Etoposide pharmacokinetics impact the outcomes of lymphoma patients treated with BEAM regimen and ASCT: a multicenter study of the LYmphoma Study Association (LYSA)

BeEAM (Bendamustine, Etoposide, Cytarabine, Melphalan) Versus BEAM (Carmustine, Etoposide, Cytarabine, Melphalan) as Conditioning Regimen Before Autologous Haematopoietic Cell Transplantation: A Systematic Review and Meta-Analysis

High-dose chemotherapy followed by autologous stem cell transplantation (ASCT) is a standard of care for selected patients with refractory/relapsed Hodgkin's lymphoma (HL) or non-Hodgkin's lymphoma (NHL), and it is also used as first-line clinical consolidation option for some aggressive NHL subtypes. Conditioning regimen prior to ASCT is one of the essential factors related with clinical outcomes post transplant. The conditioning regimen of carmustine, etoposide, cytarabine, and melphalan (BEAM) traditionally is considered the standard of care for patients with lymphoma who are eligible for transplantation. Replacement of carmustine with bendamustine (BeEAM) was described as an alternative conditioning regimen in the autograft setting for patients with lymphoma. Several studies have reported inconsistent clinical outcomes comparing BeEAM and BEAM. Therefore, in the lack of well-designed prospective comparative studies, the comparison of BeEAM versus BEAM is based on retrospective trials. To compare the clinical outcomes between BeEAM and BEAM, we performed a meta-analysis of 10 studies which compared the outcomes between BeEAM and BEAM in patients autografted for lymphoma disease (HL or NHL). We searched article titles and compared transplantation with BeEAM versus BEAM in MEDLINE (PubMed), Cochrane library, and EMBASE database. Here, we report the results of nine main endpoints in our meta-analysis comparing BeEAM and BEAM, including neutrophil engraftment (NE), platelet engraftment (PE), overall survival (OS), progression free survival (PFS), non-relapse mortality (NRM), relapse rate (RR), grade 3 mucositis, renal toxicity, and cardiotoxicity. We discovered that the BeEAM regimen was associated with a slightly better PFS [pooled odds ratio (OR) of 0.70, 95% confidence interval (CI), 0.52-0.94, P = 0.02], lower RR (0.49, 95% CI, 0.31-0.76, P = 0.002), higher mucositis (3.43, 95% CI, 2.29-5.16, P = 0.001), renal toxicity (4.49, 95% CI, 2.68-7.51, P = 0.001), and cardiotoxicity (1.88, 95% CI, 1.03-3.40, P = 0.03). We also discovered that the two groups had equivalent NE (pooled WMD -0.64, 95% CI, -1.46 to 0.18, P = 0.13), PE (pooled WMD -0.3, 95% CI, -1.68 to 2.28, P = 0.77), OS (0.73, 95% CI, 0.52-1.01, P = 0.07), and NRM (1.51, 95% CI, 0.76-2.98, P = 0.24). The results of this meta-analysis show that the BeEAM regimen is a viable alternative to BEAM. More prospective comparisons between BeEAM and BEAM are required.

The Combination of Jiedu Xiaoluo Decoction with Autologous Peripheral Blood Stem Cell Transplantation (APBSCT) Accelerates Disease Remission of Non-Hodgkin Lymphoma

Objective

This study aimed to explore the therapeutic effects of autologous peripheral blood stem cell transplantation (APBSCT) with Jiedu Xiaoluo decoction (JDX) on non-Hodgkin lymphoma (NHL).

Method

B lymphoma cells A20 were used to establish nude mice-transplanted tumor model. The peripheral blood of mice was analyzed by automatic blood cell counter. Inflammatory cytokines in tumor tissues were measured by ELISA, real-time qRT-PCR, and western blotting assays. Immunohistochemical staining was employed to evaluate tumor cell growth and apoptosis. CCK8 and Transwell assays were used to detect cell viability, migration, and invasion. Cell apoptosis in vitro was evaluated with flow cytometry.

Result

In the in vitro co-culture system of A20 cells and hemopoietic stem cells (HSC), JDX notably inhibited the proliferation, migration, and invasion and promoted apoptosis of A20 cells compared to HSC treatment alone. In animal tumor xenografts of NHL, the combination of APBSCT with JDX significantly promoted hematopoietic reconstitution, inhibited tumorigenesis of A20 cell, promoted the inflammatory microenvironment remission, inhibited cell proliferation, and promoted apoptosis compared to APBSCT alone.

