A liquid chromatography-tandem mass spectrometry method for the simultaneous quantification of actinomycin-D and vincristine in children with cancer

Liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) methods for the therapeutic drug monitoring of cytotoxic anticancer drugs: An update

In the era of precision medicine, there is increasing evidence that conventional cytotoxic agents may be suitable candidates for therapeutic drug monitoring (TDM)- guided drug dosage adjustments and patient's tailored personalization of non-selective chemotherapies. To that end, many liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) assays have been developed for the quantification of conventional cytotoxic anticancer chemotherapies, that have been comprehensively and critically reviewed. The use of stable isotopically labelled internal standards (IS) of cytotoxic drugs was strikingly uncommon, accounting for only 48 % of the methods found, although their use could possible to suitably circumvent patients' samples matrix effects variability. Furthermore, this approach would increase the reliability of cytotoxic drug quantification in highly multi-mediated cancer patients with complex fluctuating pathophysiological and clinical conditions. LC-MS/MS assays can accommodate multiplexed analyses of cytotoxic drugs with optimal selectivity and specificity as well as short analytical times and, when using stable-isotopically labelled IS for quantification, provide concentrations measurements with a high degree of certainty. However, there are still organisational, pharmacological, and medical constraints to tackle before TDM of cytotoxic drugs can be more largely adopted in the clinics for contributing to our ever-lasting quest to improve cancer treatment outcomes.

Simultaneous quantification and pharmacokinetics of vincristine and its major metabolite M1 in Chinese pediatric ALL patients by LC-MS/MS

Vincristine (VCR) is a vital component in numerous treatment regimens for pediatric blood cancer. VCR-induced peripheral neuropathy (VIPN) represents a type of VCR toxicity influenced by multiple factors, including age, race, genetic traits, dosage, interactions, and administration regimen. However, the dose-response relationship of VIPN remains elusive. VCR is primarily metabolized by cytochrome P450 (CYP) 3 A to generate the major metabolite M1. To date, there is a lack of literature documenting the pharmacokinetics (PK) characteristics of VCR and M1 in Chinese children within a 96 h timeframe. To address the gap, a developed LC-MS/MS method was successfully employed in the PK study of VCR and M1 in Chinese pediatric acute lymphoblastic leukemia (ALL) patients. M1 was obtained through in vitro metabolism experiments, and mixed plasma samples of M1 and VCR were prepared. Plasma samples were pre-processed using the solid-phase extraction (SPE) technique. Samples were loaded into ProElut C18 Cartridges, washed with 5% methanol aqueous solution, and eluted with methanol. The eluent was concentrated and reconstituted for liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. The standard calibration curves for VCR and M1 were 0.1-50 ng/mL and 0.05-5 ng/mL, respectively, with linear coefficients exceeding 0.99. Accuracy and precision of quality control (QC) samples fell within 115%. The analytical approach satisfied the quantitative demands for VCR and M1 in plasma samples within 96 h. VCR was metabolized to M1 at a relatively constant proportion (5.37%-18.06%) of VCR in vivo. No significant differences were observed in PK parameters of VCR in Chinese children compared to other countries and races. Further investigation is required to identify the key factors influencing VIPN in Chinese children.

A rapid and sensitive LC-ESI-MS/MS method for determining vincristine in micro-volumes of plasma for pediatric cancer patients

Vincristine is a natural vinca alkaloid drug, which is widely used in pediatric cancer treatment with dose-dependent neurotoxicity. Thus far, little is known about the association between neurotoxicity and plasma vincristine concentration, which markedly varies among individuals. Routine therapeutic drug monitoring (TDM) can be seen as a reliable strategy to improve efficacy and reduce side effects. Therefore, a rapid, sensitive, and reproducible method is critical for the clinical implementation of TDM. In this study, micro-volume (50 μL) human plasma samples were prepared by a simple one-step protein precipitation method with acetonitrile. Chromatographic separation of vincristine and its internal standard vincristine-d₃ from background noise was achieved on a Kinetex C18 column (2.1 mm × 50 mm, 1.7 μm) with a gradient elution program at a flow rate of 0.3 mL min^-1 in 4 min. The mass spectrometric detection was performed in electrospray ionization multiple reaction monitoring mode using the ion transitions of 825.4 → 765.1 for vincristine, and 828.2 → 768.2 for vincristine-d₃, respectively. As a result, no matrix effect was observed. The lower limit of quantification was 0.5 ng mL^-1 with a precision of 14.6% and an accuracy of 97.4%. The calibration curve was linear from 0.5 to 100 ng mL^-1 (r² > 0.99, n = 8). The intra- and inter-batch precision and accuracy, recovery, and stability of the new method were all within the acceptable criteria. The method was successfully applied to monitor the vincristine concentration for six pediatric cancer patients. Arguably, such proactive TDM of vincristine may be helpful to manage the treatment for these cancer patients.

