Every-Three-Week Administration of Darbepoetin Alfa for Anemia
Every-Three-Week Administration of Darbepoetin Alfa for Anemia
Purpose: The effectiveness of every-three-week administration of darbepoetin alfa in women with chemotherapy-associated anemia was evaluated.
Methods: Women receiving chemotherapy for gynecological tumors who had a hemoglobin concentration of <10 g/dL were recruited from an obstetrics and gynecology service. Study patients received subcutaneous darbepoetin alfa 6.75 µg/kg, followed by 4.5 µg/kg every three weeks for a total of up to six doses. Hematopoietic response and mean changes in hemoglobin concentrations were evaluated. The Functional Assessment in Cancer Therapy-Anemia (FACT-An) survey was self-administered before and after study completion to evaluate the patients' quality of life.
Results: The mean ± S.D. age and weight for the 14 patients recruited (12 of whom were assessable) were 52.1 ± 14 years and 64.6 ± 19.8 kg, respectively. The mean initial and maintenance doses were 442 and 301.6 µg, respectively. The overall hematopoietic response was 64.3%, of which 35.7% were complete and 28.6% were partial. Peak response occurred at weeks 9 and 12. The mean ± S.D. change in hemoglobin concentration was 1.6 ± 1.51 g/dL. Treatment failure was predicted by week 9 (n = 2). Maintenance doses were withheld if a patient's hemoglobin concentration exceeded 12 g/dL (n = 3). The mean ± S.D. point differential for FACT-An pretreatment and posttreatment scores was 5.8 ± 4.71 (n = 6).
Conclusion: Every-three-week administration of subcutaneous darbepoetin alfa produced a complete or partial hematopoietic response in 11 of 14 women with chemotherapy- associated anemia. A quality-of-life indicator generally improved among the 6 patients for whom posttreatment quality-of-life data were available.
Anemia, defined as a hemoglobin concentration of <12 g/dL, is a common complication in patients receiving chemotherapy, with up to 52% of patients with solid tumors developing anemia. Of the 1.24 million people in the United States receiving chemotherapy, nearly 800,000 (64.5%) are anemic. Erythropoiesis is compromised in patients with cancer. The etiology of anemia in cancer patients is multifactorial and can include the pathophysiology of cancer itself and its treatment.
Anemia in cancer patients may be exacerbated by repeated cycles of myelosuppressive chemotherapy or radiation therapy due to the release of cytokines (e.g., interleukin-1, tumor necrosis factor) that is secondary to an inflammatory or neoplastic process. Further, the myelosuppressive effects of chemotherapy reduce erythropoietin production by exerting nephrotoxic effects on the renal tubules and destroying mature hematopoietic cells. Radiation therapy directly damages stem cells in the bone marrow, which also exacerbates anemia.
In July 2002, darbepoetin alfa received marketing approval for the treatment of anemia in patients with nonmyeloid malignancies receiving chemotherapy. It was added to the Sacred Heart Health System (SHHS) formulary in March 2003.
For the treatment of chemotherapy-associated anemia in patients with nonmyeloid malignancies, the recommended subcutaneous dose of darbepoetin alfa is 3 µg/kg/week, the therapeutic effects of which are similar to those of epoetin alfa 150 units/kg thrice weekly. The equivalent subcutaneous dose of darbepoetin alfa to the commonly prescribed 40,000-units weekly subcutaneous dose of epoetin alfa is 3 µg/kg every two weeks. For convenience, a fixed subcutaneous dose of 200 µg every two weeks may be used.
Although they are effective, thrice-weekly or weekly regimens of epoetin alfa can pose an economic burden on patients with persistent anemia during cancer treatment. Ideally, carefully coordinated treatments for anemia in cancer patients receiving concurrent chemotherapy would reduce the number of physician's office visits and maintain optimal compliance to the prescribed cycles of chemotherapy. Therefore, every-three-week administration of darbepoetin alfa may be a plausible goal.
At SHHS, epoetin alfa was extensively prescribed for anemic patients with cancer in 2003. For a 70-kg patient receiving 40,000 units of epoetin alfa as a weekly fixed dose, the acquisition cost was $400.62 in 2003. For 15 weeks of this therapy, the total drug cost was $6009.30. If an initial dose of 6.75 µg/kg of darbepoetin alfa had been used, followed by 4.5 µg/kg every 3 weeks for four treatments, this would have cost $4594.25, about 24% less than epoetin alfa.
In August 2002, the Florida Medicaid Authority replaced epoetin alfa with darbepoetin alfa on the state's preferred drug list. Despite similar efficacy between epoetin alfa and darbepoetin alfa, the change was based on the cost and less frequent administration of darbepoetin alfa. However, continued indiscriminate use of darbepoetin alfa in patients could still pose an economic burden. Early evaluation of hematopoietic values can promote prudent drug use and help determine who is most likely to respond to the drug.
The objectives of this study were to evaluate the hematopoietic response to darbepoetin alfa, evaluate the effects of every-three-week administration, and assess the quality of life using the Functional Assessment in Cancer Therapy-Anemia (FACT-An) scale.
