Evaluation of the effect of voxelotor and darbepoetin alfa on hemoglobin levels in patients with sickle cell disease.

Background: To date, there is limited evidence on patients utilizing both voxelotor and darbepoetin alfa and its impact on hemoglobin levels. The objective is to evaluate the effect of voxelotor and darbepoetin alfa on hemoglobin levels in patients with SCD.

Research design and methods: This was a retrospective chart review study that assessed the primary independent variable as the utilization of either voxelotor alone, darbepoetin alfa alone, or the concurrent administration of voxelotor and darbepoetin alfa. Descriptive statistics were utilized to obtain the mean standard deviation for numerical variables and proportions for categorical variables.

Results: A total of 23 participants were included in this study. When comparing baseline to 2 months and 3 months, participants on voxelotor alone experienced a 3% decrease and a 6.6% increase in hemoglobin, darbepoetin alfa alone group a 4.3% decrease and a 0.6% increase in hemoglobin and voxelotor and darbepoetin group a 4.4% decrease and a 0.5% decrease in hemoglobin levels. Fifty percent of the participants in the voxelotor group and 6 (66.7%) participants in the voxelotor plus darbepoetin alfa group experienced adverse drug events.

Conclusions: Voxelotor resulted in a clinically significant difference in the percent change of hemoglobin from baseline to 3 months.