Publication Date:
2014-12-06
Description:
Background: Second generation tyrosine kinase inhibitors (2G-TKIs) are more potent than imatinib against chronic myeloid leukemia in chronic phase (CML-CP) as a first-line therapy, and the majority of patients (pts) on 2G-TKIs could achieve favorable molecular responces over MR3.0 by 24 M (Saglio G, et al. Blood 2011, Kantarjian HM, et al. Blood 2012). It is also likey that molecular response at 3 M will predict outcome for CML-CP pts on imatinib. Furthermore, Mustjoki S, et al. showed that Ph+ stem cell burden at diagnosis is a prognostic marker of molecular responses at 3-9 M on dasatinib or imatinib (Leukemia 2013). Thus, early prognostic marker of outcome is feasible for CML-CP on TKIs. Methods: We are conducting a phase II study (N-road) for newly diagnosed CML-CP pts, in which nilotinib 300mg BID is given for 24 M and is to be escalated to 400mg BID if no optimal response at any check points. The primary endpoint is CMR rate by 24 M, and secondary endpoints include MR3.0/MR4.0 by 12 M and exploring prognostic factors. In this setting, the impact of initial Ph+ stem cell burden on clinical findings and therapeutic responses has been investigated in a sub-study. By July 2014, 48 pts were enrolled and BM CD34+ cell fractions could be evaluated by FACS-FISH analysis at diagnosis in 43 pts, among those 35 pts passed 3 M, 34 pts 6 M and 15 pts 12 M, respectively. Results: MR3.0 rate was 8/35 at 3M, 23/34 at 6M and 10/15 at 12M. When 43 pts were classified into two groups (higher: H, lower: L) according to the mean CD34+ cell counts at diagnosis (5995/mL of BM aspirates), there were significant differences (p
Print ISSN:
0006-4971
Electronic ISSN:
1528-0020
Topics:
Biology
,
Medicine
Permalink