Biogen Inc. (BIIB – Free Report) reported fourth-quarter 2017 earnings per share of $5.26, which missed the Zacks Consensus Estimate of $5.44 by 3.3%. Earnings, however, rose 4% year over year as higher revenues made up for higher operating costs.

Sales came in at $3.31 billion, up 15% from the year-ago period. Sales also surpassed the Zacks Consensus Estimate of $3.07 billion by 7.6%.

We remind investors that last year Biogen spun off its hemophilia business into a new company called Bioverativ (BIVV – Free Report). Sanofi (SNY – Free Report), earlier this week, announced that it has offered to buy Bioverativ for $11.6 billion.

Quarter in Detail

Biogen’s multiple sclerosis (MS) revenues were $2.3 billion (up 5%) in the quarter including approximately $77 million in royalties on the sales of Roche’s (RHHBY – Free Report) MS drug, Ocrevus. Per a deal with Roche, Biogen is entitled to receive royalties on U.S. sales of Ocrevus.

In the quarter, MS sales in the United States included inventory buildup of $40 million, which benefited revenues.

Oral MS drug, Tecfidera’s sales increased 7% year over year and 1% sequentially to $1.08 billion. The other MS drug, Tysabri’s sales decreased 2% year over year and 1% sequentially to $463 million.

Combined interferon revenues (Avonex and Plegridy) in the fourth quarter were $645 million, down 6% from the year-ago period. Avonex revenues declined 8% from the year-ago period to $520 million. Plegridy contributed $125 million to fourth-quarter 2017 revenues, flat year over year as well as sequentially.

U.S. Interferon revenues are experiencing declining trends due to patients transitioning to other oral MS therapies as well as due to higher discounts and allowance.

Zinbryta, launched in collaboration with AbbVie, contributed $12 million to revenues in the fourth quarter compared with $14 million in third-quarter 2017.

Newly launched Spinraza brought in revenues of $363 million in the fourth quarter, registering growth of 34% sequentially.