Development and clinical validation of a simple and fast UPLC-ESI-MS/MS method for simultaneous quantification of nine kinase inhibitors and two antiandrogen drugs in human plasma: Interest for their therapeutic drug monitoring

Dispersive liquid-liquid microextraction followed by sweeping micellar electrokinetic chromatography-tandem mass spectrometry for determination of six breast cancer drugs in human plasma

Herein, we have developed a novel method of aqueous-sample dispersive liquid-liquid microextraction (AqS-DLLME) followed by sweeping micellar electrokinetic chromatography-tandem mass spectrometry (MEKC-MS/MS) for simultaneous determination of breast cancer drugs letrozole, anastrozole, palbociclib, ribociclib, abemaciclib, and fulvestrant in human plasma. Coupling of MEKC to MS was possible due to the use of ammonium perfluorooctanoate (APFO) as a volatile surfactant. The MEKC and MS conditions were optimized to achieve a fast, sensitive, selective, and green analysis enabling full separation of the analytes within 16 min. Electrophoretic buffer was 125 mM APFO at apparent pH 10.5 in 32 % MeOH, while sheath liquid was 70 % MeOH with 0.2 % formic acid, delivered at 10 µL/min. Excellent extraction recoveries from plasma ranging from 89.4 to 104.9 % were obtained with a combination of protein precipitation and DLLME. The developed method was validated according to the ICH guidelines. Remarkable selectivity, accuracy (bias < 6.7 %), precision (RSD < 15.8 %), and stability (bias < 10.4 %) with insignificant matrix effect (RSD < 14.0 %) and no carry-over were obtained over a wide range of concentrations. Linearity with inter-day slope RSD lower than 8.7 % was demonstrated. With this method, very low concentrations could be detected after the injection of only 68.7 nL of the sample. The method was applied to plasma samples from six women currently receiving breast cancer treatment. Determined concentrations of the drugs of interest agreed with concentrations found in clinical studies, thus proving the suitability of the developed method for therapeutic drug monitoring as a superior alternative to published LC-MS methods.

Development and validation of a multiplex HPLC-MS/MS assay for the monitoring of JAK inhibitors in patient plasma

Janus kinase inhibitors (JAKi) are oral small molecules used in the treatment of a broad spectrum of autoimmune and myeloproliferative diseases. JAKi exhibit significant intra- and inter-individual pharmacokinetic variabilities, due to fluctuations in compliance with oral treatments and their metabolism essentially driven by cytochrome P450 enzymes. Intrinsically, JAKi have dose-response relationship and narrow therapeutic index: therapeutic drug monitoring (TDM) is expected to optimize and adapt their dosage regimen in order to resolve problems of efficacy and tolerance linked to dose and safety. A sensitive analytical method using multiplex high-performance liquid-chromatography coupled to tandem mass spectrometry (HPLC-MS/MS) was developed and validated for the simultaneous quantification in plasma of the 6 major currently used JAKi, namely abrocitinib, baricitinib, fedratinib, ruxolitinib, tofacitinib, and upadacitinib. Plasma samples are subjected to protein precipitation with MeOH, using stable isotopically labelled internal standards. The separation of JAKi in supernatants diluted 1:1 with ultrapure H2O was performed using a C18 column Xselect HSS T3 2.5 µm, 2.1x150 mm using a mobile phase composed of formic acid (FA) 0.2% and acetonitrile (+FA 0.1%) in gradient mode. The analytical run time for the multiplex assay was 7 min. JAKi drugs were monitored by electrospray ionization in the positive mode followed by triple-stage quadrupole MS/MS analysis. The method was validated according to SFSTP and ICH guidelines over the clinically relevant concentration ranges (0.5-200 ng/mL for abrocitinib, baricitinib and upadacitinib; 1-400 ng/mL for tofacitinib; 0.5-400 ng/mL for ruxolitinib, and 10-800 ng/mL for fedratinib). This multiplex HPLC-MS/MS assay achieved good performances in term of trueness (91.1-113.5%), repeatability (3.0-9.9%), and intermediate precision (4.5-11.3%). We developed and validated a highly sensitive method for the multiplex quantification of the JAKi abrocitinib, baricitinib, fedratinib, ruxolitinib, tofacitinib, and upadacitinib in human plasma. The method will be applied for prospective clinical pharmacokinetic studies to determine whether TDM programs for JAKi based on residual drug concentrations can be recommended using disease-specific therapeutic ranges.

