Survival of pomalidomide-treated PMF patients was compared to other PMF patients from the Mayo Clinic database, after matching the two populations for disease stage according to the Dynamic International Prognostic Scoring System – plus and STAT inhibitors selleck hematologic study entry criteria.Survival data were prepared by the Kaplan?Meier method and compared by the log-rank test.Cox proportional hazard regression model was used for multivariable analysis.P values less than 0.05 were considered significant Results and Discussion From May, 2007 to January, 2010, 94 Mayo Clinic patients with MF were enrolled in two consecutive clinical trials that included pomalidomide; 19 were enrolled in a phase-1 dose escalation study , 58 in an extension of the phase-1 study using low-dose single agent pomalidomide , and 17 in a phase-2 randomized study.Patient characteristics at study entry are outlined in Table I and additional patient and protocol details are as previously described.Follow-up information was updated in August, 2011.To date, pomalidomide therapy has been discontinued in 86 patients at a rate of 68% at 1 year and 89% at 2 years.Eight patients remained on treatment for a median duration of 34 months.
Overall anemia response, per IWG-MRT criteria, was 27% and was more likely to occur in the absence of marked splenomegaly defined as palpable spleen size _10 cm , presence of <5% circulating blasts , or presence of JAK2V617F.Anemia response rate in the absence of marked splenomegaly, Irinotecan presence of <5% circulating blasts and absence of JAK2V617F was 53% compared to 21% or 0%, respectively, in the presence of one or two of the following: marked splenomegaly, _5% circulating blasts, absence of JAK2V617F.In addition, a 50% or more increase in circulating basophil count in the first month of treatment predicted anemia response.Response was not affected by karyotype, DIPSS-plus risk profile, or leukocyte count.Median response duration was 16 months.Only one patient met IWG-MRT criteria for spleen response.Among 34 patients with baseline platelet count of <100 3 109/L, 20 experienced a _50% increase in platelet count, which was predicted by the presence or absence of anemia response.Grade 1 sensory neuropathy developed in 4 of 30 patients treated for _12 months.Symptoms were described as numbness of the hands and feet, occasionally involving lips and face.In all instances, symptoms of neuropathy first developed while patients were receiving _2 mg/day dose and onset ranged from 2 to 39 cycles into treatment.Three of the four patients with drug-induced neuropathy remained on a reduced dose with stable symptoms for a period of 34?45 cycles.One of these patients also experienced progressive chorea that was felt to be unrelated to pomalidomide therapy.None of the patients were previously exposed to thalidomide or lenalidomide therapy.