8161 Background: to prospectively evaluate the effectiveness of two different epoetin alfa dosing to improve hemoglobin (Hb) levels in chemotherapy (CT) patients (pts). Methods: A total of 290 pts with nonmyeloid malignancies who received CT were included into this prospective, multicenter, open-label and nonrandomized controlled cohort study. A cohort of 190 pts received epoetin alfa 10,000 IU three-times weekly (t.i.w.) and a second cohort of 100 pts received 40,000 IU once weekly (q.w.). Epoetin alfa dose could be increased to 60,000 IU/w after 3 weeks depending on Hb response. The efficacy variables were hematopoietic response (defined as an increase in Hb ≥ 2 g/dL or achievement of a Hb level ≥ 12 g/dL); mean change in Hb level; rate of pts who needed increase epoetin alfa dose; number of treatment’s weeks and the rate of pts transfused. Multivariate analyses using a logistic and lineal regression model were performed to provide a measure of treatment effect adjusted for those variables that were reported as significantly different between both groups. Results: There were no significant differences in the demographic and baseline clinical characteristics between the two treatment groups except baseline endogenous EPO. In the multivariate analysis, no significant differences were found regarding to Hematopoietic response rate (69.9% vs 67.7% for t.i.w vs q.w. group; p=0.224); mean change in Hb (0.5 g/dL [95% CI 0.3–0.7] vs 0.6 g/dL [95% CI 0.3–0.9] for t.i.w vs q.w dosing; p=0.533) and the rate of pts transfused (8.2% vs 8.6% for t.i.w vs q.w group; p=0.774). Epoetin alfa dose was doubled in 34.9% of pts in t.i.w cohort versus 6.8% in q.w. cohort (p=0.0001). Mean number of weeks of epoetin alfa treatment was similar in both groups (7 w [95% CI 6.3–7.7] vs 6.5 w [95% CI 5.7–7.4] for t.i.w vs q.w dosing; p=0.095), although mean weeks with double dose was higher in t.i.w group (1.9 w [95% CI 1.4–2.5] than in q.w. gropu (0.3 w [95% CI 0.03–0.5] (p=0.0001). Conclusions: once-weekly 40.000 U of epoetin alfa is similar to 10.000 U three-times weekly to increase Hb levels but with a lower need of dose increased and, probably, with a better cost-effectiveness. No significant financial relationships to disclose.