Abstract and Introduction
Abstract
Purpose: The effectiveness of every-three-week administration of darbepoetin alfa in women with chemotherapy-associated anemia was evaluated.
Methods: Women receiving chemotherapy for gynecological tumors who had a hemoglobin concentration of <10 g/dL were recruited from an obstetrics and gynecology service. Study patients received subcutaneous darbepoetin alfa 6.75 µg/kg, followed by 4.5 µg/kg every three weeks for a total of up to six doses. Hematopoietic response and mean changes in hemoglobin concentrations were evaluated. The Functional Assessment in Cancer Therapy-Anemia (FACT-An) survey was self-administered before and after study completion to evaluate the patients' quality of life.
Results: The mean ± S.D. age and weight for the 14 patients recruited (12 of whom were assessable) were 52.1 ± 14 years and 64.6 ± 19.8 kg, respectively. The mean initial and maintenance doses were 442 and 301.6 µg, respectively. The overall hematopoietic response was 64.3%, of which 35.7% were complete and 28.6% were partial. Peak response occurred at weeks 9 and 12. The mean ± S.D. change in hemoglobin concentration was 1.6 ± 1.51 g/dL. Treatment failure was predicted by week 9 (n = 2). Maintenance doses were withheld if a patient's hemoglobin concentration exceeded 12 g/dL (n = 3). The mean ± S.D. point differential for FACT-An pretreatment and posttreatment scores was 5.8 ± 4.71 (n = 6).
Conclusion: Every-three-week administration of subcutaneous darbepoetin alfa produced a complete or partial hematopoietic response in 11 of 14 women with chemotherapy- associated anemia. A quality-of-life indicator generally improved among the 6 patients for whom posttreatment quality-of-life data were available.
Introduction
Anemia, defined as a hemoglobin concentration of <12 g/dL, is a common complication in patients receiving chemotherapy, with up to 52% of patients with solid tumors developing anemia. Of the 1.24 million people in the United States receiving chemotherapy, nearly 800,000 (64.5%) are anemic. Erythropoiesis is compromised in patients with cancer. The etiology of anemia in cancer patients is multifactorial and can include the pathophysiology of cancer itself and its treatment.
Anemia in cancer patients may be exacerbated by repeated cycles of myelosuppressive chemotherapy or radiation therapy due to the release of cytokines (e.g., interleukin-1, tumor necrosis factor) that is secondary to an inflammatory or neoplastic process. Further, the myelosuppressive effects of chemotherapy reduce erythropoietin production by exerting nephrotoxic effects on the renal tubules and destroying mature hematopoietic cells. Radiation therapy directly damages stem cells in the bone marrow, which also exacerbates anemia.
In July 2002, darbepoetin alfa received marketing approval for the treatment of anemia in patients with nonmyeloid malignancies receiving chemotherapy. It was added to the Sacred Heart Health System (SHHS) formulary in March 2003.
For the treatment of chemotherapy-associated anemia in patients with nonmyeloid malignancies, the recommended subcutaneous dose of darbepoetin alfa is 3 µg/kg/week, the therapeutic effects of which are similar to those of epoetin alfa 150 units/kg thrice weekly. The equivalent subcutaneous dose of darbepoetin alfa to the commonly prescribed 40,000-units weekly subcutaneous dose of epoetin alfa is 3 µg/kg every two weeks. For convenience, a fixed subcutaneous dose of 200 µg every two weeks may be used.
Although they are effective, thrice-weekly or weekly regimens of epoetin alfa can pose an economic burden on patients with persistent anemia during cancer treatment. Ideally, carefully coordinated treatments for anemia in cancer patients receiving concurrent chemotherapy would reduce the number of physician's office visits and maintain optimal compliance to the prescribed cycles of chemotherapy. Therefore, every-three-week administration of darbepoetin alfa may be a plausible goal.
At SHHS, epoetin alfa was extensively prescribed for anemic patients with cancer in 2003. For a 70-kg patient receiving 40,000 units of epoetin alfa as a weekly fixed dose, the acquisition cost was $400.62 in 2003. For 15 weeks of this therapy, the total drug cost was $6009.30. If an initial dose of 6.75 µg/kg of darbepoetin alfa had been used, followed by 4.5 µg/kg every 3 weeks for four treatments, this would have cost $4594.25, about 24% less than epoetin alfa.
In August 2002, the Florida Medicaid Authority replaced epoetin alfa with darbepoetin alfa on the state's preferred drug list. Despite similar efficacy between epoetin alfa and darbepoetin alfa, the change was based on the cost and less frequent administration of darbepoetin alfa. However, continued indiscriminate use of darbepoetin alfa in patients could still pose an economic burden. Early evaluation of hematopoietic values can promote prudent drug use and help determine who is most likely to respond to the drug.
The objectives of this study were to evaluate the hematopoietic response to darbepoetin alfa, evaluate the effects of every-three-week administration, and assess the quality of life using the Functional Assessment in Cancer Therapy-Anemia (FACT-An) scale.