By Victor Reklaitis, MarketWatch

Twitter dives in premarket action, while Gilead jumps

U.S. stock futures notched up early Wednesday, putting Wall Street on track to build on Tuesday's gains, though big moves are unlikely while investors wait for a Federal Reserve statement due later.

S&P 500 futures rose 1.30 points, or 0.1%, to 2,088, while those for the Dow Jones Industrial Average tacked on 16 points, or 0.1%, to 17,562. Nasdaq 100 futures added 2.25 points, or 0.1%, to 4,558.25.

On Tuesday, the U.S. stock market climbed and halted a five-session losing streak (http://www.marketwatch.com/story/us-stock-futures-climb-with-key-fed-meeting-in-focus-2015-07-28), as the Dow gained nearly 190 points and fears about recent China's stock selloff abated somewhat. The S&P 500 jumped 1.2% for its biggest rise in more than two months.

Fed announcement: The U.S. central bank is wrapping up a two-day meeting and will release a brief statement at 2 p.m. Eastern Time. No news conference has been scheduled.

While the Fed is unlikely to tip its hand about whether it will raise interest rates at its September meeting, investors nonetheless will read its latest policy statement closely.

"A July rate hike looks unlikely, but a September liftoff appears to be well on the way to being priced into currency markets, so any hints that come out of the statement could have a significant impact on trading," said Colin Cieszynski, chief market strategist at CMC Markets, in a note late Tuesday.

See: Fed seen staying mum (http://www.marketwatch.com/story/fed-seen-staying-mum-but-second-quarter-gdp-report-pencils-out-as-game-changer-2015-07-26)

Other markets: Chinese stocks mostly closed higher Wednesday, with the Shanghai Composite up more than 3% (http://www.marketwatch.com/story/china-stocks-remain-weak-as-investors-focus-on-the-fed-2015-07-29), recovering partly from Monday's 8.5% slide that helped spark a global selloff. European equities on Wednesday mostly gained ground.

Crude-oil prices dropped, while gold and the dollar (http://www.marketwatch.com/story/dollar-holds-steady-against-yen-euro-ahead-of-fomc-2015-07-29) were little changed.

Movers & Shakers: Gilead Sciences Inc. (GILD) was the biggest gainer among S&P 500 stocks in premarket action, rising about 4% after the biotech late Tuesday posted quarterly profit and revenue that beat forecasts (http://www.marketwatch.com/story/gilead-rallies-after-earnings-beat-wall-streets-expectations-2015-07-28).

Twitter Inc. (TWTR) was down nearly 12% premarket after its earnings report late Tuesday, with investors focusing on the social-media company's disappointing user growth (http://www.marketwatch.com/story/twitter-revenue-jumps-user-growth-disappoints-2015-07-28).

Before the open, Humana Inc. (HUM), MasterCard Inc. (MA) and Altria Group Inc. (MO) are among the companies slated to deliver quarterly results. Whole Foods Market Inc. (WFM) and Facebook Inc. (FB) results are due after the closing bell.

Read more: MasterCard, Facebook, Humana earnings in focus (http://www.marketwatch.com/story/mastercard-facebook-humana-earnings-in-focus-2015-07-28)

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