Background Extracorporeal photopheresis (ECP) is an efficient and established therapy to treat acute and chronic graft vs host disease (GVHD). Using an “off‐line” method, the first step (mononuclear cell [MNC] collection) is decisive, as long as a high MNC yield and purity in the collected product is desirable. Two “off‐line” devices were compared: the COBE Spectra and the Spectra Optia (Terumo BCT), using both continuous and intermittent protocols. Patients and methods Twelve patients with GvHD (7 acute/5 chronic) were enrolled between June 2014 and May 2015 and were alternatively assigned for each procedure to either the COBE Spectra or the Spectra Optia cell separator. Patients characteristics and procedure/product parameters were analyzed. Results Two hundred procedures (100 per device) were included. The Spectra Optia system showed higher total nucleated cells and MNC collection efficiencies (18.6(10.2‐29.7) vs 7.9(4.1‐14.8)% and 43.6(20.3‐59.5) vs 23.3(11.4‐37.1)%, P < .001) and monocyte and lymphocyte collection efficiencies (55.2(17.7‐83.2) vs 22.8(9‐38.9)% and 38.3(26.7‐53.4) vs 22.2(9‐38.9)%, respectively, P < .001). Absolute platelet loss (PL) and PL per liter of blood processed were significantly lower in the Spectra Optia group (22.9(18.3‐28.1) vs 33.6(26.5‐41.1)%, P < .001 and 3.7(3.1‐4.5) vs 4.3(3.5‐4.2)%, P = .01, respectively). However, granulocyte contamination was higher (4.5(1.3‐36) vs 1.2(0.4‐5.7)%, P < .001) and a higher product haematocrit was obtained with the Spectra Optia (1(0.5‐1.6) vs 0.3(0.2‐0.5)%, P < .001), without an impact on irradiation time. Conclusions In our study, Spectra Optia proved to be safe and effective in collecting MNC with high yield and purity for ECP in GvHD.

Imatinib mesylate and the newer BCR-ABL tyrosine kinase inhibitors are the standard therapy for chronic myeloid leukemia. Although these are remarkably effective drugs, some mechanisms of resistance have been identified including drug-to-drug interactions. Here we present the case of a chronic myeloid leukemia patient with an inadequate response to imatinib due to concurrent phenytoin administration. Conspicuously low imatinib plasma trough levels were documented. Imatinib dose was increased from 400 to 800 mg with good response. In conclusion, drug-to-drug interactions should be ruled out in cases of resistance to tyrosine kinase inhibitor treatment. Potent inducers of cytochrome P450 isoenzyme CYP3A4, as phenytoin, could induce inadequate responses due to increased imatinib clearance and low imatinib trough plasma levels. Thus, this interaction should be avoided. When this is not possible, dose escalation of imatinib and measurement of plasma levels, if available, is recommended.

Eosinophilia has rarely been described with lenalidomide. This case shows a clear temporal relationship between lenalidomide and eosinophilia.

Introduction The human recombinant filgrastim G-CSF has been widely used for mobilisation of CD34+ cells of healthy donors (HD) since 90´s. In 2008, G-CSF biosimilars were approved by the European Medicines Agency for the same indications as those authorized for original filgrastim (Neupogen®). These new drugs were authorized on the basis of extensive physicochemical and biological protein characterization and pharmacodynamics data as well as clinical comparative studies in the particular field of chemotherapy–induced neutropenia in patients with solid tumors. Since then, the reported experience on the use of G-CSF biosimilars for PBSC mobilisation has been very limited particularly, in the setting of HD mobilization for allogeneic transplant. We report our single center experience on the use of filgrastim biosimilar Zarzio® (Sandoz Biopharmaceuticals®) for mobilization of HD, compared with a cohort of donors mobilized with the original filgrastim. Methods Retrospective comparative analysis of all consecutive HD undergoing a 1st attempt of PBSC mobilisation using 10 mcg/Kg/24h x4 days G-CSF (Filgrastim biosimilar Zarzio® [case cohort] or Filgrastim, Neupogen® [control cohort]) and collected with the same cellular separator (Cobe Spectra, Terumo®). Apheresis was initiated on day 5 and was daily repeated, if needed, in order to achive at least 3.5 x106/Kg patient body weight (PBW). SAEs were also analysed in both cohorts. For the porpoise of the post-transplant engraftment analysis both cohorts were independently compared according to the grade of HLA compatibility (HLA identical vs Haploidentical). Volunteer HD were excluded from the engraftment analysis. Non-parametric test was used for 2 cohorts comparison. Results Forty five HD cases and 41 controls undergoing G-CSF mobilization between June-09 and April-14 were eligible for the analysis. Donor features were comparable for both cohorts (table 1). Doses of G-CSF required, pre-apheresis analytical parameters, leukapheresis procedures, processed volume and collected graft parameters were found similar in both groups (table 1). All donors collected more than 2 x106/Kg CD34+ cells. Cummulative incidence of engraftment at day 30 was 100% for both cohorts, the HLA identical setting (p=0.53) and the haplo sub-group (p=0.25). AES were not observed for both cohorts. Conclusions In our experience, efficacy of G-CSF biosimilar Zarzio® was similar to reference filgrastim (Neupogen®) in terms of dose administered, CD34+ cells collected, stem cell functionality and engraftment. No SAEs were found for both cohorts. These preliminary results should be confirmed with a longer follow up within a prospective randomized trial. Figure 1 Figure 1. Figure 2 Figure 2. Disclosures No relevant conflicts of interest to declare.

