Conditioning chemotherapy dose adjustment in obese patients: a review and position statement by the American Society for Blood and Marrow Transplantation practice guideline committee

Clinical and safety outcomes of BeEAM (Bendamustine, Etoposide, Cytarabine, Melphalan) versus CEM (Carboplatin, Etoposide, Melphalan) in lymphoma patients as a conditioning regimen before autologous hematopoietic cell transplantation

BACKGROUND

Autologous stem cell transplantation (ASCT) is a pivotal treatment for lymphoma patients. The BeEAM regimen (Bendamustine, Etoposide, Cytarabine, Melphalan) traditionally relies on cryopreservation, whereas the CEM regimen (Carboplatin, Etoposide, Melphalan) has been optimized for short-duration administration without the need for cryopreservation. This study rigorously compares the clinical and safety profiles of the BeEAM and CEM regimens.

METHODS

A controlled, randomized clinical trial was conducted with 58 lymphoma patients undergoing ASCT at the International Medical Center (IMC) in Cairo, Egypt. Patients were randomly assigned to either the BeEAM (n = 29) or CEM (n = 29) regimen, with an 18-month follow-up period. Clinical and safety outcomes were meticulously compared, focusing on time to engraftment for neutrophils and platelets, side effects, length of hospitalization, transplant-related mortality (TRM), and survival rates.

RESULTS

The findings demonstrate a significant advantage for the CEM regimen. Neutrophil recovery was markedly faster in the CEM group, averaging 8.5 days compared to 14.5 days in the BeEAM group (p < 0.0001). Platelet recovery was similarly expedited, with 11 days in the CEM group versus 23 days in the BeEAM group (p < 0.0001). Hospitalization duration was substantially shorter for CEM patients, averaging 18.5 days compared to 30 days for those on BeEAM (p < 0.0001). Furthermore, overall survival (OS) was significantly higher in the CEM group at 96.55% (95% CI: 84.91-99.44%) compared to 79.31% (95% CI: 63.11-89.75%) in the BeEAM group (p = 0.049). Progression-free survival (PFS) was also notably superior in the CEM group, at 86.21% (95% CI: 86.14-86.28%) versus 62.07% (95% CI: 61.94-62.20%) in the BeEAM group (p = 0.036).

CONCLUSION

The CEM regimen might demonstrate superiority over the BeEAM regimen, with faster neutrophil and platelet recovery, reduced hospitalization time, and significantly improved overall and progression-free survival rates. Future studies with longer duration and larger sample sizes are warranted.

TRIAL REGISTRATION

This study is registered on ClinicalTrials.gov under the registration number NCT05813132 ( https://clinicaltrials.gov/ct2/show/NCT05813132 ). (The first submitted registration date: is March 16, 2023).

[An online tool to personalize the drug-doses for obese adults]

BACKGROUND

Between 1975 and 2014, the number of people suffering from obesity tripled, reaching 17% of the adult population in France and more than 35% in the United States. Obesity is defined by a Body Mass Index (BMI)>30kg/m2 and characterized by a significant accumulation of adipose tissue responsible for the increase in weight. This accumulation leads to physiological changes capable of modifying the pharmacokinetics of drugs, which can lead to the administration of inappropriate doses. For this reason, some significant dosage adjustments are necessary for obese patients. However, data on these adaptations are not easily accessible and sometimes complex to implement in practice.

AIM

To perform a new online tool allowing to calculate and propose an adjusted dose of a drug that should be administered to an obese patient.

METHOD

(i) carrying out an extensive bibliographic research according to the PRISMA methodology; and (ii) the development of a new website site proposing an adjusted dose for obese patients.

RESULTS

Firstly, 49 reviews concerning the dose adaptation have been evaluated and, secondly, 319 articles have been selected. Among them, 204 articles have been included in the database to justify the adjusted dose of 84 drugs and administration methods including antibiotics, antifungals, anticoagulants or even cancer drugs. This database is available online through a calculator on the website named Adapt'Obese. Thus, with the sex, height and weight of an obese patient, Adapt'Obese proposes a personalized and adjusted dose of the drug to administer.

PERSPECTIVES

Other drugs will be added soon, and functional improvements are planned, with the aim of adapting the dosages in obese patients, as for patients with renal insufficiency.

Optimizing high dose melphalan

Melphalan, has been a major component of myeloma therapy since the 1950s. In the context of hematopoietic cell transplantation (HCT), high dose melphalan (HDM) is the most common conditioning regimen used due to its potent anti-myeloma effects and manageable toxicities. Common toxicities associated with HDM include myelosuppression, gastrointestinal issues, and mucositis. Established approaches to reduce these toxicities encompass dose modification, nausea prophylaxis with 5HT3 receptor antagonists, cryotherapy, amifostine use, and growth factors. Optimization of melphalan exposure through personalized dosing and its combination with other agents like busulfan, or bendamustine show promise. Propylene glycol-free melphalan (Evomela) represents a novel formulation aiming to enhance drug stability and reduce adverse effects. This review explores strategies to enhance the efficacy and mitigate the toxicity of HDM in multiple myeloma. Future directions involve exploring these strategies in clinical trials to improve the safety and efficacy of HDM, thereby enhancing outcomes for multiple myeloma patients undergoing autologous HCT.

Pharmacokinetic Modeling and Simulation with Pharmacogenetic Insights Support the Relevance of Therapeutic Drug Monitoring for Myeloablative Busulfan Dosing in Adult HSCT

Therapeutic drug monitoring (TDM) of busulfan (Bu) is well-established in pediatric hematopoietic stem cell transplantation (HSCT), but its use in adults is limited due to a lack of clear recommendations and scarcity of evidence regarding its utility. GSTA1 promoter variants are reported to affect Bu clearance in both adults and pediatric patients. This study aimed to evaluate the value of preemptive genotyping GSTA1 and body composition (obesity) in individualizing Bu dosing in adults, through pharmacokinetic (PK) modeling and simulations. A population pharmacokinetic (PopPK) model was developed and validated with data from 60 adults who underwent HSCT. Simulations assessed different dosing scenarios based on body size metrics and GSTA1 genotypes. Due to the limited number of obese patients in the cohort, the effect of obesity on Bu pharmacokinetics (PK) was evaluated in silico using a physiologically-based pharmacokinetic (PBPK) model and relevant virtual populations from Simcyp software. Patients with at least 1 GSTA1*B haplotype had 17% lower clearance on average. PopPK simulations indicated that adjusting doses based on genotype increased the probability of achieving the target exposure (3.7 to 5.5 mg.h/L) from 53% to 60 % in GSTA1*A homozygous patients, and from 50% to 61% in *B carriers. Still, Approximately 40% of patients would not achieve this therapeutic window without TDM. A 2-sample optimal design was validated for routine model-based Bu first dose AUC0-∞ estimation, and the model was implemented in the Tucuxi user-friendly TDM software. PBPK simulations confirmed body surface area-based doses of 29 to 31 mg/m2/6h as the most appropriate, regardless of obesity status. This study emphasizes the importance of individualized Bu dosing strategies in adults to achieve therapeutic targets. Preemptive genotyping alone may not have a significant clinical impact, and routine TDM may be necessary for optimal transplantation outcomes.