Toxicity and pharmacokinetics of actinomycin-D and vincristine in children and adolescents: Children's Oncology Group Study ADVL06B1

Actinomycin-D and vincristine are cytotoxic drugs commonly used to treat cancers in children. This prospective study assessed pharmacokinetic variability and toxicity of these drugs in children. Blood samples were collected in 158 patients. Actinomycin-D or vincristine concentrations were quantified using high-performance liquid chromatography-tandem mass spectrometry. Pharmacokinetic parameters were estimated using non-compartmental methods. Target toxicities were collected prospectively. Actinomycin-D pharmacokinetics (n = 52 patients) were highly variable. The median (coefficient of variation, CV%) area under the concentration-time curve (AUC) was 332 ng/mL·h. (110%); clearance was 4.6 L/h/m² (90%); half-life was 25 h (60%). No patient met the defined criteria for myelosuppression. In multivariate analysis, none of the demographic nor pharmacokinetic parameters was predictors of acute hepatotoxicity. Vincristine pharmacokinetics (n = 132 patients) demonstrated substantial variability. The median (CV%) AUC was 78 ng/mL·h (98%); clearance was 17.2 L/h/m² (67%); half-life was 14.6 h (73%). In multivariate analysis, the effect of increasing age for a given BSA was an increase in neuropathy while the effect of increasing BSA for a given age was a decrease in neuropathy. Conclusion: Pharmacokinetics of both drugs were highly variable. For actinomycin-D, there was no correlation between demographic or pharmacokinetic parameters and target toxicities. For vincristine, the correlations of age and BSA and neuropathy are confounded by the correlation between age and BSA in children and the ability to ascertain neuropathy in infants. Variability may be attributed to dose reductions and capped doses for both drugs. Investigation of BSA-based dosing in young children is warranted to decrease variability of exposure.

Population pharmacokinetic model development and exposure-response analysis of vincristine in patients with malignant lymphoma

PURPOSE

Vincristine (VCR) is a key drug for treating various malignancies. However, few data are available on the pharmacokinetics of VCR, especially in adult patients. The objective of this study was to clarify the population pharmacokinetics and exposure-response relationships of VCR in adult malignant lymphoma patients.

METHODS

Blood samples were collected from patients who were administered R-CHOP-like regimens, and the VCR plasma concentration was determined using liquid chromatography-mass spectrometry. Using NONMEM software, population pharmacokinetic parameters were estimated, and covariates were evaluated. The relationships between the individual parameters and adverse events or therapeutic effects were also investigated.

RESULTS

Plasma concentrations were measured in 30 patients. In the final population pharmacokinetics model, body surface area and age were incorporated into clearance as significant covariates. The inter-individual variations in clearance and volume of distribution in the central and third compartments were 17.0, 26.6, and 66.3%, respectively, and the residual variability in the plasma concentration was 23.8%. Although the variability observed in the volume of distribution was large, good predictability was obtained in the individual estimation. The severity of anemia and peripheral neuropathy was correlated with clearance and peak concentration, respectively (adjusted P = 0.040 and 0.024, respectively). In diffuse large B cell lymphoma patients, those with higher area under the curve and dose experienced longer progression-free survival (P = 0.023 and 0.013, respectively).

CONCLUSION

The population pharmacokinetics of VCR were evaluated in adult malignant lymphoma patients. VCR pharmacokinetic data could explain in part the adverse events and prognosis of these patients.

