Conditioning Regimen For Transplantation Research Articles

Superior Survival After Unrelated Allogeneic Stem Cell Transplantation With Low-Dose ATG Compared to Low-Dose TBI in Myeloablative Fludarabine/Busulfan-Based Regimen for MDS on Behalf of the Adult MDS Working Group of the JSTCT

The fludarabine/intravenous busulfan 12.8 mg/kg (FB4) regimen is an effective conditioning regimen in allogeneic hematopoietic stem cell transplantation for myelodysplastic syndrome (MDS); however, limited data is available on the prognostic impact of FB4 with low-dose anti-thymoglobulin (ATG ≤ 5 mg/kg) or low-dose total body irradiation (TBI ≤ 4 Gy). Therefore, we retrospectively evaluated the outcomes in 280 adults with de novo MDS who underwent their first transplantation from an unrelated donor between 2009 and 2018. Median age was 61 years (range, 16 to 70 years). In the FB4 alone (FB4), FB4 plus ATG (FB4-ATG), and FB4 plus TBI (FB4-TBI) groups, 3-years overall survival (OS) rates were 39.9%, 64.8%, and 43.7%; 3-years nonrelapse mortality (NRM) were 32.1%, 22.1%, and 27.1%; and 3-years relapse incidences were 34.7%, 21.2%, and 28.9%, respectively. The multivariate analyses showed that FB4-ATG group significantly correlated with better OS (hazard Ratio [HR], 0.51; 95% confidence interval [CI], 0.27 to 0.95; P = .032) than FB4 group. FB4-ATG group tended to correlate with lower NRM (HR, 0.36; 95% CI, 0.13 to 1.06; P = .063) than FB4 group. In comparison with FB4-TBI group, FB4-ATG group showed better OS (HR 0.52, 95% CI 0.27 to 0.99, P = .049) and NRM (HR 0.034, 95% CI 0.11 to 0.92, P = .034). No significant differences were observed in OS and NRM between the FB4-TBI and FB4 groups. The present study demonstrated that the FB4 plus low-dose ATG regimen improved OS and NRM, but FB4 plus low-dose TBI regimen had no clear benefit over FB4 alone, in MDS patients who used unrelated donors.

361.3: Revised Siplizumab-based conditioning regimen for combined kidney and bone marrow transplantation improved mixed hematopoietic chimerism with significant enrichment of regulatory T cells.

361.3: Revised Siplizumab-based conditioning regimen for combined kidney and bone marrow transplantation improved mixed hematopoietic chimerism with significant enrichment of regulatory T cells.

Targeting CDC42 reduces skeletal degeneration after hematopoietic stem cell transplantation

AbstractOsteopenia and osteoporosis are common long-term complications of the cytotoxic conditioning regimen for hematopoietic stem cell transplantation (HSCT). We examined mesenchymal stem and progenitor cells (MSPCs), which include skeletal progenitors, from mice undergoing HSCT. Such MSPCs showed reduced fibroblastic colony-forming units frequency, increased DNA damage, and enhanced occurrence of cellular senescence, whereas there was a reduced bone volume in animals that underwent HSCT. This reduced MSPC function correlated with elevated activation of the small Rho guanosine triphosphate hydrolase CDC42, disorganized F-actin distribution, mitochondrial abnormalities, and impaired mitophagy in MSPCs. Changes and defects similar to those in mice were also observed in MSPCs from humans undergoing HSCT. A pharmacological treatment that attenuated the elevated activation of CDC42 restored F-actin fiber alignment, mitochondrial function, and mitophagy in MSPCs in vitro. Finally, targeting CDC42 activity in vivo in animals undergoing transplants improved MSPC quality to increase both bone volume and trabecular bone thickness. Our study shows that attenuation of CDC42 activity is sufficient to attenuate reduced function of MSPCs in a BM transplant setting.

Antiemetic prophylaxis regimens in haematologic malignancies patients undergoing a hematopoietic stem cell transplantation. Which is the best standard of care? A systematic review.

