Association of busulfan exposure with survival and toxicity after haemopoietic cell transplantation in children and young adults: a multicentre, retrospective cohort analysis.

Authors: Imke H Bartelink, Arief Lalmohamed, Elisabeth M L van Reij...

BACKGROUND

Intravenous busulfan combined with therapeutic drug monitoring to guide dosing improves outcomes after allogeneic haemopoietic cell transplantation (HCT). The best method to estimate busulfan exposure and optimum exposure in children or young adults remains unclear. We therefore assessed three approaches to estimate intravenous busulfan exposure (expressed as cumulative area under the curve [AUC]) and associated busulfan AUC with clinical outcomes in children or young adults undergoing allogeneic HCT.

METHODS

In this retrospective analysis, patients from 15 centres in the Netherlands, USA, Canada, Switzerland, UK, Italy, Germany, and Australia who received a busulfan-based conditioning regimen between March 18, 2001, and Feb 12, 2015, were included. Cumulative AUC was calculated by numerical integration using non-linear mixed effect modelling (AUC), non-compartmental analysis (AUC from 0 to infinity [AUC] and to the next dose [AUC]), and by individual centres using various approaches (AUC). The main outcome of interest was event-free survival. Other outcomes of interest were graft failure or relapse, or both; transplantation-related mortality; acute toxicity (veno-occlusive disease or acute graft versus-host disease [GvHD]); chronic GvHD; overall survival; and chronic-GvHD-free event-free survival. We used propensity-score-adjusted Cox proportional hazard models, Weibull models, and Fine-Gray competing risk regressions for statistical analyses.

FINDINGS

790 patients were enrolled, 674 of whom were included: 274 (41%) with malignant and 400 (59%) with non-malignant disease. Median age was 4·5 years (IQR 1·4-10·7). The median busulfan AUC was 74·4 mg × h/L (95% CI 31·1-104·6), which correlated with the standardised method AUC (r=0·74), but the latter correlated poorly with AUC (r=0·35). Estimated 2-year event-free survival was 69·7% (95% CI 66·2-73·0). Event-free survival at 2 years was 77·0% (95% CI 72·1-82·9) in the 257 patients with an optimum intravenous busulfan AUC of 78-101 mg × h/L compared with 66·1% (60·9-71·4) in the 235 patients at the low historical target of 58-86 mg × h/L and 49·5% (29·2-66·0) in the 44 patients with a high (>101 mg × h/L) busulfan AUC (p=0·011). Compared with the low AUC group, graft failure or relapse occurred less frequently in the optimum AUC group (hazard ratio [HR] 0·57, 95% CI 0·39-0·84; p=0·0041). Acute toxicity (HR 1·69, 1·12-2·57; p=0·013) and transplantation-related mortality (2·99, 1·82-4·92; p<0·0001) were significantly higher in the high AUC group (>101 mg × h/L) than in the low AUC group (<78 mg × h/L), independent of indication; no difference was noted between AUC groups for chronic GvHD (<78 mg × h/L vs ≥78 mg × h/L, HR 1·30, 95% CI 0·73-2·33; p=0·37).

INTERPRETATION

Improved clinical outcomes are likely to be achieved by targeting the busulfan AUC to 78-101 mg × h/L using a new validated pharmacokinetic model for all indications.

FUNDING

Research Allocation Program and the UCSF Helen Friller Family Comprehensive Cancer Center and the Mt Zion Health Fund of the University of California, San Francisco.

Topics: Adolescent; Adult; Area Under Curve; Busulfan; Child; Child, Preschool; Cohort Studies; Disease-Free Survival; Dose-Response Relationship, Drug; Female; Graft Rejection; Graft Survival; Graft vs Host Disease; Hematopoietic Stem Cell Transplantation; Humans; Infant; Male; Recurrence; Retrospective Studies; Transplantation Conditioning; Transplantation, Homologous; Treatment Outcome

PubMed: 27746112
DOI: 10.1016/S2352-3026(16)30114-4

Randomized Controlled Trial

Treosulfan compared with reduced-intensity busulfan improves allogeneic hematopoietic cell transplantation outcomes of older acute myeloid leukemia and myelodysplastic syndrome patients: Final analysis of a prospective randomized trial.