Introduction: Extracorporeal photopheresis (ECP) is a treatment modality that entails leukapheresis followed by mixing the buffy coat with 8-methoxypsoralen (8-MOP) and exposing it to UVA light. The buffy coat is then returned to the patient. ECP may be performed employing two different techniques: an on-line and off-line procedure. The off-line system includes two steps: a processing of buffy coat before reinfused to the patient. The treatment is thought to have an immunomodulatory effect and is most commonly used to treat cutaneous T cell lymphoma, acute and chronic graft-versus-host disease (GVHD), and heart and lung allograft rejection. The exact mechanism and optimal cells dose to be treated is unknown. At the present time, a standard protocol is used generally without considering peripheral blood (PB) leukocytes counts or lymphocyte subpopulations (LP) of the patient. With the off-line system, PB leukocytes counts and LP analysis may be useful to choose the amount and distribution of cells to be infused. The first objective of this study is to examine the quantitative correlation between PB LP and the buffy-coat in order to set individualized guidelines of treatment. Once this relationship is understood, the PB LP may serve as a surrogate marker for cell dose treated and help predicting the efficiency of ECP. The second objetive of this study is to examine the mean performance of the buffy coat LP categorized according to PB leukocytes counts (<1.5 x 109/L and >1.5x 109/L). Patients and methods: Twenty two consecutive patients with refractory GVHD were prospectively studied, from november 2009 to may 2014. Apheresis procedures were perfomed with COBE Spectra system (Terumo BCT®, Lakewood, CO, USA; version 7.0) by processing 1.5-2 times the patient blood volume. The product was transferred to a UVA-permeable bag (UVA, Macopharma, France), added 5 mL (0.1 mg) of 8-methoxypsoralen (8-MOP) aqueous solution (S.A.L.F.®, Cenate Sotto, Italy), exposed to UVA irradiation (Macogenic G2, Macopharma®), and then reinfused. Peripheral blood sample was drawn before ECP. Just before reinfused, buffy coat sample was drawn. Spearman correlation analysis was performed between the LP CD3+CD4+, CD3+CD8+, CD19+, NK of the preapheresis peripheral blood patient and the buffy coat infused analyzed by multiparameter flow cytometry 5 colors (FC500-Beckman Coulter®) in the total sample and in three groups according to preapheresis leukocytes counts (<2.5, 2.5-7.5, >7.5x 109/L). The mean performance was calculated: CD3+CD4+, CD3+CD8+, CD19+, NK+ LP count in buffy coat/ CD3+CD4+, CD3+CD8+, CD19+, NK+ PB /ml x treatment volume (ml) x 100. The mean performance of the buffy coat LP categorized according to preapheresis leukocytes counts (<1.5x 109/L and >1.5 109/L) were compared by Mann-Whitney test. Results: A total of 22 patients and 136 procedures were included in the final analysis. CD3+CD4+, CD3+CD8+, CD19+, NK LP in peripheral blood significantly correlated with those in buffy coat collected by COBE Spectra system, r= 0,74, 0.78, 0,92, 0,39 respectively (table 1). The LP mean doses and mean performance in buffy coat infused are specified in Table 1. The correlations was stronger in all LP with PB leukocytes counts <2.5 x 109/L (table2). We have not found any statistical correlation between the performance of the LP CD3+CD4+, CD3+CD8+, CD19+, NK according to PB leukocytes counts (<1.5x109/L and >1.5x109/L). Conclusions: The buffy coat contains great variability in lymphocyte subpopulations with predominant levels of CD3+CD8+. There is a robust linear relationship between all PB and buffy coat LP. The mean performance LP was around 40% and it was not related to very low PB leukocyte count (<1.5x109/L). The correlation was stronger with lower leukocytes counts in PB. If we could demonstrate a relationship between cell doses infused and clinical response, we could plan the necessary dose for each patient according to the PB leukocyte count and LP preapheresis. Figure 1 Figure 1. Figure 2 Figure 2. Disclosures No relevant conflicts of interest to declare.