Recent Patterns of Care with BTK Inhibitors and Distribution of Social Determinants of Health Among Patients with CLL/SLL in the US Community Setting

BACKGROUND: The treatment landscape for patients with chronic lymphocytic leukemia or small lymphocytic lymphoma (CLL/SLL) has shifted with the introduction of second-generation Bruton tyrosine kinase (BTK) inhibitors. Few real-world studies, however, have examined sequencing patterns among BTK inhibitors for CLL/SLL and the patient characteristics across different sequences, including social determinants of health (SDOH). The aim of this study is to examine the characteristics, treatment patterns, and SDOH among patients with CLL/SLL who received BTK inhibitors in a large network of community oncology practices. METHODS: This was a retrospective study of adult patients diagnosed with CLL/SLL who were prescribed a BTK inhibitor between 1/1/2020-4/30/2023 in The US Oncology Network. Study data were captured from structured fields in the iKnowMed electronic health record (EHR), with linkage to external sources to evaluate patients' Area Deprivation Index (ADI) scores and rural/urban status. ADI scores were determined by mapping patients' home addresses to a census block group (CBG), which was then linked to the ADI. ADI rankings are based on CBG and determined by the domains of income, education, employment, and housing quality, where high scores indicate increased disadvantage. Low socioeconomic status (SES) was defined as the top 20% of ADI scores on a national and state level (cut-off based on literature review). Rural/urban status was based on the RUCA codes published by the US Department of Agriculture. Insurance coverage was reported “as is” in the claims system with Medicaid an indicator of low SES. Results were assessed by treatment sequence, and SDOH measures results were reported as counts, frequency, and 95% confidence intervals (CI). Chi Square p-values were reported for selected SDOH measures and are shown in text. Data are presented for treatment subgroups with at least 30 eligible patients. RESULTS: In total, 2,082 patients were included in the analysis (median age 73 years; 61.9% male; 73.5% white; 35.0% Rai stage 0-I; median follow-up 14.1 months). The highest proportion of patients received acalabrutinib or ibrutinib without an observed subsequent BTK inhibitor (n=1,159 and n=628, respectively). Patient characteristics by the top 6 treatment sequences are provided in Table 1. Demographic and clinical characteristics across the treatment sequences were similar, including sex, race, and ethnicity distributions, along with Rai stage and ECOG p