This prospective, open-label, multicenter trial evaluated the effects of once-weekly (qw) epoetin alfa on quality of life (QOL) and hemoglobin (Hb) levels in anemic human immunodeficiency virus (HIV)-infected adult receiving antiretroviral therapy. A total of 650 patients with Hb < or = 11 g/dl received epoetin alfa 40,000 U qw subcutaneously, with dose escalation to 60,000 qw if Hb increase was <1 g/dl after 4 weeks. The linear Analog Scale Assessment (LASA) overall QOL score, LASA energy score, and LASA activity score each significantly improved from baseline to final measurement (p < 0.0001 for each parameter). Improvements in the Medical Outcomes Study (MOS)-HIV physical and mental health summary scores were also significant (p < 0.0001), and coincided with Hb increases. Mean Hb increased from baseline to final measurement by 2.5 g/dl (95% CI: 2.3, 2.6 g/dl; p < 0.0001). Objective hematological response rate, defined as a > or = 1 g/dl Hb increase from baseline to week 8, was 86%. Hemoglobin increased significantly in all subgroups of race, zidovudine use, CD4+ cell count, and viral load. Once-weekly epoetin alfa was well tolerated. Once-weekly epoetin alfa is effective in improving QOL and Hb measures.