Development of a UPLC-MS/MS method for simultaneous therapeutic drug monitoring of anti-hepatocellular carcinoma drugs and analgesics in human plasma

In hepatocellular carcinoma treatment, sorafenib, oxaliplatin, 5-fluorouracil, capecitabine, lenvatinib, and donafenib are first-line drugs; regorafenib, apatinib, and cabozantinib are second-line drugs; and oxycodone, morphine, and fentanyl are commonly used analgesics. However, the high degree of inter- and intra-individual variability in the efficacy and toxicity of these drugs remains an urgent issue. Therapeutic drug monitoring (TDM) is the most reliable technical means for evaluating drug safety and efficacy. Therefore, we developed an ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for simultaneous TDM of three chemotherapy drugs (5-fluorouracil, oxaliplatin, and capecitabin), six targeted drugs (sorafenib, donafenib, apatinib, cabozantinib, regorafenib, and lenvatinib), and three analgesics (morphine, fentanyl, and oxycodone). We extracted 12 analytes and isotope internal standards (ISs) from plasma samples by magnetic solid phase extraction (mSPE) and separated them using a ZORBAX Eclipse Plus C18 column with water containing 0.1% formic acid and methanol containing 0.1% formic acid as the mobile phase. The analytical performance of our method in terms of sensitivity, linearity, specificity, carryover, precision, limit of quantification, matrix effect, accuracy, dilution integrity, extraction recovery, stability, and crosstalk of all the analytes under different conditions met all the criteria stipulated by the guidelines of the Chinese Pharmacopoeia and U.S. Food and Drug Administration. The response function was estimated at 10.0-10 000.0 ng/mL for sorafenib, donafenib, apatinib, cabozantinib, regorafenib, and lenvatinib, and 20.0-20 000.0 ng/mL for 5-fluorouracil, oxaliplatin, capecitabin, morphine, fentanyl, and oxycodone, with a correlation of > 0.9956 for all compounds. The precision and accuracy of all analytes were < 7.21% and 5.62%, respectively. Our study provides empirical support for a simple, reliable, specific, and suitable technique for clinical TDM and pharmacokinetics.

Management of cancer treatments in hemodialysis patients

INTRODUCTION

The number of cancer patients receiving long-term hemodialysis (HD) is increasing, and HD could jeopardize treatments' safety and efficacy. Therefore, managing anticancer drugs is critical in this frail population. In addition, evidence of HD safety or risk is regularly released both for cytotoxic chemotherapy (CT) or hormone therapy (HT) as well as new therapies with molecularly targeted therapies (MTT), immune checkpoint inhibitors (ICI), and a summary of current knowledge is needed.

METHODS

We aimed to synthesize available data on cancer treatments in HD patients using PubMed database, FDA labels, summary of product characteristics (SmPC), FDA and EMA approval documents, guidelines and finally case reports for which relevant pharmacokinetic (PK) data is available.

RESULTS

For CT, recently proposed guidelines were balanced by the publication of particular toxic reports following them. SmPC was helpful in some cases, but no data was found for most CTs. MTT, both oral and monoclonal antibodies, were rarely modified by HD. However, HD patients have particular frailty that could require dose adaptation despite no substantial PK modification. Similarly, exposure to ICIs is unlikely to be modified by HD since immunoglobulins are not dialyzable. For HT, PK characteristics and HD impact were more heterogeneous and were reviewed molecule by molecule.

CONCLUSIONS

We summarized current knowledge on HD and cancer treatments. Data remains scarce, and the latest guidelines rely on few clinical data. There is a need to collect both retrospective and prospective data to better characterize the safety and relevant dose and schedule adaptations whenever needed in this situation to reinforce future guidelines.