Clinical presentation of cardiac symptoms following treatment with tumor-infiltrating lymphocytes: diagnostic challenges and lessons learned

BACKGROUND

Treatment with tumor-infiltrating lymphocytes (TILs) is rapidly evolving for patients with solid tumors. Following metastasectomy, TILs (autologous, intratumoral CD4+ and CD8+ T cells with the potential to recognize tumor-associated antigens) are isolated and non-specifically expanded ex vivo in the presence of interleukin-2 (IL-2). Subsequently, the TILs are adoptively transferred to the patients after a preconditioning non-myeloablative, lymphodepleting chemotherapy regimen, followed by administration of high-dose (HD) IL-2. Here, we provide an overview of known cardiac risks associated with TIL treatment and report on seven patients presenting with cardiac symptoms, all with different clinical course and diagnostic findings during treatment with lymphodepleting chemotherapy, TIL, and HD IL-2, and propose a set of clinical recommendations for diagnosis and management of these symptoms.

PATIENTS AND METHODS

This single-center, retrospective study included selected patients who experienced TIL treatment-related cardiac symptoms at the Netherlands Cancer Institute. In addition, 12 patients were included who received TIL in the clinical trial setting without experiencing cardiac symptoms, from whom complete cardiac biomarker follow-up during treatment was available [creatine kinase (CK), CK-myocardial band, troponin T and N-terminal pro-B-type natriuretic peptide].

RESULTS

Within our TIL patient population, seven illustrative cases were chosen from the patients who developed symptoms suspected of severe cardiotoxicity: myocarditis, myocardial infarction, peri-myocarditis, atrial fibrillation, acute dyspnea, and two cases of heart failure. An overview of their clinical course, diagnostics carried out, and management of the symptoms is provided.

CONCLUSIONS

In the absence of evidence-based guidelines for the treatment of TIL therapy-associated cardiotoxicity, we provided an overview of literature, case descriptions, and recommendations for diagnosis and management to help physicians in daily practice, as the number of patients qualifying for TIL treatment is rapidly increasing.

Population Pharmacokinetic Model of Intravenous Busulfan in Hematopoietic Cell Transplantation: Systematic Review and Comparative Simulations

BACKGROUND

Busulfan is commonly used in the chemotherapy prior to hematopoietic cell transplantation (HCT). Busulfan has a narrow therapeutic window and a well-established exposure-response relationship with important clinical outcomes. Model-informed precision dosing (MIPD) based on population pharmacokinetic (popPK) models has been implemented in the clinical settings. We aimed to systematically review existing literature on popPK models of intravenous busulfan.

METHODS

We systematically searched Ovid MEDLINE, EMBASE, Cochrane Library, Scopus, and Web of Science databases from inception to December 2022 to identify original popPK models (nonlinear mixed-effect modeling) of intravenous busulfan in HCT population. Model-predicted busulfan clearance (CL) was compared using US population data.

RESULTS

Of the 44 eligible popPK studies published since 2002, 68% were developed predominantly in children, 20% in adults, and 11% in both children and adults. The majority of the models were described using first-order elimination or time-varying CL (69% and 26%, respectively). All but three included a body-size descriptor (e.g., body weight, body surface area). Other commonly included covariates were age (30%) and GSTA1 variant (15%). Median between-subject and between-occasion variabilities of CL were 20% and 11%, respectively. Between-model variabilities in predicted median CL were < 20% in all of the weight tiers (10-110 kg) in the simulation based on US population data.

CONCLUSION

Busulfan PK is commonly described using a first-order elimination or time-varying CL. A simple model with limited covariates were generally sufficient to attain relatively small unexplained variabilities. However, therapeutic drug monitoring may still be necessary to attain a narrow target exposure.

Cardiotoxicity in autologous haematopoietic stem cell transplantation for systemic sclerosis

Autologous haematopoietic stem cell transplantation is now well-established as an effective treatment for severe systemic sclerosis with clear demonstration of favourable end-organ and survival outcomes. Treatment-related cardiotoxicity remains the predominant safety concern and contraindicates autologous haematopoietic stem cell transplantation in patients with severe cardiopulmonary disease. In this review, we describe the cardiovascular outcomes of autologous haematopoietic stem cell transplantation recipients, discuss the potential mechanisms of cardiotoxicity and propose future mitigating strategies.

Evaluation of Children with Malignancies for Blood and Marrow Transplantation: A Report from the ASTCT Committee on Practice Guidelines

Evaluation of a candidate for hematopoietic cell transplantation (HCT) is a complex process with substantial intercenter variability. Although literature providing guidance for evaluating the eligibility of adults is well established, similar guidance for children is lacking. To address gaps between adult recommendations and the specific needs of children, we convened a panel of pediatric HCT experts from a wide geographic range of American Society of Transplantation and Cellular Therapy (ASTCT) member institutions to offer recommendations for pediatric-focused pre-HCT evaluation. In this report from the ASTCT Committee on Practice Guidelines, we present a practical framework for evaluating children with malignancies who are candidates for HCT. We also highlight key differences from adults and emphasize areas of unmet need that require additional research to delineate best practices.

Individualizing busulfan dose in specific populations and evaluating the risk of pharmacokinetic drug-drug interactions

INTRODUCTION

Busulfan is an alkylating agent widely used in the conditioning of hematopoietic stem cell transplantation possessing a complex metabolism and a large interindividual and intra-individual variability, especially in children. Combined with the strong rationale of busulfan PK/PD relationships, factors altering its clearance (e.g., weight, age, and GST-A genetic polymorphism mainly) can also affect clinical outcomes.

AREAS COVERED

This review aims to provide an overview of the current knowledge on busulfan pharmacokinetics, its pharmacokinetics variabilities in pediatric populations, drug-drug interactions (DDI), and their consequences regarding dose individualization. This review was based on medical literature up until October 2021.

EXPERT OPINION

To ensure effective busulfan exposure in pediatrics, different weight-based nomograms have been established to determine busulfan dosage and provided improved results (65 - 80% of patients correctly exposed). In addition to nomograms, therapeutic drug monitoring (TDM) of busulfan measuring plasmatic concentrations to estimate busulfan pharmacokinetic parameters can be used. TDM is now widely carried out in routine practices and aims to ensure the targeting of the reported therapeutic windows by individualizing busulfan dosing based on the clearance estimations from a previous dose.

Impact of the insertion of the clinical pharmacist in the Allogeneic Hematopoietic Stem Cells Transplantation team

INTRODUCTION

Allogeneic Hematopoietic Stem Cells Transplantation (allo-HSCT) is capable of curing patients with neoplastic or non-neoplastic hematologic disorders or of prolonging their survival. This study assessed if the insertion of the clinical pharmacist in the allo-HSCT team modified the outcomes: transplantation-related mortality, grafting failure, incidence of Graft versus Host Disease, hospitalization time, time for grafting, number of readmissions, number of drug-related problems (DRPs), adherence and knowledge about pharmacotherapy.

METHODS

Interventional study with historical control carried out in an allo-HSCT unit, in which the intervention group (IG) included 33 individuals who received pharmacotherapy follow-up. Control Group (CG) consisted of 28 individuals.

RESULTS

A total of 250 DRPs were identified, 59 team's doubts were clarified, and 309 interventions were conducted in the IG. The DRPs mainly arose from safety (51.60%) and effectiveness (38.40%) problems. A mean of 9.36 (SD = 6.97) interventions per patient was obtained, mainly including dose reductions (19.09%), adjustments in administration time (18.12%), educational activities (15.21%) and drug removal (10.68%). Clinical significance of the interventions was considered high (75.7% extremely significant, very significant or significant), as well as their acceptability (89.7% accepted). Each patient attended a mean of 4.68 pharmaceutical consultations (SD = 1.91) after hospital discharge, presenting increase in knowledge (p = 0.0001) and in adherence (p = 0.0115). There was no evidence of differences between the groups in the other outcomes analyzed.

