Novo Nordisk shares fell nearly 30% in the fourth quarter on disappointing clinical trial data, and other concerns. Bank of America addresses the company’s earnings and more.

U.S.-listed shares of Danish pharmaceutical giant Novo Nordisk A/S (NYSE:NVO) are up 3.5% premarket, following a bull note from UBS. The analyst in question upgraded NVO to "buy" from "neutral," citing strong demand for GLP-1 medications and calling it "the most exciting growth story in European pharma."

Amidst a race with its competitors to produce the next smash-hit weight loss drug, Novo Nordisk 's ( NVO 0.15%) stock crashed by 19% on Dec. 20, after the company reported results from a late-stage clinical trial that it framed as a success.