ATG Fresenius Research Articles

TcRαβ-depleted haploidentical transplantation results in adult acute leukemia patients

ABSTRACTIntroduction: The use of αβ+ T-cell-depleted grafts is a novel approach to prevent graft failure, graft-versus-host disease (GVHD), and non-relapse mortality (NRM) in patients undergoing haploidentical hematopoietic stem cell transplantation.Patient and method: Thirty-four patients with acute leukemia and lacking a match donor were treated with αβ T-cell-depleted allografts from haploidentical family donors. A total of 24 patients had acute myeloid leukemia (AML) and 10 had acute lymphoblastic leukemia. 84.4% of patients were in the high-risk group, and 55.9% were not in remission. The preparative regimen included thiotepa, melphalan, fludarabine, and anti-thymocyte globulin-Fresenius. Grafts were peripheral blood stem cells engineered by TcR-alpha/beta depletion.Results: Neutrophil and platelet engraftment was achieved on days +12 (range, 10.5–15) and +11 (range, 10–12). All but three patients were engrafted with full donor chimerism. Grade III-IV acute GVHD occurred in two (5.9%) patients and chronic GVHD in two (6.1%). Disease-free survival and overall survival were 42 and 54% at 1 year, respectively. AML as disease type (HR: 4.87, 95% CI: 1.50–15.87) and mother as donor (HR: 1.05, 95% CI: 1.00–1.11) were found to be independent risk factors on patient survival. Mortality and NRM in the first 100 days were 5 of 34 (14.7%) and 4 of 34 (11.7%). Relapse was the main cause of death (56.3%). T-cell reconstitution appears to be faster than that reported in published data with CD3/CD19-depleted grafts.Conclusion: αβ T-cell-depleted haploidentical transplantation may be a good alternative for high-risk patients if there are no human leukocyte antigen matched donors.

A study on impact of renal status in the outcome of patients undergoing non-renal solid organ transplant at a tertiary care centre in Kerala

Induction immunosuppression is used to reduce the incidence of acute rejection and prevent delayed graft function. The 2 rabbit anti-thymocyte globulins- thymoglobulin and Grafalon (ATG Fresenius) have been commonly used for induction immunosuppression and treatment of acute rejection in solid organ transplantation. There are very few studies comparing the efficacy and side effects of both the anti-thymocyte globulins therefore this prospective study comparing the 2 types of anti-thymocyte globulins would be of clinical interest.This prospective single center study was conducted at Rabindranath Tagore International Institute of Cardiac Sciences, Kolkata, India from April 2019 to June 2020. Sixty-two ABO-compatible renal transplant recipients were included in the study. They were divided in 2 groups of 31 patients each. One group received thymoglobulin (3 mg/kg) and the second group received Grafalon (6 mg/kg). All patients were followed up for 12 months and the 2 groups were compared for incidence of rejections, infections, graft function, patient survival, and graft survival.There was no significant difference in the incidence of rejections, infective episodes, graft function, posttransplant diabetes mellitus, graft survival and patient survival in thymoglobulin or Grafalon groups. The hematological parameters were similar in both groups at 7 days, 1 month, and 6 months of follow-up. The absolute lymphocyte count was significantly lower in the thymoglobulin group at 12 months posttransplant.Thymoglobulin and Grafalon were found to be equivalent in terms of safety and efficacy in short term, with no difference in rejections, infections, graft survival, or patient survival.

Combined liver and kidney transplantation: A single centre experience

Induction immunosuppression is used to reduce the incidence of acute rejection and prevent delayed graft function. The 2 rabbit anti-thymocyte globulins- thymoglobulin and Grafalon (ATG Fresenius) have been commonly used for induction immunosuppression and treatment of acute rejection in solid organ transplantation. There are very few studies comparing the efficacy and side effects of both the anti-thymocyte globulins therefore this prospective study comparing the 2 types of anti-thymocyte globulins would be of clinical interest.This prospective single center study was conducted at Rabindranath Tagore International Institute of Cardiac Sciences, Kolkata, India from April 2019 to June 2020. Sixty-two ABO-compatible renal transplant recipients were included in the study. They were divided in 2 groups of 31 patients each. One group received thymoglobulin (3 mg/kg) and the second group received Grafalon (6 mg/kg). All patients were followed up for 12 months and the 2 groups were compared for incidence of rejections, infections, graft function, patient survival, and graft survival.There was no significant difference in the incidence of rejections, infective episodes, graft function, posttransplant diabetes mellitus, graft survival and patient survival in thymoglobulin or Grafalon groups. The hematological parameters were similar in both groups at 7 days, 1 month, and 6 months of follow-up. The absolute lymphocyte count was significantly lower in the thymoglobulin group at 12 months posttransplant.Thymoglobulin and Grafalon were found to be equivalent in terms of safety and efficacy in short term, with no difference in rejections, infections, graft survival, or patient survival.

Comparison of combination of rituximab with low dose thymoglobulin versus low dose thymoglobulin alone as induction agent in renal transplantation

Induction immunosuppression is used to reduce the incidence of acute rejection and prevent delayed graft function. The 2 rabbit anti-thymocyte globulins- thymoglobulin and Grafalon (ATG Fresenius) have been commonly used for induction immunosuppression and treatment of acute rejection in solid organ transplantation. There are very few studies comparing the efficacy and side effects of both the anti-thymocyte globulins therefore this prospective study comparing the 2 types of anti-thymocyte globulins would be of clinical interest.This prospective single center study was conducted at Rabindranath Tagore International Institute of Cardiac Sciences, Kolkata, India from April 2019 to June 2020. Sixty-two ABO-compatible renal transplant recipients were included in the study. They were divided in 2 groups of 31 patients each. One group received thymoglobulin (3 mg/kg) and the second group received Grafalon (6 mg/kg). All patients were followed up for 12 months and the 2 groups were compared for incidence of rejections, infections, graft function, patient survival, and graft survival.There was no significant difference in the incidence of rejections, infective episodes, graft function, posttransplant diabetes mellitus, graft survival and patient survival in thymoglobulin or Grafalon groups. The hematological parameters were similar in both groups at 7 days, 1 month, and 6 months of follow-up. The absolute lymphocyte count was significantly lower in the thymoglobulin group at 12 months posttransplant.Thymoglobulin and Grafalon were found to be equivalent in terms of safety and efficacy in short term, with no difference in rejections, infections, graft survival, or patient survival.