CONCLUSIONS

The pharmacotherapy follow-up allowed detecting several DRPs and performing interventions of high clinical relevance and acceptability, in addition to improving adherence and individualizing the pharmacotherapy.

NCCN Guidelines® Insights: Hematopoietic Cell Transplantation, Version 3.2022

The NCCN Guidelines for Hematopoietic Cell Transplantation (HCT) provide an evidence- and consensus-based approach for the use of autologous and allogeneic HCT in the management of malignant diseases in adult patients. HCT is a potentially curative treatment option for patients with certain types of malignancies; however, recurrent malignancy and transplant-related complications often limit the long-term survival of HCT recipients. The purpose of these guidelines is to provide guidance regarding aspects of HCT, including pretransplant recipient evaluation, hematopoietic cell mobilization, and treatment of graft-versus-host disease-a major complication of allogeneic HCT-to enable the patient and clinician to assess management options in the context of an individual patient's condition. These NCCN Guidelines Insights provide a summary of the important recent updates to the NCCN Guidelines for HCT, including the incorporation of a newly developed section on the Principles of Conditioning for HCT.

Comparison of Dose Adjustment Strategies for Obesity in High-dose Cyclophosphamide Among Adult Hematopoietic Cell Transplantation Recipients: Pharmacokinetic Analysis

Cyclophosphamide (CY) is an alkylating agent widely used in the field of oncology and hematopoietic cell transplantation (HCT). It is recommended to use an adjusted body weight with an adjustment factor of 0.25 (ABW25) for dosing of CY in obese patients undergoing HCT. However, evidence based on the pharmacokinetics (PK) of CY to support this recommendation is lacking. We aimed to identify a dosing strategy of CY that achieves equivalent exposures among obese and nonobese patients. The present study is a secondary analysis of a previously conducted observational PK study of phosphoramide mustard (PM), the final cytotoxic metabolite of CY. Data were collected from 85 adults with hematologic malignancy who received a single infusion of CY 50 mg/kg, fludarabine, ± anti-thymocyte globulin, and a single fraction of total body irradiation as HCT conditioning therapy. A previously developed population PK model in these patients was used for simulations. Using individualized PK parameters from that analysis, simulations were performed to assess cumulative exposures of PM (i.e., area-under-the-curve [AUC]) resulting from 8 different dosing strategies according to various measures of body size: (1) "mg/kg" by total body weight (TBW); (2) "mg/kg" by ideal body weight (IBW); (3) "mg/kg" by fat free mass; (4) "mg/m²" by body surface area (BSA); (5) "mg/kg" by TBW combined with ABW25 (TBW-ABW25); (6) "mg/kg" by IBW combined with ABW25 (IBW-ABW25); (7) "mg/kg" by TBW combined with ABW by adjustment factor of 0.50 (TBW-ABW50); and (8) "mg" by fixed-dose. We defined equivalent exposure as the effect of obesity on PM AUC within ±20% from the PM AUC in the nonobese group, where obesity is defined based on TBW/IBW ratio (i.e., nonobese, <1.2; mildly obese, 1.2-1.5; and moderately/severely obese, >1.5). Primary and secondary outcomes were PM AUC_0-8hours and PM AUC_0-infinity, respectively. In the 85 patients, with the median age of 63 years (range 21-75), 46% were classified as mildly and 25% were moderately/severely obese based on the TBW/IBW ratio. Negative correlations (i.e., higher the extent of obesity, lower the PM AUC) were shown when dosing simulations were based on IBW, TBW-ABW25, and fixed dosing (P < .05). Positive correlations were shown when dosing was simulated by TBW (P < .05). None of the 8 dosing strategies attained equivalent PM AUC_0-8hours between patients with versus without obesity, whereas dosing by BSA and TBW-ABW50 attained equivalent PM AUC_0-infinity (P < .05). Our study predicted that the recommended ABW25 dose adjustment may result in lower exposure of CY therapy in obese patients than in nonobese. A CY dosing strategy that would result in similar PM concentrations between obese and nonobese was not identified for early exposure (i.e., PM AUC_0-8hours). The data suggest though that CY dosing based on "mg/m²" by BSA or "mg/kg" by TBW-ABW50 would result in similar total exposure (i.e., PM AUC_0-infinity) and may minimize exposure differences in obese and nonobese patients.

Evaluation of Melphalan Exposure in Lymphoma Patients Undergoing BEAM and Autologous Hematopoietic Cell Transplantation

High-dose melphalan is one of the main cytotoxic DNA alkylating agents and is used in many transplantation conditioning regimens. Studies have shown a wide range of drug exposure when a traditional weight-based dose of melphalan is used. The optimal melphalan dose in BEAM (carmustine, etoposide, cytarabine, and melphalan), which results in maximum efficacy with acceptable toxicity, is unknown. In this pharmacokinetic (PK) analysis of 105 patients with lymphoma undergoing treatment with BEAM and autologous hematopoietic cell transplantation, we initially estimated melphalan exposure as area under the curve (AUC) by a noncompartmental analysis and subsequently compared it with a newly developed 2-compartment population-PK model. The 2 models correlated closely with each other. We found that the traditional fixed weight-based dosing of propylene glycol-free (captisol-enabled) melphalan in BEAM results in a wide variation in exposure as estimated by both models. Higher melphalan exposure was significantly associated with increased metabolic toxicities but did not seem to impact progression-free survival. Although our study suggests a melphalan AUC of 8 mg·h/L as a potential target in BEAM, larger prospective studies using personalized PK-directed melphalan dosing are needed to determine the optimal melphalan exposure in lymphomas.

External Evaluation of Population Pharmacokinetic Models of Busulfan in Chinese Adult Hematopoietic Stem Cell Transplantation Recipients

Objective: Busulfan (BU) is a bi-functional DNA-alkylating agent used in patients undergoing hematopoietic stem cell transplantation (HSCT). Over the last decades, several population pharmacokinetic (pop PK) models of BU have been established, but external evaluation has not been performed for almost all models. The purpose of the study was to evaluate the predictive performance of published pop PK models of intravenous BU in adults using an independent dataset from Chinese HSCT patients, and to identify the best model to guide personalized dosing.

Methods: The external evaluation methods included prediction-based diagnostics, simulation-based diagnostics, and Bayesian forecasting. In prediction-based diagnostics, the relative prediction error (PE%) was calculated by comparing the population predicted concentration (PRED) with the observations. Simulation-based diagnostics included the prediction- and variability-corrected visual predictive check (pvcVPC) and the normalized prediction distribution error (NPDE). Bayesian forecasting was executed by giving prior one to four observations. The factors influencing the model predictability, including the impact of structural models, were assessed.

Results: A total of 440 concentrations (110 patients) were obtained for analysis. Based on prediction-based diagnostics and Bayesian forecasting, preferable predictive performance was observed in the model developed by Huang et al. The median PE% was -1.44% which was closest to 0, and the maximum F₂₀ of 57.27% and F₃₀ of 72.73% were achieved. Bayesian forecasting demonstrated that prior concentrations remarkably improved the prediction precision and accuracy of all models, even with only one prior concentration.

