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* Cisco gains on quarterly results beat

* CVS hurt by Blue Shield of California's move to cut reliance

* Pfizer up after study on its updated COVID-19 shot

* Initial weekly jobless claims drop more than expected

NEW YORK, Aug 17 (Reuters) - Wall Street's main indexes closed lower after choppy trading on Thursday as losses in healthcare stocks eclipsed gains in Cisco and energy stocks, while upbeat economic data kept alive fears of interest rates remaining higher for longer.

Weighing heavily on the S&P 500, CVS Health tumbled on news that Blue Shield of California plans to cut its reliance on the company as its pharmacy benefit manager (PBM) and work with others including Amazon.com.

Shares of major health insurers UnitedHealth and Cigna, which also have PBM units, dropped, pushing the broader S&P 500 healthcare index lower.

According to preliminary data, the S&P 500 lost 34.59 points, or 0.79%, to end at 4,369.74 points, while the Nasdaq Composite lost 158.66 points, or 1.18%, to 13,315.97. The Dow Jones Industrial Average fell 295.86 points, or 0.85%, to 34,469.88.

Higher oil prices lifted shares of Exxon Mobil and Chevron, as commodities were helped by hopes that China's central bank was seeking to bolster the property market and wider economy.

Pressuring equities further, the yield on 10-year U.S. Treasury notes hit its highest level since October as a raft of strong economic data this week stokes concerns the Fed could keep interest rates at the current level for longer.

"Stocks may be choppy in the near term while we wait for either earnings to pick up or yields to come down," said Jeffrey Buchbinder, chief equity strategist at LPL Financial.

A report from the Labor Department showed a fall in jobless claims last week, signaling the labor market remained tight.

Minutes from the Fed's July meeting released on Wednesday showed most policymakers prioritizing the battle against inflation, adding to uncertainty about the central bank's interest rate path.

The stock market's weakness in recent days is due to robust U.S. economic growth suggesting the Fed is likely going to embrace "high rates for longer," said Barry Bannister, chief equity strategist at Stifel.

A majority of traders expect the Federal Reserve to keep rates unchanged in September, though bets of a pause have slipped to 86.5% from about 89% a week earlier, according to CME Group's Fedwatch tool.

Keeping a lid on losses, Cisco Systems gained after the networking equipment maker's fourth-quarter results beat estimates, and its CEO talked up artificial intelligence opportunities.

Shares of Pfizer rose as the company said its updated COVID-19 shot, which is being tested against emerging variants, showed neutralizing activity against the "Eris" subvariant in a study conducted on mice.

Vaccine makers Moderna and Novavax also

rose

as U.S. data showed COVID-19-related hospitalizations up more than 40% from recent lows hit in June.

Retail heavyweight Walmart raised its full-year forecasts after beating second-quarter sales estimates, but its shares fell.

(Reporting by Amruta Khandekar and Shristi Achar A in Bengaluru Editing by Vinay Dwivedi and Deepa Babington)