Updated from 4:32 p.m. EST

Amgen

(AMGN) - Get Report

reported a 6% increase in adjusted fourth-quarter earnings Monday, in line with Wall Street estimates, and guided to modest 4% earnings growth in 2009 as the company prepares to launch a new, potentially blockbuster, osteoporosis drug.

The Thousand Oaks, Calif.-based biotech firm reported net income for the fourth quarter of $961 million, or 91 cents per share, compared to net income of $835 million, or 76 cents a share, in the year-ago quarter.

On an adjusted basis, Amgen earned $1.06 a share, matching the Street's consensus estimate, according to Thomson Reuters.

Fourth-quarter revenue was flat at $3.75 billion, falling short of the consensus forecast of $3.79 billion.

For 2009, Amgen forecast adjusted earnings per share in the range of $4.55 to $4.75, which brackets the current 2009 consensus earnings estimate of $4.67 a share. The company guided to total revenue in the range of $14.8 billion to $15.2 billion, below current consensus of $15.39 billion.

Amgen is anticipated to receive approval for and launch a new osteoporosis drug, denosumab, later this year. Denosumab, administered by injection once every six months, has the potential to be Amgen's next blockbuster (read: billion-dollar-plus) drug.

Launching denosumab will require considerable investment on Amgen's part, however, which is one reason why the company is expected to spend more money and boost earnings by only a modest amount in 2009.

Amgen is hoping that denosumab will also be used to treat cancer patients and is running phase III clinical trials with results expected in the second quarter.

Turning back to Amgen's fourth-quarter results, worldwide sales of the anemia drug Aranesp totaled $706 million in the quarter, a 15% drop from $827 million sales in the year-ago quarter and well below investor expectations. Aranesp sales in the U.S. fell 22% year over year to $361 million.

Amgen warned of a 20% reduction in worldwide Aranesp sales on its third-quarter conference call but offered no guidance on how quickly that decline would occur. Aranesp sales have fallen over the past two years due new safety-related label restrictions mandated by regulators in the U.S. and Europe. Less expensive copycat versions of Aranesp - so-called biosimilars - are also being marketed by competitors in Europe.

Turning to other products, Amgen reported $646 million in worldwide sales of Epogen, the company's other anemia drug, as well as $913 million in sales of Enbrel, used to treat psoriasis, rheumatoid arthritis and other auto-immune diseases.

Worldwide sales of the infection-fighting drugs Neupogen and Neulasta totaled $1.18 billion million in the quarter.

Investors to date have largely accepted a slowdown in Aranesp sales, choosing to look ahead to earnings acceleration in 2010 fueled by denosumab. Amgen shares rose 24% in 2008, making the stock (along with Genentech) the best performing big-cap biotech stock of 2008.

Amgen shares closed Tuesday up $1.40, or 2%, to $54.59. Shares were down about 2% in after-hours trading.

Fellow big-cap biotech firm

Genentech

(DNA)

reported weaker-than-expected fourth-quarters earnings Jan. 15.

Gilead Sciences

(GILD) - Get Report

reports Tuesday and

Celgene

(CELG) - Get Report

reports Thursday.

Adam Feuerstein writes regularly for TheStreet.com. In keeping with TSC's editorial policy, he doesn't own or short individual stocks, although he owns stock in TheStreet.com. He also doesn't invest in hedge funds or other private investment partnerships. Feuerstein appreciates your feedback;

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