This systematic review, adhering to PRISMA guidelines, aimed to evaluate the efficacy and safety of antiemetic prophylaxis in haematological patients undergoing high-dose chemotherapy as part of their hematopoietic stem cell transplantation (HSCT) conditioning regimens. We performed a comprehensive search in PubMed, EMBASE, ClinicalTrials.gov and the Cochrane database to identify randomised controlled trials (RCTs) and systematic reviews of antiemetic prophylaxis. Studies in English, French, Italian or Spanish were included. This review is registered with PROSPERO, ID CRD42023406380. Eight RCTs were analysed. The antiemetic regimens evaluated ranged from monotherapy with 5-Hydroxytryptamine Receptor 3 antagonists (5-HT3RAs) to complex combinations including olanzapine, neurokinin-1 receptor antagonists, 5-HT3RAs and corticosteroids. Complete response rates for triplet or quadruple regimens varied between 23.5% and 81.9%. Although no significant adverse effects were observed, minor symptoms such as diarrhoea, constipation, sedation and headaches were reported. Existing evidence on HSCT antiemetic therapy highlights its benefits but fails to provide clear clinical directions. The choice between triplet and quadruplet therapies for different patient scenarios is still uncertain. Until more detailed research is available, healthcare providers must rely on the latest guidelines and their judgement to customise antiemetic care for each patient's specific needs and risks.

Cyclophosphamide and horse anti-thymocyte globulin versus fludarabine, reduced cyclophosphamide and rabbit anti-thymocyte globulin conditioning regimen for allogeneic hematopoietic stem cell transplantation from matched sibling donors in patients with acquired aplastic anemia

ABSTRACT Background Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a potentially curative treatment for acquired aplastic anemia (acquired AA) in young patients. The objective of the study was to compare patient outcomes after Cyclophosphamide and horse antithymocyte globulin (Cy-hATG) versus Fludarabine-cyclophosphamide and rabbit ATG (Flu-Cy-rATG) as part of conditioning regimen in allo-HSCT for acquired AA. Research design and methods Descriptive retrospective study conducted on patients with acquired AA who received allo-HSCT from HLA-matched sibling donors between January 2008 and August 2022 after conditioning regimen with Cy-hATG or Flu-Cy-rATG. Results A total of 121 patients were enrolled. Cumulative incidence of graft failure was 11.2% in Cy-hATG and 5.3% Flu-Cy-rATG group. There were no significant differences between the two groups in terms of acute GVHD, chronic GVHD, and transplant related mortality. Flu-Cy-rATG group was associated with significantly higher CMV and EBV reactivation(s) compared to Cy-hATG group (p = 0.008 and 0.035, respectively). After a median follow-up of 58 months, estimated overall survival, event-free survival, and graft rejection-free survival were not statistically different between the two groups. Conclusions In high-risk population, Flu-Cy-rATG is associated with comparable outcomes to Cy-hATG in allo-HSCT from MSD. However, it seems to be associated with significant risk of viral infections.

Evaluate the Efficacy of Myeloablative Conditioning Regimens for Allogeneic Hematopoietic Stem Cell Transplantation in Acute Myelogenous Leukemia at BTH, Vietnam.

Background: Busulfan plus cyclophosphamide (Bu/Cy) is considered one of the classical myeloablative conditioning regimens. However, its toxicity can significantly increase mortality rates. To reduce both acute and long-term complications after hematopoietic stem cell transplantation (HSCT), newer conditioning regimens are being investigated. The purposes of this study were to assess the efficacy and safety of busulfan plus cyclophosphamide (Bu/Cy) and busulfan plus fludarabine (Bu/Flu) conditioning regimen for allogeneic HSCT (allo-HSCT) in acute myelogenous leukemia (AML). Materials and Methods: We conducted a single-center, retrospective analysis of AML, both adults and children, who underwent either Bu/Cy or Bu/Flu conditioning regimen for allo-HSCT and received peripheral blood stem cell transplants from HLA-matched donors. Results: From 2005 - 2019, 49 AML patients receiving Bu/Cy and 21 receiving Bu/Flu were identified, meeting inclusion criteria. The two groups showed no significant differences in age, gender, disease status pre-transplant, the median time to neutrophil and platelet engraftment. Bu/Flu patients had a shorter duration of neutropenia (median 7 days vs 10 days, p = 0.001) and shorter duration of thrombocytopenia (median 10 days vs 15 days, p = 0.016) than Bu/Cy. No difference was observed in disease-free survival (DFS) and overall survival (OS) between the two groups. Both univariate and multivariate analyses showed that age, disease status pre-transplant, and chronic graft-versus-host disease (GvHD) are related to worse DFS and OS. Conclusion : With similar efficacy to Bu/Cy but faster neutrophil and platelet recovery time, Bu/Flu is suitable as a pre-HSCT conditioning regimen for patients with AML.

