivity in the drug sector, at least in the short term,everybody looks pretty excited about this market."
Dow components Travelers Cos Inc and UnitedTechnologies Corp both beat expectations, and UnitedTech raised the low end of its full-year profit outlook. Sharesof Travelers rose 0.6 percent to $86.89 while United Tech added0.8 percent to end at $119.19.
McDonald's Corp reported earnings that fellalongside a drop in U.S. same-store sales, and its stock slipped0.4 percent to $99.32.
With 20 percent of the S&P 500 having reported resultsthrough Tuesday morning, 63 percent have topped earningsexpectations, according to Thomson Reuters data, matching thelong-term average. On the revenue side, 51 percent have exceededforecasts, below the 61 percent long-term average.
The Dow Jones industrial average rose 65.12 points or0.40 percent, to end at 16,514.37. The S&P 500 gained7.66 points or 0.41 percent, to 1,879.55. The Nasdaq Composite added 39.912 points or 0.97 percent, to 4,161.458.
After the close, Gilead Sciences Inc advanced 1.1percent to $73.65 after the drugmaker said its new $1,000hepatitis C pill generated quarterly sales of $2.27 billion,helping the company's quarterly net profit nearly triple.
In another positive sign for equities, the Dow JonesTransportation Average, up 0.6 percent, closed at itsfirst record high since April 2. The index got a boost fromairlines such as United Continental Holdings, up 4.6percent, and Alaska Air Group Inc, up 1.3 percent, whichrose on a 2 percent drop in oil prices.
Facebook Inc shares rose 2.9 percent to $63.03,helping to lift the Nasdaq 100 and the S&P 500. CreditSuisse upgraded the social networking company's stock to"outperform" on higher expectations for its long-term averagerevenue per user.
Volume was light, with about 5.88 billion shares traded onU.S. exchanges, below the 6.7 billion average so far this month,according to data from BATS Global Markets.
Advancing stocks outnumbered declining ones on the NYSE by2,227 to 811, while on the Nasdaq, advancers beat decliners1,900 to 727. (Reporting by Chuck Mikolajczak; Editing by Nick Zieminski andJan Paschal)
