Successful alemtuzumab retreatment in progressive B-cell chronic lymphocytic leukemia: a multicenter survey in 30 patients
Although retreatment with alemtuzumab in relapsing B-cell chronic lymphocytic leukemia (CLL) may be beneficial, there has thus far been no thorough analysis available on this topic. Data were collected from 30 chemotherapy-pretreated patients with progressive CLL who had received alemtuzumab twice in consecutive, distinct therapy lines. The median dose of alemtuzumab retreatment was 402 mg (range, 43–1,090 mg). Retreatment with alemtuzumab induced an overall response rate of 47%. From the start of alemtuzumab retreatment, median progression-free survival (PFS) and overall survival (OS) were 6.3 and 20.0 months, respectively. Response rates, PFS and OS upon alemtuzumab retreatment were correlated with response to initial alemtuzumab treatment, the time interval between the initial course of alemtuzumab and start of retreatment, and the hemoglobin concentration prior to retreatment. Reported toxicities from 24 cases included infections (50%), febrile reactions upon alemtuzumab administration (38%), exanthema (21%), and grade 4 neutropenia (13%) and thrombocytopenia (17%). We conclude that alemtuzumab retreatment represents an effective and tolerable therapeutic option for selected patients with CLL.