Safety and effectiveness of ruxolitinib in the real-world management of polycythemia vera patients: a collaborative retrospective study by pH-negative MPN latial group.

Ruxolitinib is approved for polycythemia vera (PV) patients after failure to previous cytoreductive therapy, based on durable results observed in phase 3 trials. We report a multicenter retrospective study demonstrating the efficacy and safety of ruxolitinib in real-life setting. Eighty-three patients were evaluated. Median follow-up was 24.5 months (IQR 14.0-29.3). At a 3-month response assessment, ruxolitinib provided significant benefit in reducing hematocrit (HCT) level (p < 0.001), phlebotomy requirement (p < 0.001), leucocytes (p = 0.044), and disease-related symptoms (p < 0.001). The exposure-adjusted rates (per 100 patient-years) of infectious complications, thromboembolic events, and secondary malignancies were 6.9, 3, and 3.7, respectively. Non-melanoma skin cancers (NMSC) were the most frequent (40%) SM type. Lymphoproliferative disorders were not detected. Five (6%) patients permanently discontinued ruxolitinib treatment and four (5%) evolved in myelofibrosis (MF), but none in acute leukemia. The rate of MF evolution per 100 patient-years of exposure was 2.8. In our experience, ruxolitinib confirmed its efficacy and safety outside of clinical trials.