19588 Background: Anemia is the most frequent hematological complication of cancer. Epoetin beta (E), an effective treatment of anemia in patients with solid tumors (ST) was administered three-times weekly. However, the QW regimen used in patients with hematological malignancies would be more convenient and may improve patient compliance. The aim of our study was to evaluate efficacy and safety of E 30 000 IU QW in patients with ST. Methods: This study was an open-label, single-arm, multicenter trial carried out in 87 French centers between December 2003 and August 2005. Eligibility criteria were: informed consent, age =18 yrs, WHO performance status 0–2, malignant ST or non-myeloid hematological malignancy, on-going chemotherapy and anemia: hemoglobin (Hb) <12 g/dl. E 30 000 IU QW was administered SC for up to 16 weeks. Follow-up visits were scheduled after each chemotherapy cycle. Primary endpoint was Hb response defined as an Hb increase of =2 g/dl (whatever the baseline Hb level) and/or an achievement of Hb level of =12 g/dl or 13 g/dl (patients with Hb levels <11 g/dl or >11 g/dl at baseline respectively). Delay of Hb response, transfusion requirement, mood and cognitive functions were also assessed. Here we focus specifically on the subgroup of patients with ST. Results: In total, 365 patients with ST were included. The most frequent cancer sites were: lung (102 pts) and breast (86 pts). Median Hb level at baseline was 10.4 g/dl [7.9–12.3]. At endpoint, median Hb level increased to 12.5 g/dl [8.4–15.0]. Hb response rate (RR) was: 61% (IC95: 55–66%), 50% (IC95: 38–55%) in patients treated with platinum based regimen and 72% (IC95 : 62–76%) in patients treated without platinum. RR was 54% in lung (IC95: 44–64%), 76% in breast (IC95: 67- 85%). E treatment was well tolerated. Thromboembolic events occurred in 7% of patients, a rate consistent with information provided in the current label for E. Conclusion: Epoetin beta 30 000 IU once weekly is effective and well tolerated in anemic patients with solid tumor treated with chemotherapy. Once weekly treatment offers a convenient therapy which will improve patient compliance. [Table: see text]