Stocks making the biggest moves premarket: Moderna, Royal Caribbean, Cerner and others

Check out the companies that are making news.

Moderna said a booster dose of its Covid-19 vaccine increased protection against the omicron variant by 37 times. Other vaccine makers are also seeing gains, with Pfizer, BioNTech, and Novavax all seeing gains.

Royal Caribbean's ship docked in Miami with 48 cases of Covid, putting more pressure on cruise stocks. Royal Caribbean, Carnival and Norwegian Cruise Line all fell in premarket trading.

Omicron concerns are weighing on the airline stocks, with United Airlines (UAL) falling 2.9%, American Airlines (AAL) sliding 2.8%, Delta Air Lines (DAL) falling 2.8%, Southwest (LUV) down 2.3% and JetBlue (JBLU) losing

The price of the Alzheimer's drug Aduhelm will be cut by 50% in order to improve access to the treatment.

According to CNBC's David Faber, the medical records technology provider will announce a deal today to be acquired by Oracle in an all-cash transaction "in the mid-$90s" per share. The Wall Street Journal reported that the two sides were close to an agreement. In premarket trading, it was up 1.7%.

The cannabis producer slid 3.4% in premarket action after it was lowered to "underweight" from "neutral".

Sunrun's stock plummeted in the premarket after KeyBanc lowered its rating to "sector weight" from "overweight". There are proposals in California that would reduce the benefits of net metering for solar power customers.

AT&T was upgraded to "overweight" from "neutral" byBarclays, based on a better broadband outlook for telecom companies than for cable providers. AT&T was up in the premarket.

BillerudKorsns will acquire Verso in a deal worth $27 per share in cash. Verso surged in premarket trading.

The maker of stun guns and body cameras saw its stock jump in the premarket after a number of stock purchases by company executives.

The drugmaker's shares fell 4.2% in premarket trading after it said it wouldn't be able to meet demand for its weight-loss drug Wegovy in the U.S.

The spelling of Aduhelm has been changed.