Conclusion: This is the first study to comprehensively evaluate published pop PK models of BU. The model built by Huang et al. had satisfactory predictive performance, which can be used to guide individualized dosage adjustment of BU in Chinese patients.

Does recipient body mass index inform donor selection for allogeneic haematopoietic cell transplantation?

It is not known whether obesity has a differential effect on allogeneic haematopoietic cell transplantation outcomes with alternative donor types. We report the results of a retrospective registry study examining the effect of obesity [body mass index (BMI) > 30] on outcomes with alternative donors (haploidentical related donor with two or more mismatches and receiving post-transplant cyclophosphamide [haplo] and cord blood (CBU)] versus matched unrelated donor (MUD). Adult patients receiving haematopoietic cell transplantation for haematologic malignancy (2013-2017) (N = 16 182) using MUD (n = 11 801), haplo (n = 2894) and CBU (n = 1487) were included. The primary outcome was non-relapse mortality (NRM). The analysis demonstrated a significant, non-linear interaction between pretransplant BMI and the three donor groups for NRM: NRM risk was significantly higher with CBU compared to haplo at BMI 25-30 [hazard ratio (HR) 1.66-1.71, p < 0.05] and MUD transplants at a BMI of 25-45 (HR, 1.61-3.47, p < 0.05). The results demonstrated that NRM and survival outcomes are worse in overweight and obese transplant recipients (BMI ≥ 25) with one alternative donor type over MUD, although obesity does not appear to confer a uniform differential mortality risk with one donor type over the other. BMI may serve as a criterion for selecting a donor among the three (MUD, haplo and CBU) options, if matched sibling donor is not available.

A prospective study of filgrastim pharmacokinetics in morbidly obese patients compared with non-obese controls

INTRODUCTION

Filgrastim is a human granulocyte colony-stimulating factor (G-CSF). There are limited data on dosing filgrastim in obesity. The objective of this study was to compare filgrastim pharmacokinetic parameters for morbidly obese and non-obese patients after a single subcutaneous dose of filgrastim dosed per actual body weight.

METHODS

This prospective, matched-pair study (NCT01719432) included patients ≥18 years of age, receiving filgrastim at 5 μg/kg with a weight >190% of their ideal body weight (IBW) for "morbidly obese" patients or within 80%-124% of IBW for matched-control patients. The control group was prospectively matched for age (within 10 years), degree of neutropenia, and gender. Filgrastim doses were not rounded to vial size, to allow more accurate assessment of exposure. Blood samples were collected at 0 (prior to dose), 2, 4, 6, 8, 12, and 24 h after the first subcutaneous administration of filgrastim.

RESULTS

A total of 30 patients were enrolled in this prospective pharmacokinetic study, with 15 patients assigned to each arm. Non-compartmental analysis showed that the systemic clearance (Cl) was 0.111 ± 0.041 ml/min in the morbidly obese group versus 0.124 ± 0.045 ml/min in the non-obese group (p = 0.44). Additionally, the mean area under the curve (AUC_0-24h ) was 49.3 ± 13.9 ng/ml × min in the morbidly obese group versus 46.3 ± 16.8 ng/mL x min in the non-obese group (p = 0.6). No differences were seen in maximum concentrations (C_max ) between the two groups (morbidly obese: 48.1 ± 14.7 ng/ml vs. non-obese: 49.2 ± 20.7 ng/ml (p = 0.87)). The morbidly obese group had a numerically higher, but not statistically significant, increase in time to maximum concentration (T_max ) compared to the non-obese group (544 ± 145 min vs 436 ± 156 min (p = 0.06), respectively).

CONCLUSION

Calculating subcutaneous filgrastim doses using actual body weight appears to produce similar systemic exposure in morbidly obese and non-obese patients with severe neutropenia.

Beyond steroids: A systematic review and proposed solutions to managing acute graft-versus-host disease in adolescents and young adults

The outcomes of allogeneic hematopoietic cell transplantation (HCT) in adolescents and young adults (AYAs) with hematologic malignancies have been shown to be poorer when compared to results in children, due to a combination of higher relapse rates and greater treatment-related mortality (TRM). Although differences in relapse risk have been studied extensively, toxicity has been examined and reported less often. In this systematic review, we summarize recently published studies that have examined the differences in rates of TRM and acute graft-versus-host disease (GVHD) in AYAs and children with hematologic malignancies, and attempt to explain why these disparities exist and how they impact outcomes. In addition, we present best practices for management of steroid-refractory GVHD that are likely to improve survival in this patient population. Further, we propose the development of personalized, risk-based approaches for the prevention and treatment of GVHD that incorporate novel platforms and interventions. We believe this individualized approach is likely to reduce toxicity and greatly improve outcomes for this vulnerable population.

Body Surface Area Dosing of High-Dose Methotrexate Should Be Reconsidered, Particularly in Overweight, Adult Patients

BACKGROUND

High-dose methotrexate is used for treating several types of cancer. However, it is associated with a high risk of acute kidney injury (AKI), especially in patients with high MTX concentrations. Although therapeutic drug monitoring is performed to monitor MTX concentrations, it is unclear what concentration should be considered critical, thus requiring rescue protocols to prevent nephrotoxicity.

METHODS

Patients treated with high-dose methotrexate for lymphoma or acute lymphoblastic leukemia and those benefited from therapeutic drug monitoring were included. The relationship between MTX concentrations and the presence or absence of AKI was assessed. MTX concentrations were analyzed using a population pharmacokinetic approach. Specific attention was given to morphological covariates because MTX doses are individualized according to body surface area (BSA).

RESULTS

In total, 328 patients and 657 cycles of treatment were analyzed. Higher MTX concentrations were observed in the AKI+ group. For cycle 1, all patients showing an MTX concentration >6 µM at 36 hours or >2 µM at 48 hours after infusion developed nephrotoxicity. The final pharmacokinetic model had 2 compartments and included the effect of age on clearance (CL) and of body weight on peripheral distribution volume. None of the morphological covariates tested on CL led to significant improvement in the model. Higher MTX concentrations were observed in patients with extreme BSA values (≥2 m2) or body mass index (≥25 kg/m2). Patients with AKI who received at least 1 cycle had higher BSA and BMI.

CONCLUSIONS

The results from this study provide additional information on the relationship between MTX concentration and nephrotoxicity. Patients with a plasma MTX concentration >6 µM at 36 hours were more likely to manifest AKI. In addition, the results suggest that overweight patients have a high AKI risk and that BSA-based adjustment of MTX dose is not appropriate.

Systematic Reviews in Hematopoietic Cell Transplantation and Cellular Therapy: Considerations and Guidance from the American Society for Transplantation and Cellular Therapy, European Society for Blood and Marrow Transplantation, and Center for International Blood and Marrow Transplant Research Late Effects and Quality of Life Working Committee

Systematic reviews apply rigorous methodologies to address a prespecified, clearly formulated clinical research question. The conclusion that results is often cited to more robustly inform decision making by clinicians, third-party payers, and managed care organizations about the clinical question of interest. Although systematic reviews provide a rigorous standard, they may be infeasible when the task is to create general disease-focused guidelines comprising multiple clinical practice questions versus a single major clinical practice question. Collaborating transplantation and cellular therapy society committees also recognize that the quantity and or quality of reference sources may be insufficient for a meaningful systematic review. As the conduct of systematic reviews has evolved over time in terms of grading systems, reporting requirements, and use of technology, here we provide current guidance on methodologies, resources for reviewers, and approaches to overcome challenges in conducting systematic reviews in transplantation and cellular therapy.

