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Spirit Aero up following report of Boeing ( BA ) nearing buyout

deal

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Sarepta surges on expanded use of gene therapy

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Gilead gains after long-acting HIV drug trial success

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S&P 500 crossed 5,500 points on Thursday

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Futures down: Dow 0.12%, S&P 500 0.08%, Nasdaq 0.01%

(Updated at 8:45 a.m. ET/1245 GMT)

By Lisa Pauline Mattackal and Ankika Biswas

June 21 (Reuters) - Wall Street was set for a muted open

on Friday as chip stocks lost ground, with focus on data from

the manufacturing and services sectors 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 ( NVDA ) dropped 1.7% in premarket

trading on Friday, after losses in the previous session saw its

market valuation fall back below that of Microsoft ( MSFT ).

Semiconductor stocks Qualcomm ( QCOM ), Micron Technology ( MU )

and Arm Holdings were down between 0.8% and 3.4%,

while megacaps such as Microsoft ( MSFT ) and Apple ( AAPL ) rose 0.1%

and 0.3%, respectively.

Wall Street's bumper gains since the final leg of 2023 have

been primarily driven by the likes of Nvidia ( NVDA ) 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.

"The largest companies in the S&P 500 are excellent, very

profitable and growing quickly ... but they are getting a little

bit expensive," said Chris Zaccarelli, chief investment officer

at Independent Advisor Alliance.

"We wouldn't be surprised if the market takes a breather and

cools off a bit in the short term."

Investors are also assessing a string of weakening economic

data and commentary from 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. Existing housing

sales data is on tap as well.

Friday's session will also mark the expiry of quarterly

derivatives contracts tied to stocks, index options and futures,

also known as "triple witching".

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 8:45 a.m. ET, Dow e-minis were down 47 points,

or 0.12%, S&P 500 e-minis were down 4.5 points, or

0.08%, and Nasdaq 100 e-minis were down 1.75 points, or

0.01%.

Spirit AeroSystems ( SPR ) jumped 4.5% following a Reuters

report that Boeing ( BA ) is nearing a deal to buy back the

airplane parts supplier after months of talks.

Drugmaker Gilead jumped 3.0%, 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 ( SRPT ) soared 33.2% 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.