Biotech giant Amgen, which said earlier on Thursday that it would pay $1.2 billion for leukemia drugmaker Micromet, reported fourth-quarter earnings that missed analyst expectations.

The Thousand Oaks-based company said fourth-quarter profits fell 8.5 percent to $934 million, or $1.08 per share, on lower sales of its anemia drugs, higher taxes, and higher costs for drug production, sales and administration. Total sales during the quarter increased 3 percent to $3.9 billion.

The quarterly earnings missed the estimated average of 23 analysts compiled by Bloomberg News by 2 cents.

For the full year, the company reported profits of $3.7 billion, or $4.04 per share, down 20 percent from $4.6 billion, or $4.79 per share in 2010. Revenue was up 3 percent to $15.6 billion.

“We exited 2011 with good momentum, and the outlook for 2012 is even stronger,” outgoing CEO Kevin Sharer said in an earnings release. “Our acquisition of Micromet, announced today, further builds our innovative oncology therapeutics pipeline and capabilities.”

Earlier Thursday, Amgen announced that it planned to $11 per share for Maryland-based Micromet. That deal is expected to close in the first quarter.

Amgen said 2012 earnings will likely be in the $5.90 to $6.15 per share range. According to Bloomberg data, analysts had expected a 2012 forecast of $5.94 per share.

Amgen shares were down 1.6 percent to $68.08 after announcing its results.