ABSTRACT
Introduction: Voxelotor is a first-in- class sickle haemoglobin polymerisation inhibitor that targets the pathophysiology of sickle cell disease (SCD). Studies have shown that voxelotor increases haemoglobin and reduces markers of haemolysis. Emerging evidence suggests that voxelotor may improve the clinical symptoms of SCD, lower vaso-occlusive crisis (VOC) rates, and reduce transfusion needs. Objective(s): To examine the real-world impact of voxelotor on transfusion, VOC, and hospitalisation rates among patients with SCD. Method(s): Medical and pharmacy claims data for patients >=4 years with SCD who started voxelotor between November 2019 and March 2022 were obtained from the Symphony Health database. Patients with >=1 year of data before the index date (date of first voxelotor claim) were included. Annualised study outcomes were calculated for patients with >=1 occurrence of the corresponding event in the 3-month preindex period. Outcomes from a 90-day lookback were reported for the total and paediatric (aged 4 to <18 years) populations. Result(s): Of 4023 eligible patients from the Symphony Health database included in the analysis, 596 were <18 years. Compared with the 3-month preindex period, significantly lower annualised rates of transfusions, VOCs, and hospitalizations, and lower annualised mean number of inpatient days, were observed in the total population and paediatric subgroup over the 3-month postindex period. For the total population, the annualised event rates declined by 50.6% for transfusions (n = 248), 23.1% for VOCs (n = 1368), 35.5% for VOC-related hospitalizations (n = 757), and 39.4% for all-cause hospitalizations (n = 928). The annualised mean number of inpatient days declined by 29.6% for VOC-related hospitalizations (n = 757) and by 22.9% for all-cause hospitalizations (n = 928). For paediatric patients, the annualised event rates declined by 79.6% for transfusions (n = 18), 42.4% for VOCs (n = 157), 56.8% for VOC-related hospitalizations (n = 81), and 51.5% for all-cause hospitalizations (n = 106). The annualised mean number of inpatient days declined by 54.1% for VOC-related hospitalizations (n = 81) and by 45.8% for all-cause hospitalizations (n = 106). Conclusion(s): Treatment with voxelotor may provide a clinical benefit to patients with SCD by reducing the frequencies of transfusions, VOCs, and hospitalizations and decreasing inpatient days. Greater reductions were observed in the paediatric subgroup, potentially due to the smaller sample size, historically greater treatment compliance in paediatric patients, or younger patients having accumulated fewer SCD-related complications, enabling a greater clinical response. Limitations include the study's non-randomized design, reliance on claims data, and changes in healthcare use during the COVID-19 pandemic confounding the data.