Stock index futures edged lower on Thursday as investors awaited weekly jobless claims data for signs the economy will continue to support equities as they come off their best first quarter in 14 years.

Improvement in the data has stalled in recent weeks and could be a worrying sign for investors. The Labor Dept releases first-time claims for jobless benefits at 8:30 a.m. EDT (1230 GMT). Economists in a Reuters survey forecast 350,000 new filings, compared with 348,000 in the prior week.

The economic numbers have been softening a little bit here in the U.S., but I also think people are looking to Asia and the weakness there, which is getting pretty profound, said Rick Fier, director of trading at Conifer Securities in New York.

S&P 500 futures fell 3.7 points but were just above fair value, a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract. Dow Jones industrial average futures lost 32 points, and Nasdaq 100 futures were off 5.75 points.

The S&P 500 is up 11.8 percent this quarter, its best start to the year since 1998 and its best quarter since the third period of 2009.

Some investors are looking for a pullback early in the second quarter after the strong first quarter and seeking confirmation the economy is not about to slow.

What we are really keying on now is what happens in the first week in April, said Fier. Everybody remembers last year at this time and 'sell in May and go away' was a big trade that worked, he said, referring to the old stock market adage.

The Commerce Dept releases its final estimate for fourth-quarter gross domestic product (GDP) and corporate profits, also at 8:30 a.m. Economists forecast a 3.0 percent annualized pace of GDP growth, a repeat of the preliminary estimate.

European stocks dipped 0.8 percent early Thursday, hitting three-week lows as lower-than-expected U.S. macro data fueled fears of a slowdown in global growth. The Nikkei eased 0.7 percent. The index is poised for its best first-quarter performance in 24 years. <.EU>

Roche Holding AG hiked its cash bid for U.S. gene sequencing company Illumina Inc to $6.7 billion, the Swiss drugmaker said as it sought to win over shareholders before Illuminant's annual meeting next month. Illumina rose 2.6 percent to $51.10.

Fossil Inc will replace Medco Health Solutions Inc in the S&P 500 as Express Scripts Inc acquires Medco in a deal expected to be completed soon. The date of the index change has yet to be announced.

Also on the mergers front, Pentair Inc

reached a $4.6 billion stock deal to absorb Tyco International Ltd's flow-control business, roughly doubling Pent air's size. The stock fell 0.4 percent to $46.12.

Private equity-backed Redford Corp , an industrial parts maker, priced its initial public offering at $18 a share on Wednesday, at the low end of its expected range, an underwriter said.

Applied Materials Inc forecast 2012 results below Wall Street targets and will cut costs to offset a persistent downturn in solar and display markets. The company is the latest to generate caution ahead of first-quarter earnings season in April.

Electronics retailer Best Buy Co Inc is due to report quarterly results, with earnings per share seen at $2.16 versus $1.98 one year earlier, according to a Reuters poll.

(Reporting By Edward Krudy; editing by Jeffrey Benkoe)