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Resume Les cellules T a recepteur antigenique chimerique (CAR T-cells) sont une nouvelle classe de traitements anticancereux produits en manipulant genetiquement des lymphocytes T autologues ou allogeniques afin de generer l’expression d’un recepteur chimerique dirige contre un antigene exprime sur la membrane de cellules tumorales. En Europe, le tisagenlecleucel (Kymriah™) dispose d’une autorisation de mise sur le marche (AMM) pour le traitement de la leucemie aigue lymphoblastique B en rechute/refractaire chez l’enfant et le jeune adulte et celui du lymphome B diffus a grandes cellules (LBDGC) en rechute/refractaire. L’AMM de l’axicabtagene ciloleucel (Yescarta™) porte sur le traitement du LBDGC et du lymphome primitif a cellules B du mediastin en rechute/refractaire. Les deux medicaments de therapie genique aujourd’hui autorises en Europe sont constitues de cellules T autologues genetiquement modifiees pour exprimer un CAR dirige contre CD19, un antigene exprime tout au long de la differenciation lymphoide B et sur de nombreuses hemopathies malignes B. Ce travail collaboratif fait partie d’une serie de travaux d’experts et a pour but de proposer des conseils pratiques pour aider les preleveurs a effectuer le prelevement des cellules mononucleees sanguines autologues et fournir le materiel cellulaire de depart a l’industriel fabricant, en vue de la production pharmaceutique de CAR T-cells.

International audience; CAR T-cells are anti-cancer immunocellular therapy drugs that involve reprogramming the patient's T-cells using a transgene encoding a chimeric antigen receptor (CAR). Although CAR T-cells are cellular therapies, the organization for manufacturing and delivering these medicinal products is in many ways different from the one for hematopoietic cell grafts or donor lymphocyte infusions. The implementation of this innovative therapy is recent and requires close coordination between clinical teams, the therapeutic apheresis unit, the cell therapy unit, the pharmaceutical laboratory, and pharmacy. Apart from the regulatory texts, which are regularly modified, and the specific requirements of each pharmaceutical laboratory, there is currently no guide to help the centers initiating their activity and there is no specific indicator to assess the quality of the CAR T-cell activity in each center. The purpose of the current harmonization workshop is to clarify the regulatory prerequisites warranted for a center to have a CAR T-cell activity and to propose recommendations for implementing quality tools, in particular indicators, and allowing their sharing.

Lymphodepletion followed by infusion of suicide gene-transduced donor lymphocytes to safely enhance their antitumor effect: a phase I/II study

Erythrocytapheresis (ER) can improve outcome in patients with sickle cell disease (SCD). A good vascular access is required but frequently it can be difficult to obtain for sickle cell patients. Arterio-venous fistulas (AVFs) have been suggested for ER in SCD supported by limited evidence. We report the largest cohort of ER performed with AVFs from three French SCD reference centers. Data of SCD patients undergoing ER with AVFs in the French SCD reference center were retrospectively collected. The inclusion criteria were: SS or Sβ-Thalassemia and AVF surgery for ER. SCD-related complications, transfusion history, details about AVF surgical procedure, echocardiographic data before and after AVF, AVF-related surgical and hemodynamical complications were collected. Twenty-six patients (mean age 20.5 years, mean follow-up 68 months [11-279]) were included. Twenty-three patients (88.5%) required central vascular access before AVF. Fifteen AVFs (58%) were created on the forearm and 11 (42%) on the arm. Nineteen patients (73%) had stenotic, thrombotic or infectious AVF complications. A total of 0.36 stenosis per 1,000 AVF days, 0.37 thrombosis per 1,000 AVF days and 0.078 infections per 1.000 AVF days were observed. The mean AVF lifespan was 51 months [13-218]. One patient with severe pulmonary hypertension worsened after AVF creation and died. We report the first series of SCD patients with AVF for ER, demonstrating that AVFs could be considered as a potential vascular access for ER. Patients with increased risk for hemodynamic intolerance of AVFs must be carefully identified, so that alternative vascular accesses can be considered. Am. J. Hematol. 92:136-140, 2017. © 2016 Wiley Periodicals, Inc.

To the editor: The risk for a hepatitis C virus (HCV) RNA–positive donor to transmit the virus to the recipient through a hematopoietic stem cell transplantation (HSCT) is constant.[1][1] Although this situation is not an absolute contraindication to donation from an HLA-identical sibling,[2][2

