Shares in biotech firm Amgen Inc. dropped more than 2 percent Thursday after an analyst cut his profit estimates for the company, saying use of Amgen’s anemia drugs will be restricted.

A Food & Drug Administration panel will meet next month to discuss the safety of prescribing certain anemia drugs for cancer patients. Analyst Jim Reddoch at Friedman Billings Ramsey said in his latest research report that he believes the panel will vote to limit use of the drugs and the FDA will follow the panel’s recommendations.

The drugs in question are called erythropoiesis-stimulating agents, or ESAs, and include Amgen’s Aranesp and Epogen as well as Johnson & Johnson’s Procrit. The drugs are used to treat anemia caused by chemotherapy and kidney disease. Aranesp and Epogen are Amgen’s biggest-selling products.

A recent study, published in the Journal of the American Medical Association, found patients using ESAs had a 10 percent increased risk of death and were also more likely (57 percent) to develop blood clots in the leg and lungs, the study said.

Last month, Amgen reported in its fourth quarter earnings that sales of Aranesp slumped 12 percent during 2007 to $3.61 billion while sales of Epogen dropped 1 percent to $2.49 billion.

Shares in the Thousand Oaks-based firm were down 2.1 percent to $45.63 in early trading Thursday on the Nasdaq. The price has declined 32 percent since a year ago.