Fludarabine, busulfan, and melphalan conditioning regimen in allogeneic hematopoietic stem cell transplantation for adult patients with myeloid malignancies: A multicenter retrospective study.

Relapse remains the main cause of treatment failure in patients with myeloid malignancies even after allogeneic hematopoietic stem cell transplantation (allo-HSCT). We observed a particularly low incidence of relapse in patients prepared with fludarabine, busulfan and melphalan in our previous study and this multicenter retrospective analysis aimed to confirm the feasibility of the regimen and to identify the potential prognostic factors. This study was performed using registry data from adults patients with myeloid malignancies who underwent their first allo-HSCT following fludarabine(≥100mg/m2), busulfan (≥3.2mg/kg) and melphalan (≥100mg/m2) based conditioning at nine transplantation centers in China between Jan. 2020 and Mar. 2022. A total of 221 consecutive patients (AML n=171, MDS-IB-1 or 2 n=44, CMML n=6) with median age of 46 were enrolled in this study. The median follow-up was 507 days for survivors. The 2-year NRM, CIR, OS and DFS were 10.6%±2.2%, 14.8%±3.3%, 79.4%±3.7% and 74.6%±3.7%, respectively. In multivariate analyses, high HCT-CI (≥3) was the only independent factor for higher NRM [hazard ratio (HR), 2.96; 95% confidence interval (CI), 1.11 to 7.90; p=0.030] and ECOG score ≥2 was the only independent factor for inferior OS (HR, 2.43; 95%CI, 1.15 to 5.16; p=0.020) and DFS (HR, 2.12; 95%CI, 1.13 to 4.02; p=0.020). AML diagnosis and positive measurable residual disease (MRD) at transplantation were predictors for higher CIR (HR=7.92, 95%CI 1.05-60.03, p=0.045; HR=3.64, 95%CI 1.40-9.44, p=0.008; respectively), while post-transplantation cyclophosphamide based graft-versus-host disease prophylaxis was associated with lower CIR (HR=0.24 95%CI 0.11-0.54, p=0.001). The intensity of conditioning regimen did not impact CIR, NRM, DFS and OS. These results supported that double alkylating agents of busulfan and melphalan based conditioning regimens were associated with low relapse rate and acceptable NRM in adult patients with myeloid malignancies. The optimal dose remained to be confirmed by further prospective studies.

Reproductive Health Assessment and Reports of Fertility Counseling in Pediatric and Adolescent Patients with Sickle Cell Disease After Hematopoietic Cell Transplantation

Conditioning regimens for hematopoietic cell transplant (HCT) in patients with sickle cell disease (SCD) place patients at risk for reproductive health issues. The purpose of this study was to assess reproductive health and reports of fertility counseling in patients with SCD who received a transplant. This was a secondary analysis of gonadal hormone production, future infertility risk assessment, and parent-proxy/patient reports of fertility counseling in SCD transplant recipients who are currently pubertal and were enrolled in the Atlanta sites of the Sickle Cell Transplant Evaluation of Long-term and Late Effects Registry (STELLAR) between May 2017 and October 2023. Clinical information was abstracted from medical records and reproductive health survey data from the STELLAR database. Descriptive statistics were reported as median (interquartile range [IQR]) or percentages. There were 20 females and 12 males in the study population. Females were median (IQR) 19.6 (9.4) years old and males 20.8 (11.4) years old at the time of the study. Transplants most commonly occurred in the decade 2010 to 2019 at 10.7 (4.8) years old for females and 11.1 (4.1) years old for males. Most participants received bone marrow stem cells (95.0% females, 100.0% males) from matched sibling donors (90.0% females, 100.0% males). Participants received one of seven HCT conditioning regimens with cyclophosphamide equivalent doses ranging from 3388 to 9706 mg/m2. The majority of females (90.0%) had diminished ovarian reserve with low anti-Mullerian hormone levels, and 61.1% had premature ovarian insufficiency with two follicle-stimulating hormone levels (FSH) ≥40 mIU/mL post-HCT. All males had normal testosterone levels, but 63.6% had elevated FSH levels suggestive of impaired spermatogenesis post-HCT. Parent proxies (for patients <18 years old) and patients ≥18 years old completed surveys 9.0 years (5.2) and 7.9 years (9.3) since HCT in females and males respectively. Twenty-five percent of parent proxies and 45% of patients reported that they had not been informed by a healthcare provider of the risk of infertility post-transplant. There are high rates of gonadal dysfunction post-HCT, but many parent proxies and patients do not recall being told of the risk for future infertility. More effective methods of education are warranted to ensure SCD patients and their families clearly understand the risk for reproductive health issues post-HCT.