Authors: Dietrich W Beelen, Matthias Stelljes, Péter Reményi...

The phase III study was designed to compare event-free survival (EFS) after treosulfan-based conditioning with a widely applied reduced-intensity conditioning (RIC) busulfan regimen in older or comorbid patients with acute myeloid leukemia (AML) or myelodysplastic syndrome (MDS) undergoing allogeneic hematopoietic cell transplantation (HCT). A previously reported confirmatory interim analysis of the randomized clinical study including 476 patients demonstrated statistically significant noninferiority for treosulfan with clinically meaningful improvement in EFS. Here, the final study results and pre-specified subgroup analyses of all 570 randomized patients with completed longer-term follow-up are presented. Patients presenting HCT-specific comorbidity index >2 or aged ≥50 years were randomly assigned (1:1) to intravenous (IV) fludarabine with either treosulfan (30 g/m IV) or busulfan (6.4 mg/kg IV) after stratification by disease risk group, donor type, and participating institution. The primary endpoint was EFS with disease recurrence, graft failure, or death from any cause as events. EFS of patients (median age 60 years) was superior after treosulfan compared to RIC busulfan: 36-months-EFS rate 59.5% (95% CI, 52.2-66.1) vs. 49.7% (95% CI, 43.3-55.7) with a hazard ratio (HR) of 0.64 (95% CI, 0.49-0.84), p = 0.0006. Likewise, overall survival (OS) with treosulfan was superior compared to busulfan: 36-month-OS rate 66.8% vs. 56.3%; HR 0.64 (95% CI, 0.48-0.87), p = 0.0037. Post hoc analyses revealed that these differences were consistent with the confirmatory interim analysis, and thereby the treosulfan regimen appears particularly suitable for older AML and MDS patients.

Topics: Aged; Busulfan; Graft vs Host Disease; Hematopoietic Stem Cell Transplantation; Humans; Leukemia, Myeloid, Acute; Middle Aged; Myelodysplastic Syndromes; Prospective Studies; Transplantation Conditioning; Vidarabine

PubMed: 35617104
DOI: 10.1002/ajh.26620

Meta-Analysis

Authors: Ruiyang Pu, Jing Liu, Aiping Zhang...

OBJECTIVE

Modeling methods for busulfan-induced oligoasthenozoospermia are controversial. We aimed to systematically review the modeling method of busulfan-induced oligospermia and asthenozoospermia, and analyze changes in various evaluation indicators at different busulfan doses over time.

METHODS

We searched the Cochrane Library, PubMed databases, Web of Science, the Chinese National Knowledge Infrastructure, and the Chinese Biomedical Literature Service System until April 9, 2022. Animal experiments of busulfan-induced spermatogenesis dysfunction were included and screened. The model mortality and parameters of the evaluation indicators were subjected to meta-analysis.

RESULTS

Twenty-nine animal studies were included (control/model: 669/1829). The mortality of mice increased with busulfan dose. Significant spermatogenesis impairment occurred within 5 weeks, regardless of busulfan dose (10-40 mg/kg). Testicular weight (weighted mean difference [WMD]: - 0.04, 95% CI: - 0.05, - 0.03), testicular index (WMD: - 2.10, 95% CI: - 2.43, - 1.76), and Johnsen score (WMD: - 4.67, 95% CI: - 5.99, - 3.35) were significantly decreased. The pooled sperm counts of the model group were reduced by 32.8 × 10/ml (WMD: - 32.8, 95% CI: - 44.34, - 21.28), and sperm motility decreased by 37% (WMD: - 0.37, 95% CI: - 0.47, - 0.27). Sperm counts decreased slightly (WMD: - 3.03, 95% CI: - 3.42, - 2.64) in an intratesticular injection of low-dose busulfan (4 - 6 mg/kg), and the model almost returned to normal after one seminiferous cycle.

CONCLUSION

The model using low-dose busulfan (10 - 20 mg/kg) returned to normal after 10 - 15 weeks. However, in some spermatogenesis cycles, testicular weight reduction and testicular spermatogenic function damage were not proportional to busulfan dose. Sperm counts and motility results in different studies had significant heterogeneity. Standard protocols for sperm assessment in animal models were needed to reduce heterogeneity between studies.

