Concurrent Imatinib Dosing With High-dose Methotrexate Leads to Acute Kidney Injury and Delayed Methotrexate Clearance in Pediatric Patients With Philadelphia Chromosome-positive B-Cell Acute Lymphoblastic Leukemia

Early clinical indicators of acute kidney injury caused by administering high-dose methotrexate therapy to juvenile pigs

Introduction

Early identification of compromised renal clearance caused by high-dose methotrexate (HDMTX) is essential for initiating timely interventions that can reduce acute kidney injury and MTX-induced systemic toxicity.

Methods

We induced acute kidney injury (AKI) by infusing 42 juvenile pigs with 4 g/kg (80 g/m2) of MTX over 4 hours without high-volume alkalinizing hydration therapy. Concentrations of serum creatinine and MTX were measured at 15 time points up to 148 hours, with 10 samples collected during the first 24 hours after the start of the HDMTX infusion.

Results

During the first 28 hours, 81% of the pigs had increases in the concentrations of serum creatinine in one or more samples indicative of AKI (i.e., > 0.3g/dL increase). A rate of plasma MTX clearance of less than 90% during the initial 4 hours after the HDMTX infusion and a total serum creatinine increase at 6 and 8 hours after starting the infusion greater than 0.3 g/dL were predictive of AKI at 28 hours (p < 0.05 and p < 0.001, respectively). At conclusion of the infusion, pigs with a creatinine concentration more than 0.3 g/dL higher than baseline or serum MTX greater than 5,000 μmol/L had an increased risk of severe AKI.

Conclusions

Our findings suggest that serum samples collected at conclusion and shortly after HDMTX infusion can be used to predict impending AKI. The pig model can be used to identify biological, environmental, and iatrogenic risk factors for HDMTX-induced AKI and to evaluate interventions to preserve renal functions, minimize acute kidney injury, and reduce systemic toxicity.

Acute kidney injury and delayed methotrexate clearance in an adult patient with Philadelphia chromosome-positive acute lymphoblastic leukaemia treated with imatinib

A female patient in her early 30s was treated with imatinib and high-dose methotrexate (HD-MTX) for Philadelphia chromosome-positive acute lymphoblastic leukaemia. The patient developed delayed MTX clearance and grade 3 acute kidney injury characterised by elevated creatinine (114% increase from baseline). After intensified calcium folinate rescue therapy and hydration, the MTX serum level was appropriately decreased 72 hours after the start of MTX infusion, and renal function returned to normal. Medication analysis by a clinical pharmacist suggested that the concomitant treatment with imatinib likely contributed to the delayed MTX clearance and caused the acute kidney injury.

A high-throughput UPLC-MS/MS method for the determination of eight anti-tumor drugs in plasma

Rapidly developing UPLC-MS/MS bioassays with high throughput and quality are challenging yet desired in routine clinics. METHODS & RESULTS: A high-throughput UPLC-MS/MS bioassay has been built for simultaneously quantifying gefitinib, ruxolitinib, dasatinib, imatinib, ibrutinib, methotrexate, cyclophosphamide and paclitaxel. After the protein precipitation with methanol, samples were separated on an Acquity BEH C₁₈ column following a gradient elution system with methanol and 2 mM ammonium acetate in water at 40 °C with a run time of 3 min (flow rate 0.4 mL/min). Mass quantification in the positive ion SRM mode was then performed with electrospray ionization. The method of specificity, linearity, accuracy, precision, matrix effects, recovery, stability, dilution integrity and carryover were all validated as per the guideline of the China Food and Drug Administration whose values met the admissible limits. Application of the bioassay to therapeutic drug monitoring revealed important variability in the studied anti-tumour drugs. CONCLUSION: This validated approach was shown to be reliable and effective in clinical management, being a valuable support in therapeutic drug monitoring and subsequent individualized dosing optimization.

A critical review of methotrexate clinical interactions: role of transporters

INTRODUCTION

Methotrexate (MTX) is an anti-folate and immunosuppressive drug prescribed for various malignancies and immune diseases. However, delayed elimination of MTX associated with concomitant use of some medications can lead to severe and life-threatening adverse effects.

AREAS COVERED

This paper investigated drug-MTX interactions that lead to elevated MTX levels and related adverse effects due to the role of transporters. Methotrexate toxicity occurs at both low and high doses administrations. According to the studies we reviewed in this paper, most interaction records with methotrexate occurred with co-administration of indomethacin, ketoprofen, omeprazole, piperacillin/tazobactam, ciprofloxacin, co-trimoxazole, probenecid, and imatinib, mainly due to the role of transporters. However, most studies were performed as case reports or series, and confirming the exact drug-methotrexate interaction still needs further clinical investigations.

