Imatinib mesylate therapy of chronic phase chronic myeloid leukemia resistant or intolerant to interferon: results and prognostic factors for response and progression-free survival in 150 patients.

BACKGROUND AND OBJECTIVES: Imatinib mesylate has recently been shown to be highly effective in chronic-phase chronic myeloid leukemia (CML). The results of imatinib treatment in chronic-phase CML patients resistant or intolerant to interferon (IFN) and the factors predicting therapeutic response and progression-free survival were analyzed. DESIGN AND METHODS: One hundred and fifty patients with chronic-phase CML resistant (n=111) or intolerant (n=39) to IFN were treated with imatinib. Prognostic factors for response and disease progression were assessed by multivariate analysis. RESULTS: The median time from diagnosis was 43 months (0.5-188), median IFN therapy 21.5 months (0.5-140) and median follow-up from starting imatinib 13.6 months (range: 3-23). Complete hematologic response was achieved in 96 of 97 patients. Complete, partial and minor cytogenetic responses were present in 44%, 22%, and 8% of patients at 12 months. Grade III-IV neutropenia, thrombocytopenia, and anemia developed in 33%, 16%, and 6% of patients, respectively. Sixty-five patients discontinued treatment for a median of 4 weeks (1-36) due to toxicity. The rate of progression-free survival (lack of accelerated/blastic phase with persistent response) was 89.2% (95% CI: 84-94.4) at 12 months and 80.2% (95% CI: 72.2-88.2) at 18 months. Platelets > 450x10(9)/L and treatment discontinuation > 4 weeks were associated with a lower rate of major (complete plus partial) cytogenetic response. Patients in Sokal's high-risk group and those who did not achieve a major cytogenetic response had significantly shorter progression-free survival. INTERPRETATION AND CONCLUSIONS: Imatinib is highly effective in chronic-phase CML patients resistant or intolerant to IFN, especially in those with normal platelet counts and in those not requiring prolonged treatment discontinuation due to neutropenia.

Imatinib mesylate (STI571) treatment in patients with chronic-phase chronic myelogenous leukaemia previously submitted to autologous stem cell transplantation.

Imatinib mesylate (STI571) is a highly effective and well-tolerated treatment for patients with chronic-phase chronic myeloid leukaemia (CML), but information on its efficacy and tolerance in intensively pretreated patients is scarce. Thirty-three chronic-phase CML patients who were resistant or intolerant to interferon (IFN) and had been previously submitted to autologous stem cell transplantation were treated with imatinib for a median of 14 months (range: 6-19 months). Seven patients were in haematological response (HR) at the start of treatment; the remaining 26 attained a HR at a median of 3 weeks (range: 1-4 weeks). Major cytogenetic response rates at 3, 6 and 12 months were 42%, 45% and 55%, respectively, including 21%, 24% and 33% complete responses. Grade 3-4 neutropenia, thrombocytopenia and anaemia developed in 33%, 27% and 12% of patients respectively. Non-haematological toxicity included superficial oedema (21% of patients), gastrointestinal symptoms (18%), muscle cramps (15%), skin rash and liver enzyme increase (3% each). These results were not significantly different from those in 65 chronic-phase CML patients, resistant or intolerant to interferon without a previous ASCT, who were included in the same protocol. Imatinib mesylate is effective and safe in chronic-phase CML patients with a previous history of intensive treatment.

Risk factors for acute graft-versus-host disease in patients undergoing transplantation with CD34+ selected blood cells from HLA-identical siblings.

A study on 315 patients undergoing transplantation with CD34+ selected blood cells from HLA-identical siblings was performed to determine risk factors for acute GVHD (aGVHD). Recipients of a dose of CD34+ cells (x 10(6)/kg) of 2 or less, more than 2 to 4, and more than 4 had a cumulative incidence of aGVHD grades I-IV of 21%, 35%, and 43%, respectively (log-rank P =.01); similarly, recipients of a dose of CD3+ cells (x 10(6)/kg) of 0.05 or less, more than 0.05 to 0.1, and more than 0.1 had a cumulative incidence of aGVHD grades I-IV of 18%, 35%, and 44%, respectively (log-rank P =.007). Using a Cox regression model, 4 independent factors for aGVHD I-IV were identified: increased CD34+ cell dose (P =.02), increased CD3+ cell dose (P =.02), female patients (P =.01), and higher patient age (> 42 years) (P =.007). This study shows, for the first time in T-cell-depleted transplantations, a positive correlation between the number of CD34+ cells and aGVHD and, also, that the number of CD3+ cells necessary to initiate aGVHD is lower than previously reported.