Real-world treatment patterns and health care resource use for patients with myelofibrosis: results from the METER study

Myelofibrosis (MF), a myeloproliferative neoplasm, was most commonly treated with hydroxyurea (HU) before approval of ruxolitinib (RUX), now the standard of care. Factors that influence real-world MF treatment patterns are not well understood. The METER study was a multi-country, retrospective chart review of MF treatment patterns, treatment effectiveness, and health care resource utilization. Of 997 eligible patients, 65.9% had primary MF, and 11.7% were transfusion dependent. Median time from diagnosis to the start of initial treatment (index date) was 29 days (interquartile range [IQR], 1-140). RUX was the most common first-line (1L) therapy (49.0%), followed by HU (40.2%); 48.5% of patients remained on 1L therapy through week 156. Seventy-seven patients underwent allogeneic stem cell transplantation; transplantation was uncommon at 1L, increasing from 2.2% at week 24 to 11.0% at week 156 in patients ≤70 years of age. Median overall survival was 79.1 months (95% confidence interval [95% CI], 70.8 to not estimable [NE]) in all patients, 142.3 months (95% CI, 74.1 to NE) for non-RUX patients, 77.6 months (95% CI, 64.2-85.9) for patients on RUX 1L therapy, and 72.6 months (95% CI, 62.0 to NE) for RUX 2L+ patients. Of patients who experienced ≥1 corresponding event, the median hospital length of stay (LoS; n = 520), intensive care unit LoS (n = 71), and number of transfusions (n = 375) were 16 days (IQR, 7-37), 5 days (IQR, 2-13), and 12 (IQR, 4-26), respectively. Despite improvements, there were numerous hospitalization and transfusion events among these patients in routine practice. This trial was registered at www.ClinicalTrials.gov as #NCT05444972.