The Alemtuzumab Treatment of Refractory to Fludarabine Chronic Lymphocytic Leukemia Patients.

We observed 6 pts (3 male and 3 female). The median age was 56 years old(52-69). 4 of the pts had Rai stage I desease, 1 patient had Rai stage III, 1 had Rai stage IV. We revealed that 4 pts had 17p deletion with high level, 1 patient did not have del 17p, 1 - was not assessed. High level of the expression of CD38+ was determined, the median number was 37,3%(15-82). All pts were pretreated with Chlorambucil, COP, CHOP, FC for 18 months(7-48). All pts were refractory to F. 5 pts received A. monotherapy during median 9 weeks (2-18). Subcutaneous(SQ) A. dose escalation: 3mg-10mg-30mg on days 1,3,5, followed by 30mg Monday, Wednesday and Friday for 17 weeks. 1 patient received 5 courses FluCam(A. 30 mg 1,2,3 days IV after dose escalation 3mg-10mg-30mg, F. 25mg/m2 1,2,3 days). All pts received PCP, herpes and cytomegalovirus(CMV) and fungal prophylaxis as well as CMV viral DNA monitoring.

Responses were based on NCI-WG 1996 criteria. Minimal residual disease (MRD) was measured in peripheral blood and bone marrow aspirate using flow cytometry for CD19+/CD5+/CD23+ lymphocytes.

The efficiency of the treatment of CLL pts was following: 2 pts (33,3%) displayed disease progression(PD) in 2 and 4 weeks of A. monotherapy, 2 pts achived (33,3%) CR in 14 and 16 weeks, 2 pts (33,3%), achived PR, among them 1 patient showed PR after 5 FluCam courses, the other — after 14 weeks of A. monotherapy. At the completion of the study 4 pts (66,6%) had no evidence of MRD by flow cytometry(<0,01%).

Obtained results showed high effectiveness of A. and acceptable toxity, among resistant to F. CLL pts (66,6% responded), the majoority of them had unfavourable del 17p.

No relevant conflicts of interest to declare.