Safety and efficacy of preoperative induction therapy using a single high dose ATG-F in renal transplantation: a meta-analysis of randomized controlled trials

This study aimed to evaluate the safety and efficacy of preoperative induction therapy using a single high dose (9 mg/kg) of antithymocyte globulin-Fresenius S (ATG-F) for patients undergoing renal transplantation. Randomized controlled clinical trials (RCTs) on the safety and efficacy of preoperative induction therapy using a single high dose of ATG-F for patients undergoing renal transplantation were searched in Cochrane Library, PubMed, EMBASE covering a period from the beginning of databases to July 2015. The meta-analysis was conducted using RevMan 5.2. Five RCTs with 346 patients were included in this study. The meta-analysis showed that the incidences of acute rejection for the patients with renal transplantation were 20.6% (37/180) in the induction therapy group using a single high dose of ATG and 42.8% (71/166) in the control group, with a combined relative risk (RR) of 0.49 and 95% confidence interval (CI) of[0.36, 0.69](P<0.000 1). The patient survival rate (1 year: RR=1.02, 95% CI[0.98, 1.06], P=0.43; 5 years: RR=1.01, 95% CI[0.94, 1.08], P=0.83) and the graft survival rate (RR=1.04, 95% CI[0.97, 1.12], P=0.24) of the two groups were similar. The incidences of CMV infection, urinary tract infection, and malignant tumor were also similar in the two groups. The induction therapy using a single high dose of ATG-F significantly reduced the incidence of acute rejection after transplantation and showed no increased incidence of urinary tract infection, CMV infection, or malignant tumor. The results of our meta-analysis suggest that the application of a high dose of ATG-F may be a safe and effective induction therapy.

Reduced platelet transfusions and earlier platelet engraftment using alemtuzumab-based conditioning regimen in allogeneic stem cell transplantation.

In patients undergoing allogeneic stem cell transplantation, conditioning regimens containing alemtuzumab instead of anti-thymocyte globulin (ATG) may result in an earlier platelet engraftment and a reduced number of platelet transfusions. We performed a retrospective, single-center, case-control study analyzing time to engraftment and transfusion needs using alemtuzumab in comparison with ATG as part of conditioning protocol. Median values for time to platelet engraftment, number of transfused platelet concentrates and number of transfused red cell concentrates were 12 versus 19.5 days (p < 0.001), 2 versus 14 (p < 0.001) and 6 versus 14.5 (p = 0.003) in the alemtuzumab and ATG group. Time to leukocyte engraftment did not differ with median 15 days in both groups. Patients in the ATG group showed a significant higher decrease in platelet count during conditioning (68 vs. 29 %, p = 0.001), leading to significant lower median platelet counts at the day of stem cell infusion (38 vs. 95.5 Gpt/l, p = 0.008), and higher values for median C-reactive protein after first antibody infusion (69.0 vs. 43.6 mg/l, p = 0.001) compared with alemtuzumab group. Test for significance was done by using Wilcoxon rank-sum test. Subgroup analysis considering the type of ATG used (Thymoglobulin vs. ATG Fresenius) revealed that differences between alemtuzumab and ATG group were more due to effects of ATG Fresenius than Thymoglobulin. The use of alemtuzumab in comparison with ATG as part of the conditioning regimen may be an approach to reduce the number of transfused platelet and red cell concentrates after allogeneic stem cell transplantation.

Randomized Trial on GvHD Prophylaxis with or without Anti-Human T-Lymphocyte Immunoglobulin ATG-Fresenius (ATG-F) in Allogeneic Hematopoietic Cell Transplantation from Matched Unrelated Donors: Final Long-Term Results after 8.6 Years Median Follow-up

Background:Previously, in 201 adult patients with allogeneic hematopoietic cell transplantation from matched unrelated donors, we demonstrated that the addition of ATG-F to standard cyclosporine, methotrexate GvHD prophylaxis (control) significantly reduces acute and chronic GvHD without negatively affecting relapse and survival [1,2,3].Methods:Now, we present final results after an extended follow-up (median 8.6, Q1 8.0, Q3 9.3 years) with regard to chronic GvHD, non-relapse mortality (NRM), relapse, relapse mortality, disease-free survival (DFS) and overall survival (OS). Additionally, we analyse the effect of ATG-F vs control on the composite endpoint severe GvHD (acute GvHD III-IV, extensive chronic GvHD) and relapse-free survival, and on time under immunosuppressive therapy. Since mortality within the first year after transplantation is usually high, we also analyse conditional survival, i.e. the OS probability after having survived 1 and 2 years after transplantation.Results:The incidence of extensive chronic GvHD after 8 years was 13.5% in the ATG-F group vs 51.8% in the control group (p<0.0001). The 8-year rates with respect to outcome were: NRM 20.5% vs 34.0% (p=0.15), relapse 35.2% vs 29.9% (p=0.54), relapse mortality 30.8% vs 28.8% (p=0.90), DFS 44.3% vs 36.1% (p=0.60), and OS 48.7% vs 36.8% (p=0.31), ATG-F vs control, respectively.ATG-F substantially increased the combined severe GvHD/relapse-free survival rate. The rates were 48.5% vs 20.4% after 1 year and 33.6% vs 13.0% after 8 years (p=0.0003), ATG-F vs control, respectively (see figure).The probability of being alive and free of immunosuppressive therapy was 46.8% in the ATG-F group and 11.2% in the control group at 8 years (p=0.0002).The survival probabilities increased when patients had survived the first year. The conditional 8 years-survival probability increased in the ATG-F group from 48.7% (unconditional) to 70.6% and 80.9% (conditional on having survived 1 and 2 years after transplantation), and in the control group from 36.8% (unconditional) to 58.5% and 71.7% (conditional on having survived 1 and 2 years after transplantation).Conclusion:The long-term follow-up of 8.6 years shows that ATG-F GvHD prophylaxis provides a sustained protective effect without increasing relapse and compromising survival. ATG-F in addition to standard cyclosporine, methotrexate as GvHD prophylaxis results in significantly improved severe GvHD/relapse-free survival. Furthermore, the stable results from our prospective trial after an extended long-term follow-up demonstrate that the choice to use ATG-F in unrelated donor transplantation after myeloablative conditioning substantially increases the probability of surviving free of immunosuppressive therapy, and thus reduces the risk associated with long-term immunosuppression.

