Real-World Experience with Ruxolitinib in Myeloproliferative Neoplasms: A Single-Center Study from Oman

Abstract

Background: Myeloproliferative neoplasms (MPNs)—including primary myelofibrosis (PMF), polycythemia vera (PV), and essential thrombocythemia (ET)—are clonal stem-cell disorders driven by JAK–STAT pathway activation within an inflammatory microenvironment. Ruxolitinib (RUX), a JAK1/2 inhibitor, improves splenomegaly and symptom burden in myelofibrosis and serves as second-line therapy in hydroxyurea-resistant/intolerant PV. However, real-world data from Middle Eastern populations remains scarce. This study evaluates the effectiveness, safety, and dosing practices of RUX in a heterogeneous Omani MPN cohort. Methods: Electronic records were reviewed for adults diagnosed with MF, PV, or ET who received RUX at Sultan Qaboos University Hospital or the National Hematology and BMT Center between 2018 and 2025. Only patients with at least six months of follow-up were included. Clinical variables, laboratory results, dosing information, and data on treatment responses and toxicities were extracted. Outcomes focused on spleen size changes, symptom improvement, hematologic responses, adverse events, and reasons for treatment discontinuation. Results: Twenty-eight patients were included (71% PMF; mean age 52.6 years). The median time from diagnosis to RUX initiation was 28 months. Among MF patients, mean spleen size decreased by 35% (p = 0.003); 28% achieved ≥35% reduction. Symptomatic improvement was reported by 60%. LDH levels remained unchanged. PV patients showed spleen control in 75% and symptom benefit in all cases, while ET responses were limited. Cytopenias (21%) and infections (11%) were the most common toxicities; discontinuation occurred in 8/28 of patients, and two patients died while on therapy. Initial dosing was frequently inappropriate, particularly underdosing in MF and overdosing in PV. Conclusions: RUX provided meaningful spleen and symptom improvement in MF and PV; however, toxicity, delayed initiation, and inconsistent dosing practices limited overall outcomes. Enhanced guideline-based dosing, proactive toxicity management, and structured multidisciplinary follow-up are essential to optimize RUX use in regional MPN practice.

Keywords