Aranesp, Epogen and Procrit already carry a black box warning, so ordered by the US Food and Drug Administration (FDA) last year. The latest studies, made public in the first week of 2008, will put even more scrutiny on the Amgen products. The FDA has said that it will hold a meeting early this year to review the safety of the drugs in cancer patients, but so far a date has not yet been set.
Amgen, a biotech company based in Thousand Oaks, California, manufactures all three anemia drugs. Amgen markets Aranesp and Epogen directly, whereas Procrit is marketed by Ortho Biotech LP, a subsidiary of Johnson & Johnson. Known generically as erythropoietin-stimulating agents or ESAs, the anemia drugs are bioengineered versions of a natural protein manufactured in the kidney that stimulates bone marrow to produce more red blood cells. Cancer and dialysis patients use injectable ESAs to treat anemia and boost energy.
Concern has been steadily increasing after a series of studies over the years—six in total—revealed that the trio of anemia drugs can contribute to heart attack, stroke, heart failure and the growth of cancerous tumors.In concert with the FDA adding the black box warning last year, the federal Medicaid agency imposed limits on the dosages it would reimburse.
Now, two new studies have added fuel to the fire. One study involved 733 female chemotherapy patients, who had undergone radiation prior to surgery for breast cancer. At the end of a three-year term, it was determined that 14 per cent of women who received Aranesp to combat their anemia had died, as compared with 9.8 per cent of patients who had not received Aranesp.
In another trial, this one conducted by the National Institute's Gynecologic Oncology Group, patients receiving chemotherapy and radiation for advanced cervical cancer were given blood transfusions, or Procrit as needed. After three years, 58 per cent of patients having taken Procrit were alive, and free of cancer growth. However, this number pales in comparison to the 66 per cent of patients who did not take Procrit.
To its credit, the manufacturer notified federal regulators of the study findings immediately, even though it knew there would be a price to be paid on the business end.
Amgen has already been feeling the heat. The company's stock has fallen to a five-year low since the summer with a corresponding loss of $17 billion dollars in value. Amgen was forced to reduce its work force by 14 per cent in 2007. Sales have been dropping since the appearance of the black box warning last year, and these two latest studies will only serve to worsen that erosion.
Aranesp and Epogen accounted for more than half of Amgen's net sales. The bets on Wall Street are on the company continuing to lose revenue through 2008, with limited stock growth through 2010.
Last year the FDA issued an alert informing medical professionals and patients about cases of severe anemia and pure red cell aplasia (PRCA) in patients taking ESAs. The inference is that Erythropoietin drugs are making patients worse rather than better.
The new black box warning label, announced by the FDA on March 9th last year, warned of increased risk for blood clots, heart attacks, and death in kidney patients in concert with higher-than-recommended doses. At recommended dosage levels, the three drugs carried an increased risk of death amongst cancer patients who were not treated with chemotherapy. Also present was a risk of blood clot for patients who had undergone orthopedic surgery.
The existing black box label warns doctors to monitor levels of red blood cells, and to use the lowest dose possible.
Amgen has pledged it will release any new safety data, and will work closely with the FDA on further changes to product labeling, if needed. Labels have been revised to update safety information on three other occasions: 1997, 2004 and 2005. The safety and efficacy of the three anemia drugs were discussed four years ago during a session with the Oncologic Drugs Advisory Committee.
Amgen sales were reported at $5 billion last year.
