Amgen Stock Levels Out After Fall at News of Rival’s Patent

The stock of Amgen, a Thousand Oaks biotechnology company, stabilized somewhat after falling sharply last week on news that a rival biotech firm, Genetics Institute, received a U.S. patent on a protein that Amgen also is developing. After tumbling $6.50 a share to $31.75 after the Genetics announcement Wednesday, the stock recovered 75 cents in the next session but then lost $1 a share, to $31.50, in national over-the-counter trading Monday.

The stock drew some support when analysts said that Amgen appeared to have the lead in the patent race for another form of the protein, called erythropoietin, which helps control production of red blood cells. The result might be a cross-licensing agreement between the companies, the analysts said.

Amgen also asserted it is ahead in clinical trials of the drug and that it expects to win “the dominant patent rights” for making the substance.

Separately, Amgen said it completed a private placement of $84 million of limited partnership units in its Amgen Clinical Partners L. P. The limited partnership said it would use the proceeds for research on new therapeutic products, including a separate protein--called granulocyte colony stimulating factor, or G-CSF--that stimulates defenses against bacteria.