Clinical Outcomes of Ruxolitinib Treatment in Patients With IPSS Intermediate-1-Risk Myelofibrosis: Interim Analysis From an Italian, Prospective Study (ROMEI)

Ruxolitinib (RUX), a JAK1/2 inhibitor, demonstrated treatment benefits for myelofibrosis (MF) in intermediate-1 (Int-1)–risk patients with a significant disease burden; however, the evidence is scarce. This interim analysis investigated the efficacy and safety of ruxolitinib in patients with Int-1-risk MF. ROMEI, a multicenter, observational, prospective study, enrolled 508 adult patients with MF receiving ruxolitinib according to approved indications. The present interim analysis was focused on 107 eligible patients in the Int-1-risk group. Primary endpoints included changes in symptoms response and health-related quality of life scores. Secondary endpoints included spleen response evaluation, overall survival, and safety including dosing pattern and dose interruptions. Among the 107 Int-1-risk patients with a median age of 63 years, 65.5% were highly symptomatic (total symptoms score: ≥ 20), while the spleen was palpable at ≥ 5 cm and ≥ 10 cm in 74% and 27% of patients, respectively, with baseline EuroQol visual analogue scale (EQ-VAS) score of 65.1 ± 19.4. After RUX treatment, 42.1% and 43.9% of patients demonstrated a symptom response at 24 and 48 weeks, while 38.9% and 46.8% showed a spleen response at 24 and 48 weeks, respectively. EQ-VAS increased to 71.8 ± 16.3 at 24 weeks and 69.3 ± 19.2 at 48 weeks. Furthermore, 11.2% and 25.2% of patients reported temporary and permanent discontinuation, respectively with no new adverse events reported. The interim analysis showed that ruxolitinib provided clinical benefits, a manageable safety profile, and improved quality of life for Int-1-risk subgroup patients with frequent and sustained responses with acceptable toxicity.