Biogen Inc (NASDAQ:BIIB) shares fell Wednesday after the company reported declining fourth-quarter sales and revealed that it expects that trend to continue in 2023. The company expects sales to decline by mid-single digit percentages in 2023 after they fell nearly 7% to $2.54 billion in the fourth quarter. Biogen also forecast full-year adjusted profit of $15 to $16 per share, compared with analysts' estimates of $15.72 per share. Shares of the company were down 4% to $277.40 Wednesday afternoon. In the fourth quarter, the company reported revenue that topped analyst expectations of $2.44 billion. Revenue fell year-over-year, though thanks in part to declining sales of its drug Tecfidera.