Systematic reviews in hematopoietic cell transplantation and cellular therapy: considerations and guidance from the American Society for Transplantation and Cellular Therapy, European Society for Blood and Marrow Transplantation, and the Center for International Blood and Marrow Transplant Research late effects and quality of life working committee

Systematic reviews apply rigorous methodologies to address a pre-specified, clearly formulated clinical research question. The conclusion that results is often cited to more robustly inform decision-making by clinicians, third-party payers and managed care organizations about the clinical question of interest. While systematic reviews provide a rigorous standard, they may be unfeasible when the task is to create general disease-focused guidelines comprised of multiple clinical practice questions versus a single major clinical practice question. Collaborating transplantation and cellular therapy societal committees also recognize that the quantity and or quality of reference sources may be insufficient for a meaningful systematic review. As the conduct of systematic reviews has evolved over time in terms of grading systems, reporting requirements and use of technology, here we provide current guidance in methodologies, resources for reviewers, and approaches to overcome challenges in conducting systematic reviews in transplantation and cellular therapy.

Pediatric hematopoietic cell transplantation: Longitudinal trends in body mass index and outcomes

Pediatric recipients of HCT may have a high susceptibility for overweight and obesity, and obesity may negatively impact post-transplant mortality and survival. This is a single-center retrospective analysis of 297 pediatric patients who received HCT between 2005 and 2018. Patients were classified as UW, NW, OW, or OB based on age-adjusted BMI. A mixed-effects linear regression model controlling for patient, disease, and transplant-related characteristics was used to trend weight longitudinally. Comparisons were made between weight category and post-transplant outcomes. In the pretransplant period, 5.4%, 54.5%, 22.2%, and 17.8% of patients were UW, NW, OW, and OB, respectively. Five years post-transplantation, those numbers were 10.6%, 48.2%, 16.5%, and 24.7%. Overall, BMI increased 0.00094 ± 0.0001 kg/m² each day post-transplant (P < .001), with older individuals demonstrating greater rates of increase. Further, there was a larger BMI increase in patients without TBI compared with those who received TBI (1.29 ± 0.49, P = .008). Rates of acute GVHD, chronic GVHD, and viral infections, in addition to time to platelet and neutrophil engraftment and 5-year survival estimates, were not significantly different based on pretransplant BMI. Overweight and obese individuals had poorer 5-year survival based on 100-day post-transplant BMI (P = .02). Overall, pediatric HCT recipients are at risk of developing obesity, which is associated with decreased survival. Adolescents and young adults demonstrate the highest risk of weight gain, representing a vulnerable population that requires close monitoring, additional interventions, and further research.

Brazilian Nutritional Consensus in Hematopoietic Stem Cell Transplantation: Adults

The nutritional status of patients submitted to hematopoietic stem cell transplant is considered an independent risk factor, which may influence on quality of life and tolerance to the proposed treatment. The impairment of nutritional status during hematopoietic stem cell transplant occurs mainly due to the adverse effects resulting from conditioning to which the patient is subjected. Therefore, adequate nutritional evaluation and follow-up during hematopoietic stem cell transplant are essential. To emphasize the importance of nutritional status and body composition during treatment, as well as the main characteristics related to the nutritional assessment of the patient, the Brazilian Consensus on Nutrition in Hematopoietic Stem Cell Transplant: Adults was prepared, aiming to standardize and update Nutritional Therapy in this area. Dietitians, nutrition physicians and hematologists from 15 Brazilian centers thar are references in hematopoietic stem cell transplant took part.

Obesity is associated with an impaired survival in lymphoma patients undergoing autologous stem cell transplantation

Autologous hematopoietic stem cell transplantation (auto-HSCT) provides a potentially curative treatment option for relapsed and refractory lymphomas. Obesity displays an emerging epidemic risk factor for global mortality and is associated with an increased mortality in cancer patients. To date, the impact of obesity on the outcome of lymphoma patients undergoing auto-HSCT is understudied. We conducted a retrospective single-center study assessing 119 lymphoma patients who underwent auto-HSCT. Overall survival (OS) served as the primary endpoint whereas progression free survival (PFS), cumulative incidence of non-relapse related mortality (NRM) and cumulative incidence of relapse were analyzed as secondary endpoints. Obese patients (Body mass index, BMI≥30) had significantly lower OS (45.3% vs. 77.9%; p = 0.005) and PFS (29.8% vs. 67.2%; p<0.001) compared to non-obese patients at 48 months post-transplantation. The cumulative incidence of NRM displayed no significant differences while the cumulative incidence of relapse was significantly increased in patients with BMI≥30 (66.2% vs. 21.5%; p<0.001). Patients with a BMI<25 and overweight patients (BMI 25–30; 76.1% vs. 80.9%; p = 0.585), showed no significant difference in OS, whereas patients with BMI≥30 exhibited significant lower OS when compared to either of both groups (76.1% vs. 45.3%; p = .0.021 and 80.9% vs. 45.3%; p = 0.010). Furthermore, in a multivariate analysis, obesity was identified as an independent risk factor for death (Hazard ratio 2.231; 95% CI 1.024 to 4.860; p = 0.043). Further studies are needed to evaluate the reasons for the higher relapse rate causing higher mortality in obese patients.

Pretransplant hemoglobin and creatinine clearance correlate with treatment-free survival after autologous stem cell transplantation for multiple myeloma

Melphalan is given at a dose of 200 mg/m² (Mel200) prior to ASCT for multiple myeloma (MM). Pharmacokinetic (PK) studies show a high degree of interpatient variability. We aimed to test the impact of clinical factors previously shown to affect melphalan PK such as hemoglobin (Hgb), fat-free mass (FFM), and creatinine clearance (CrCl) on outcomes. Median Hgb (from day -2 to -1) and FFM were grouped as low or high relative to their sample medians, and CrCl was divided into ≥60 or <60 ml/min. In 133 MM patients, median TFS (defined as time from ASCT to initiation of next subsequent line of therapy or death) was longer in patients with lower Hgb (35 vs. 16 months, p = 0.02). Patients with both lower Hgb and CrCl experienced longer TFS compared to those with higher Hgb and CrCl (35 vs. 13 months, p = 0.03). In multivariate analysis, lower hemoglobin, lower CrCl, and a combined low hemoglobin and CrCl were strongly associated with improved TFS. Patients with a lower hemoglobin or creatinine clearance experienced significantly more toxicity. We show for the first time that Hgb and CrCl are important predictors of outcomes after Mel200. PK-directed melphalan dosing may be beneficial in achieving optimal outcomes.

Use of busulfan in conditioning for allogeneic hematopoietic stem cell transplantation in adults: a survey by the Transplant Complications Working Party of the EBMT

A survey was carried out among EBMT centers about the use of busulfan for conditioning in allogeneic stem cell transplantation. Of 109 responding centers, 106 used busulfan for conditioning, 102 in conventional myeloablative doses, and 93 in reduced doses (RIC). The route of administration was mostly intravenous, but ~10% of the centers gave the drug orally. The number of doses in i.v. administration varied and was in myeloablative conditioning mostly one (50 centers) or four (43 centers) doses a day. Seventeen of the 106 centers used pharmacokinetics for dose adjustment in myeloablative conditioning, nine in RIC. The details of pharmacokinetic monitoring varied markedly. Three quarters of the centers reported adjusting the dose based on obesity in myeloablative conditioning and about 60% in RIC. The most common method for dose calculation was ideal body weight + 0.25 × (actual body weight - ideal body weight). In conclusion, the present survey showed marked heterogeneity in the current practices of busulfan administration for conditioning. The impact of the heterogeneity is not well known. Due to this and the scarcity of support from controlled clinical studies, no clear guidelines can be presented, but some prevailing policies to be recommended were identified.

