2026 Eastern States Conference

Authors: Madhura Pradhan, PharmD; Nadirah El Amin, DO; Jennifer Newlin, PA-C; Cady Noda, PharmD, BCPPS 

Objective: At the conclusion of my presentation, the participants will be able to explain the clinical benefit and safety of hydroxyurea in patients with hemoglobin SC disease of all ages.  

Self-Assessment Question: True or False: Primary literature and this current project recommend restricting the use of hydroxyurea to patients with HbSC aged 18 years and older due to higher rates of neutropenia in patients less than 18 years of age. Answer: False 

Background: Current sickle cell disease (SCD) guidelines offer vague recommendations for hydroxyurea (HU) use in patients with hemoglobin SC disease (HbSC). We aim to characterize HU use in patients with HbSC of all ages at a large academic medical center. 

Methods: This quality improvement project is a retrospective chart review of pediatric and adult patients diagnosed with HbSC who were prescribed hydroxyurea. Primary outcome was vaso-occlusive crisis (VOC) and acute chest syndrome (ACS), stratified and compared via proportion of days covered (PDC) status: low PDC vs moderate PDC vs high PDC. Secondary outcomes include average HbF, average total Hgb, hospitalization for any reason, incidence of neutropenia or thrombocytopenia, and incidence of hydroxyurea discontinued by the patient or medical team, all within the last 12 months. Data was analyzed via descriptive statistics for continuous data and Fisher’s Exact Test for nominal data. 

Results: There were 109 patients who had a diagnosis of HbSC and prescribed HU. More patients fell in the low PDC group (63.3%) vs moderate PDC (8.26%) vs high PDC (28.44%) groups. Median number of VOC was 1 event [IQR 0 – 6] in the low PDC group, and 1 event [IQR 0-4.75] in the moderate-to-high PDC groups (p=0.987). Median number of ACS events was 0 in both the low PDC and moderate-to-high PDC groups (p=0.117). There was no difference in incidence of neutropenia (p=0.636), thrombocytopenia (p=1.0), HU stopped by the team (p=0.296), or HU stopped by the patient (p=0.737) within the last 12 months in the low PDC and moderate-to-high PDC groups.  

Conclusions: Patients with HbSC demonstrated low adherence to hydroxyurea based on PDC measurements. Rates of VOC events were similar between the low PDC and moderate-to-high PDC groups. The low incidence of thrombocytopenia and neutropenia supports the safety of HU in this population. These findings highlight the need to improve medication adherence while continuing to offer HU to patients with HbSC at our institution.