Prognostic factors impacting post-transplant outcomes in adult T-cell acute lymphoblastic leukemia: a registry-based study by the EBMT acute leukemia working party.

T-cell acute lymphoblastic leukemia (T-ALL) predominantly affects individuals in late childhood and young adulthood. Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a curative modality particularly in the setting of poor risk genetics and/or persistent minimal residual disease. Limited studies have directly explored the impact of patient- and transplant-related factors on post-transplant outcomes in T-ALL. Using a large dataset from the European Society for Blood and Marrow Transplantation registry, we identified 1907 adult T-ALL patients (70% male) who underwent their first allo-HSCT in first complete remission (CR1) from matched sibling donors (MSD; 45%), unrelated donors (UD; 43%) or haploidentical donors (12%) between 2010 and 2021. The median age at transplant was 33.4 years (18.1-75). The median follow up was 2.9 years. Most patients underwent total body irradiation (TBI)-based myeloablative conditioning (69%). The 2-year overall survival (OS) was 69.4%, and leukemia -free survival (LFS) was 62.1%. In multivariate analysis, advanced age at transplant negatively affected LFS (for each 10-year increment, HR = 1.11, p = 0.004), GVHD-free, relapse-free survival (GRFS) (HR = 1.06, p = 0.04), OS (HR = 1.12, p = 0.002), and non-relapse mortality (NRM) (HR = 1.23, p < 0.001). More recent years of allo-HSCT were associated with improved GFRS (For each 3-year increment, HR = 0.89, p < 0.001), OS (HR = 0.9, p = 0.02), and decreased NRM (HR = 0.82, p = 0.008). TBI improved LFS. (HR = 0.79, p = 0.02), GRFS (HR = 0.83, p = 0.04), and relapse incidence (RI) (HR = 0.65, p < 0.001). Female-to-male transplant negatively affected GRFS (HR = 1.21, p = 0.02) and OS (HR = 1.23, p = 0.048). In vivo T-cell depletion significantly improved GFRS (HR = 0.74, p < 0.001). This large study identified prognostic factors, such as age at transplant conditioning regimen, in influencing post-transplant in adult T-ALL patients undergoing allo-HSCT. Importantly, a significant improvement over time was noted. These findings hold great promise for new adapted treatment strategies and can serve as a benchmark for future studies in that setting.

Successful Treatment of Refractory or Relapsed Hepatoblastoma With Autologous Hematopoietic Stem Cell Transplantation in Children.

The standard-risk hepatoblastoma has a good prognosis in children; however, refractory or relapsed (R/R) hepatoblastoma has a poor prognosis and high mortality rate. This study aimed to demonstrate the efficacy of high-dose chemotherapy and autologous hematopoietic stem cell transplantation (HSCT) rescue in pediatric patients with R/R hepatoblastoma. We retrospectively analyzed 6 pediatric patients with R/R hepatoblastoma who underwent autologous HSCT. The MEC conditioning regimen was used for all patients, comprising melphalan 140mg/m 2 /day intravenously (IV) on day 7 and 70mg/m 2 on day 6, etoposide 200mg/m 2 IV on days 5 to 8, and carboplatin 400mg/m 2 IV on days 5 to 8. One patient received a TopoThioCarbo regimen, comprising topotecan 2mg/m 2 /day IV on days 4 to 8, thiotepa 300mg/m 2 /day IV on days 6 to 8, and carboplatin 500mg/m 2 /day IV on days 3 to 5, as the conditioning regimen for the first transplantation. This was followed by salvage chemotherapy for relapse, and the second transplantation was performed using MEC as the conditioning regimen. We report the retrospective results of 6 patients with a median age of 1.8 (range 0.4 to 10.2) years who had R/R hepatoblastoma and underwent autologous HSCT. The median follow-up period was 58 (range 28 to 113) months after diagnosis. The median stage at diagnosis was 2.0 (range 2 to 4). Two patients had lung metastases during diagnosis. The median initial alpha-fetoprotein level was 292,888 (range 28,831 to 2,406,942) ng/mL, and the median number of chemotherapy lines before autologous HSCT was 3.5 (range 2 to 7). The disease status before HSCT was complete remission (CR) for all patients. The engraftment rate was 100%. No treatment-related mortality was reported. The 3-year event-free survival and overall survival rates were 83.3% and 100%, respectively. One patient relapsed after the second HSCT and achieved CR after salvage chemotherapy. This study suggests autologous HSCT as an effective treatment in pediatric patients with R/R hepatoblastoma. Nevertheless, future large-scale prospective studies are warranted.