EXPERT OPINION

Our findings showed no firm evidence of interactions of proton pump inhibitors (PPIs), levetiracetam, and NSAIDS with MTX. Moreover, patients' risk factors, hypoalbuminemia, renal failure, third space fluid retention, the elderly, polypharmacy, and transport inhibition are the most critical factors for MTX toxicity. If substitution or temporary discontinuation is not possible, healthcare providers should be aware of interactions, especially in patients with risk factors for MTX toxicity.

Insights from a pharmacometric analysis of HDMTX in adults with cancer: Clinically relevant covariates for application in precision dosing

AIMS

High-dose methotrexate (HDMTX) is an essential part of the treatment of several adult and paediatric malignancies. Despite meticulous supportive care during HDMTX administration, severe toxicities, including acute kidney injury (AKI), may occur contributing to patient morbidity. Population pharmacokinetics provide a powerful tool to predict time to clear HDMTX and adjust subsequent doses. We sought to develop and validate pharmacokinetic models for HDMTX in adults with diverse malignancies and to relate systemic exposure with the occurrence of severe toxicity.

METHODS

Anonymized, de-identified data were provided from 101 US oncology practices that participate in the Guardian Research Network, a non-profit clinical research consortium. Modelled variables included clinical, laboratory, demographic and pharmacological data. Population pharmacokinetic analysis was performed by means of nonlinear mixed effects modelling using MonolixSuite.

RESULTS

A total of 693 HDMTX courses from 243 adults were analysed, of which 62 courses (8.8%) were associated with stage 2/3 acute kidney injury (43 stage 2, 19 stage 3). A three-compartment model adequately fitted the data. Time-dependent serum creatinine, baseline serum albumin and allometrically scaled bodyweight were clinically significant covariates related to methotrexate clearance. External evaluation confirmed a satisfactory predictive performance of the model in adults receiving HDMTX. Dose-normalized methotrexate concentration at 24 and 48 hours correlated with AKI incidence.

CONCLUSION

We developed a population pharmacometric model that considers weight, albumin and time-dependent creatinine that can be used to guide supportive care in adult patients with delayed HDMTX elimination.

Metabolic profiling reveals metabolic features of consolidation therapy in pediatric acute lymphoblastic leukemia

Acute lymphoblastic leukemia (ALL) and its treatment continue to pose substantial risks. To understand ALL more deeply, the metabolome in fasting plasma of 27 ALL patients before and after high-dose methotrexate therapies (consolidation therapy) including methotrexate and 6-mercaptopurine (6-MP) was investigated. Plasma metabolites were analyzed using liquid chromatography-tandem mass spectrometry (LC-MS). Orthogonal projections to latent structures discriminant analysis and significance analysis of microarrays were used to evaluate the metabolic changes. Pathway enrichment and co-expression network analyses were performed to identify clusters of molecules, and 2826 metabolites were identified. Among them, 38 metabolites were identified by univariate analysis, and 7 metabolites that were altered by conditioning therapy were identified by multivariate analysis. The Kyoto Encyclopedia of Genes and Genomes (KEGG) database was used for pathway enrichment analysis. Among the enriched KEGG pathways, the 3 significantly altered metabolic pathways were pyrimidine metabolism; phenylalanine, tyrosine, and tryptophan biosynthesis; and phenylalanine metabolism. In addition, L-phenylalanine was significantly correlated with blood urea nitrogen (BUN), and palmitoylcarnitine was correlated with aspartate aminotransferase (AST). In summary, consolidation therapy significantly affected pyrimidine- and phenylalanine-associated metabolic pathways in pediatric ALL patients. These findings may provide an insight into the role of metabolic profiling in consolidation treatment and as a potential for pediatric ALL patients.

Effects of genetic polymorphisms on methotrexate levels and toxicity in Chinese patients with acute lymphoblastic leukemia

