Purpose: Anemia is a common morbidity of advanced prostate cancer, and prostate cancer treatment and has been associated with a worse overall survival and reduced quality of life in patients with prostate cancer. We sought to determine if infrequent dosing of darbepoetin alfa is safe and effective in treating anemia in patients receiving systemic therapy for prostate cancer.
Patients and methods: Sixteen patients with histologically confirmed prostate cancer with bone metastases on androgen deprivation therapy with or without chemotherapy; and a baseline hemoglobin (Hb) < or = 12 g/dL (amended to < or = 11 g/dL) were enrolled. The primary endpoints were the proportion of patients who had a baseline Hb > or = 12.5 g/dL and the proportion whose baseline Hb increased by > or = 1 g/dL. Patients were initially treated with 300 microg of darbepoetin alfa every 4 weeks. The dose was increased to 500 microg, 800 microg, and 1000 microg at each subsequent visit if the baseline Hb was not at target and had not increased by > or = 1 g/dL during the previous 4 weeks. Treatment was planned for 6 months.
Results: Treatment was well tolerated with no grade > or = 3 toxicities. Fourteen patients were assessable. The median Hb at study entry was 10.7 g/dL (range, 8.4-12). Serum Hb increased by > or = 1 g/dL in 10 patients (71%; 95% confidence interval, 42%-92%) and 7 patients (50%; 95% confidence interval, 23%-77%) reached an Hb of > or = 12.5 g/dL after treatment with doses that ranged from 300 microg to 1000 microg.
Conclusion: Darbepoetin alfa administration every 4 weeks is feasible and well tolerated. Target Hb increases were achieved in approximately half of the patients and required doses that ranged from 300 microg to 1000 microg.