BeEAM vs. BEAM: evaluating conditioning regimens for autologous stem cell transplantation in patients with relapsed or refractory DLBCL.

To evaluate whether BeEAM is an alternative to BEAM for autologous stem cell transplantation (ASCT) in patients with relapsed or refractory diffuse large B-cell lymphoma (DLBCL). Data of 60 patients with relapsed or refractory DLBCL who underwent ASCT from January 2018 to June 2023 in our center, including 30 patients in the BeEAM group and 30 patients in the BEAM group, were retrospectively analyzed. The time to hematopoietic reconstitution, treatment-related adverse events, number of hospitalization days, hospitalization cost, and survival benefit were compared between the two groups. The clinical characteristics of the patients did not significantly differ between the two groups. The median number of reinfused CD34 + cells was 5.06 × 106/kg and 5.17 × 106/kg in the BeEAM and BEAM groups, respectively, which did not significantly different (p = 0.8829). In the BeEAM and BEAM groups, the median time to neutrophil implantation was 10.2 and 10.27 days, respectively (p = 0.8253), and the median time to platelet implantation was 13.23 and 12.87 days, respectively (p = 0.7671). In the BeEAM and BEAM groups, the median hospitalization duration was 30.37 and 30.57 days, respectively (p = 0.9060), and the median hospitalization cost was RMB 83,425 and RMB 96,235, respectively (p = 0.0560). The hospitalization cost was lower in the BeEAM group. The most common hematologic adverse events were grade ≥ 3 neutropenia and thrombocytopenia, whose incidences were similar in the two groups. The most common non-hematologic adverse events were ≤ grade 2 and the incidences of these events did not significantly differ between the two groups. Median overall survival was not reached in either group, with predicted 5-year overall survival of 72.5% and 60% in the BeEAM and BEAM groups, respectively (p = 0.5872). Five-year progression-free survival was 25% and 20% in the BeEAM and BEAM groups, respectively (p = 0.6804). As a conditioning regimen for relapsed or refractory DLBCL, BeEAM has a desirable safety profile and is well tolerated, and its hematopoietic reconstitution time, number of hospitalization days, and survival benefit are not inferior to those of BEAM. BeEAM has a lower hospitalization cost and is an alternative to BEAM.

Effects of Total Body Irradiation on Hematopoietic Cell Transplantation Outcomes in Pediatric Acute Myeloid Leukemia with Prior Central Nervous System Involvement

The implications of previous central nervous system (CNS) involvement in children with acute myeloid leukemia (AML) undergoing hematopoietic cell transplantation (HCT) remain inadequately understood. Patients with CNS disease require more upfront CNS-directed intrathecal therapy, but little is known about whether transplant conditioning regimens should be intensified or if previous CNS involvement impacts post-HCT outcomes. While total body irradiation (TBI) remains standard for pediatric acute lymphoblastic leukemia myeloablative conditioning, it has been largely replaced with chemotherapy-only myeloablation in pediatric AML, primarily due to toxicity and late effects associated with TBI. In the setting of previous CNS involvement, it has been suggested that TBI-based myeloablation may have advantages due to superior CNS tissue penetration and thus decreased rates of AML relapse post-HCT. We analyzed a publicly available dataset derived from the Center for International Blood and Marrow Transplantation Research (CIBMTR) registry to characterize the impact of TBI in HCT preparative regimens in pediatric AML patients with a history of CNS involvement. The study dataset was obtained from the CIBMTR data repository. The study cohort included patients aged ≤21 years who underwent initial allogeneic HCT with myeloablative conditioning for de novo AML in the first or second complete remission (CR) between 2008 and 2016, who provided consent for research. Patients with mismatched related donor transplants and noncalcineurin inhibitor graft-versus-host disease (GVHD) prophylaxis were excluded. The dataset was further modified by excluding patients with missing disease site data or those with non-CNS extramedullary disease. Patients were categorized as CNS-positive or -negative AML (AML-CNS(+) and AML-CNS(-), respectively) based on the disease status at diagnosis. The Cox regression model and Fine-Grey methods were employed to delineate the effects of TBI and CNS disease on key HCT outcomes. The study cohort comprised 550 pediatric AML patients, of which 25% (n = 136) were AML-CNS(+). CNS involvement was more prevalent in patients aged 0 to 3 years, patients who were in the second CR, and those with a mismatched unrelated donor or umbilical cord blood. AML-CNS(+) patients demonstrated a lower relapse rate (hazard ratio: 0.50, 95% confidence interval: 0.33 to 0.76) compared to AML-CNS(-) patients, with comparable disease-free survival (DFS) and overall survival (OS) (P = .10 and 0.20, respectively) in the two cohorts. The entire TBI-treated cohort showed an association with increased risks of grade 2 to 4 acute GVHD, bloodstream infections, and endocrine dysfunction. TBI use within the AML-CNS(+) cohort was associated with a lower relapse rate but increased risks of nonrelapse mortality and a trend of higher grade 3 to 4 acute GVHD. In this population-based analysis of pediatric patients with de novo AML undergoing HCT, TBI-based conditioning regimens did not confer an advantage in DFS or OS compared to non-TBI regimens, irrespective of CNS disease status. However, TBI use was associated with increased risks of short- and long-term comorbidities. These findings underscore the need for careful consideration of TBI in pediatric AML.