Topics: Humans; Mice; Male; Animals; Oligospermia; Busulfan; Asthenozoospermia; Sperm Count; Sperm Motility; Semen

PubMed: 36508035
DOI: 10.1007/s10815-022-02674-y

Authors: Tim Bognàr, Moises Garcia-Rosa, Arief Lalmohamed...

Allogeneic hematopoietic cell transplantation (HCT) is a potentially curative treatment strategy for patients with inborn errors of immunities (IEIs). The objective of this study was to assess the optimal busulfan exposure before allogeneic HCT for patients with an IEI who received an IV busulfan-based conditioning regimen. Patients from 17 international centers were included. The main outcome of interest was event-free survival (EFS). Patients were categorized into 4 IEI subgroups: combined immunodeficiency (CID), severe combined immunodeficiency (SCID), neutrophil disorders, and hemophagocytic lymphohistiocytosis (HLH)-related disorders. Busulfan exposure was calculated by individual centers (area under the curve [AUC]CENTER) and re-estimated using a nonlinear mixed-effects model (NONMEM; exposure defined as AUCNONMEM). Overall, 562 patients were included: 173 (30.8%) with CID, 154 (27.4%) with SCID, 101 (18.0%) with HLH-related disorders, and 134 (23.8%) with neutrophil disorders. The median busulfan AUCNONMEM was 69.0 mg × h/L and correlated poorly with the AUCCENTER (r2 = 0.54). In patients with SCID, HLH-related, and neutrophil disorders with a busulfan AUCNONMEM of 70 to 90 mg × h/L, 2-year EFS was superior to <70 mg × h/L, and >90 mg ×h/L. Full donor chimerism increased with higher busulfan AUCNONMEM, plateauing at 90 mg × h/L. For patients with CID, the optimal AUCNONMEM for donor chimerism was found to be >70 mg × h/L. Improved EFS and higher donor chimerism may be achieved by targeting a cumulative busulfan AUCNONMEM of 80 mg × h/L (range, 70-90). Our study stresses the importance of uniformly using a validated population pharmacokinetic model to estimate AUCNONMEM.

Topics: Humans; Busulfan; Hematopoietic Stem Cell Transplantation; Transplantation Conditioning; Male; Infant; Female; Child, Preschool; Child; Treatment Outcome; Adolescent; Graft vs Host Disease; Transplantation, Homologous

PubMed: 39074263
DOI: 10.1182/bloodadvances.2024013275

Authors: M Hassan, P Ljungman, P Bolme...

Busulfan is widely used as a component of the myeloablative therapy in bone marrow transplantation. Recent studies have shown that the drug disposition is altered in children and is associated with less therapeutic effectiveness, lower toxicities, and higher rates of engraftment failure. We have evaluated the bioavailability of the drug in two groups of patients: eight children between 1.5 and 6 years of age and eight older children and adults between 13 and 60 years. Oral bioavailability showed a large interindividual variation. In children, the bioavailability ranged from 0.22 to 1.20, and for adults, it was within the range 0.47 to 1.03. The elimination half-life after intravenous administration in children (2.46 +/- 0.27 hours; mean +/- SD) did not differ from that obtained for adults (2.61 +/- 0.62 hours). However, busulfan clearance normalized to body weight was significantly higher in children (3.62 +/- 0.78 mL.min-1.kg-1) than that in adults (2.49 +/- 0.52 mL.min-1.kg-1). Also, the distribution volume normalized for body weight was significantly higher in children (0.74 +/- 0.10 L.kg-1) compared with 0.56 +/- 0.10 L. kg-1 in adults. The difference in clearance between children and adults was not statistically significant when normalized to body surface area, which most probably shows that busulfan dosage should be calculated on the basis of surface area rather than body weight. However, to avoid drug-related toxicities, drug monitoring and an individual dose adjustment should be considered because of the variability in busulfan bioavailability.