Hematopoietic Stem Cell Transplantation From Haploidentical Donors in Aplasia After Cladribine/Cytarabine Chemotherapy for Refractory Acute Myeloid Leukemia or Myelodysplastic Syndrome

INTRODUCTION

Survival rate of patients with chemorefractory acute myeloid leukemia (AML) or myelodysplastic syndrome with excess blasts (MDS-EB) is poor. Allogeneic hematopoietic cell transplantation (HCT) is the only potentially curative therapy in these patients.

PATIENTS AND METHODS

We report a retrospective analysis of outcomes of therapy of 24 patients with AML or MDS-EB refractory to high-dose salvage chemotherapy or who had failed previous HCT, who received T-cell-replete HLA haploidentical HCT in aplasia after cladribine/cytarabine-based chemotherapy followed by reduced intensity or myeloablative conditioning. All patients had active disease before commencement of the treatment.

RESULTS

Of the patients, 91.7% achieved complete remission (CR), whereas 2 patients (8.2%) died in aplasia. One-year relapse rate was 49.3%. Cumulative incidence of nonrelapse mortality (NRM) was 25.6%. In a subgroup of patients with HCT-comorbidity index score ≤ 3, NRM was 15.4%. Two-year overall survival and relapse-free survival were 30.6% and 22.6%, respectively. Incidence of grade 3 and 4 acute graft versus host disease was 21.3% and 8.3, respectively.

CONCLUSION

We found that sequential therapy with HCT in aplasia after cladribine/cytarabine chemotherapy is feasible, results in high CR rates, and has acceptable toxicity profile; however, posttransplant relapse is common in patients treated with active disease.

Effect of Conditioning Regimen Dose Reduction in Obese Patients Undergoing Autologous Hematopoietic Cell Transplantation

Data are limited on whether to adjust high-dose chemotherapy before autologous hematopoietic cell transplant (autoHCT) in obese patients. This study explores the effects of dose adjustment on the outcomes of obese patients, defined as body mass index (BMI) ≥ 30 kg/m². Dose adjustment was defined as a reduction in standard dosing ≥20%, based on ideal, reported dosing and actual weights. We included 2 groups of US patients who had received autoHCT between 2008 and 2014. Specifically, we included patients with multiple myeloma (MM, n = 1696) treated with high-dose melphalan and patients with Hodgkin or non-Hodgkin lymphomas (n = 781) who received carmustine, etoposide, cytarabine, and melphalan conditioning. Chemotherapy dose was adjusted in 1324 patients (78%) with MM and 608 patients (78%) with lymphoma. Age, sex, BMI, race, performance score, comorbidity index, and disease features (stage at diagnosis, disease status, and time to transplant) were similar between dose groups. In multivariate analyses for MM, adjusting for melphalan dose and for center effect had no impact on overall survival (P = .894) and treatment-related mortality (TRM) (P = .62), progression (P = .12), and progression-free survival (PFS; P = .178). In multivariate analyses for lymphoma, adjusting chemotherapy doses did not affect survival (P = .176), TRM (P = .802), relapse (P = .633), or PFS (P = .812). No center effect was observed in lymphoma. This study demonstrates that adjusting chemotherapy dose before autoHCT in obese patients with MM and lymphoma does not influence mortality. These results do not support adjusting chemotherapy dose in this population.

Pharmacokinetic and clinical outcomes when ideal body weight is used to dose busulfan in obese hematopoietic stem cell transplant recipients

Weight-based dosing of intravenous busulfan is widely used in hematopoietic cell transplantation. However, a variety of dosing weights have been described. The objective of this retrospective study was to determine the pharmacokinetic impact of using ideal body weight as the initial dosing weight in obese as compared to non-obese transplant recipients. The secondary objectives were to describe the use of alternative dosing weights, the impact on survival, and the rates of toxicities. The mean steady-state concentration was 779.3 ng/mL (n = 82) in the non-obese cohort and 673.7 ng/mL (n = 63) in the obese cohort (p < 0.001). A smaller proportion of concentrations were below goal in the non-obese cohort (10% vs. 41%, p < 0.001). Ideal body weight and adjusted body weights with a 25 and 40% correction factor are appropriate in non-obese patients; adjusted body weights with a 25 and 40% correction factor are appropriate in obese patients. There was no difference in overall survival (p = 0.18); there was a difference in median progression-free survival (1078 vs. 500 days, p = 0.045) in the non-obese compared to obese cohorts. The use of ideal body weight to dose busulfan resulted in lower steady-state concentrations, a larger proportion of subtherapeutic concentrations, and worse progression-free survival in obese patients.

Impact of Dose-Adjusted Melphalan in Obese Patients Undergoing Autologous Stem Cell Transplantation

Limited guidance exists for dosing melphalan for autologous stem cell transplantation (ASCT) in the obese patient population, because the current literature reports conflicting clinical outcomes between obese and nonobese patients. In 2014, the American Society for Blood and Marrow Transplantation published conditioning chemotherapy dosing guidelines for obese patients and recommended dosing of melphalan using actual body weight (ABW) in the body surface area calculation. The practice at Barnes-Jewish Hospital has consistently been to dose melphalan using adjusted body weight (AdBW), with a 20% correction when a patient weighs ≥120% of his or her ideal body weight (IBW). The purpose of this study was to compare outcomes of melphalan ASCT in patients with multiple myeloma between obese (≥120% IBW) and nonobese (<120% IBW) populations. This retrospective, single-center study included adult patients with multiple myeloma undergoing first ASCT with melphalan conditioning between January 2009 and December 2012. Patient demographic data, transplantation characteristics, and clinical outcomes were collected. The primary outcome was 3-year event-free survival (EFS). Secondary outcomes included response at 100 days post-transplantation, 3-year overall survival, treatment-related mortality (TRM), time to neutrophil engraftment, and hospital length of stay (LOS). To ensure that melphalan dosage adjustment in the obese population did not impact efficacy, the primary outcome was assessed using a noninferiority design, with a predetermined noninferiority margin of 7%. Assuming a 70% 3-year EFS in the nonobese population, a noninferiority margin of 7%, a power of 80%, and an α value of .05, an analysis of 280 patients was required. A total of 270 patients, including 171 (63%) obese patients and 99 (37%) nonobese patients, met our inclusion criteria. Baseline characteristics were well matched between the 2 cohorts, including high-risk cytogenetics, disease severity at diagnosis, and use of maintenance therapy, with the only detectable differences related to weight itself. The 3-year EFS was 41% for the total cohort, with fewer events occurring in the obese cohort compared with the nonobese cohort (51% versus 40%; P = .0025). The 95% lower confidence limit established noninferiority. High-risk cytogenetics, disease severity at diagnosis, and therapy response pre- and post-ASCT were all associated with significantly shorter EFS. No between-group differences in TRM, time to engraftment, or hospital LOS were noted. This retrospective, single-center study found that using AdBW to dose melphalan in obese patients was not inferior to the nonobese population in terms of 3-year EFS. This study adds to the limited evidence on melphalan dosing and suggests that transplantation efficacy is not affected by AdBW dosing in obese patients. Further studies are needed to provide additional insight into the pharmacokinetic differences and best dosing practices for obese patients.

