5 things to know before the stock market opens Tuesday

Here are the most important news, trends and analysis that investors need to start their trading day

Dow futures drop sharply as omicron fears resurfaceFed’s Powell to tell Senate new variant poses risk to economyFDA panel to consider Merck’s Covid antiviral pillBiden says he doesn’t expect more travel restrictions, lockdownsFTC orders Walmart, Amazon to provide supply chain information

Dow futures declined roughly 350 points, or about 1%, on Tuesday as investors reassessed risks associated with the new Covid omicron variant. S&P futures fell nearly 1% and Nasdaq futures dropped 0.5%.

Weighing stocks, Moderna CEO Stephane Bancel stepped up comments he made Monday on CNBC’s “Squawk Box,” telling the Financial Times he expects a “material drop” in current vaccine effectiveness against omicron.In addition, preliminary tests of current Covid antibody drug cocktails from Regeneron and Eli Lilly indicated less effectiveness against the new variant, according to The Wall Street Journal.

Stocks saw a rebound Monday, with the Nasdaq up nearly 1.9%, the S&P 500 rising 1.3% and the Dow Jones Industrial Average up almost 0.7%. Wall Street was coming off a holiday-shortened session Friday, during which all three benchmarks dropped more than 2% as omicron became known. Heading into the last day of November, the Dow was lower for the month, while the S&P 500 and Nasdaq were higher for the month.

Federal Reserve Chairman Jerome Powell, according to prepared remarks, is set to tell a Senate Banking Committee hearing Tuesday he believes the omicron variant and a recent uptick in coronavirus cases pose a threat to the U.S. economy and muddle an already-uncertain inflation outlook. “Greater concerns about the virus could reduce people’s willingness to work in person, which would slow progress in the labor market and intensify supply-chain disruptions.” Treasury Secretary Janet Yellen joins Powell for their quarterly report to Congress as part of the March 2020 Covid economic relief legislation. They go before the House Financial Services Committee on Wednesday.

A panel of expert advisors to the Food and Drug Administration are expected to vote Tuesday on whether to recommend authorization of Merck‘s antiviral Covid pill. The U.S. drugmaker reported Friday that the medicine’s efficacy in reducing hospitalizations and deaths dropped to 30% with data available from more than 1,400 patients in its late-stage study. It had reported about a 50% reduction a month ago using data from 775 patients. Analysts said they still expect the Merck drug and a similar oral treatment from Pfizer to be authorized as important therapeutic tools that can be taken at home as soon as Covid symptoms arise.

President Joe Biden on Monday said he doesn’t expect the U.S. to impose additional travel restrictions to stem the spread of omicron. The U.S. on Monday began to temporarily bar visitors from South Africa, where scientists first reported the strain, and from Botswana, Zimbabwe, Namibia, Lesotho, Eswatini, Mozambique and Malawi. The degree of the variant’s spread will determine whether more travel restrictions are necessary, Biden said at a news conference. “I don’t anticipate that at this point,” he said. The president also said he doesn’t think lockdowns are necessary.

The Federal Trade Commission is investigating whether supply chain disruptions are hurting consumers with higher prices. The agency has ordered Walmart, Amazon and other major food suppliers to give detailed information about the situation. The goals of the study are to determine if supply chain problems have led to particular bottlenecks, anti-competitive practices or higher prices, the FTC said in a statement. The probe comes as the Biden administration battles a surge in inflation.

— Reuters contributed to this report. Follow all the market action like a pro on CNBC Pro. Get the latest on the pandemic with CNBC’s coronavirus coverage.