Topics: Administration, Oral; Adult; Age Factors; Biological Availability; Busulfan; Child, Preschool; Female; Humans; Infant; Injections, Intravenous; Male; Metabolic Clearance Rate; Middle Aged

PubMed: 7919328
DOI: No ID Found

Authors: J S Malpas

Topics: Busulfan; Female; Humans; Middle Aged; Primary Myelofibrosis

PubMed: 5655243
DOI: 10.1177/003591576806100536

Authors: Ke Hu, Qinran Zhu, Jiaqi Zou...

BACKGROUND

Busulfan is the most commonly used drug for the treatment of chronic myelogenous leukemia and pretreatment for hematopoietic stem cell transplantation, which can damage the reproductive and immune system. However, little is known about the protein expression profiling in busulfan treated testis.

METHODS

This research studies the proteomics for busulfan-induced spermatogenesis disorder. The model of busulfan-induced mouse spermatogenesis disorder was subjected to label-free quantification proteomics analysis. Clustering heatmap, gene ontology, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and protein interaction analyses were performed and validated by molecular experiments.

RESULTS

The busulfan-treated mouse model showed abnormal testis morphology and reduced sperm number and testis weight. Testicular and sperm damage was most severe at 30 days after busulfan treatment. The busulfan-treated mouse testes were subjected to label-free quantification proteomics, which revealed 190 significantly downregulated proteins including lactate dehydrogenase A like 6B (LDHAL6B) and ubiquitin-specific protease 7 (USP7). In addition, the testis and spermatozoa in the epididymis progressively improved from 70 to 80 days after busulfan treatment, and that the testis weight and spermatozoa number gradually increased from 40 to 80 days after busulfan treatment. Western blotting revealed that LDHAL6B protein significantly increased at 10 days, decreased from 20 to 60 days, and then gradually elevated from 70 to 80 days after busulfan treatment.

CONCLUSION

We revealed 190 significantly downregulated proteins in busulfan-treated mouse testes at 30 days and indicated that 70 days is the cut-off point of spermatogenic recovery for busulfan-treated mouse testis, increasing our understanding of this reproductive disorder model. An increased understanding of busulfan's toxic effect will help to prevent and treat reproductive diseases.

Topics: Busulfan; Animals; Male; Spermatogenesis; Mice; Proteomics; Testis; Spermatozoa; Disease Models, Animal; Antineoplastic Agents, Alkylating

PubMed: 39697060
DOI: 10.1080/07853890.2024.2442534

Comparative Study Randomized Controlled Trial

Authors: Gianluca Cavallaro, Anna Grassi, Chiara Pavoni...

We report the long-term results of a randomized trial (GITMO, AML-R2), comparing 1:1 the combination of busulfan and cyclophosphamide (BuCy2, n = 125) and the combination of busulfan and fludarabine (BuFlu, n = 127) as conditioning regimen in acute myeloid leukemia patients (median age 51 years, range 40-65) undergoing allogeneic hematopoietic stem cell transplantation. With a median follow-up of 6 years, significantly better non-relapse mortality (NRM) was confirmed in BuFlu recipients, which is sustained up to 4 years after transplant (10% vs. 20%, p = 0.0388). This difference was higher in patients older than 51 years (11% in BuFlu vs. 27% in BuCy2, p = 0.0262). The cumulative incidence of relapse, which was the first cause of death in the entire study population, did not differ between the two randomized arms. Similarly, the leukemia-free survival (LFS) and overall survival (OS) were not different in the two cohorts, even when stratifying patients per median age. Graft-and relapse-free survival (GRFS) in BuFlu arm vs. the BuCy2 arm was 25% vs. 20% at 4 years and 20% vs. 17% at 10 years. Hence, the benefit gained by NRM reduction is not offsets by an increased relapse. Leukemia relapse remains a major concern, urging the development of new therapeutic approaches.

Topics: Adult; Aged; Female; Humans; Male; Middle Aged; Antineoplastic Combined Chemotherapy Protocols; Busulfan; Cyclophosphamide; Follow-Up Studies; Hematopoietic Stem Cell Transplantation; Immunosuppressive Agents; Leukemia, Myeloid, Acute; Transplantation Conditioning; Transplantation, Homologous; Vidarabine

PubMed: 39168989
DOI: 10.1038/s41408-024-01116-5

Combining Three Different Pretransplantation Scores Improves Predictive Value in Patients after Haploidentical Stem Cell Transplantation with Thiotepa, Busulfan, and Fludarabine Conditioning and Post-Transplantation Cyclophosphamide.

