Early Molecular Response to Imatinib First-Line Therapy and Predictive Factors of Poor Outcomes for Chronic Myeloid Leukemia Patients in Côte d'Ivoire.

The present study aimed to evaluate for the first time, the early molecular response (EMR) to imatinib at 3 months for patients with chronic myeloid leukemia and to determine the predictive factors that influence poor outcome and response. 60 newly diagnosed CML patients were enrolled from May 2018 to June 2023. They received imatinib and prospectively underwent a molecular evaluation. Their EMR was assessed using a RT-qPCR method and expressed as the IS transcript level at 3 months. Potential factors impacting the EMR were identified using the Cox proportional hazard regression models. The effects of an EMR on the cumulative incidence of a deep molecular response (DMR) were also evaluated. Out of the 60 CML patients recruited, 29 (48%) achieved an optimal response with TKI therapy after 3 months. The cumulative rate of molecular response was 16 (36%) for a major molecular response (MMR), 10 (23%) for MR4, 8 (18%) for MR4.5, and 6 (14%) for MR5, while 4 (9%) showed indetectable transcript. In addition, as 26 (90%) of patients with optimal response at 3 months showed a DMR, we determined that an optimal response to TKI at 3 months was significantly correlated with a DMR. We also identified through multivariate analysis that seven independent risk factors significantly influenced an EMR to TKI. These factors included male, late diagnosis, advanced performance status, the presence of splenomegaly, high-ELTS risk groups, a domain mutation, and complete hematologic response after more than 30 days. Our study demonstrates that an EMR at 3 months has a predictive value for a DMR. In addition, a MMR and a DMR can be predicted using a combination of parameters that either have a significant impact on the optimal response, or that can serve as prognostic indicators for molecular response, especially in low-income countries, where molecular assessment and monitoring are not available or possible.