Real-World Analysis of Ruxolitinib Treatment Patterns and Outcomes Among Patients with Myelofibrosis

Background: Myelofibrosis (MF) is a myeloproliferative neoplasm characterized by bone marrow fibrosis, splenomegaly, cytopenias, and poor survival. Ruxolitinib (RUX) is the only approved treatment for Intermediate or High-risk MF. In a previous study, we have shown almost 1 in 3 patients initiating RUX had dose modifications during the first 3 months of treatment (Burton T et al. HemaSphere 2019). The objective of this study was to assess RUX treatment patterns among patients with MF. Methods: This retrospective analysis used administrative claims data from a large US health plan to identify adults (aged ≥ 18 years) with ≥ 1 claim for RUX and ≥ 2 non-diagnostic medical claims for primary (International Classification of Diseases [ICD] 9th or 10th Revision [9/10]: 238.76, D47.4) or secondary MF (ICD-9/10: 289.83, D75.81) from January 1, 2012 to June 30, 2018. The first RUX claim on or after the first MF claim defined the index date. Included patients were continuously enrolled in a commercial or Medicare Advantage health plan for 3 months before the index date (pre-index period) and 6 months on or after the index date (post-index period). Clinical characteristics, MF-related treatments, health care resource utilization (HCRU), and costs were assessed during the pre- and post-index periods. Costs were adjusted to 2018 US dollars using the medical component of the Consumer Price Index. Cohorts were created based on the maximum (max) RUX daily dose observed during the 6-month post-index period: suboptimal max Results: Among 495 eligible patients, mean (SD) age was 69.4 (10.3) years; 54.1% were male; and 25% had a primary MF diagnosis code. Median initial RUX dose was 30 mg/day and patients continued with this dose for a mean (SD) of 70.0 (45.8) days. RUX dose was modified for 19.4% of patients during the 6-month post-index period, and the distribution of max RUX daily doses was: 40 mg (5.7%). Two groups based on max RUX dosing were further analyzed: 191 (38.6%) in the SUB cohort ( Conclusion: In this study, patients with MF treated with RUX experienced significant disease burden and high costs, regardless of dose. Both anemia and thrombocytopenia were observed along with nearly half of patients using a supportive agent. Given the large proportion of patients with a dose adjustment, suboptimal dosing, and an IP hospitalization, there continues to be a need for additional therapeutic options for patients with MF. Disclosures Parikh: Celgene Corporation: Employment, Equity Ownership. Patel: Celgene Corporation: Employment, Equity Ownership. Sundquist: Optum: Employment, Equity Ownership. Lal: Optum: Employment. Copher: Celgene Corporation: Employment. Gerds: Roche: Research Funding; Incyte: Consultancy, Research Funding; Sierra Oncology: Research Funding; CTI Biopharma: Consultancy, Research Funding; Imago Biosciences: Research Funding; Celgene Corporation: Consultancy, Research Funding; Pfizer: Consultancy.