Mass spectrometry in the pharmacokinetic studies of anticancer natural products

In the history of medicine, nature has represented the main source of medical products. Indeed, the therapeutic use of plants certainly goes back to the Sumerian and Hippocrates and nowadays nature still represents the major source for new drugs discovery. Moreover, in the cancer treatment, drugs are either natural compounds or have been developed from naturally occurring parent compounds firstly isolated from plants and microbes from terrestrial and marine environment. A critical element of an anticancer drug is represented by its severe toxicities and, after administration, the drug concentrations have to remain in an appropriate range to be effective. Anyway, the drug dosage defined during the clinical studies could be inappropriate for an individual patient due to differences in drug absorption, metabolism and excretion. For this reason, personalized medicine, based on therapeutic drug monitoring (TDM), represents one of most important challenges in cancer therapy. Mass spectrometry sensitivity, specificity and fastness lead to elect this technique as the Golden Standard for pharmacokinetics and drug metabolism studies therefore for TDM. This review focuses on the mass spectrometry-based methods developed for pharmacokinetic quantification in human plasma of anticancer drugs derived from natural sources and already used in clinical practice. Particular emphasis was placed both on the pre-analytical and analytical steps, such as: sample preparation procedures, sample size required by the analysis and the limit of quantification of drugs and metabolites to give some insights on the clinical practice applicability. © 2015 Wiley Periodicals, Inc. Mass Spec Rev. 36:213-251, 2017.

Antineoplastic drugs and their analysis: a state of the art review

We provide an overview of the analytical methods available for the quantification of antineoplastic drugs in pharmaceutical formulations, biological and environmental samples.

Clinical pharmacokinetics and effects of vincristine sulfate in dogs with transmissible venereal tumor (TVT)

This study was conducted to evaluate the pharmacokinetic characteristics of vincristine and their correlation with its clinical effects in dogs with transmissible venereal tumor (TVT). Dogs with TVT were intravenously administered vincristine sulfate at a dose of 0.7 mg/m(2) of body surface area. Blood samples were collected starting from 5 min to 48 hr after drug administration. The plasma concentration of vincristine was determined using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The pharmacokinetic parameters of vincristine were characterized using a two-compartmental pharmacokinetic model. The volume of distribution, distribution half-life, elimination half-life and plasma clearance were 0.660 ± 0.210 l/kg, 21.5 ± 6.90 min, 47.6 ± 14.2 min and 0.010 ± 0.001 l/min/kg, respectively. Tumor regression was determined at weekly interval by a physical examination and histopathological analysis. In our study, three to eight administrations of vincristine at a dose of 0.7 mg/m(2) were able to induce a complete tumor regression without any evidence of gross lesion of disease. Therefore, this investigation provides the pharmacokinetic characteristics of vincristine in dogs with TVT, which may be used as an integration tool to gain a better understanding of the disposition properties of the drug and the correlation of these properties with the drug's clinical effects. In addition, we validated the LC-MS/MS method and found that it is suitable for the pharmacokinetic study of vincristine in dog plasma.

Pharmacokinetic evaluation of vincristine for the treatment of lymphoid malignancies

INTRODUCTION

Vincristine is a key agent for the treatment of acute lymphoblastic leukemia (ALL) and other lymphoid malignancies. The strong antineoplastic activity of vincristine has been limited by its pharmacological characteristics.

AREAS COVERED

This paper reviews the role of vincristine in the treatment of lymphoid malignancies. This review summarizes its efficacy and toxicity, and focuses on the pharmacokinetic features of vincristine that affect clinical outcomes.

EXPERT OPINION

As a single agent, vincristine is associated with brief and incomplete responses, but in combination with other agents, vincristine has dramatically improved the outcomes of lymphoid malignancies such as ALL. Vincristine is a key drug of hyper-fractionated cyclophosphamide, vincristine, doxorubicin and dexamethasone, an intensive chemotherapeutic regimen for the treatment of ALL, and of cyclophosphamid, adriamycin, vincristine and prednisone, which has been used extensively in the treatment of patients with aggressive or indolent lymphomas and Richter syndrome. The strong antileukemic activity of vincristine has been limited by its variable and unpredictable pharmacological characteristics, narrow therapeutic index and neurotoxicity profile. These characteristics prompted the development of liposomal vincristine, which has optimized its clinical application. Liposomal vincristine has promising antileukemic activity, and it is approved by the FDA as a single agent for the treatment of relapsed/refractory Philadelphia chromosome-negative ALL.

