The Food and Drug Administration has approved Epoetin alfa, a genetically engineered form of the protein erythropoietin, to treat the anemia that some patients with AIDS or patients who are at earlier stages of infection with the AIDS virus experience while taking zidovudine, commonly called AZT.
The anemia -- a lack of red blood cells -- has been so severe that some patients have had to abandon their AZT therapy. In other cases, anemia-weakened patients have required regular blood transfusions.
A protein formed in the kidneys, erythropoietin, or EPO, stimulates the production of red blood cells. To make quantities sufficient for treatment, scientists have used recombinant DNA techniques to splice the gene that keys the protein's production into a laboratory cell line.
"Erythropoietin may help patients with AIDS or AIDS-related conditions stay on life-prolonging AZT therapy," HHS Secretary Louis W. Sullivan, M.D., said.
Erythropoietin's ability to elevate or maintain red blood cell level production and to reduce the need for transfusions in the treatment of anemia associated with chronic renal failure led to its approval for this indication in June 1989.
While erythropoietin was being investigated for an AIDS indication, FDA in June 1989 permitted the drug to be made widely available to patients on AZT through a "treatment IND" protocol. (IND stands for investigational new drug.) This FDA program allows patients with serious or life-threatening conditions to get experimental drugs that have shown significant promise.
Today's approval of erythropoietin was based on data from clinical studies involving 297 AIDS patients who had experienced severe anemia from zidovudine. Placebo-controlled trials in ll8 of these patients who had low EPO levels resulted in a 40 percent reduction in transfusions for Epoetin-treated patients during a three month period. It was concluded that patients with relatively low levels of naturally occurring erythropoietin may benefit from this new treatment.
Very few adverse reactions have been associated with the use of erythropoietin for this indication. The most frequently reported adverse reactions experienced by patients include fever, headaches and fatigue.
Amgen Inc. of Thousand Oaks, Calif., manufactures the product and did much of the initial work in developing erythropoietin. The product will be marketed under an agreement with Ortho Pharmaceutical Corp. of Raritan, N.J. which sponsored the clinical trial and treatment IND for erythropoietin in AIDS patients. Amgen will market Epoetin alfa using the trade name Epogen. Ortho will market the product under the trade name Procrit.
HHS Assistant Secretary for Health James O. Mason, M.D., who heads the Public Health Service, said, "This is the seventh product approved by FDA for the treatment of AIDS or AIDS-related conditions. These products are extending the lives of people with AIDS."
The drugs approved are AZT for treating infection with the AIDS virus, ganciclovir for the treatment of sight-threatening CMV retinitis, aerosolized pentamidine for use in preventing the occurrence and reoccurrence of Pneumocystis carinii pneumonia, the injectable form of pentamidine for the treatment of Pneumocystis carinii pneumonia, two recombinant human alfa interferons for the treatment of Kaposi's Sarcoma, and fluconazole for the treatment of candidiasis and cryptoccocal meningitis.
The new Commissioner of Food and Drugs David A. Kessler, M.D., said, "FDA has been giving highest priority to AIDS products, reviewing AZT, for example, in less than four months. Today's approval is just another example of the agency's commitment to streamlining the drug development process for all AIDS-related therapies."