[Dose adaptation of the drugs used for hematopoietic stem-cell transplantation in patients with comorbidity: Obesity, chronic renal disease or hepatopathy: Guidelines from the Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC)]

In September 2016 in Lille, France, the Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC) organized the 7th Allogeneic Stem Cell Transplantation Clinical Practices Harmonization Workshop Series. Our work group focused on chemotherapy drug dose adaptation for hematopoietic stem cell transplantation patients presenting a comorbidity. The purpose of this workshop was to provide recommendations on chemotherapy drug dose adaptation for patient populations receiving hematopoietic stem cell transplantation who also had the following comorbidities: obesity, chronic kidney disease and hepatopathy.

Creation and evaluation of a cancer chemotherapy order review guide for use at a community hospital

The proper evaluation of cancer chemotherapy orders is necessary for patients to receive safe and effective treatment. The chemotherapy treatment setting is evolving resulting in hospital pharmacists without extensive oncology training or experience now being responsible for evaluation of chemotherapy orders. The primary objective was to create a step-by-step chemotherapy order evaluation guide with a detailed explanation for each step. The secondary objective was to evaluate non-oncology trained pharmacists' ability to accurately review simulated chemotherapy orders post-education using the guide. A two-page chemotherapy order evaluation guide was created based on an accepted method of chemotherapy order review consisting of the following eight steps: regimen verification, clinical trial protocol verification, body surface area calculation, dose calculation, laboratory values, emesis prophylaxis, adjunctive or supportive care measures, and pharmacy labels. A literature search was performed for each step. A detailed explanation for each step was written as a separate component from the guide to encompass the literature search information and current guidelines in a more comprehensive manner. Non-oncology trained community hospital pharmacists were educated on use of the guide for approximately 30 min. The guide was evaluated using timed simulated chemotherapy orders pre- and post-education consisting of a general chemotherapy order and a carboplatin dosing order. Nineteen pharmacists were tested with simulated chemotherapy orders. A significant difference was detected between the pre- and post-education for both the general chemotherapy (p = 0.00032) order and carboplatin dosing order (p = 0.031).

Pharmacokinetics, Pharmacodynamics, and Pharmacogenomics of Immunosuppressants in Allogeneic Hematopoietic Cell Transplantation: Part II

Part I of this article included a pertinent review of allogeneic hematopoietic cell transplantation (alloHCT), the role of postgraft immunosuppression in alloHCT, and the pharmacokinetics, pharmacodynamics, and pharmacogenomics of the calcineurin inhibitors and methotrexate. In this article (Part II), we review the pharmacokinetics, pharmacodynamics, and pharmacogenomics of mycophenolic acid (MPA), sirolimus, and the antithymocyte globulins (ATG). We then discuss target concentration intervention (TCI) of these postgraft immunosuppressants in alloHCT patients, with a focus on current evidence for TCI and on how TCI may improve clinical management in these patients. Currently, TCI using trough concentrations is conducted for sirolimus in alloHCT patients. Several studies demonstrate that MPA plasma exposure is associated with clinical outcomes, with an increasing number of alloHCT patients needing TCI of MPA. Compared with MPA, there are fewer pharmacokinetic/dynamic studies of rabbit ATG and horse ATG in alloHCT patients. Future pharmacokinetic/dynamic research of postgraft immunosuppressants should include '-omics'-based tools: pharmacogenomics may be used to gain an improved understanding of the covariates influencing pharmacokinetics as well as proteomics and metabolomics as novel methods to elucidate pharmacodynamic responses.

Pharmacokinetics, Pharmacodynamics and Pharmacogenomics of Immunosuppressants in Allogeneic Haematopoietic Cell Transplantation: Part I

Although immunosuppressive treatments and target concentration intervention (TCI) have significantly contributed to the success of allogeneic haematopoietic cell transplantation (alloHCT), there is currently no consensus on the best immunosuppressive strategies. Compared with solid organ transplantation, alloHCT is unique because of the potential for bidirectional reactions (i.e. host-versus-graft and graft-versus-host). Postgraft immunosuppression typically includes a calcineurin inhibitor (cyclosporine or tacrolimus) and a short course of methotrexate after high-dose myeloablative conditioning, or a calcineurin inhibitor and mycophenolate mofetil after reduced-intensity conditioning. There are evolving roles for the antithymyocyte globulins (ATGs) and sirolimus as postgraft immunosuppression. A review of the pharmacokinetics and TCI of the main postgraft immunosuppressants is presented in this two-part review. All immunosuppressants are characterized by large intra- and interindividual pharmacokinetic variability and by narrow therapeutic indices. It is essential to understand immunosuppressants' pharmacokinetic properties and how to use them for individualized treatment incorporating TCI to improve outcomes. TCI, which is mandatory for the calcineurin inhibitors and sirolimus, has become an integral part of postgraft immunosuppression. TCI is usually based on trough concentration monitoring, but other approaches include measurement of the area under the concentration-time curve (AUC) over the dosing interval or limited sampling schedules with maximum a posteriori Bayesian personalization approaches. Interpretation of pharmacodynamic results is hindered by the prevalence of studies enrolling only a small number of patients, variability in the allogeneic graft source and variability in postgraft immunosuppression. Given the curative potential of alloHCT, the pharmacodynamics of these immunosuppressants deserves to be explored in depth. Development of sophisticated systems pharmacology models and improved TCI tools are needed to accurately evaluate patients' exposure to drugs in general and to immunosuppressants in particular. Sequential studies, first without and then with TCI, should be conducted to validate the clinical benefit of TCI in homogenous populations; randomized trials are not feasible, because there are higher-priority research questions in alloHCT. In Part I of this article, we review the alloHCT process to facilitate optimal design of pharmacokinetic and pharmacodynamics studies. We also review the pharmacokinetics and TCI of calcineurin inhibitors and methotrexate.

Personalized fludarabine dosing to reduce nonrelapse mortality in hematopoietic stem-cell transplant recipients receiving reduced intensity conditioning

Patients undergoing hematopoietic cell transplantation (HCT) with reduced intensity conditioning (RIC) commonly receive fludarabine. Higher exposure of F-ara-A, the active component of fludarabine, has been associated with a greater risk of nonrelapse mortality (NRM). We sought to develop a model for fludarabine dosing in adult HCT recipients that would allow for precise dose targeting and predict adverse clinical outcomes. We developed a pharmacokinetic model from 87 adults undergoing allogeneic RIC HCT that predicts F-ara-A population clearance (Clpop) accounting for ideal body weight and renal function. We then applied the developed model to an independent cohort of 240 patients to identify whether model predictions were associated with NRM and acute graft versus host disease (GVHD). Renal mechanisms accounted for 35.6% of total F-ara-A Clpop. In the independent cohort, the hazard ratio of NRM at day 100 was significantly higher in patients with predicted F-ara-A clearance (Clpred) <8.50 L/h (P < 0.01) and area under the curve (AUCpred) >6.00 μg × h/mL (P = 0.01). A lower Clpred was also associated with more NRM at month 6 (P = 0.01) and trended toward significance at 12 months (P = 0.05). In multivariate analysis, low fludarabine clearance trended toward higher risk of acute GVHD (P = 0.05). We developed a model that predicts an individual's systemic F-ara-A exposure accounting for kidney function and weight. This model may provide guidance in dosing especially in overweight individuals and those with altered kidney function.