Low Dose ATG-Fresenius Might be Effective in the Prophylaxis of Severe Graft Versus Host Disease with Low Non-Relapse Mortality

INTRODUCTIONGraft versus host disease (GvHD) is a major cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation (HSCT). ATG-Fresenius (ATG-F) has demonstrated its efficacy in reducing the risk of acute GvHD (aGvHD) and chronic GvHD (cGvHD) at a dose of 60 mg/kg (Finke J, Lancet Oncology, 2009; Sociè G, Blood, 2011), and at a dose of 30 mg/kg (Ayuk F, Biol Bone Marrow Transplant, 2008; Solano C, abstract EBMT, 2015). AIMSWe analyzed as primary endpoint whether low dose ATG-F (21-32 mg/kg) might be effective in reducing the incidence of acute and chronic GvHD. The secondary endpoints were viral infections, non-relapse mortality (NRM), disease free survival (DSF) and overall survival (OS). METHODSBetween September 2012 and December 2014, 22 patients who underwent HSCT received ATG-F in our hospital. Two patients were excluded because they received a second HSCT. We used ATG-F at a dose of 21 mg/kg (7 mg/Kg days -3,-2,-1) in the case of patients with hematologic malignancies who received a HSCT from an unrelated donor (UnD) with peripheral blood (PB) source and/or from a mismatched donor (MMD). ATG-F at a dose of 28-32 mg/kg (7-8 mg/kg days -4 to -1) was employed in aplasia. Median age was 53 years (9-68) and only 5 patients were <40 years. There were 6 patients with HLA disparity. Based on the new DRI (Disease Risk Index) classification, 11 cases ≥high risk. Only 8 patients underwent HSCT in 1st CR. The HCTI comorbidity index was ≥3 in 8 patients. A myeloablative conditioning was administered to 11 patients. Regarding CMV serology, 85% of patients were seropositive being and 35% high risk (patient +/donor -). See figure 1. RESULTSWith a median follow up of 13 months (2.8-30.3), the cumulative incidence of grade II-IV and grade III-IV aGvHD was 40% (8/20 p) and 15% (3/20 p). Eighteen patients were valuable for cGvHD. Eleven patients developed cGvHD: 4 mild, 6 moderate (33.3%), and only 1 severe (5.5%).Fifteen patients developed CMV infection (75%), which was recurrent in 3 of them. There were 2 cases of VEB plasma load and 1 patient developed EBV-PTLD (5%). Eight patients suffered from viral cystitis, in which the causal agents were JC/BK and adenovirus in 7 and 1 patients, respectively; none of these cases was severe (spontaneous resolution, lack of treatment).The incidence of 1-year NRMwas 15%. Death causes were EBV-PTLD, refractory grade IV aGvHD and multiresistant Pseudomonas pneumonia. Relapse occurred in 5 patients (4/5 high risk disease), in the first 6 months in all of them, and it was the death cause in four of them. The 1-year OS and DFS were 60% and 55%. CONCLUSIONIn our cohort, that includes patients with advanced age and high risk of GvHD (HLA disparity and PB), low dose ATG-F seems to be effective in reducing the incidence of severe acute and chronic GvHD, with low NRM. The high incidence of CMV infection might be due to the elevated rate of seropositive patients. Finally, we think that our OS, DFS and relapse rates should be asses bearing in mind the elevated number of both high-risk disease and uncontrolled disease before HSCT that includes our cohort. However, longer follow-up and a higher number of patients are necessary to confirm all these results. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Interim Results of a Multi-Center Observational Study of Current Treatment Patterns for Patients with Severe Aplastic Anemia (SAA), Very Severe Aplastic Anemia (VSAA) and Transfusion-Dependent Non-Severe Aplastic Anemia (TD-NSAA) in China

