Updated from 4:43 p.m. EDT

Amgen ( AMGN) reported a 4% drop in adjusted first-quarter earnings Thursday on lower revenue, both missing Wall Street estimates, as the global recession took its toll on the company's financial performance.

The Thousand Oaks, Calif.-based biotech firm reported net income for the first quarter of $1.01 billion, or 98 cents per share, compared to net income of $1.1 billion, or $1.01 a share, in the year-ago quarter.

On an adjusted basis, Amgen earned $1.08 a share, below the Street's consensus estimate of $1.15 a share, according to Thomson Reuters.

First-quarter revenue fell 8% to $3.3 billion, short of the consensus forecast of $3.63 billion.

Amgen lowered its 2009 revenue forecast to the range of $14.4 billion to $14.8 billion from its previous guidance of $14.8 billion to $15.2 billion. The company continues to expect adjusted earnings in 2009 to be in the range of $4.55 a share to $4.75 a share.

"Our first quarter sales were affected by the continued deterioration of the global economy which has led to changes in patient and physician behavior," said Amgen CEO Kevin Sharer, in a statement.

Worldwide sales of the anemia drug Aranesp totaled $626 million in the quarter, an 18% drop from $761 million sales in the year-ago quarter and below investor expectations. Aranesp sales in the U.S. fell 28% year over year to $292 million.

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.

Sales of Enbrel, used to treat psoriasis, rheumatoid arthritis and other autoimmune diseases, fell 20% in the first quarter to $758 million. Analysts were looking for sales of around $900 million.

Amgen blamed the decrease in Enbrel sales partly on wholesale inventory changes made during the first quarter of last year, but also due to lower demand for the drug due to the economy. Last week, Abbott ( ABT) reported lower-than-expected sales of Humira, a competing drug.

Turning to other products, Amgen reported $565 million in worldwide sales of Epogen, the company's other anemia drug. Worldwide sales of the infection-fighting drugs Neupogen and Neulasta totaled $1.07 billion million in the quarter.

Amgen shares were falling 1.8% to $46 in afterhours trading.
At the time of publication, Feuerstein's Biotech Select model portfolio was long Amgen.

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