LC-MS/MS Application in Pharmacotoxicological Field: Current State and New Applications

Nowadays, it is vital to have new, complete, and rapid methods to screen and follow pharmacotoxicological and forensic cases. In this context, an important role is undoubtedly played by liquid chromatography-tandem mass spectrometry (LC-MS/MS) thanks to its advanced features. This instrument configuration can offer comprehensive and complete analysis and is a very potent analytical tool in the hands of analysts for the correct identification and quantification of analytes. The present review paper discusses the applications of LC-MS/MS in pharmacotoxicological cases because it is impossible to ignore the importance of this powerful instrument for the rapid development of pharmacological and forensic advanced research in recent years. On one hand, pharmacology is fundamental for drug monitoring and helping people to find the so-called "personal therapy" or "personalized therapy". On the other hand, toxicological and forensic LC-MS/MS represents the most critical instrument configuration applied to the screening and research of drugs and illicit drugs, giving critical support to law enforcement. Often the two areas are stackable, and for this reason, many methods include analytes attributable to both fields of application. In this manuscript, drugs and illicit drugs were divided in separate sections, with particular attention paid in the first section to therapeutic drug monitoring (TDM) and clinical approaches with a focus on central nervous system (CNS). The second section is focused on the methods developed in recent years for the determination of illicit drugs, often in combination with CNS drugs. All references considered herein cover the last 3 years, except for some specific and peculiar applications for which some more dated but still recent articles have been considered.

SPK1/S1P axis confers gastrointestinal stromal tumors (GISTs) resistance of imatinib

BACKGROUND

Imatinib mesylate (IM) is highly effective in the treatment of gastrointestinal stromal tumors (GISTs). However, the most of GISTs patients develop secondary drug resistance after 1-3 years of IM treatment. The aim of this study was to explore the IM-resistance mechanism via the multi-scope combined with plasma concentration of IM, genetic polymorphisms and plasma sensitive metabolites.

METHODS

This study included a total of 40 GISTs patients who had been regularly treated and not treated with IM. The plasma samples were divided into three experiments, containing therapeutic drug monitoring (TDM), OCT1 genetic polymorphisms and non-targeted metabolomics. According to the data of above three experiments, the IM-resistant cell line, GIST-T1/IMR cells, was constructed for verification the IM-resistance mechanism.

RESULTS

The results of non-targeted metabolomics analysis suggested that the sphingophospholipid metabolic pathway including the SPK1/S1P axis was inferred in IM-insensitive patients with GISTs. A GIST cell line (GIST-T1) was immediately induced as an IM resistance cell model (GIST-T1/IMR) and we found that blocking the signal pathway of SPK1/S1P in the GIST-T1/IMR could sensitize treatment of IM and reverse the IM-resistance.

CONCLUSIONS

Our findings suggest that IM secondary resistance is associated with the elevation of S1P, and blockage the signaling pathway of SPK1/S1P warrants evaluation as a potential therapeutic strategy in IM-resistant GISTs. The design of this study from blood management, group information collection, IM plasma concentration with different elements, identification of sphingolipid metabolism and lastly verification the function of SPK1/S1P in the IM-resistance GISTs cells.

Development of a SPE-LC-MS Method for the Quantitation of Palbociclib and Abemaciclib in Human Plasma

Palbociclib and abemaciclib are two cyclin-dependent kinases 4 and 6 used for breast cancer treatment. Levels of these medicines present a significant interindividual variability, so monitoring those concentrations might be necessary in therapy. Most of the methods presented so far in the literature use simple protein precipitation of plasma proteins as sample preparation method followed by direct injection of the supernatant into the LC instrument, preceded or not by a simple filtration step. Within that approach, the probability of injecting proteins in the chromatographic system is increased. With the purpose of obtaining a cleaner extract of the drugs, we developed and validated a simple and accurate LC-MS method for determining palbociclib and abemaciclib in human plasma. Solid phase extraction (SPE) using Oasis PRiME HLB^® cartridges was used for plasma sample preparation. The method provided clean extracts with a recovery extraction higher than 85% for both compounds. Separation was achieved by high-performance liquid chromatography (HPLC), using a C18 (4.6 × 50 mm) column, with a gradient elution of ammonium acetate/acetic acid-acetonitrile as the mobile phase. Detection was performed by mass spectrometry (MS) in single ion recording (SIR) mode. Intra-day and inter-day precision data for both analytes were 3.8-7.2% and 3.6-7.4%, respectively. Calibration curves were both linear between 2 and 400 ng/mL with a correlation coefficient higher than 0.998. The LC-MS method can be used to quantify the drugs in human plasma in routine analysis. The method proved to be useful in determining real plasma levels in patients involved in cancer therapy. Drug concentrations were determined in a 10 min run-time, including re-equilibration of the column.

