Discontinuation of Ruxolitinib May Worsen Outcomes for Patients With Myelofibrosis

Patients with myelofibrosis who are taking ruxolitinib (Jakafi) may experience an increased morbidity burden and additional risk factors if they discontinue the treatment, according to a new study published in Journal of Medical Economics.

Outcomes among patients with primary myelofibrosis or secondary myelofibrosis have not been well studied using real-world data sources, according to the authors. The investigators analyzed data from the Truven Health Analytics MarketScan and the Optum integrated virtual electronic health records and claims databases on patients who received a myelofibrosis diagnosis between 2006 and 2015, and data from the Surveillance, Epidemiology, and End Results (SEER)-Medicare linked database on patients with a myelofibrosis diagnosis between 2007 and 2014.

“Despite significant improvements in disease-related symptoms and quality of life, over half of the patients discontinue ruxolitinib treatment within 2-3 years due to adverse events or loss of treatment response,” the authors explained.

A total of 290 patients across the 3 databases were included in the analysis. They were followed from the date of ruxolitinib discontinuation until either death or the end of the follow-up, which was December 31, 2014.

The median age of patients at the time of ruxolitinib discontinuation was 68.0 (range, 62.0-77.0) years. Patients in the <45-64 year age group were the largest proportion (39%) studied. The median time from ruxolitinib initiation to discontinuation was 284 (range, 113.0-562.0) days. After discontinuing ruxolitinib, 83.1% of patients did not receive any supportive care treatment, while some received hydroxyurea (4.5%), recombinant erythropoietin (2.4%), or chemotherapy (0.3%).

Although morbidities had increased from the 30-day period right after patients started ruxolitinib to the 30-day period right before they discontinued the treatment, those morbidities further increased following discontinuation. For example, 36% of patients had anemia following initiation, 45% right before discontinuation, and 53% in the 30 days after discontinuation. There were similar increases for thrombocytopenia and neutropenia.

The median overall survival after ruxolitinib discontinuation was 11.1 (range, 8.4-14.5) months. Age (>65 years), gender (female), and Charlson Comorbidity Index score were all associated with increased hazard of treatment progression/death.

The authors recommend additional research to assess survival over a longer period of time as well as potential prognostic variables that affect survival.

“With limited treatment options being available in the real-world post ruxolitinib use, our study findings underscore the need for more treatment options to manage MF after ruxolitinib is discontinued,” the authors concluded.

Reference

Mascarenhas J, Mehra M, He J, Potluri R, Loefgren C. Patient characteristics and outcomes after ruxolitinib discontinuation in patients with myelofibrosis. J Med Econ. Published online March 31, 2020. doi:10.1080/13696998.2020.1741381