A total of 27 patients with a median age of 65 (range 48–83) years were treated. The median disease duration was 6 years (range 3–15), with a median number of three previous treatments (range 0–6). 22·2% of patients were Rai stage I–II, the remainder stage III–IV. There were no Binet stage A patients, with 25% being Binet stage B and 75% Binet stage C. Cytogenetic data was available on 24 patients. Six patients had no discernible abnormality, two patients had trisomy 12, two patients del13q14.3, seven patients del11q22.3 and six patients del17p13.1. Twelve patients had bulky refractory disease, four had double refractory disease, five had both bulky refractory and double refractory disease and six were considered unsuitable for Alemtuzumab therapy. Three patients died after receiving one or two infusions. These were classified as non-responders. 11/12 patients, who were red cell dependent prior to Ofatumumab therapy, became transfusion independent. The median time to reach a haemoglobin level >110 g/l was 21 days. Twelve patients had a platelet count 100 × 109/l (Table I). The median follow up was 8·0 months (range 1–23 months) from the onset of the Ofatumumab infusions. Three patients achieved a clinical complete remission (CR) and 10 patients a partial remission (PR). Nine patients had progressive disease, two stable disease and three died. The overall response rate was therefore 48% (13/27). The median time-to-next-treatment (TTNT) when calculated from the first Ofatumumab infusion was 5·5 months (range 1·5–18) (Table I and Fig 1).