Conclusion

The combination of APBSCT with JDX might be an effective strategy to treat NHL through inhibiting tumorigenesis and reconstructing hematopoietic and immune microenvironment. Our finding provided a novel insight into the clinical application of Traditional Chinese Medicine (TCM) against NHL.

High-dose etoposide could discriminate the benefit from autologous peripheral blood stem cell transplantation in the patients with refractory diffuse large B cell lymphoma

To evaluate the strategy of using high-dose etoposide mobilization followed by autologous peripheral blood stem cell transplantation (APBSCT) in patients with diffuse large B cell lymphoma (DLBCL) refractory to rituximab-based chemotherapy. Forty patients with refractory DLBCL were treated with high-dose etoposide for stem cell mobilization. All patients were in progressive disease (PD) prior to mobilization and underwent high-dose chemotherapy followed by APBSCT. Successful PBSC mobilization was achieved in all patients. Twenty-three patients (57.5%) showed a clinical response to high-dose etoposide. After APBSCT, 17 patients (42.5%) achieved CR. The 2-year progression-free (PFS) and overall survival (OS) rate were higher in patients responding to high-dose etoposide (64.1% and 77.7%) compared to those without response (11.8% and 11.8%; P < 0.001 for both). The response to high-dose etoposide mobilization therapy was an independent prognostic factor for CR achievement, PFS and OS after APBSCT. High-dose etoposide mobilization chemotherapy followed by APBSCT could rescue a proportion of patients with refractory DLBCL who responded to etoposide mobilization regimen.

Bendamustine-based conditioning prior to autologous stem cell transplantation (ASCT): Results of a French multicenter study of 474 patients from LYmphoma Study Association (LYSA) centers

Carmustine shortage has led to an increase use of alternative conditioning regimens prior to autologous stem cell transplantation for the treatment of lymphoma, including Bendamustine-based (BeEAM). The aim of this study was to evaluate the safety of the BeEAM regimen in a large cohort of patients. A total of 474 patients with a median age of 56 years were analyzed. The majority of patients had diffuse large B-cell lymphoma (43.5%). Bendamustine was administered at a median dose of 197 mg/m² /day (50-250) on days-7 and -6. The observed grade 1-4 toxicities included mucositis (83.5%), gastroenteritis (53%), skin toxicity (34%), colitis (29%), liver toxicity (19%), pneumonitis (5%), and cardiac rhythm disorders (4%). Nonrelapse mortality (NRM) was reported in 3.3% of patients. Acute renal failure (ARF) was reported in 132 cases (27.9%) (G ≥2; 12.3%). Organ toxicities and death were more frequent in patients with post conditioning renal failure. In a multivariate analysis, pretransplant chronic renal failure, bendamustine dose >160 mg/m² and age were independent prognostic factors for ARF. Pretransplant chronic renal failure, hyperhydration volume, duration of hyperhydration, and etoposide dose were predictive factors of NRM. A simple, four-point scoring system can stratify patients by levels of risk for ARF and may allow for a reduction in the bendamustine dose to avoid toxicity. Drugs shortage may have dangerous consequences. Prospective, comparative studies are needed to confirm the toxicity/efficacy extents from this conditioning regimen compared to other types of high dose therapy.

In Silico Evaluation of Pharmacokinetic Optimization for Antimitogram-Based Clinical Trials

Antimitograms are prototype in vitro tests for evaluating chemotherapeutic efficacy using patient-derived primary cancer cells. These tests might help optimize treatment from a pharmacodynamic standpoint by guiding treatment selection. However, they are technically challenging and require refinements and trials to demonstrate benefit to be widely used. In this study, we performed simulations aimed at exploring how to validate antimitograms and how to complement them by pharmacokinetic optimization. A generic model of advanced cancer, including pharmacokinetic-pharmacodynamic monitoring, was used to link dosing schedules with progression-free survival (PFS), as built from previously validated modules. This model was used to explore different possible situations in terms of pharmacokinetic variability, pharmacodynamic variability, and antimitogram performance. The model recapitulated tumor dynamics and standalone therapeutic drug monitoring efficacy consistent with published clinical results. Simulations showed that combining pharmacokinetic and pharmacodynamic optimization should increase PFS in a synergistic fashion. Simulated data were then used to compute required clinical trial sizes, which were 30% to 90% smaller when pharmacokinetic optimization was added to pharmacodynamic optimization. This improvement was observed even when pharmacokinetic optimization alone exhibited only modest benefit. Overall, our work illustrates the synergy derived from combining antimitograms with therapeutic drug monitoring, permitting a disproportionate reduction of the trial size required to prove a benefit on PFS. Accordingly, we suggest that strategies with benefits too small for standalone clinical trials could be validated in combination in a similar manner.Significance: This work offers a method to reduce the number of patients needed for a clinical trial to prove the hypothesized benefit of a drug to progression-free survival, possibly easing opportunities to evaluate combinations. Cancer Res; 78(7); 1873-82. ©2018 AACR.