BackgroundIn China, the incidence of aplastic anemia (AA) is about 0.74/105, with 0.14/105 of severe aplastic anemia (SAA). Most of these SAA patients are treated in big medical centers or traditional Chinese medicine (TCM) hospitals, which could stand for the current practices in China. Despite the China Aplastic Anemia Consensus, published in 2010, recommended that the immunosuppressive therapy (IST) and hematopoietic stem cell transplantation (HSCT) were the standard treatment for SAA, very severe aplastic anemia (VSAA) and transfusion-dependent non-severe aplastic anemia (TD-NSAA), the current treatment options for patients with these diseases are diverse, including antithymocyte globulin (ATG)/antilymphocyte globulin (ALG) + cyclosporin A (CsA), CSA + androgen, CSA or androgen alone, only supportive care, TCM, etc. This national disease registry study aimed to describe the current clinical practice and treatment patterns for SAA, VSAA and TD-NSAA patients in China and understand their IST patterns as well as the supportive care measures.MethodsIn this prospective, multi-center, observational study, adult or pediatric patients diagnosed as acquired aplastic anemia within 3 months and met the guideline criteria of SAA, VSAA or TD-NSAA were enrolled from October 2012 to April 2014. All enrolled patients will be followed at least for one year. Each subject will be visited every 3 months in the first year and every 6 months from the second year until the patients withdraw the ICF or study close. The main evaluation criteria is the treatment patterns of SAA, VSAA and TD-NSAA which will be specified as: IST (ATG + CsA, CsA + androgen, CsA and others), HSCT, TCM, androgen, supportive care and others. The response of SAA/VSAA and TD-NSAA after each treatment, and serious adverse events, will also be evaluated by the investigators. An interim analysis is planned when all patients have been enrolled (target N=350) and will focus on their baseline characteristics and first treatment choice. This study was sponsored by Sanofi.ResultsA total of 352 patients were enrolled at 29 sites in China (SAA 221 pts; VSAA 84 pts; TD-NSAA 47 pts). The median age was 21 years (range, 0-84) and 65.1% were adults. 51.7% were male and 71.6% had ECOG PS <2. The vast majority of enrolled patients (344/352 pts, 97.7%) had no previous AA-related history. The most common onset symptom at baseline was anemia (92.9%), followed by hemorrhage (72.2%), infection (56.8%) and others (3.4%). TD-NSAA patients had less infections than SAA or VSAA patients (25.5% vs. 57.9%/71.4%). Cytogenetic abnormality were detected in 6.1% of the 245 patients who received cytogenetic test at baseline. The analysis of the primary endpoint showed 74.1% and 4.3% of the total patients received IST and HSCT at baseline, respectively. Among the patients with IST treatment, the standard ATG + CsA treatment was only applied in 26.4% of them (SAA 25.5%; VSAA 42.4%; TD-NSAA 5.4%). The other IST regimens were CsA + androgen (31.0%), CsA (31.4%) and others (11.1%). Three different brands of ATG/ALG were used in patients with IST: Rabbit ATG (75.0%), ATG-Fresenius (2.1%) and ALG-Porcine (22.9%). TCM therapy were applied in 12.8% of the total patients and were more common in SAA/VSAA patients (15.8% & 10.7%, respectively) than in TD-NSAA patients (2.1%). 2.8% of the patients received androgen therapy alone at baseline. 8 patients (2.3%) had switched their treatment pattern within 3 months before the enrolment because of unsatisfying efficacy (5 pts) or personal reasons (3 pts). Supportive care was applied in 95.7% of the total patients. The supportive care measures included blood transfusion (97.9%), antibiotics (64.1%), hematopoietic growth factors (58.8%), protective isolation (46.6%), iron chelators (0.3%) and others (2.7%). When the study initiated, the first treatment choice for all patients were IST (74.1%), HSCT (3.4%) and others (22.4%). There were no substantial difference of the first treatment pattern among SAA, VSAA and TD-NSAA groups.ConclusionsChinese AA patients received diverse treatments in real life clinical practice. Based on this interim analysis, 74.1% of the SAA, VSAA and TD-NSAA patients in China received IST. But only 26.4% of them received the standard ATG + CsA therapy. TCM therapy still played a role in the treatment, especially for SAA and VSAA patients in China. Final results including efficacy and safety profiles will be reported later. DisclosuresOff Label Use: Anti-thymocyte globulin-Fresenius is used as an immunosuppressive therapy for the treatment of aplastic anemia.

Children with Acute Leukemia Given Hematopoietic Stem Cell Transplantation (HSCT) from an HLA-Compatible Sibling, or an Unrelated Donor (UD) or an HLA-Haploidentical Relative after Alpha/Beta T-Cell Depletion Have a Comparable Outcome

