Dosage Forms. Injection Solution: 0.025 mg/mL, 0.04 mg/mL, 0.06 mg/mL, 0.1 mg/mL, 0.2 mg/mL, 0.3 mg/mL, 0.15 mg/0.75 mL; SingleJect: 0.025 mg/0.42 mL, 0.04 mg/0.4 mL, 0.06 mg/0.3 mL, 0.1 mg/0.5 mL, 0.15 mg/0.3 mL, 0.2 mg/0.4 mL, 0.3 mg/0.6 mL, 0.5 mg/mL
Common FDA Label Indication, Dosing, and Titration.
1. Anemia due to chemotherapy: 2.25 mcg/kg SQ weekly; or 500 mcg SQ every 3 wk
2. Anemia of chronic renal failure: Epoetin alfa naive patients (not on dialysis), 0.45 mcg/kg IV or SQ once weekly; or 0.75 mcg/kg SQ once every 2 wk
1. Anemia—myelodysplastic syndrome: 500 mcg SQ every 3 wk or 150-300 mcg SQ weekly
MOA. Darbepoetin alfa is a hyperglycosylated analogue of recombinant human erythropoietin. It binds to the erythropoietin receptor on erythroid progenitor cells, stimulating production/differentiation of mature red cells.
Drug Characteristics: Darbepoetin
Medication Safety Issues: Darbepoetin
Drug Interactions: Darbepoetin. None
Adverse Reactions: Darbepoetin
Efficacy Monitoring Parameters. For anemia, titrate dose to avoid transfusion (usually target is to keep hemoglobin >9 g/dL) but discontinue if Hg >10 g/dL. For renal failure, titrate to keep Hg between 10-11 g/dL. Iron studies to ensure adequate iron stores, transferring saturation >20% and ferritin >100 mg/mL.
Toxicity Monitoring Parameters. BP; weight to monitor edema; SCr in renal failure patients; signs and symptoms of thrombosis; cancer progression.
Key Patient Counseling Points. Do not shake, dilute, or expose to light. Refrigerate. Do not combine remainders from different syringes; each syringe is single use. May require several weeks for maximum effect.
Clinical Pearls. Typically administered in hospital infusion and dialysis clinics. In cancer patients with certain tumor types (eg, breast, non-small cell lung, head and neck, etc), epoetin and darbepoetin shortened overall survival, and/or increased risk of tumor progression or recurrence in some clinical studies. Discontinue after the completion of the chemotherapy course and if no response after 8 wk of therapy. Hospitals and healthcare professionals who prescribe and/or dispense darbepoetin to patients with cancer must enroll and comply with the ESA APPRISE oncology program at www.esa-apprise.com. Renal failure patients experienced greater risks for death, stroke, and serious cardiovascular events when administered erythropoiesis-stimulating agents (ESAs) to target hemoglobin levels of 11 g/dL or higher in clinical studies. Not for initial use in children, typically started on erythropoetin and converted to darbepoetin.