Development of a Limited Sampling Strategy for the Estimation of Exposure to High-Dose Etoposide After Intravenous Infusion in Pediatric Patients

BACKGROUND

Etoposide (VP-16), a podophyllotoxin derivative, is used in conditioning regimens before allogeneic hematopoietic stem cell transplantation in children with acute lymphoblastic leukemia. The aim of this study was to develop a limited sampling strategy (LSS) suitable for the prediction of exposure to VP-16 defined as area under time-concentration curve (AUC).

METHODS

The study included 28 pediatric patients with acute lymphoblastic leukemia, who were administered a 4-hour infusion of 60 mg/kg VP-16. VP-16 concentrations were determined in samples collected 4-124 hours after the beginning of infusion. On obtaining the pharmacokinetic (PK) profiles, a population PK model was developed in NONMEM (ICON Development Solutions, Hanover, MD) with first-order conditional estimation with interaction algorithm. LSSs were chosen by means of a multivariate regression analysis and cross-validated with a leave-one-out approach. Predictive performance of LSSs was assessed by calculating relative prediction error (PE), mean PE, mean absolute PE, and root mean squared PE for model-predicted and observed AUC.

RESULTS

VP-16 PKs was best described by a 2-compartment first-order model, and a large variability in the PK parameters was observed. A 3-sample strategy allowed the estimation of VP-16 with highest accuracy and precision (mean relative PE = 0.18%, 95% confidence interval, 1.73%-2.09%; mean absolute relative PE = 3.47%, 95% confidence interval, 2.28%-4.66%; root mean squared PE = 4.43%). The final equation was AUC = 6.85 × C6 h + 3.88 × C12 h + 46.11 × C28 h + 282.0 (adjusted R = 0.9540).

CONCLUSIONS

In conclusion, developed LSS allows accurate and precise estimation of VP-16 AUC and might be useful for therapeutic drug monitoring.

Pharmacokinetics and dose adjustment of etoposide administered in a medium-dose etoposide, cyclophosphamide and total body irradiation regimen before allogeneic hematopoietic stem cell transplantation

BACKGROUND

We investigated the pharmacokinetics of etoposide (ETP) to reduce the inter-individual variations of ETP concentrations in patients with acute leukemia who underwent allogeneic hematopoietic stem cell transplantation. We also carried out an in vivo study using rats to verify the dose adjustment.

METHODS

This study included 20 adult patients. ETP was administered intravenously at a dose of 15 mg/kg once daily for 2 days (total dose: 30 mg/kg) combined with standard conditioning of cyclophosphamide and total body irradiation. In an in vivo study using rats, ETP was administered intravenously at a dose of 15 mg/kg or an adjusted dose. The ETP plasma concentration was determined by using HPLC. The pharmacokinetic parameters were estimated by using a 1-compartment model.

RESULTS

The peak concentration (Cmax) of ETP and the area under the plasma concentration-time curve (AUC) of ETP differed greatly among patients (range of Cmax, 51.8 - 116.5 μg/mL; range of AUC, 870 - 2015 μg · h/mL). A significant relationship was found between Cmax and AUC (R = 0.85, P < 0.05). Distribution volume (Vd) was suggested to be one of the factors of inter-individual variation in plasma concentration of ETP in patients (range of Vd, 0.13 - 0.27 L/kg), and correlated with Alb and body weight (R = 0.56, P < 0.05; R = 0.40, P < 0.05 respectively). We predicted Vd of rats by body weight of rats (with normal albumin levels and renal function), and the dose of ETP was adjusted using predicted Vd. In the dose adjustment group, the target plasma ETP concentration was achieved and the variation of plasma ETP concentration was decreased.

CONCLUSION

The results suggested that inter-individual variation of plasma concentration of ETP could be reduced by predicting Vd. Prediction of Vd is effective for reducing individual variation of ETP concentration and might enable a good therapeutic effect to be achieved.