Patients with relapsed chronic lymphocytic leukemia (CLL) and high-risk features, such as fludarabine refractoriness, complex karyotype, or abnormalities of chromosome 17p, experience poor outcomes after standard fludaradine-based regimens. Alemtuzumab is a chimeric CD52 monoclonal antibody with activity in CLL patients with fludarabine-refractory disease and 17p deletion. We report the outcome for 80 relapsed or refractory patients with CLL enrolled in a phase 2 study of cyclophosphamide, fludarabine, alemtuzumab, and rituximab (CFAR). All patients were assessed for response and progression according to the 1996 CLL-working group criteria. For the intention-to-treat analysis, the overall response rate was 65%, including 29% complete response. The estimated progression-free survival was 10.6 months and median overall survival was 16.7 months. Although we noted higher complete response in high-risk patients after CFAR compared with a similar population who had received fludarabine, cyclophosphamide, and rituximab as salvage therapy, there was no significant improvement in progression-free survival and overall survival appeared worse. CFAR was associated with a high rate of infectious complications with 37 patients (46%) experiencing a serious infection during therapy and 28% of evaluable patients experiencing late serious infections. Although CFAR produced good response rates in this highly pretreated high-risk group of patients, there was no benefit in survival outcomes.