Background: Allogeneic HSCT is a widely used treatment for children with acute leukemia (AL) either relapsed or at high risk of treatment failure. However, an HLA-identical sibling is available for only 20-25% of patients and an UD can be located in a suitable time only for a portion of the remaining population. HSCT from an HLA-haploidentical relative (haplo-HSCT) is now considered an alternative option, especially in view of the recent insights in graft manipulation. We recently developed a novel method of more selective T-cell depletion based on physical elimination of α/β T cells (ClinicalTrial.gov identifier: NCT01810120), shown to be effective for both preventing graft-versus-host disease (GvHD) and for conferring improved protection against infections in comparison to haplo-HSCT performed through the infusion of positively selected CD34+ cells. The initial results on 40 patients with AL were reported at the ASH Meeting in 2013 (Bertaina et al). We now present the comparison of the outcome of 80 children with AL given haplo-HSCT after α/β T-cell depletion (group 1) with that of patients transplanted from an HLA-identical sibling (group 2) or an UD (group 3) in the same time period.Patients and methods: All patients with AL were transplanted at the Bambino Gesù Children's Hospital in Rome, Italy, between December 2010 and September 2014; 80 patients were included in group 1, 41 in group 2 and 51 in group 3. Patients were offered α/β T-cell-depleted haplo-HSCT in the absence of suitable conventional donor (HLA identical sibling or 10/10 UD evaluated using high resolution typing) or if affected by rapidly progressive disease not permitting time to identify an UD. Clinical characteristics of patients assigned to the 3 groups and those of their donor are shown in Table1. All children were given a fully myeloablative regimen. No group 1 patient was given any post-transplantation GvHD prophylaxis, while patients of group 2 and 3 were given Cyclosporine-A and short-term methotrexate. Group 1 and 3 patients received ATG Fresenius® (4 mg/Kg/day) from day -5 to -3 for preventing both graft rejection and GvHD.Results: All group 2 and 3 patients had sustained engraftment of donor cells, while 1 of the 80 patients included in group 1 experienced primary graft failure and was rescued by haplo-HSCT from the other parent. The cumulative incidence (CI) of acute GvHD was 30%, 41% and 42%, respectively. Remarkably, all children of the group 1 who developed acute GvHD had a skin-only involvement, while 17% and 16.3% of those of group 2 and 3 had either gut or liver involvement (p<0.001). The CI of chronic GvHD was significantly lower in group 1 children than in those of groups 2 and 3 (p=0.02, see also Figure 1-Panel A). None of the 4 group 1 patients experiencing chronic GvHD had the extensive form of the disease, while the CI of extensive chronic GvHD of group 2 and 3 was 8% and 14%, respectively (p=0.01). Four, 1 and 6 children of patients assigned in group 1, 2 and 3, respectively, died for transplant-related causes; the CI of transplantation-related mortality (TRM) in the 3 groups is shown in Figure 1-Panel B. Relapse was the main cause of treatment failure and occurred at a comparable CI in all the 3 groups (see also Panel C of Figure 1). The 3-year probability of Event-Free Survival (EFS) was comparable in the 3 groups (Figure 1 - Panel D). In multivariate analysis, a Total Body Irradiation (TBI)-containing regimen was the only variable favourably influencing EFS of group 1 children (hazard ratio 2.93, 95% Confidence Interval 1.24-6.95). No variable influenced EFS of group 2 and 3 patients.Conclusions: Overall, these data indicate that haplo-HSCT after α/β T-cell depletion is associated with a risk of TRM and leukemia recurrence comparable to that of transplantation from an HLA-identical sibling or an UD, this translating in a similar probability of EFS. In view of the low incidence of chronic GvHD, this transplant option has to be considered a competitive alternative for children with AL in need of an allograft.TableSibling (n=41)MUD (n=51)Haplo (n=80)Sexp=0.77M273255F141925Age at Transplantation (years)10.69.49.7p=0.20Diseasep=0.23ALL343556AML71624Disease status at Transplantationp=0.13CR1203030CR2212047≥CR3013CMV serology (Donor/Recipient)p=0.001neg/neg856neg/pos8217pos/neg1411pos/pos242156Source of Stem Cellsp<0.0001BM40400PBSC11180Conditioning regimensp=0.10TBI-based262960non TBI-based152220 [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Antilymphocyte/Thymocyte Globulin for the Treatment of Steroid-Refractory Acute Graft-Versus-Host Disease: 20-Year Experience at a Single Center.

Although there is currently no consensus regarding the treatment of steroid-refractory acute graft-versus-host disease (GvHD) after hematopoietic stem cell transplantation (HSCT), antithymocyte globulin (ATG) is one of the most widely used immunosuppressive drugs in this setting. We retrospectively summarized our transplant center’s experience with 35 steroid-resistant acute GvHD patients who were treated with three different ATG preparations. Severe (grade III-IV) acute GvHD was observed either during the posttransplantation period (n= 32) or after donor lymphocyte infusion (n= 3). For secondary treatment of acute GvHD, rabbit Jurkat cell linereactive ATG (ATG Fresenius®) (n= 22), rabbit thymus cell-reactive ATG (Thymoglobulin®) (n= 9) or equine antilymphocyte globulin (ALG) (Lymphoglobulin®) (n= 4) was administered at a dose of 2-10 mg/kg/day for five consecutive days. The median time from the diagnosis of acute GvHD to the first day of infusion of ATG or ALG was 15 days (3-70 days). An overall response was observed in 15 patients (42%), with similar response rates among patients treated with any of the three ATG preparations. The overall survival (OS) of the patients did not increase in any treatment group, though the severity of GvHD and the disease status before HSCT were shown to negatively impact OS. Although responses could be achieved in steroid-refractory acute GvHD using rabbit or horse ATG, survival rates did not increase because of high mortality rates due to infection during treatment.

Lower dose anti-thymocyte globulin for GvHD prophylaxis results in improved survival after allogeneic stem cell transplantation.

In vivo T-cell depletion with anti-thymocyte globulin (ATG) can attenuate GvHD but may increase infection and relapse risks. ATG-Fresenius (ATG-F) at a dose of 60 mg/kg was standard GvHD prophylaxis in unrelated donor hematopoietic stem cell transplantation (HSCT) at our institution. We changed to an incremental reduced dose regimen of 35 mg/kg and extended ATG prophylaxis to include older matched-related donor transplants considered to be at higher risk of GvHD. A total of 265 adults with hematological malignancies receiving a first allogeneic HSCT after myeloablative conditioning between 2009 and 2014 were analyzed in this cohort study. Patients had either received higher dose (n=32) or lower dose ATG-F (n=88) or no ATG (n=145). ATG-F was associated with slower engraftment and less chronic GvHD, whereas no effect was noted on acute grade II-IV GvHD and relapse incidence. Transplant-related mortality (TRM) was lower and survival higher with lower dose, but not with higher dose ATG-F. Both ATG-F groups were associated with more viral reactivation, viral disease and bacterial blood stream infection, but not invasive fungal infection, and with slower immune reconstitution. The recently adopted strategy of using lower doses of ATG-F in unrelated and older age-related donor HSCT appears to reduce TRM without increasing disease relapse, leading to slightly enhanced survival.

