Comparison of Costs and Health Care Resource Utilization (HRU) in Chronic Lymphocytic Leukemia (CLL) Patients Treated with Front-Line Ibrutinib or Chemoimmunotherapy

BACKGROUND

Most CLL patients in the US are treated in the front-line with either Ibrutinib or chemotherapy-backbone regimens (chemo), including chemoimmunotherapy (CIT). While treatment selection is based on risk stratification, comorbidities, patient choice, and physician preference, the comprehensive economic impact of selecting ibrutinib versus chemo/CIT is not well-studied and generally not known. We aimed to compare real-world HRU of ibrutinib versus chemo/CIT-treated CLL patients receiving therapy in the first line setting.

PATIENTS and METHODS

Newly diagnosed CLL patients initiating therapy between 01/01/2014-09/30/2016 were selected from the Inovalon Medical Outcomes Research for Effectiveness and Economics (MORE²) Registry payer claims and remittance dataset. Patients receiving ibrutinib or chemo/CIT regimens for the treatment of CLL were compared across HRU from the start of their first cycle of therapy to the end of their first cycle of therapy. HRU was reported as per-patient per-month (PPPM) to mitigate the effects of different follow-up times. HRU were reported as inpatient, emergency room (ER), office visit (physician office) or other outpatient ambulatory visits (outpatient). Time to initiation was assessed from CLL diagnosis to the start of the patients first cycle of therapy. P-values were generated using chi-square tests for categorical variables and Wilcoxon test for means, as utilization and cost outcomes are often non-normally distributed.

RESULTS

A total of 1,086 patients were identified [178 (16.4%) on ibrutinib and 908 (83.6% on chemo/CIT). The top 5 chemo drugs used and dispensed were rituximab, bendamustine, cyclophosphamide, fludarabine, and vincristine either alone or in combinations. No statistical differences were found between ibrutinib versus chemo/CIT patients in median age (65 years for both), gender distribution (64% males), or geographic locations within the US. Ibrutinib-treated patients were more likely to have commercial insurance while chemo/CIT patients were more likely to have Medicaid [(41.6% vs. 34.2%) and (15.3% vs. 9.6%) respectively; p=0.046]. Mean costs per inpatient hospital stay per month were higher in the chemo/CIT patients versus ibrutinib ($1981 vs. 1480; p=0.004). While there was no statistical difference in emergency room (ER) visits between both cohorts, costs of ER visits per month were higher in the chemo/CIT patients ($317 vs. 152; p=0.0002). Office visits per month were more frequent in chemo/CIT patients (5.7 visits vs. 1.8; p<0.0001) as well as mean costs per month ($1365 vs. $744; p<0.0001). More frequent outpatient visits per month were observed in chemo/CIT patients versus ibrutinib-treated (mean 7.71 vs. 3.6; p<0.0001) translating into higher mean costs ($3613 vs. 2326; p=0.014). Time to the initiation of the first cycle of therapy was longer in ibrutinib vs chemo/CIT patients (167.1 vs 92.24, p= <.0001).

CONCLUSIONS

When used in first cycle therapy for CLL, rates of resource utilization and total costs of care were significantly lower compared to chemo/IT.. Ibrutinib-treated patients have lower ER and inpatient costs per month and less frequent office and outpatient visits than chemo/CIT-treated patients. Longer follow up is needed to better understand the economic impact on patient outcomes.