Total body irradiation versus thiotepa/busulfan-based conditioning regimens for myeloablative allogeneic stem cell transplantation in adults with acute lymphoblastic leukemia.

Total body irradiation (TBI)-based conditioning regimens are generally recommended for allogeneic HSCT (allo-HSCT) in patients with acute lymphoblastic leukemia (ALL). Recent evidence suggests that modern chemotherapy-based regimens may be as effective. This multicenter retrospective study compared the clinical outcomes of myeloablative allo-HSCT with thiotepa, busulfan, and cyclophosphamide/fludarabine (TTB) to TBI-based conditioning. Between 2002 to 2018, 63 and 114 patients received TTB- and TBI-based conditioning regimens, respectively. The 5-year cumulative incidence of relapse was lower in the TBI cohort compared to the TTB cohort (30% [95% CI, 22-38] versus 47% [95% CI, 36-59]; P = 0.03). Multivariate analysis identified T-ALL, Ph-negative B-ALL, and measurable residual disease associated with a higher relapse risk. The 5-year cumulative incidence of non-relapsed mortality (NRM) was significantly lower with TTB (12% [95% CI, 5-20]) compared to TBI (25% [95% CI, 18-33]) (P = 0.001). Multivariate analysis found TBI conditioning, older age, and advanced stages of ALL at transplantation associated with a higher NRM. No statistical difference was seen in overall survival (49% [95% CI, 40-58] and 46% [95% CI, 35-60]) in the TBI and TTB groups, respectively; P = 0.9). The study suggests that TTB-based conditioning may be a promising option for ALL patients undergoing allo-HSCT, as it resulted in similar OS and lower NRM than TBI-based conditioning.

Impact of prophylactic echinocandin on the development of neurological complications in patients receiving busulfan-containing conditioning regimens for stem cell transplantation: A single-center retrospective study.

Although neurotoxicity is a major adverse event associated with busulfan, little information is available regarding the association between drug interactions and neurological symptoms during busulfan-based regimens. This study evaluated the association between prophylactic echinocandins and neurological complications in patients receiving busulfan-containing conditioning regimens for stem cell transplantation. We retrospectively included consecutive patients who administered intravenous busulfan as a conditioning regimen at our facility between 2007 and 2022. Prophylactic echinocandin use was defined as the use of an echinocandin antifungal drug to prevent invasive fungal disease in SCT recipients. The primary outcome was the incidence of neurological complications within 7 days of busulfan initiation and was compared between the echinocandin group (patients received prophylactic echinocandin) and nonechinocandin group (patients received prophylactic antifungal drugs other than echinocandin and those without antifungal prophylaxis). Among the 59 patients included in this study, the incidence of neurological complications in the echinocandin (n = 26) and nonechinocandin groups (n = 33) was 30.8% and 63.6%, respectively. We observed a negative association between prophylactic echinocandin use and the development of neurological complications after adjusting for the propensity score for receiving prophylactic echinocandins (adjusted odds ratio 0.294, 95% confidence interval 0.090 to 0.959). We observed a lower incidence of neurological complications in the echinocandin group than in the nonechinocandin group. Our results suggested that the choice of antifungal prophylaxis is associated with busulfan neurotoxicity.

