Еarly splenic response to ruxolitinib correlates with survival: a russian retrospective multicenter study in patients with myelofibrosis

We retrospectively analyzed the effectiveness of ruxolitinib in patients with myelofibrosis (MF) in real clinical practice in Russia. The study included 42 patients with MF with an average age of 56 years from 10 inpatient and outpatient clinics. The majority of patients (55 %) belonged to the intermediate risk group 1 on the DIPSS scale, 86 % had massive splenomegaly and 88 % had constitutional symptoms. The average initial dose of ruxolitinib was 15 mg twice a day. At the time of analysis, 74 % of patients continued taking ruxolitinib with an average duration of therapy of 20 months. A decrease in the palpable size of the spleen by at least 50 % was recorded in 36 % and 46 % of patients assessed after 3 and 6 months of treatment, respectively. A correlation was found between OV, initial splenomegaly and splenic response after 3 months of therapy. It should be noted that no deaths were recorded in patients with a decrease in the size of the spleen by ≥ 50 %. There were no cases of discontinuation of treatment due to side effects. In general, in our retrospective study, ruxolitinib effectively controlled constitutional symptoms and reduced the size of the spleen in patients with MF. An early splenic response after 3 months of therapy is apparently a prognostic factor for OS, and a decrease in the size of the spleen by less than 25 % should be considered as treatment ineffectiveness in patients with MF taking ruxolitinib.