Impact of Pre-Transplant Anti-T Cell Globulin (ATG) on Immune Recovery after Myeloablative Allogeneic Peripheral Blood Stem Cell Transplantation

BackgroundPre-transplant infusion of rabbit anti-T cell globulin (ATG) is increasingly used as prevention of graft-versus-host disease (GVHD) after allogeneic peripheral blood stem cell transplantation (PBSCT). However, the precise impact of pre-transplant ATG on immune recovery after PBSCT is still poorly documented.MethodsIn the current study, we compared immune recovery after myeloablative PBSCT in 65 patients who either received (n = 37) or did not (n = 28) pre-transplant ATG-Fresenius (ATG-F). Detailed phenotypes of circulating T, B, natural killer (NK) and invariant NKT (iNKT) cells were analyzed by multicolor flow cytometry at serial time-points from day 40 to day 365 after transplantation. Thymic function was also assessed by sjTREC quantification. Serious infectious events were collected up to 2 years post-transplantation.ResultsPre-transplant ATG-F had a prolonged (for at least up to 1-year) and selective negative impact on the T-cell pool, while it did not impair the recovery of B, NK nor iNKT cells. Among T cells, ATG-F selectively compromised the recovery of naïve CD4+, central memory CD4+ and naïve CD8+ cells, while it spared effector memory T and regulatory T cells. Levels of sjTRECs were similar in both cohorts at 1-year after PBSCT, suggesting that ATG-F unlikely impaired thymopoiesis at long-term after PBSCT. Finally, the incidence and rate of serious infections were similar in both groups, while ATG-F patients had a lower incidence of grade II-IV acute graft-versus-host disease.ConclusionsPre-transplant ATG-F induces long-lasting modulation of the circulating T-cell pool after myeloablative PBSCT, that may participate in preventing graft-versus-host disease without deeply compromising anti-pathogen defenses.

Effect of the immunosuppressive regimen on the incidence of cytomegalovirus infection in 378 heart transplant recipients: A single centre, prospective cohort study

BackgroundCytomegalovirus (CMV) infection is a major complication of immunosuppression after heart transplant. Recent studies suggest the actual immunosuppressive regimen may affect the risk of CMV infection. ObjectivesTo evaluate incidence, risk factors and clinical consequences of CMV infection and assess the possible differential effect of distinct immunosuppressive protocols. Study designSingle centre, prospective cohort study of 378 consecutive heart transplant recipients undergoing CMV monitoring. Preemptive treatment was the standard of care. Patients were grouped as follows: group A, without any CMV infection; group B, with CMV infection not requiring pre-emptive treatment; group C, treated for CMV infection or disease. ResultsMost recipients never required antiviral therapy because of no CMV infection/disease (group A, 31%) or CMV levels below the cut-off for pre-emptive treatment (group B, 28%). Group C recipients (41%) were significantly older than group A patients (49.1±13.2 vs. 44.8±15.1 years; p=0.028). Most cases occurred within the second month post-transplant. CMV viremia was detected in 77% and 62% of patients primed with thymoglobulin or ATG Fresenius, respectively, (OR 2.06, 95% C.I. 1.27–3.34; p=0.0034). Use of everolimus was associated with a significantly lower rate of CMV infection compared to azathioprine or mycophenolate (OR 0.19, 95% C.I. 0.09–0.39; p<0.0001). Major opportunistic infections were significantly more common in groups B and C. ConclusionIn a large and homogeneous cohort of heart transplant recipients, we observed a strong relationship between the immune suppressive regimen and CMV infection, as well as an increased incidence of other opportunistic infections in recipients with CMV infection/disease.

Effect of ATG-F on B-cell reconstitution after hematopoietic stem cell transplantation.

Antithymocyte globulin Fresenius (ATG-F) is used before hematopoietic stem cell transplantation to prevent graft rejection and graft-versus-host disease in patients with HLA-matched unrelated donors or mismatched volunteers. However, little is known about the effect of ATG-F on the reconstitution of B-cell subsets. Sixty-seven patients were longitudinally studied at day 15, day 30, and then monthly after hematopoietic stem cell transplantation. Conditioning regimes included ATG-F, which was infused at days 3, 2 and 1 at a dosage of 10mg/kg/d. Twenty-seven patients received conditioning regimes without ATG. ATG-treated patients showed a significant delay of CD19+ B cells in the early recovery period. The absolute numbers of circulating CD19+ B cells were significantly lower (P<0.05) up to 5months post-transplantation compared to non-ATG patients. The recovery of the memory compartment was delayed in both groups and did not reach normal values 1-year post-transplantation. ATG-treated patient showed significantly lower absolute numbers of circulating CD27+ memory B cells in the first-month after transplantation compared to non-ATG patients. In conclusion, treatment with ATG in the conditioning regime of patients undergoing allogeneic hematopoietic stem cell transplantation leads to a significant delay of CD19+ B cells. Thus, ATG seems also to negatively influence B-cell immune reconstitution.

Outcomes of peripheral blood stem cell transplantation patients from HLA-mismatched unrelated donor with antithymocyte globulin (ATG)-Thymoglobulin versus ATG-Fresenius: a single-center study.

Although antithymocyte globulin (ATG) had been widely used in hematopoietic stem cell transplantation from unrelated donor due to its ability to prevent acute and chronic graft-versus-host disease (GVHD), the comparative efficacy and safety of ATG-Thymoglobulin (ATG-T) and ATG-Fresenius (ATG-F) in patients undergoing HLA-mismatched allogeneic peripheral blood stem cell transplantation from unrelated donors (UR-PBSCT) has not been evaluated. Retrospective analysis of patients who underwent HLA-mismatched UR-PBSCT between January 2003 and December 2013 and received pre-transplant ATG-T at a total dose of 10mg/kg or ATG-F at a total dose of 20mg/kg was performed. Patients who received ATG-T (n=23) or ATG-F (n=28) had similar baseline demographic, disease, and transplant characteristics. There were no significant between-groups differences in the probability of acute GVHD (P=0.721) and chronic GVHD (P=0.439). ATG-F was associated with nonsignificant trends toward higher disease-free survival at 3-year follow-up compared with ATG-T (45.7±11.1 vs 61.3±9.7%, respectively, P=0.07). A significantly greater proportion of ATG-T patients experienced high fever than ATG-F patients (P<0.01) during ATG infusion. There was no difference in the rate of infection between the two treatment groups. There were less adverse effects comparing ATG-F with ATG-T. ATG-T at a total dose of 10mg/kg and ATG-F at a total dose of 20mg/kg had a similar clinical outcome in the setting of HLA-mismatched UR-PBSCT.