Leaf extract from Clusia nemorosa induces an antinociceptive effect in mice via a mechanism that is adrenergic systems dependent

Previous studies on the genus Clusia have shown anti-inflammatory and antiproliferative effects of the leaf extracts, but its antinociceptive activity has never been characterized. In the present study, the antinociceptive activity of the hexane extract of the leaves of Clusia nemorosa G. Mey, called HECn, was examined. Antinociceptive activity was evaluated using acetic acid-induced writhing, formalin, and hot-plate tests. All experiments were carried out on male Swiss mice. The extract (1-400 mg·kg(-1)), given by intraperitoneal route (i.p.) 1 h prior to testing, produced a dose-dependent inhibition on the number of abdominal writhings, with an ID50 of 62 mg·kg(-1). In addition, HECn was able to prevent the visceral pain induced by acetic acid in mice for at least 2 h. In the formalin test, HECn had no effect in the first phase, but produced an analgesic effect on the second phase with the inhibition of licking time. The HECn did not show a significant analgesic effect in the hot plate test. Pretreatment with yohimbine attenuated the antinociceptive effect induced by HECn in the writhing test. However, naloxone, atropine, or haloperidol did not affect antinociception induced by HECn in the writhing test. Together, these results indicate that the extract from the leaves of Clusia nemorosa produces antinociception in models of chemical pain through mechanisms that suggest participation of the adrenergic systems pathway.

A novel submicron emulsion system loaded with vincristine-oleic acid ion-pair complex with improved anticancer effect: in vitro and in vivo studies

Background

Vincristine (VCR), which is a widely used antineoplastic drug, was integrated with a submicron-emulsion drug-delivery system to enhance the anticancer effect.

Methods

After the formation of a VCR-oleic acid ion-pair complex (VCR-OA), the VCR-OA-loaded submicron emulsion (VCR-OA-SME), prepared by classical high-pressure homogenization, was characterized and its in vitro anticancer effects were evaluated.

Results

The submicron-emulsion formulation exhibited a homogeneous round shape. The mean particle size, zeta potential, and encapsulation efficiency were 157.6 ± 12.6 nm, −26.5 ± 5.0 mV and 78.64% ± 3.44%, respectively. An in vitro release study of the VCR-OA-SME revealed that 12.4% of the VCR was released within the first 2 hours (initial burst-release phase) and the rest of the drug was detected in the subsequent sustained-release phase. Compared with VCR solution, the pharmacokinetic study of VCR-OA-SME showed relatively longer mean residence time (mean residence time [0–∞] increased from 187.19 to 227.56 minutes), higher maximum concentration (from 252.13 ng/mL to 533.34 ng/mL), and greater area under the curve (area under the curve [0–∞] from 11,417.77 μg/L/minute to 17,164.34 μg/L/minute. Moreover, the VCR-OA-SME exhibited higher cytotoxicity (P < 0.05) on tumor cells by inducing cell arrest in the G2/M phase or even apoptosis (P < 0.05).

Conclusion

The VCR-OA-SME formulation in our study displayed great potential for an anticancer effect for VCR.

Analysis of anticancer drugs: a review

In the last decades, the number of patients receiving chemotherapy has considerably increased. Given the toxicity of cytotoxic agents to humans (not only for patients but also for healthcare professionals), the development of reliable analytical methods to analyse these compounds became necessary. From the discovery of new substances to patient administration, all pharmaceutical fields are concerned with the analysis of cytotoxic drugs. In this review, the use of methods to analyse cytotoxic agents in various matrices, such as pharmaceutical formulations and biological and environmental samples, is discussed. Thus, an overview of reported analytical methods for the determination of the most commonly used anticancer drugs is given.

Microassay of drugs and modern measurement techniques

Details of the development of conventional analytical methods for the determination of drugs in pediatric plasma/serum samples via microassays are presented. Examples of the development of small-volume sampling and the use of the newer detection systems such as LC/MS/MS for enhanced detection are presented. Dried blood spot sampling has conventionally been used for the study of inborn errors of metabolism using Guthrie cards. Limited applications in the area of drug-level determination, for example, in therapeutic drug monitoring had been reported but the methodology had not been widely used up until relatively recently. In the last few years, there has been a resurgence of interest in this methodology for drug-level determinations, and examples of drug analysis in pediatric and neonatal patients where the small-volume samples are particularly useful are presented. The application of the methodology in pharmacokinetic/pharmacodynamic studies is discussed. The utilization of solid-phase microextraction and stir bar sorptive extraction in drug analysis is presented. Clinical applications of these methodologies are reported including the development of in vivo solid-phase microextraction.