Background A decrease in hematocrit lengthens bleeding time. The authors studied the role of hematocrit variations in an experimental model of arterial thrombosis and bleeding. Methods The Folts model was used in 24 rabbits. After anesthesia was induced and common monitors were positioned, the right common carotid artery was exposed and a 60% stenosis was induced. A compression injury of the artery was then produced, which triggered a series of cyclic episodes of thrombosis and clot lysis (cyclic flow reductions [CFRs]). After counting the number of CFRs that occurred in 20 min (CFR1), the animals were assigned randomly to one of three groups (n = 8 in each group): control, hemodilution with rabbit homologous platelet-rich plasma, and hemodilution with gelatin solution and then reinfusion of the shed blood. The effect of hemodilution with replacement by platelet-rich plasma or by colloid was observed by recording the number of CFRs during another 20-min period (CFR2). A third period of observation (CFR3) followed shed blood reinfusion in the gelatin solution group. Ear immersion bleeding time was recorded after each CFR period. Results In the two experimental groups, the decrease in hematocrit (from 36 +/- 3% to 23 +/- 2% and from 38 +/- 3% to 23 +/- 2%, respectively; mean +/- SD) abolished CFRs (from a median of 4 to 0 and 7 to 0, respectively) and significantly lengthened bleeding time (from 76 +/- 24 s to 114 +/- 36 s and from 84 +/- 37 s to 127 +/- 29 s, respectively). Blood reinfusion in the group that received the gelatin solution caused CFR to reappear (CFR3 = 4). Conclusions Decreases in hematocrit reduced the cyclic arterial thrombosis rate and increased the bleeding time in the rabbits in this study. Hematocrit normalization caused thrombosis to reappear.

Introduction Erythracytapheresis (ER) can improve outcome in patients with sickle cell disease (SCD). A good vascular access is required but can be difficult to obtain for sickle cells patients. Arterio-venous fistula (AVF) has been suggested for ER in SCD supported by limited evidence. We report the largest cohort of ER performed with AVF from three French sickle cell disease reference centers. Methods Data of SCD patients undergoing ER with AVF in the French SCD reference center were retrospectively collected. The inclusion criteria were: SS or Sβ-Thalassemia and AVF surgery for ER. AVF for hemodialysis were excluded. SCD-related complications, transfusion history, details about AVF surgical procedure, echocardiographic data before and after AVF, AVF-related surgical and hemodynamical complications were collected. Results Twenty-six patients (mean age 20.5 years; median follow-up 68 months [11; 279]) were included. Twenty-three patients (88.5%) required a central vascular access before AVF. Fifteen AVF (58%) were created on the forearm and 11 (42%) on the arm. Nineteen patients (73%) had stenotic, thrombotic or infectious AVF complications. The median AVF lifespan was 34 months [13; 66]. One patient with severe pulmonary hypertension worsened after AVF creation, and died. Conclusions We report the first series of SCD patients with AVF for ER demonstrating AVF could be considered as a potential vascular access for ER. Patients with increased risk for hemodynamic intolerance of AVF must be carefully identified, in order to consider alternative vascular accesses. Disclosures Ribeil: Bluebirdbio: Consultancy; Addmedica: Research Funding.

Allogeneic hematopoietic stem cell transplantation (SCT) is a widely used, cost-intensive procedure. Although pretransplant nonmyeloablative (NMA) or reduced-intensity conditioning regimens appear very promising, prospective studies comparing this approach with the conventional myeloablative (MA) approach in specific hematologic diseases are necessary, especially in patients in whom the conventional approach is not contraindicated. Cost may be an important factor in the decision-making process. We compared the costs of MA and NMA transplants in patients with acute myeloid leukemia (AML). We estimated 1-year resource utilization in 12 consecutive MA patients (median age: 39 years) and in 11 consecutive NMA patients (median age: 58 years) who underwent HLA-identical sibling SCT for AML. Resources care expenses were valued using the average daily rate for personnel costs, supplies, and room costs. Other data were directly collected from the patients' charts. Despite a trend for lower costs in NMA patients during the first 6 months, costs during the 6-12-month period were significantly higher after NMA due to late complications and readmissions (P=0.03). Finally, mean 1-year costs were not different in MA and NMA patients (P=0.75). Prospective studies comparing conventional and NMA approaches in homogeneous populations should include economic items.

