NEW YORK (AFP) - Wall Street pulled back from the celebration that followed good news on a potential Covid-19 vaccine, ending Tuesday's (Nov 10) session mixed.

The benchmark Dow Jones Industrial Average finished the day with a 0.9 per cent gain at 29,420.92, while the broader S&P 500 dipped 0.1 per cent to 3,545.53.

But the tech-heavy Nasdaq lost 1.4 per cent to close at 11,553.86.

Optimism about Monday's announcement from Pfizer and BioNTech that their vaccine was 90 percent effective was tempered by the realisation the economic gains likely will not be felt until late next year since it will take months for any vaccine to be widely distributed.

Meanwhile, investors are shifting away from the stay-at-home stocks, like videoconference service Zoom, and are returning to back-to-normal shares like airlines and cruise companies.

Quincy Krosby from Prudential Financial said "tech names were overbought, reaching the point where we would expect to see some consolidation."

That trend should continue as focus turns to "sectors that will benefit from a vaccine once it is distributed and take us to the other side of the pandemic," Krosby said.

Uncertainty generated by the US election has receded after Joe Biden defeated President Donald Trump, and Trump's avalanche of legal challenges against the result have not made waves in markets.

Investors continue to bet that Biden will deliver a new stimulus package to boost the US economy, although the chance Republicans will retain control of the Senate mean the package may not be as expansive as they would like.

Pfizer shares gained for most of the day but dipped late in the session, ending 1.3 per cent lower.

Zoom, which millions of people have relied on during the pandemic for business and social activities, lost another 9 per cent after plunging more than 17 per cent on Monday.

But home exercise equipment company Peloton gained 5.2 per cent after announcing a deal with pop superstar Beyonce to develop themed fitness routines based on her music.