[Cytogenetic response as a marker of efficacy of chronic myeloid leukemia therapy with a BCR-ABL thyrosine kinase inhibitor glivek].

Aim: Clinical practice with the drug glivek (imatinibe mesilate, ST1571) blocking activity of oncoprotein p210 shows that a cytogenetic response can be reached in 50-60% of patients with chronic myeloid leukemia (CML), in a late chronic phase (CP) in resistance to or intolerance of interferon alpha (IF-alpha) and in 24-43% of patients in the acceleration phase (AP). This study aimed at assessment of the rate and stability of a cytogenetic response (CR) and long-term results of survival in CML patients on glivek.
Material and Methods: Glivek was given to 195 CML patients (median of the treatment duration was 42 months, 1-156 months, of the patients' age--46 years). 79 patients were in CP, 116--in AP. The doses were 400 mg/day and 116 mg/day, respectively. Karyotype was studied before the treatment and later after each 6 months.
Results: A considerable CR was achieved in 57% patients in CP and 44%--in AP. Of them complete CR was obtained in 48 and 35%, respectively. Marked CR is a favourable prognostic factor. Survival of patients with marked CR in CP (97% 0 and AP (89%) was significantly higher than without CR (58 and 47%, respectively, p < 0.05). Marked CR persisted in 95% cases in both phases of CML. In complete CR, a repeated study of karyotype revealed residual number of Ph+ cells both in CP and AP in 86% patients. This demonstrates necessity to take glivek continuously in achievement of a complete CR by karyotypic test. Glivek inhibits the disease progression, lowers annual lethality. 42-month (median of glivek treatment duration) overall survival reached 91 and 59% in CP and AP, respectively.
Conclusion: CR is an integral index prognosticating CML course. Survival rose significantly in patients with marked CR both in CP and AP of CML. Marked CR is persistent in continuous glivek therapy. The rate of a CR depends much on the disease stage.