PS1505 CLINICAL AND ECONOMIC BURDEN OF MYELOFIBROSIS IN A LARGE US MANAGED CARE POPULATION
Authors: T. Burton, K. Parikh, M. Patel, K. Sundquist, L. Lal, R. Copher, A. Gerds
Journal: HemaSphere (2019)

Background: Myelofibrosis (MF) is a rare myeloproliferative neoplasm with hallmarks of bone marrow scarring, constitutional symptoms, and impaired hematopoiesis. MF may be de novo or secondary to essential thrombocythemia or polycythemia vera. Treatment options are limited and few patients undergo the only curative therapy, allogeneic hematopoietic cell transplantation (HCT). Consequently, the burden of MF is substantial due to its chronic nature as well as the impact on major organs (e.g., spleen and bone marrow) and the need for significant supportive care (e.g., chronic blood transfusions). Aims: To describe the clinical characteristics, health care resource utilization (HCRU), and costs associated with treating patients with MF in a large US managed care population. Methods: This retrospective analysis used administrative claims from a large US health plan to identify patients with MF from January 1, 2012 to June 30, 2018 (identification period). Adults (≥ 18 years) were included in the analysis if they had ≥ 2 non‐diagnostic medical claims ≥ 30 days apart, with primary MF ([International Classification of Diseases, 9/10th Revision] ICD‐9/10: 238.76, D47.4) or secondary MF (ICD‐9/10: 289.83, D75.81) diagnosis codes in any position during the identification period. Index date was defined as the date of the first MF claim during the identification period. Selected patients were continuously enrolled in a commercial or Medicare Advantage health plan for 12 months before the index date (pre‐index period) and 6 months after the index date (post‐index period). Clinical characteristics were assessed during the 12‐month pre‐index period; HCRU and costs were assessed during 6‐month pre‐index and post‐index periods. Health care costs included all health plan‐ and patient‐paid amounts adjusted to 2018 US dollars using the medical component of the consumer price index (CPI). All variables were analyzed descriptively. Results: Among the 1,191 patients identified, the median age was 72 years; 646 (54%) were male; 291 (24%) had a primary MF diagnosis code, and 46 (4%) had evidence of undergoing HCT during the study period. The median 12‐month pre‐index Charlson Comorbidity Index score was 2, and 155 (13%) had a score ≥ 5. The top 5 comorbidities during the 12‐month pre‐index period were: anemia (846 [71%]), hypertension (788 [66%]), heart disease (679 [57%]), dyslipidemia (664 [56%]), and urinary tract disease (619 [52%]). During the 6‐month pre‐index period, 405 (34%) patients had ≥ 1 emergency room (ER) visit and 262 (22%) had ≥ 1 inpatient hospitalization with a median length of stay of 7 days. During the 6‐month post‐index period, 442 (37%) patients had ≥ 1 ER visit and 361 (30%) had ≥ 1 inpatient hospitalization with a median length of stay of 11 days. Nearly 90% of patients had ≥ 1 outpatient pharmacy fill during the 6‐month pre‐index (1,035 [87%]) and post‐index (1,062 [89%]) periods. Total median costs were USD 8,834 and USD 16,716 during the 6‐month pre‐index and post‐index periods, respectively. Inpatient hospitalizations accounted for roughly a third of the total average costs during the same time periods. Summary/Conclusion: Patients with MF have a considerable disease burden coupled with high HCRU and costs. This is influenced, in part, by a high degree of comorbid conditions and a limited number of effective therapies. Better treatment options may reduce the hospitalizations and outpatient visits that are major drivers of costs.