Healthcare Resource Utilization and Costs in Patients with AML Treated with Post-Transplant Maintenance Therapy

Abstract

AbstractHealthcare Resource Utilization and Costs in Patients with AML Treated with Post-Transplant Maintenance Therapy Rachel Kneitel Chair of the Supervisory Committee: Noemi Kreif Pharmacy Background: Allogeneic hematopoietic cell transplantation (allo-HCT) has improved survival in patients with acute myeloid leukemia (AML); however, post-transplant relapse remains the most common cause of treatment failure and death. There is limited data regarding the economic and clinical burden associated with the progression from diagnosis to post-transplant maintenance therapy, which is intended to maintain remission in patients. Objective: To describe healthcare resource utilization (HRU) and quantify costs among commercially insured, Medicaid, and Medicare beneficiaries who have and have not received maintenance therapy after allo-HCT. Methods: We conducted a retrospective cohort study on commercially insured, Medicare, and Medicaid beneficiaries with AML who were and were not prescribed maintenance therapy following allo-HCT between October 1st, 2015 and March 31st, 2024 using claims from the Merative MarketScan® database. The final analytic cohort included 373 patients, of whom 43 were prescribed maintenance therapy following allo-HCT. To account for observed differences between those who received maintenance therapy and those who only received allo-HCT, we employed inverse probability weighting (IPTW) using propensity scores estimated from baseline characteristics. We assessed differences in all-cause monthly HRU by summarizing the number of emergency department (ED), inpatient (IP), outpatient (OP) visits, and hospital length of stay throughout the 12 month follow up period. We also evaluated monthly supportive therapy utilization patterns, including therapies that stimulate neutrophil production to reduce infection risk and promote red blood cell production to manage anemia, to assess treatment-related care requirements. Poisson regression models were used to estimate monthly event rates for each HRU category. Total healthcare costs were reported as the sum of ER, IP, OP, and outpatient pharmacy costs to provide insights into the costs associated with maintenance therapy. Transfusion burden was evaluated by counting the number of transfusions for each cohort. Results: The maintenance therapy group demonstrated significantly higher HRU across multiple service types. Office visits were more than doubled (IRR = 2.11, p < 0.001), with significant increases in IP visit rates (IRR = 1.39, p = 0.015), hospitalization rates (IRR = 1.37, p = 0.024), and overall OP utilization (IRR = 1.79, p < 0.0001). Specialist clinic and ED visit rates were higher but not statistically significant (IRR = 1.5, p = 0.151; IRR = 1.75, p = 0.309), respectively. Supportive therapy utilization peaked within the first three months post-transplant in the maintenance therapy group before converging with controls by month eight. Healthcare costs were driven primarily by IP expenses, with the maintenance therapy group incurring substantially higher costs four to ten months after allo-HCT. Pharmacy costs were expectedly higher in the maintenance therapy group throughout follow-up. Blood transfusion requirements were minimal in both groups, with 93% of maintenance therapy patients and 97.6% of allo-HCT only patients requiring no transfusions during the 12-month follow-up period. The mean monthly length of stay was significantly longer in the allo-HCT only group compared to the maintenance therapy group (33.77 ± 31.49 days vs. 20.97 ± 15.36 days), with a mean difference of 12.72 days (95% CI: 11.14,14.31; p = 0.001). Discussion: Our findings show that those who received maintenance therapy following allo-HCT were associated with having significantly greater healthcare resource utilization and costs, as shown by higher rates of office visits and hospitalizations. IP visits accounted for the largest share of monthly healthcare expenditures, with the maintenance group incurring notably higher IP costs from months four to ten after allo-HCT. Pharmacy costs were the second largest component and were consistently higher in the maintenance group. Supportive therapy use was substantially higher in the maintenance group during the early post-transplant period, peaking within the initial three months. These findings highlight the need to balance the clinical benefits of maintenance therapy with its increased demands on healthcare resources.