Personalizing Busulfan-Based Conditioning: Considerations from the American Society for Blood and Marrow Transplantation Practice Guidelines Committee

The Practice Guidelines Committee of the American Society of Blood or Marrow Transplantation (ASBMT) sought to develop an evidence-based review about personalizing busulfan-based conditioning. The Committee sought to grade the relevant published studies (June 1, 2008 through March 31, 2016) according to criteria set forth by the Steering Committee for Evidence Based Reviews from ASBMT. Unfortunately, the published literature was too heterogeneous and lacked adequately powered and sufficiently controlled studies for this to be feasible. Despite this observation, the continued interest in this topic led the Practice Guidelines Committee to develop a list of most frequently asked questions (FAQs) regarding personalized busulfan dosing. This "Considerations" document is a list of these FAQs and their responses, addressing topics of practical relevance to hematopoietic cell transplantation clinicians.

Effect of severe hypoalbuminemia on toxicity of high-dose melphalan and autologous stem cell transplantation in patients with AL amyloidosis

High-dose melphalan with stem cell transplantation (HDM/SCT) extends survival and induces hematologic and clinical responses in patients with light chain (AL) amyloidosis. Eighty percent of melphalan is bound to plasma proteins (60% albumin-bound). We hypothesized that patients with profound hypoalbuminemia have a greater free melphalan fraction and more toxicity. Patients with AL amyloidosis treated with HDM/SCT between 2011 and 2014 with severe hypoalbuminemia (SH), defined as serum albumin ⩽2 g/dL were studied retrospectively. Sixteen patients with SH were identified. Forty-one patients without severe hypoalbuminemia (WSH) treated between 2011 and 2012 served as control. The incidence of acute renal failure requiring hemodialysis was 25% among patients with SH, compared with 5% among patients WSH (P=0.05). Not all patients who needed dialysis required it long term; 6.25% for SH and 2.44% for WSH (P=0.49). The rates of grade 3 or 4 febrile neutropenia and gastrointestinal toxicities were not significantly different between the groups. Engraftment kinetics were similar for both groups. Grade 4 renal toxicity and grade 3 lightheadedness were more frequent in patients with SH undergoing HDM/SCT for AL amyloidosis. Further studies into the mechanism of increased renal toxicity in patients with SH are warranted.

Antithymocyte globulin in allogeneic hematopoietic cell transplantation: benefits and limitations

Significant advances have been made in allogeneic hematopoietic cell transplantation by reducing toxicities and optimizing its efficacy. Antithymocyte globulin (ATG) is an important in vivo T-cell depletion strategy, which reduces the risk of graft-versus-host disease in HLA-matched or -mismatched donor allografting. ATG effectively targets alloreactive T cells at the expense of potentially increasing the risk of post-hematopoietic cell transplantation infections and delayed immune reconstitution. We summarize the targets, mechanisms, various preparations of ATG, the growing role of ATG in prevention of graft-versus-host disease in various transplant modalities as well as emerging data on pharmacokinetic modeling for individualized ATG dosing. Further research is needed to optimize the ATG administration while minimizing the toxicities.

Success of an International Learning Health Care System in Hematopoietic Cell Transplantation: The American Society of Blood and Marrow Transplantation Clinical Case Forum

The American Society for Blood and Marrow Transplantation (ASBMT) Clinical Case Forum (CCF) was launched in 2014 as an online secure tool to enhance interaction and communication among hematopoietic cell transplantation (HCT) professionals worldwide through the discussion of challenging clinical care issues. After 14 months, we reviewed clinical and demographical data of cases posted in the CCF from January 29, 2014 to March 18, 2015. A total of 137 cases were posted during the study period. Ninety-two cases (67%) were allogeneic HCT, 29 (21%) were autologous HCT, and in 16 (12%), the type of transplantation (autologous versus allogeneic) was still under consideration. The diseases most frequently discussed included non-Hodgkin lymphoma (NHL; n = 30, 22%), acute myeloid leukemia (n = 23, 17%), and multiple myeloma (MM; n = 20, 15%). When compared with the US transplantation activity reported by the US Department of Health and Human Services, NHL and acute lymphoblastic leukemia cases were over-represented in the CCF, whereas MM was under-represented (P < .001). A total of 259 topics were addressed in the CCF with a median of 2 topics/case (range, 1 to 6). Particularly common topics included whether transplantation was indicated (n = 57, 41%), conditioning regimen choice (n = 44, 32%), and post-HCT complications after day 100 (n = 43, 31%). The ASBMT CCF is a successful tool for collaborative discussion of complex cases in the HCT community worldwide and may allow identification of areas of controversy or unmet need from clinical, educational and research perspectives.

Adjusting Cyclophosphamide Dose in Obese Patients with Lymphoma Is Safe and Yields Favorable Outcomes after Autologous Hematopoietic Cell Transplantation

No clear dosing guidelines exist for cyclophosphamide (Cy) dose adjustments in obese patients treated with high-dose chemoradiotherapy followed by autologous hematopoietic cell transplantation (HCT). We prospectively compared the outcomes of high-dose Cy/total body irradiation (TBI) conditioning in 147 non-Hodgkin lymphoma (NHL) patients in 3 weight groups: nonobese (<120% ideal body weight [IBW]; n = 72), overweight (120% to 149% IBW; n = 46), and obese (≥150% IBW; n = 29). Nonobese and overweight patients received Cy (120 mg/kg of total body weight, intravenously) and TBI (1320 cGy), whereas obese patients (median body mass index, 36) received an adjusted Cy dose based on IBW plus 50% of the difference between total body weight and IBW (AdjBW50). The median patient age was 57 years (range, 19 to 73). The most common diagnoses were diffuse large B cell lymphoma (n = 57) and mantle cell lymphoma (n = 51). Three-year overall survival was 61% (95% confidence interval [CI], 48% to 72%) for nonobese patients, 68% (95% CI, 52% to 82%) for overweight patients, and 80% (95% CI, 62% to 93%) for obese patients. Cumulative incidence of relapse (48%, 43%, and 38%, respectively) and nonrelapse mortality (∼4%) were similar in all groups. Hemorrhagic cystitis and cardiac toxicity were rare events. Our data show that the AdjBW50 formula can be safely and effectively used for Cy dose adjustments in obese patients treated for NHL with high-dose Cy/TBI conditioning followed by autologous HCT.

Role of cytotoxic therapy with hematopoietic cell transplantation in the treatment of Hodgkin lymphoma: guidelines from the American Society for Blood and Marrow Transplantation

The role of hematopoietic cell transplantation (HCT) in the therapy of Hodgkin lymphoma (HL) in pediatric and adult patients is reviewed and critically evaluated in this systematic evidence-based review. Specific criteria were used for searching the published literature and for grading the quality and strength of the evidence and the strength of the treatment recommendations. Treatment recommendations based on the evidence are included and were reached unanimously by a panel of HL experts. Both autologous and allogeneic HCT offer a survival benefit in selected patients with advanced or relapsed HL and are currently part of standard clinical care. Relapse remains a significant cause of failure after both transplant approaches, and strategies to decrease the risk of relapse remain an important area of investigation.