Diet-induced obesity alters vincristine pharmacokinetics in blood and tissues of mice

Obesity is associated with poorer outcome from many cancers, including leukemia. One possible contributor to this could be suboptimal chemotherapy dosing in obese patients. We have previously found that vincristine (VCR) is less effective in obese compared to non-obese mice with leukemia, despite weight-based dosing. In the present study, we administered (3)H-VCR to obese and control mice to determine whether obesity would cause suboptimal VCR exposure. Blood VCR concentrations were fitted with a three-compartment model using pharmacokinetic analysis (two-stage PK) in three subsets of VCR concentrations vs. time method. Tissue and blood VCR concentrations were also analyzed using non-compartmental modeling. Blood VCR concentrations showed a triexponential decay and tended to be slightly higher in the obese mice at all time-points. However, the t(1/2,beta) and t(1/2,gamma) were shorter in the obese mice (9.7 min vs. 44.5 min and 60.3h vs. 85.6h, respectively), resulting in a lower AUC(0-infinity) (13,099 ng/m Lh vs. 15,384 ng/mL h). Had the dose of VCR been "capped", as is done in clinical practice, the AUC(0-infinity) would have been 36% lower in the obese mice than the controls. Tissue disposition of VCR revealed a biexponential decay from spleen, liver, and adipose. Interestingly, VCR slowly accumulated in the bone marrow of control mice, but had a slow decay from the marrow in the obese mice. Thus, obesity alters VCR PK, causing a lower overall exposure in circulation and bone marrow. Given the high prevalence of obesity, additional PK studies should be performed in obese subjects to optimize chemotherapy dosing regimens.

Validated assay for the simultaneous quantification of total vincristine and actinomycin-D concentrations in human EDTA plasma and of vincristine concentrations in human plasma ultrafiltrate by high-performance liquid chromatography coupled with tandem mass spectrometry

A sensitive, specific and efficient high-performance liquid chromatography/tandem mass spectrometry (HPLC/MS/MS) assay for the simultaneous determination of total vincristine and actinomycin-D concentrations in human plasma and an assay for the determination of unbound vincristine are presented. Electrospray ionization (ESI), atmospheric pressure chemical ionization (APCI) and heated electrospray ionization (H-ESI) were tested as ionization interfaces. For reasons of robustness ESI was chosen followed by tandem mass spectrometry (ESI-MS/MS). For the plasma assay a 30 microL aliquot was protein precipitated with acetonitrile/methanol (50:50, v/v) containing the internal standard vinorelbine and 10 microL volumes were injected onto the HPLC system. To determine unbound vincristine, ultrafiltrate was produced from plasma using 30 kDa centrifugal filter units. The plasma ultrafiltrate was mixed with methanol (50:50, v/v), internal standard vinorelbine was added and 20 microL aliquots were injected onto the HPLC system. Separation was achieved on a 50x2.1 mm i.d. Xbridge C18 column using 1 mM ammonium acetate/acetonitrile (30:70, v/v) adjusted to pH 10.5 with ammonia, run in a gradient with methanol at a flow rate of 0.4 mL/min. HPLC run time was 6 min. The assay quantifies in plasma vincristine from 0.25 to 100 ng/mL and actinomycin-D from 0.5 to 250 ng/mL using plasma sample volumes of only 30 microL. Vincristine in plasma ultrafiltrate can be quantified from 1 to 100 ng/mL. Validation results demonstrate that vincristine and actinomycin-D can be accurately and precisely quantified in human plasma and plasma ultrafiltrate with the presented methods. The assays are now in use to support clinical pharmacological studies in children treated with vincristine and actinomycin-D.

A sensitive and selective liquid chromatography-tandem mass spectrometry method for the simultaneous quantification of actinomycin-D and vincristine in children with cancer

We describe a selective and a highly sensitive assay for actinomycin-D (Act-D) and vincristine (VCR) in plasma employing high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) detection. The intraday precision (as defined by the coefficient of variation, CV) based on the standard deviation of replicates of quality control samples ranged from 4.9 to 7.5% and 6.5 to 11.3% with accuracy ranging from 90.7 to 98.1% and 91.2 to 103% for Act-D and VCR, respectively. The interday precision ranged from 7.2 to 10.0% and 11.3 to 13.0% and the accuracy ranged from 94.3 to 102% and 90.7 to 91.6% for Act-D and VCR, respectively. Stability studies showed that Act-D and VCR were stable both during the assay procedure and long-term storage. The lower limit of quantitation (LLOQ) for both Act-D and VCR was 0.05 ng/ml. The analytical method showed excellent sensitivity, precision, and accuracy. This method is robust and is being successfully employed in a pharmacokinetic study of these agents in children with cancer, and is expected to support several ongoing and future pediatric trials.