Methotrexate (MTX) has an antitumor effect when used for the treatment of acute lymphoblastic leukemia (ALL). This study aims at evaluating the associations between 14 polymorphisms of six genes involved in MTX metabolism with serum MTX concentration and toxicity accompanying high-dose MTX. Polymorphisms in 183 Chinese patients with ALL were analyzed using TaqMan single nucleotide polymorphism genotyping assay. The serum MTX concentration was determined using homogeneous enzyme immunoassay. MTX-related toxicities were also evaluated. Renal toxicity was significantly associated with higher serum MTX concentrations at 24, 48, and 72 hours, and MTX elimination delay (P = 0.001, P < 0.001, P < 0.001, and P < 0.001, respectively), whereas SLCO1B1 rs4149056 was associated with serum MTX concentrations at 48 and 72 hours, and MTX elimination delay in candidate polymorphisms (P = 0.014, P = 0.019, and P = 0.007, respectively). SLC19A1 rs2838958 and rs3788200 were associated with serum MTX concentrations at 24 hours (P = 0.016, P = 0.043, respectively). MTRR rs1801394 was associated with serum MTX concentrations at 72 hours (P = 0.045). Neutropenia was related to SLC19A1 rs4149056 (odds ratio [OR]: 3.172, 95% confidence interval [CI]: 1.310-7.681, P = 0.011). Hepatotoxicity was associated with ABCC2 rs2273697 (OR: 3.494, 95% CI: 1.236-9.873, P = 0.018) and MTRR rs1801394 (OR: 0.231, 95% CI: 0.084-0.632, P = 0.004). Polymorphisms of SLCO1B1, SLC19A1, ABCC2, and MTRR genes help predict higher risk of increased MTX levels or MTX-related toxicities in adult ALL patients.

A simple isotope-labeled UHPLC-MS/MS assay for simultaneous quantification of methotrexate, imatinib and dasatinib

Aim: To assist therapeutic dose adjustment in clinic, a reliable concentration measurement is quite necessary for therapeutic drug monitoring. Results: A UHPLC-MS/MS bioassay for simultaneous determination of methotrexate, imatinib and dasatinib using isotope dilution internal standardization has been established and fully validated as per China Food and Drug Administration guideline. After a simple protein precipitation, the analytes were separated by a gradient elution within 3 min and mass detection was performed via ESI+ mode with SRM. The calibration curves were in the range of 5-100 ng/ml for methotrexate, 25-5000 ng/ml for imatinib and 1-250 ng/ml for dasatinib. Imprecision and inaccuracy values were ≤9.44% and ≤12.81% for all analytes, respectively. Conclusion: The developed method is appropriate for therapeutic drug monitoring, being applied to help individualized therapy in patients with acute lymphoblastic leukemia.

Standardized Supportive Care Documentation Improves Safety of High-Dose Methotrexate Treatment

BACKGROUND

High-dose (HD) methotrexate (MTX) is an essential component of treatment protocols in acute lymphoblastic leukemia, aggressive lymphoma, and osteosarcoma. However, delayed MTX clearance may lead to life-threatening toxicities. Administration of supportive therapy for HD-MTX is complex, and insufficient supportive care increases the risk of MTX toxicity. To improve patient safety, we investigated the implementation of a checklist and urine alkalinization protocol in addition to standard supportive care during HD-MTX therapy.

MATERIALS AND METHODS

The intervention included individualized patient checklists for control of adequate supportive care for every HD-MTX treatment cycle and a urine alkalinization protocol for documentation and guidance during urine alkalinization therapy. The impact of these tools on the rate of adverse events (acute renal injury, delayed MTX clearance) was retrospectively assessed in patients treated from April 2017 to April 2019 (intervention group) and compared with patients treated from January 2015 to March 2017 who received standard supportive care for HD-MTX according to a standard operating procedure (SOP).

RESULTS

In total, 118 patients received 414 HD-MTX cycles in the intervention group compared with 108 patients with 332 treatment cycles in the SOP group. Delayed MTX clearance was observed in 2.6% of treatment cycles in the intervention cohort opposed to 15.2% of cycles in the SOP group. The rate of acute kidney injury was also significantly reduced in the intervention group (6.2%. vs. 0.7%). The use of carboxypeptidase as rescue treatment for severe renal impairment and insufficient MTX clearance was necessary in five cases in the SOP group and in only two cycles within the intervention group.

CONCLUSION

The use of standardized documentation for supportive care during HD-MTX therapy is recommended to minimize the risk of adverse events.

IMPLICATIONS FOR PRACTICE

High-dose methotrexate (HD-MTX) is a commonly used treatment in several cancer types. Distinct supportive measures are necessary to minimize the risk of HD-MTX side effects, which can be life-threatening. Supportive care consists of certain examinations and interventions before starting HD-MTX and permanent alkalinization of the urine, as this greatly increases the elimination of MTX and decreases the risk of kidney injury. After implementing a checklist for control of supportive care and a urine alkalinization protocol to optimize urine alkalinization, a significant decrease of side effects was observed in comparison to the standard of care; therefore, the use of a safety checklist and alkalinization protocol is recommended for all patients who receive HD-MTX.