Polyclonal Versus Monoclonal Induction Therapy in a Calcineurin Inhibitor–Free Immunosuppressive Therapy in Renal Transplantation: A Comparison of Efficacy and Costs

BackgroundInduction therapy in renal transplantation reduces the incidence of acute rejection (AR) in expanded criteria donation (ECD) and donation after cardiac death (DCD). We compared the efficacy of Thymoglobulin (Sanofi-Aventis, Spain), ATG Fresenius (ATG-Fresenius, Spain), and Simulect (Novartis Farm, Spain) in a calcineurin-free protocol in ECD and DCD renal transplantation by evaluating patient survival, graft survival, and AR at 1 year and overall costs. MethodsAn observational retrospective study was performed using our database of 289 consecutive cadaveric ECD renal transplant recipients (n = 178) and DCD recipients (n = 111) from April 1999 to December 2011. Induction therapy consisted of Simulect, Thymoglobulin, and ATG Fresenius. Calcineurin-inhibitor (CNI)–free maintenance therapy consisted of mycophenolate mofetil or sodium and steroids. ResultsThere were no differences in the patients' demographic characteristics or patient and graft survival. One-year AR rates were equivalent (ECD: 10%, 19.1%, 17.7% versus DCD: 14.3%, 7.1%, 16.7%). Leukopenia and thrombopenia were significantly more frequent in the ECD group treated with polyclonal induction. The average total cost of transplantation was higher in the ECD group but there were no significant differences in the average total cost between ECD and DCD: 39,970.31 ± 7,732€ versus 35,058.34 ± 6,801€ (P = NS). ConclusionOur study shows the same efficacy with polyclonal and monoclonal antibody induction and a CNI-free treatment regimen in ECD and DCD renal transplantation with no differences in overall costs at 1 year after transplantation.

Once Daily Intravenous Busulphan Plus Fludarabine As New Reduced Toxicity Myeloablative Conditioning for Acute Myeloid Leukemia and MDS Allogeneic Transplantation

▪Background.Allogeneic hemopoietic stem cell transplantation is the treatment of choice for high and intermediate risk acute myeloid leukemia (AML) and for higher risk myelodysplastic syndrome (MDS). Standards preparative regimens TBI-CY and BU-CY have been widely used and extra hematologic toxicity remains a concern. Even if the combination of intravenous formulation Busulphan-CY has shown lower toxicity and suggested favorable safety and efficacy profile new drugs associations are continuously explored.Recently the association Busulphan-Fludarabine has replaced the Bu-Cy regimen with the aim to further reduce toxicity. In our Institution we started to use this regimen as preparation for allogeneic transplantation in patients with AML and MDS in October 2008 using Busulphan in a single daily infusion with the primary objective of evaluating safety and efficacy.Methods.Since October 2008 to May 2014, 23 consecutive patients (19 males, 4 females) entered this study. Median age was 56 years (range 35-63). Thirteen patients presented with first remission AML, five with first or more advanced relapse or resistant disease and five with intermediate II or high risk MDS.Conditioning consisted of intravenous Busulphan (Busilvex® 9,6 -12,8 mg/kg) given once daily in a 4 hours infusion in association with Fludarabine 160 mg /m2 for 4 consecutive days.Fifteen patients received HSCs from HLA identical siblings, 1 from a family mismatched donor, 7 from matched unrelated donors. Source of stem cells was bone marrow in 13 patients, peripheral blood stem cells in 9 patients, and both in 1 patient. CSA + short MTX was used as GVHD prophylaxis and anti-Lymphocyte globulins (Thymoglobulin® or ATG Fresenius®) was added in case of unrelated donor transplantsToxicity was evaluated by WHO toxicity scale Common Terminology Criteria for Adverse Events (CTCAE) version 3. Acute Graft versus Host Disease was evaluated in patients with engraftment and graded according to the revised Glucksberg scale. Internal review board approved study. All patients gave written informed consent to procedure.Results.All patients regularly engrafted (mean time to neutrophils >500/microliter was 13 days (range 11-15).Seven patients experienced gastro-intestinal toxicity (1 grade III mucositis, 2 grade II mucositis, 4 grade I mucositis); 3 patients had grade II cystitis. Overall grade >II toxicity occurred in a single patient (4%). Acute grade IV gastro-intestinal- GvHD occurred in 1 patient, while 12 patients presented grade I skin GvHD. Cr. GVHD occurred in 4/18 evaluable patients (moderate in 1). CMV reactivation occurred in 15/23 patients (65%), no patient developed life-threatening bacterial or fungal infection.Eight out of 23 patients have died (35%) all but one by recurrent disease and 1 by grade IV acute GvHD. Fifteen patients are alive (65%), 14 in complete remission, with a median follow-up of 8 months (range 2-37 months).Conclusion.This single Centre report, even if with limited number of patients, underlines that the association of intravenous single dose infusion Busulphan plus Fludarabine is a safe and effective conditioning regimen in AML/MDS patients. Intravenous Busulphan administered once daily is convenient, well tolerated and effective. Further prospective studies are warranted. DisclosuresNo relevant conflicts of interest to declare.