High dose total marrow irradiation (TMI) does not increase long-term toxicity of myeloablative fludarabine/busulfan (FluBu4) conditioning regimen in allogeneic hematopoietic stem cell transplantation (HSCT).

Based on a previous phase 1 study, total marrow irradiation (TMI) at 9Gy was added to a myeloablative FluBu4 conditioning regimen in allogeneic hematopoietic stem cell transplantation (HSCT) for myeloid malignancies. Here, we report on the long-term toxicity of TMI combined with FluBu4 and compare it to patients who received only FluBu4. We retrospectively analyzed 38 consecutive patients conditioned with FluBu4/TMI (n = 15) or FluBu4 (n = 23, control group) who had at least 1 year follow-up post-transplant. The rate of long-term adverse events that have been previously associated with total body irradiation (TBI) was analyzed in the two groups. The baseline characteristics did not differ between the two groups. The control group had a longer median follow-up (71.2 mo) than the TMI group (38.5 mo) (p = .004). The most common adverse events were xerostomia, dental complications, cataracts, or osteopenia and did not differ between the two groups. Cognitive dysfunction or noninfectious pneumonitis, often detected after high dose TBI, were also not different in the two groups (p = .12 and p = .7, respectively). There was no grade 4 adverse event. Our results suggest that a conditioning regimen with TMI 9Gy and FluBu4 does not increase long-term adverse events after allogeneic HSCT.

Safety and efficacy of chimeric antigen receptor T-cell therapy for acute myeloid leukemia: A subgroup based meta-analysis

IntroductionAcute myeloid leukemia (AML) is a significant hematological malignancy in the United States, with a high mortality rate and limited treatment options. CAR T-cell therapy, a new and promising treatment, is being investigated for its efficacy and safety in AML. This meta-analysis aims to assess the safety and efficacy of CAR T-cell therapy in AML, considering various subgroups such as study location, study design, prior transplantation status, conditioning regimen, and CAR T-cell source. MethodsWe conducted a comprehensive literature review across multiple databases, adhering to PRISMA guidelines and focusing on studies concerning CAR T-cell therapy in AML. We included original articles in English and excluded non-original reviews, abstracts, and non-English studies. The risk of bias was assessed using the Cochrane ROBINS-I tool. Statistical analysis involved meta-analysis with Cochrane’s Q-test and I² statistic, using both fixed-effect and random-effects models, and assessed for publication bias. ResultsOur search yielded studies encompassing 57 AML patients treated with CAR T-cell therapy. The meta-analysis revealed a 48% incidence of complete remission with CAR T-cell therapy, varying significantly across subgroups based on study design, location, prior transplantation, conditioning regimen, and CAR T-cell source. The highest complete remission rates were observed in patients from China, those who had undergone prior hematopoietic cell transplantation, and those treated with fludarabine and cyclophosphamide conditioning regimen. Adverse events included graft-versus-host disease (7%) and cytokine release syndrome (53%). ConclusionsThis meta-analysis highlights the potential of CAR T-cell therapy in AML treatment, especially when integrated with certain prior treatments and conditioning regimens. The findings suggest a higher efficacy in patients with previous hematopoietic cell transplantation and specific conditioning regimens. Further large-scale, randomized trials are essential to confirm these findings and establish CAR T-cell therapy as a standard treatment for AML.

Autologous hematopoietic stem cell transplantation conditioning regimens and chimeric antigen receptor T cell therapy in various diseases.

Conditioning regimens employed in autologous stem cell transplantation have been proven useful in various hematological disorders and underlying malig nancies; however, despite being efficacious in various instances, negative consequences have also been recorded. Multiple conditioning regimens were extracted from various literature searches from databases like PubMed, Google scholar, EMBASE, and Cochrane. Conditioning regimens for each disease were compared by using various end points such as overall survival (OS), progression free survival (PFS), and leukemia free survival (LFS). Variables were presented on graphs and analyzed to conclude a more efficacious conditioning regimen. In multiple myeloma, the most effective regimen was high dose melphalan (MEL) given at a dose of 200/mg/m2. The comparative results of acute myeloid leukemia were presented and the regimens that proved to be at an admirable position were busulfan (BU) + MEL regarding OS and BU + VP16 regarding LFS. In case of acute lymphoblastic leukemia (ALL), BU, fludarabine, and etoposide (BuFluVP) conferred good disease control not only with a paramount improvement in survival rate but also low risk of recurrence. However, for ALL, chimeric antigen receptor (CAR) T cell therapy was preferred in the context of better OS and LFS. With respect to Hodgkin's lymphoma, mitoxantrone (MITO)/MEL overtook carmustine, VP16, cytarabine, and MEL in view of PFS and vice versa regarding OS. Non-Hodgkin's lymphoma patients were administered MITO (60 mg/m2) and MEL (180 mg/m2) which showed promising results. Lastly, amyloidosis was considered, and the regimen that proved to be competent was MEL 200 (200 mg/m2). This review article demonstrates a comparison between various conditioning regimens employed in different diseases.

