Early Haematological Response and Short-Term Safety of Frontline Imatinib in Adults with Chronic Myeloid Leukaemia: A Retrospective Study in a Resource-Limited Setting

Abstract

Background: Imatinib mesylate is a tyrosine kinase inhibitor that has transformed the treatment of chronic myeloid leukaemia. However, information on its real-world use among sub-Saharan African populations remains limited. Aims: This study evaluated early haematological response and recorded adverse drug reactions among Sudanese adults receiving first-line imatinib for Philadelphia chromosome-positive chronic myeloid leukaemia. Methods: A single-centre retrospective cohort study was conducted using the medical records of 89 adults with Philadelphia chromosome-positive chronic myeloid leukaemia who were registered and treated at Khartoum Oncology Hospital in 2019. The hospital was the only authorised dispensing site for the Glivec® International Patient Assistance Program in Sudan during the study period. Patients in the chronic phase received imatinib at an initial dose of 400 mg/day, whereas those in the accelerated phase received 600 mg/day. Haematological parameters and recorded adverse drug reactions were assessed at baseline and after one and three months of treatment. Data were analysed using SPSS. Results: Of the 89 patients, 52.0% were male, and 37.1% were aged 31–40 years. At diagnosis, 95.5% had chronic-phase disease and 95.5% had splenomegaly. Complete haematological response was achieved by 79.8% of patients at one month and 94.4% at three months. Haematological adverse reactions were the most frequently recorded toxicities, including neutropenia in 20.2% and thrombocytopenia in 10.1%. Seven patients, representing 7.9% of the total cohort and 18.4% of those with recorded adverse drug reactions, permanently discontinued imatinib and transitioned to a second-generation tyrosine kinase inhibitor. Accelerated-phase disease was associated with a lower complete haematological response rate and a greater likelihood of an elevated white blood cell count at three months, although this finding was based on only four accelerated-phase patients. Age and sex were not significantly associated with response. Conclusion: A high proportion of patients achieved an early complete haematological response following cytoreductive bridging and initiation of imatinib. Interpretation is limited by preceding hydroxyurea exposure, retrospective ascertainment of adverse reactions, short follow-up, and the absence of routine molecular and cytogenetic monitoring. Improved access to standardised molecular testing would strengthen treatment-response assessment and long-term CML care in resource-limited settings.