GvHD Kinetics after Haploidentical TK-Cells: In-Vivo HSV-TK Suicide Machinery Is Effective in GvHD Control and Provide a Long-Term Immune-Suppressive Treatment-Free Survival

IntroductionExtensive application of haploidentical SCT (haplo-SCT) is limited by high rate of late transplant mortality and relapse incidence associated with the delayed immune-reconstitution (IR) secondary to the procedures for severe graft-versus-host-disease (GvHD) prevention and treatment. In the past 20 years we deeply investigate the application of the paradigmatic herpes simplex virus thymidine kinase (TK) suicide gene strategy to allow the selective elimination of genetically modified donor T cells during GvHD, while sparing IR with effective graft-versus-leukemia and graft-versus-infectious effects.Aim of the studyHere we report the incidence, characterization, stratification, treatment and outcome for both acute (a-) and chronic (c-) GvHD in haplo-SCT after TK-cells infusion.MethodsWe included for analysis 57 adult patients (pts, median age 53 years – r 17-66) who underwent an haplo-SCT according to TK-trial (Ciceri, Bonini et al, Lancet Oncol 2009; Phase III TK008, NCT0091462), between 2002 and 2014 at our Center. Data were collected from our Institutional database. A written consent was given by pts allowing the use of medical records for research in accordance with the Declaration of Helsinki.All consecutive pts receiving graft after selection of peripheral CD34+ cells - CliniMacs one-step procedure - were selected. No immune-suppression was introduced after SCT as GvHD prophylaxis. In vivo T-cell depletion with ATG (Fresenius) was administered in all pts.Donor lymphocytes genetically engineered to express the TK gene were infused in 34/57 pts (median 2 infusion/pts), 25/34 achieved IR (median time from SCT 84 days – r 18/182; median time from last TK-cells infusion 27 days – r 13/42).ResultsTwelve of 25 immune-reconstituted pts developed a-GvHD (grade I–IV; median time of onset 84 days post SCT – r 20/162; 19 days post last TK-infusion – r 8/54) and one developed c-GVHD. Direct association of TK-cells and GvHD was confirmed by vector-encoded protein immunostaining of lymphocytes infiltrating affected lesions.Eleven pts needed GvHD treatment: 4 pts received ganciclovir iv (GCV 5 mg/Kg/12h/14 days), 7 pts valganciclovir per os (VGCV 900 mg/12h/14 days). Both GCV and VGCV were effective in control clinical manifestations of GvHD in a median of 14 days (see figures 1. and 2.) and resulted in a significant reduction in numbers of circulating TK-cells, without reduction of CD3+ TK-negative lymphocytes maintaining long-term IR (see table). In 5 pts additional concomitant treatment with low-dose steroid (prednisone <0.5mg/kg per day for a median of 2 weeks) was given.A pt who presented severe gut and liver GvHD and one who received at SCT an high dose of unmanipulated lymphocytes (5.4x105/Kg) – were successfully treated with a combined therapy of prednisone and cyclosporine or rapamicine in association with GCV.Patient TK44 developed a severe classic de novo c-GVHD, with sclerodermatous lichenoid skin and mouth features plus moderate dry-eye symptoms that was successfully treated with VGCV and a transient course of mycophenolate mofetil (2 g per day) over a 2 months period.No cases of quiescent or progressive c-GvHD was observed after a median follow-up of 679 days (r 139/4035).ConclusionIn our 12-years experience we can confirm that infusion of TK-cells is effective in accelerating IR while controlling GvHD, providing a long-term immunosuppressive therapy free survival in absence of GvHD related deaths or long-term complications.Abstract 548Despite a consistent reduction in TK-cell numbers, the GCV/VGCV treatment of GVHD did not impair or prevent long-term IR.TK-cells infused / Kg x107Time from SCT to GvHD (days)Time from last TK-cells to GvHD (days)Description (acute – chronic, grade)Before GCV/VGCVAfter GCV/VGCVGvHD outcome ,days after 1st dose of GCV/VGCVTK+ cells/mclTK-cells/mcl% of TK+,tot CD3+cellsTK+ cells/mclTK-cells/mcl% of TK+, tot CD3+cellsTK519115A II3624812.773781.8CR 21TK619851A I21327044.1///CR NATK8102017A IV20722457.9243640.2CR 20TK162.2208A II909947.6256926.6CR 4TK202.43028A II2213913.7131299.2CR 29TK250.416214A II2312316131846.8CR 7TK38111054A III9943615.6155032.0CR 10TK441159146C severe123992.903030CR 84TK4719019A II35142245.43422213.3CR 3TK5016641A II35523859.9268822.8CR 18TK1007A1.211730A I2014612///CR NATK1011A1.067820A II119711.371315CR 90TK1014A0.961510A II114126.82852.3CR 8 [Display omitted] [Display omitted] DisclosuresBonini:MolMed S.p.A.: Consultancy. Colombi:MolMed: Employment. Lambiase:MolMed S.p.A: Employment. Bordignon:MolMed: Employment.

Belatacept-based, ATG-Fresenius-induction regimen for kidney transplant recipients: A proof-of-concept study

Belatacept provides effective immunosuppression while avoiding the nephrotoxicities associated with calcineurin inhibitors (CNIs). However, existing belatacept-based regimens still have high rates of acute rejection. We hypothesized that therapy with belatacept, mycophenolic acid (MMA), steroids and induction therapy with rabbit anti-thymocyte globulin Fresenius (ATGF), rejection rate could be reduced. Prospective, single center, proof-of-concept study including males and females aged ≥18years, Epstein–Barr virus (EBV)-seropositive recipients of a first, HLA non-identical, live or deceased donor kidney allograft. Only patients with a calculated panel reactive antibody score of 0% were included. Three donors were positive for Chagas disease. Six of twelve patients had at least one infection and five were readmitted to the hospital for treatment. One patient had a Trypanosoma cruzi infection via the graft treated successfully. Median cold ischemia time for the transplant patients with a deceased donor was 21.5h. Mean serum creatinine levels at 1, 3 and 6months were 1.76±0.59, 1.55±0.60 and 1.49±0.60mg/dl, respectively. Two of twelve patients experienced clinical, biopsy-proven rejection, successfully treated with methylprednisolone. No patient developed post-transplant lymphoproliferative disorder (PTLD) or any other malignancy and no patient lost their graft or died during follow-up. The potential of this approach makes it worthy of further investigation.