Alemtuzumab, a humanized anti-CD52 monoclonal antibody, is used in patients with refractory chronic lymphocytic leukaemia (CLL). We report results in health care with alemtuzumab on consecutive, advanced-stage patients from a well-defined geographical region. Records from 1,301 patients (Stockholm-Cancer-Registry 1991-2010) identified 56 relapsed/refractory patients treated with alemtuzumab. Median age was 69 years, 88 % had advanced Rai-stage with median 3 prior therapies. One fourth had bulky lymphadenopathy and 73 % were refractory to purine analogues. Median treatment length was 11.6 weeks. Median cumulative dose was 930 mg, significantly higher (p = 0.0277) for responders. Overall response-rate (ORR) was 43 %; 32.5 %, 50 % and 87.5 % in the Refractory, Purine analogue relapsed and Relapsed/Other subgroup, respectively. Response rate was significantly associated with subgroup (p = 0.0104). Good performance status (PS) was associated with better response rate (p = 0.0227). Median time-to-treatment-failure (TTF) (months) was 7.8 months, significantly (p < 0.0001) longer for responders (13.4) Major infections occurred in 36 %. Median overall survival was 22.5 months (range 0.4-74.3). Positive predictive factors were good PS (p < 0.0001) and fewer previous therapies (p = 0.0038). Twenty percent were retreated with alemtuzumab with an ORR of 54.5 %, and a TTF of 7.1 months. A high cumulative dose/longer duration of therapy and a relatively high response rate was observed compared to previous reports. Optimal patient identification and management may result in avoidance of early discontinuation and possibly better outcomes.