Background Donor lymphocyte infusions (DLI) can produce lasting remissions in patients with relapsed chronic myeloid leukemia (CML), but are less effective in non-CML diseases. Chemotherapy-induced lymphodepletion prior to DLI, achieved with cyclophosphamide (Cy) and fludarabine (Flu), has been shown to enhance activation of donor lymphocytes and cause significantly more acute graft-versus-host disease (GVHD) than DLI alone. To safely balance the toxic versus beneficial effects of activated donor lymphocytes, we combined lymphodepleting chemotherapy with the infusion of donor T cells engineered to carry a suicide gene to treat patients with aggressive hematologic malignancies. Methods Donor T cells were transduced with a retroviral vector expressing the Herpes simplex thymidine kinase (TK) suicide gene and the human Thy-1 selection marker and expanded in culture for 15 to 19 days prior to their infusion. In this phase I/II trial, the safety and efficacy of Cy/Flu/DLI-TK was studied between February and December 2011 in 10 adults with relapsed multiple myeloma (n=5) or myelodysplasic syndrome/acute leukemia (n=5). One had previously failed to respond to at least one standard DLI while others had not received any DLI before inclusion. All were free of immunosuppressive therapy at inclusion. Patients were infused with a mean cell-dose of 5 (range: 1-10) x106 CD3+ cells/kg of which 98% were TK+ cells (range: 97%-99%). DLI products contained a mean ratio of 0.6% (range: 0.1-1.6) CD4+FoxP3+Helios+ regulatory T-cells. This trial was registered at www.clinicaltrials.gov as NCT 01086735. Results The Cy/Flu regimen was profoundly lymphodepleting and led to a mean 3-day period of neutropenia below 500 PMN/µL. Three patients developed acute GVHD following TK+ cell infusion. One patient had a grade I cutaneous GVHD resolving with local steroids. In another patient with grade III cutaneous and digestive involvement, intra-venous administration of ganciclovir (GCV) led to the complete and lasting resolution of symptoms correlated with clearance of TK+ cells in peripheral blood. A third patient had a grade III liver GVHD. Due to only partially controlled leukemia at the time of DLI, GCV treatment was postponed for one week after GVHD onset in order to support a putative GVL effect. Treatment with GCV led to the rapid disappearance of TK+ cells in peripheral blood and liver (see Figure) but without clinical improvement after 2 weeks, so that an additional immunosuppressive therapy should be instituted. Six patients, including one of the 2 treated with GCV, experienced relapse/progression of their malignancy and received additional anti-cancer therapy. With a median follow-up of 22 months after Cy/Flu/DLI-TK, 6 patients are alive, 5 of them being disease-free. In patients not treated with GCV, TK+ cells could still be detected in peripheral blood till at least 12 months after their infusion. Conclusion Lymphodepletion followed by suicide-gene-transduced T-cell infusion may help to safely enhance the immune activity of DLI, which could be further improved by regulatory T-cell depletion (Maury et al, Science Translat Medicine 2010). Disclosures: No relevant conflicts of interest to declare.

Follicular lymphomas have an indolent evolution with a median survival ranging between 8–10 years. At relapse, high-dose therapy followed by autologous stem-cell transplantation (ASCT) can be considered as an alternative to conventional chemotherapy. However, efficacy of this strategy remains controversial. The purpose of our retrospective study is to evaluate ASCT in the pre and post rituximab era as consolidation after 2nd or 3rd remission (at least PR). Between March 1989 and Apr 2004, 54 pts were treated at relapse with ASCT in our institution. At initial diagnosis, median age was 47 yrs (range 24–61) and FLIPI score was ≥ 3 in 18%. ASCT was performed in 2nd remission in 43 cases and in 3rd remission in 11 [median delay diagnosis-ASCT=44 months (range 7–139) and 53 months (range 21–227), respectively]. The conditioning regimens used were: VP16/cyclophosphamide/TBI in 33 cases, cyclophosphamide/TBI in 9, BEAM in 10 and cyclophosphamide/busulfan in 2. After ASCT, 49 pts achieved CR, 4 achieved PR and one pt progressed. In Dec 2004, with a median follow-up of 4.7 yrs, 27 pts (50%) had relapsed after ASCT with a median time to relapse of 12 months (range 2–95) and 18 pts have died. Causes of death were: lymphoma recurrence in 8 cases, secondary malignancy in 6 cases (3 MDS/AML, 2 radiation-associated solid tumors, 1 EBV associated lymphoma after a new salvage treatment including allogenic transplantation), and late infection in 4 cases, 2 of them occurring in remission (varicella and septicaemia) and 2 others after a new salvage therapy (cellulitis during chemotherapy-induced neutropenia and HHV6 encephalitis after allogenic transplantation). Ten-year overall survival (OS) from initial diagnosis was 68%. Five-year OS and event-free survival after ASCT were 74 and 52%, respectively. Patients treated at relapse before 1998 did not receive rituximab (rituximab-naive pts: n=29) and those treated after 1998 received a rituximab-based salvage regimen before ASCT (rituximab-treated pts: n=25). The main characteristics of the two populations were as indicated in the table below: | | rituximab-naive group | rituximab-treated group | |:--------------------------------------------------------------------------------:| --------------------- | ----------------------- | | N | 29 | 25 | | FLIPI at initial diagnosis (Low/Intermediate/High) % | 41/48/11 | 27/46/27 | | Median age at ASCT (yrs) | 50 (range35–60) | 52 (range 30–62) | | ASCT performed in 2nd remission | 23 | 20 | | ASCT performed in 3rd remission | 6 | 5 | | Median duration of response following last treatment line prior to ASCT (months) | 21 (range 1–91) | 11 (range1–49) | After adjusting for the follow-up (median follow-up of the rituximab-treated group: 3.8 yrs), comparison between the two groups of pts treated with ASCT at relapse shows a significantly better OS of the rituximab-treated group as compared to that of the rituximab-naive group (100 vs 61% at 4 years, p=0.01). These data suggest that the well-established efficacy of rituximab in FL is not abrogated by consolidative ASCT delivered at relapse in pts not previously treated with rituximab and further emphasize the superiority of immunochemotherapy over chemotherapy alone.