Development and application of an LC-MS/MS method for pharmacokinetic study of ruxolitinib in children with hemophagocytic lymphohistiocytosis

Ruxolitinib (RUX), a small molecule inhibitor of JAK1/JAK2, has been identified as the possible novel targeted agent for the treatment of hemophagocytic lymphohistiocytosis (HLH). However, due to the lack of randomized clinical trials (RCTs), it is extremely difficult to determine the effective therapeutic dose for RUX in HLH patients, especially in pediatric patients. At the same time, the clinical response of pediatric patients to RUX varies greatly among individuals according to several case reports. Therefore, it is imperative to investigate the pharmacokinetic and pharmacodynamic characteristics of RUX in HLH children, and this must be based on a satisfactory method to determine the concentration of RUX. Owing to several limits of published analytical methods, herein, we describe a novel liquid chromatography tandem mass spectrometry (LC-MS/MS) method for monitoring RUX in children's plasma samples. The protein precipitation method using methanol was used for sample cleanup. The analytes were separated by gradient elution in which 2.0 mM ammonium acetate in distilled water and acetonitrile were used as mobile phases. In the positive electrospray ionization (ESI+) mode, the m/z 307.1 → 186.0 and 316.1 → 185.9 ion pair transitions of RUX and RUX-d9 were used for the qualitative and quantitative analysis, respectively. The calibration curves of RUX were linear in the concentration range from 0.5 to 400 ng mL^-1. The intra- and inter-batch precision, accuracy, recovery, dilution completeness, and stability of this method were all within acceptable standards, and no matrix effects or residues were found. This method was successfully applied to the clinical pharmacokinetic study of RUX in 32 children with HLH. The pharmacokinetic parameters of HLH children after a single dose of RUX and the steady state plasma concentration after multiple administrations were proposed through this method. Most importantly, it was found that the age and serum creatinine (SCr) of children with HLH had a significant and complex impact on the in vivo process of RUX after the single as well as multiple administrations of RUX.

Therapeutic Drug Monitoring and Individualized Medicine of Dasatinib: Focus on Clinical Pharmacokinetics and Pharmacodynamics

Dasatinib is an oral second-generation tyrosine kinase inhibitor known to be used widely in Philadelphia chromosome-positive (Ph+) chronic myeloid leukemia (CML) and Ph+ acute lymphoblastic leukemia (ALL). Notably, although a high pharmacokinetic variability in patients and an increased risk of pleural effusion are attendant, fixed dosing remains standard practice. Retrospective studies have suggested that dasatinib exposure may be associated with treatment response (efficacy/safety). Therapeutic drug monitoring (TDM) is gradually becoming a practical tool to achieve the goal of individualized medicine for patients receiving targeted drugs. With the help of TDM, these patients who maintain response while have minimum adverse events may achieve long-term survival. This review summaries current knowledge of the clinical pharmacokinetics variation, exposure-response relationships and analytical method for individualized dosing of dasatinib, in particular with respect to therapeutic drug monitoring. In addition, it highlights the emerging insights into several controversial issues in TDM of dasatinib, with the aim of presenting up-to-date evidence for clinical decision-making and insights for future studies.

A Novel LC-MS Method for the Determination of Abiraterone in Rat Plasma and its Application to Pharmacokinetic Studies

Background:

High-Performance Liquid Chromatography (HPLC)-Ultraviolet (UV) and Liquid Chromatography (LC)-Mass Spectrometry (MS)/MS methods have been used to analyse abiraterone (ART); however, a single-quadrupole mass spectrometer with LC-MS systems has never been used to analyse ART.

Objective:

The study aimed to establish a novel, simple assay of quantitating ART in rat plasma through LC-MS.

Method:

The analytical procedure involved the extraction of ART and D4-ART (internal standard, IS) from rat plasma through simple protein precipitation. Chromatographic separation was achieved using an isocratic mobile phase (acetonitrile: 5 mM ammonium formate with 0.1% formic acid, 50:50 v/v) at a flow rate of 0.30 mL/min on a Waters XBridge® C18 column with a total run time of 5 min. LC-MS ion transitions monitored were 350.1 and 354.1 for ART and IS, respectively. The method was validated, and the results met acceptance criteria.

Results:

The lower limit of quantitation achieved was 1 ng/mL, and linearity was 1-8000 ng/mL. The intra- and inter-day precisions were 1.26%-14.20% and 5.49%-13.08%, respectively, in rat plasma.

Conclusion:

LC-MS offers a novel, specific, sensitive, and accurate method for quantifying ART and it was successfully applied to pharmacokinetic studies of ART in rats.