Doctors who use biologic drugs to treat anemia in accordance with the guidelines for which they were approved need have little concern over their safety, according to doctors attending the American Society of Clinical Oncology scientific meeting in Chicago.

The drugs -- Amgen's Aranesp and Epogen and Johnson & Johnson's Procrit -- have attracted attention in recent weeks as a result of reports that the risk of death or blood clots is higher in patients who received higher doses of the biologic drugs or who were given them "off-label" for unapproved conditions.

Dr. Charles Bennett, an oncologist at Northwestern University and principal researcher on a study presented at the ASCO meeting, said when the anemia drugs are prescribed as approved by the Food and Drug Adminisration, "there are no hidden safety signals."

"We break no new ground," he told attendees at the ASCO meeting.

Dr. Jeffrey Crawford, a professor of oncology at Duke University Medical Center, said he feared studies that showed an increased risk of death in cancer patients not on chemotherapy which already have led to an FDA "black box" warning on the anemia drugs may cause patients needless worry.

He acknowledged some patients taking the drug "off-label" may face a higher risk, but said that for the 90 percent of patients using the drugs as approved, "I feel very confident with the current guidelines of use."