Imatinib mesylate in early chronic phase chronic myeloid leukemia: Experience from a developing country.

There are few publications on responses of patients with chronic phase chronic myeloid leukemia (CP-CML) from the Indian sub continent to imatinib mesylate (IM). This study analyses the response rates, progression free survival (PFS), overall survival and adverse events of early CP-CML patients on IM. Analysis of patients with untreated early CP-CML on IM from 2003 to 2006 was done. Standard criteria for hematological and cytogenetic responses were used. There were 201 patients with a median follow-up of 29.5 months. Thirty three percentage, 40% and 27% belonged to the low, intermediate and high-risk Hasford groups, respectively. Ninety seven percentage achieved complete hematological response. Fifty six percentage achieved complete cytogenetic response (CCR), 23% partial cytogenetic response, 17% minor response and 4% no response. The estimated PFS and OS at 29 months for the whole group was 77 and 94%, respectively. Hasford risk groups were predictive of CCR (p = 0.0018). None required permanent drug discontinuations due to adverse events. This study shows sub optimal outcomes to IM in early CP-CML. Late presentation may be one of the reasons for these outcomes. IM was well tolerated.