Impact of Different Fludarabine Doses in the Fludarabine-Based Conditioning Regimen for Unrelated Bone Marrow Transplantation

The purine analog fludarabine (Flu) plays a central role in reduced-intensity conditioning and myeloablative reduced-toxicity conditioning regimens because of limited nonhematologic toxicities. Few reports assess the impact of different dose of Flu on the clinical outcomes and the Flu doses vary across reports. To compare the effect of Flu dose, the clinical outcomes of patients who received Flu and busulfan (FB; n = 1647) or melphalan (Flu with melphalan (FM); n = 1162) conditioning for unrelated bone marrow transplantation were retrospectively analyzed using Japanese nationwide registry data. In the FB group, high-dose Flu (180 mg/m2; HFB) and low-dose Flu (150/125 mg/m2; LFB) were given to 1334 and 313 patients, respectively. The 3-year overall survival (OS) rates were significantly higher in the HFB group than in the LFB group (49.5% versus 39.2%, P < .001). In the HFB and LFB groups, the cumulative incidences were 30.4% and 36.6% (P = .058) for 3-year relapse and 25.1% and 28.1% (P = .24) for 3-year nonrelapse mortality (NRM), respectively. In the multivariate analysis for OS and relapse, Flu dose was identified as an independent prognostic factor (hazard ratio: 0.83, P = .03; hazard ratio: 0.80, P = .043). In the FM group, high-dose Flu (180 mg/m2; HFM) and low-dose Flu (150/125 mg/m2; LFM) were given to 118 and 1044 patients, respectively. The OS, relapse, and NRM after 3 years did not differ significantly between the HFM and LFM groups (48.3% versus 48.8%, P = .92; 23.7% versus 27.2%, P = .55; 31.9% versus 30.8%, P = .67). These findings suggest that high-dose Flu was associated with favorable outcomes in the FB group but not in the FM group.

Clofarabine and High-Dose Melphalan Reduced Intensity Conditioning Regimen for Allogeneic Stem Cell Transplantation

Clofarabine and High-Dose Melphalan Reduced Intensity Conditioning Regimen for Allogeneic Stem Cell Transplantation

Evolution of dosimetric treatment planning for pediatric total lymphoid irradiation (TLI): a single-institution experience.

Total lymphoid irradiation (TLI) is a conditioning regimen in allogeneic hematopoietic stem cell transplantation (allo-HSCT) which may reduce long-term toxicities attributed to other techniques, such as total body irradiation (TBI). At our institution, TLI treatments were first planned with the three-dimensional conformal radiation therapy (3D-CRT) technique and later with volumetric modulated arc therapy (VMAT). With the recent availability of a basic helical tomotherapy (HT), the possible dosimetric gain of the latter for TLI is studied. 22 pediatric patients were planned for VMAT and HT, prescribed to 8 Gy in 4 fractions. VMAT was planned with template based on a single cost function, using the Monaco treatment planning system (TPS). HT plans were planned using Accuray Precision TPS for a basic HT without the dynamic jaws feature or VOLO-Ultra algorithm. Plan quality was analyzed based on four quality indices, mean and maximum doses to planning target volume (PTV) and organs at risk (OARs), dose gradient and integral doses. Differences were analyzed with Wilcoxon signed-rank test. HT plans resulted in improved conformity (CI) and homogeneity indices (HI) (p < 0.05) but less steep dose gradient (p = 0.181). VMAT plans created larger areas with high doses within the PTV, while comparable doses to OARs, except mainly for the spinal marrow, for which a reduction of 37.7% in D2% was obtained (p < 0.05). Integral dose for non-tumor tissue was 11.3% lower with the VMAT template (p < 0.05). HT achieves better conformity and homogeneity even without its more advanced features. Nevertheless, the VMAT template achieves dosimetric results close to those of HT, both with similar clinical outcome.