Authors: Albert Esquirol, Maria Jesus Pascual, Irene Garcia-Cadenas...

One hundred and sixty-one patients underwent haploidentical stem cell transplantation (haploSCT) with thiotepa, busulfan, and fludarabine conditioning followed by post-transplantation cyclophosphamide (PTCy) (on days +3 and +4) and tacrolimus as graft-versus-host disease prophylaxis. Forty-two percent of patients had a high or very high revised Disease Risk Index (rDRI), 55% had an European Society for Blood and Marrow Transplantation risk score (EBMT-RS) ≥4, and 36% had an age-adjusted Hematopoietic Cell Transplant Comorbidity Index (HCT-CI-age) score ≥3. Each of these was considered an unfavorable score. Using the pretransplantation unfavorable scores that had an independent impact on each transplantation outcome studied in multivariate analysis allowed for better stratification of patient outcomes. Thus, the 3-year overall survival (OS) in patients with 0, 1, 2, and 3 unfavorable scores was 86%, 56%, 36%, and 24%, respectively. Nonrelapse mortality (NRM) was negatively impacted by the EBMT-RS and the HCT-CI-age score (3-year NRM in patients with 0, 1, and 2 unfavorable scores was 12%, 33%, and 43%, respectively), whereas the EBMT-RS and the rDRI had an impact on the 3-year relapse incidence (8%, 18%, and 41% in patients with 0, 1, and 2 unfavorable scores, respectively). In conclusion, our study shows that combining 2 or 3 of these well-defined pretransplantation scores improves the ability to predict transplantation outcomes in the setting of haploSCT with PTCy.

Topics: Busulfan; Cyclophosphamide; Graft vs Host Disease; Hematopoietic Stem Cell Transplantation; Humans; Thiotepa; Transplantation Conditioning; Vidarabine

PubMed: 33775908
DOI: 10.1016/j.jtct.2021.03.021

Authors: Hai-Tao Li, Kun Zhong, Yun-Fei Xia...

Male infertility is a global concern, with a noticeable increase in the decline of spermatogenesis and sperm quality. However, there are limited clinically effective treatments available. This study aimed to investigate the potential effectiveness of puerarin in treating male infertility, which leads to gonadal changes. The results obtained from various analyses such as CASA, immunofluorescence, DIFF-Quick, hematoxylin and eosin (H&E), and periodic acid-Schiff (PAS) staining demonstrated that puerarin supplementation significantly alleviated the busulfan-induced reduction in spermatogenesis and sperm quality in both young and adult mice. Furthermore, puerarin exhibited a marked improvement in the damage caused by busulfan to the architecture of seminiferous tubules, causal epididymis, blood-testicular barrier (BTB), as well as spermatogonia and Sertoli cells. Similarly, puerarin significantly reduced the levels of total antioxidant capacity (T-AOC), malondialdehyde (MDA), and caspase-3 in the testes of busulfan-induced mice, as determined by microplate reader analysis. Additionally, RNA-seq data, RT-qPCR, and western blotting revealed that puerarin restored the abnormal gene expressions induced by busulfan to nearly healthy levels. Notably, puerarin significantly reversed the impact of busulfan on the expression of marker genes involved in spermatogenesis and oxidative stress. Moreover, puerarin suppressed the phosphorylation of p38, ERK1/2, and JNK in the testes, as observed through testicular analysis. Consequently, this study concludes that puerarin may serve as a potential alternative for treating busulfan-induced damage to male fertility by inactivating the testicular MAPK pathways. These findings may pave the way for the use of puerarin in addressing chemotherapy- or other factors-induced male infertility in humans.

Topics: Humans; Male; Animals; Mice; Busulfan; Semen; Spermatogenesis; Testis; Infertility, Male

PubMed: 37516022
DOI: 10.1016/j.biopha.2023.115231