U.S. stock index futures were little changed on Friday as megacap tech and chip stocks lost ground, with investors awaiting manufacturing and services sectors surveys for more clues on the health of the world's largest economy.

The S&P 500 crossed the 5,500 point milestone during Thursday's session, however, both the benchmark index and the tech-heavy Nasdaq closed lower as megacap stocks pulled back.

AI chip firm Nvidia dropped 1.4% in premarket trading on Friday, after losses in the previous session saw its market valuation fall back below that of Microsoft.

Semiconductor stocks Qualcomm, Micron Technology and Arm Holdings were down between 1% and 2%, while megacaps such as Microsoft and Meta Platforms were down around 0.3% each.

Wall Street's bumper gains since the final leg of 2023 has been primarily driven by the likes of Nvidia and a handful of other heavily weighted stocks linked to artificial intelligence. Analysts, however, have flagged whether the strong increase in their valuations is sustainable.

Investors are also assessing a string of weakening economic data and commentary from the U.S. Federal Reserve officials that interest rates could remain higher for longer if there is no consistent improvement in inflation numbers.

Later in the day, focus will be on flash S&P PMI readings, that are expected to fall slightly, but remain above the 50 level that shows activity is still expanding.

"Any unexpected slowdown in the U.S. economy could spark some jitters ... but investors will be hoping to see a moderation in price pressures, which would be positive for risk sentiment," said Raffi Boyadjian, lead investment analyst at forex broker XM.

Friday's session will also mark the expiry of quarterly derivatives contracts tied to stocks, index options and futures, also known as "triple witching".

"With Wall Street hit by profit taking after almost uninterrupted gains during June, there is a risk of some further volatility on Friday because of triple witching," Boyadjian said.

All three major Wall Street stock indexes are set to close the week higher, as is the small-cap focused Russell 2000 .

Money markets are pricing in a 58% chance of a 25-basis point interest rate cut at the Fed's meeting in September, and still expect about two rate cuts this year, according to LSEG's FedWatch data.

At 7:29 a.m. ET, Dow e-minis were up 7 points, or 0.02%, S&P 500 e-minis were down 1.75 points, or 0.03%, and Nasdaq 100 e-minis were up 2.25 points, or 0.01%.

Spirit AeroSystems jumped 4.2% following a Reuters report that Boeing is nearing a deal to buy back the airplane parts supplier after months of talks.

Drugmaker Gilead jumped 2.9%, extending gains from Thursday as a late-stage study showed its long-acting injectable drug was more effective in preventing HIV infection in women compared to its existing daily pill Truvada.

Sarepta Therapeutics soared 37.1% after the U.S. Food and Drug Administration allowed the expanded use of the company's gene therapy for patients with Duchenne muscular dystrophy aged four and older.

(Reporting by Lisa Mattackal and Ankika Biswas in Bengaluru; Editing by Shounak Dasgupta)