* ECB cuts interest rates
* U.S. GDP tops expectations
* Twitter shares to debut on NYSE
* Qualcomm falls after results, outlook
* Indexes down: Dow 0.06 pct, S&P 0.35 pct, Nasdaq 0.99 pct
U.S. stocks fell on Thursday, as a drop in Qulacomm overshadowed earlier enthusiasm in the wake of an interest rate cut by the European Central Bank.
Qualcomm Inc shares dropped 3.2 percent to $67.52 as the biggest drag on both the S&P 500 and Nasdaq 100 indexes after the company reported quarterly earnings and forecast revenue below expectations.
Stock futures had jumped higher earlier in the day after the European Central Bank cut interest rates to a record low, responding to a slump in inflation that sparked fears the euro zone's economic recovery could stall.
The move by the ECB reinforced expectations global central banks will continue to take actions to buoy struggling economies worldwide
"The ECB has indicated they were tied to interest rates already in prior meetings, focusing on price stability, and as price stability deteriorated that warranted an interest rate cut," said Anastasia Amoroso, Global Market Strategist at J.P. Morgan Funds in New York.
"There was a clear indicator that pushed them to make the decision, which is the deterioration in core inflation, and in a way they had no choice but to show to the market their credibility by providing support to the economy."
Investors will also brace for the market debut of Twitter Inc. It priced its initial public offering above the expected range at $26 per share to raise at least $1.8 billion, a sign of strong investor demand for the most highly anticipated U.S. public float since Facebook Inc. Shares were last indicated to open between $45 and $46 per share.
"I've been concerned about revenues and the fact that one of the risks the company has pointed out that it may never make money," said Kim Forrest, senior equity research analyst, Fort Pitt Capital Group in Pittsburgh.
"This is not the kind of company, even if I hail from technology, that I am prepared to invest in or that I suggest anybody else ever invest in."
The Dow Jones industrial average fell 9.63 points or 0.06 percent, to 15,737.25, the S&P 500 lost 6.27 points or 0.35 percent, to 1,764.22 and the Nasdaq Composite dropped 39.061 points or 0.99 percent, to 3,892.885.
Economic data showed gross domestic product expanded at a 2.8 percent annual rate, the quickest pace since the third quarter of 2012, an acceleration from a 2.5 percent clip in the second quarter and above economists' expectations for a 2.0 percent rate.
Separately, weekly initial jobless claims fell 9,000 to a seasonally adjusted 336,000 last week, roughly in line with expectations of a drop to 335,000.
The GDP data, coupled with Friday's payrolls report, may give investors insight into how long the Fed may keep intact its $85 billion a month in bond purchases. The central bank's stimulus measures have been a key component of the 24.1 percent year-to-date gain in the S&P 500, putting the index on pace for its best yearly performance since 2003.
S&P 500 companies scheduled to report earnings after the close on Thursday include Dow component Walt Disney Co, Nvidia Corp and Priceline.com Inc.