A fully validated method for simultaneous determination of icotinib, osimertinib, gefitinib and O-desmethyl gefitinib in human plasma using UPLC-MS/MS for therapeutic drug monitoring

BACKGROUND AND AIMS

A few researches have reported the exposure-efficacy/toxicity relationships of epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs). On account of the large interpatient pharmacokinetic variability, therapeutic drug monitoring (TDM) seems promising for optimizing dosage regimen and improving treatment efficacy and safety. Therefore, a rapid and convenient ultrahigh performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed and validated for the determination of icotinib, osimertinib, gefitinib and O-demesthyl gefitinib in human plasma for TDM.

MATERIALS AND METHODS

Icotinib-D4 and osimertinib-13CD3 were used as the internal standards (ISs). The samples were prepared by protein precipitation using acetonitrile. Chromatographic separation was achieved on a 40 ℃ Shimadzu Shim-pack Scepter C18-120 column (2.1 ×50 mm, 3.0 µm, Japan) by a Shimadzu 30 A solvent management system. Detection was carried out using a Shimadzu LC-MS 8050CL triple quadrupole mass spectrometer coupled with an electrospray ionization source in positive mode.

RESULTS

This analytical method was fully validated with selectivity, carry-over, linearity, lower limit of quantification, accuracy (from 92.68% to 106.62%) and precision (intra- and inter-day coefficients of variation ranged from 0.92% to 9.85%), matrix effect, extraction recovery, stability and dilution integrity. The calibration curves were developed to be within the concentration ranges of 200-4000 ng/mL for icotinib, 50-1000 ng/mL for osimertinib, gefitinib and O-desmethyl gefitinib in human plasma which meet the needs of routine TDM.

CONCLUSIONS

The proposed method was used in 100 patients with non-small cell lung cancer for monitoring plasma concentration of the mentioned EGFR-TKIs. The trough concentrations of ICO were distributed between 226.42 ng/mL and 3853.36 ng/mL, peak concentrations were between 609.20 ng/mL and 2191.54 ng/mL. The trough concentrations of OSI were distributed between 110.48 ng/mL and 1183.13 ng/mL. The trough concentrations of GEF were distributed between 117.71 ng/mL and 582.74 ng/mL, while DeGEF was distributed from 76.21 ng/mL to 1939.83 ng/mL with two less than 20 ng/mL. The results of therapeutic drug monitoring aimed to investigate exposure-efficacy/toxicity relationship and improve the efficacy and safety of targeted therapies.

Rapid extraction of osimertinib and its active metabolite in urine by miniaturized centrifugal spin-column extraction using ionic liquid hybrid hierarchical porous adsorbent

Osimertinib (OSIM) is widely used as a mainstream drug for the treatment of non-small cell lung cancer (NSCLC). However, the lack of a rapid extraction and detection method for OSIM and its metabolite, AZ-5104, has limited clinical drug metabolism and drug resistance research because the drug is unstable. In this study, a new ionic liquid hybrid hierarchical porous material (IL-HHPM) was synthesized with hierarchical porous structures, including micropores (1.6-2.0 nm), mesopores (2.0-50.0 nm), macropores (50.0-148.7 nm), and multiple functional groups via a one-step hydrothermal method using silanized ionic liquids (IL) as functionalized hybrid monomer. The IL-HHPM has the advantages of a high specific surface area (437.4 ± 4.6 m2 g-1), sizable pore volume (0.74 cm3 g-1), and fast mass transfer, additionally, the IL-HHPM adsorbed OSIM and AZ-5104 via π-π interactions and hydrogen bonding. OSIM and AZ-5104 were rapidly extracted and measured in human urine using rapid and miniaturized centrifugal spin-column extraction (MCSCE), which was based on the IL-HHPM. The optimized factors for the extraction recoveries of OSIM and AZ-5104 were adsorbent dosage (8.0 mg), sample volume (0.5 mL), and operation time (9.0 min), and markedly reduced the adsorbent dosage and operation time. The IL-HHPM-MCSCE-HPLC method displayed good linearity (0.02-5.00 μg mL-1, r ≥ 0.9997), satisfying accuracy (spiked recoveries of 87.7%-100.0%), and good precision (RSDs ≤ 7.0%). The developed method is rapid, sensitive, and reproducible for the simultaneous determination of trace level of OSIM and AZ-5104 in human urine.

Determining plasma and cerebrospinal fluid concentrations of EGFR-TKI in lung cancer patients

Epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) are commonly used to treat advanced non-small cell lung cancer (NSCLC). A rapid and reliable method for measuring plasma and cerebrospinal fluid (CSF) concentrations of EGFR-TKIs is needed for therapeutic drug monitoring. By using UHPLC‒MS/MS with multiple reaction monitoring mode, we developed a method for rapidly determining the plasma and CSF concentrations of gefitinib, erlotinib, afatinib, and osimertinib. Protein precipitation was employed to remove protein interference for plasma and CSF matrix. The LC‒MS/MS assay was validated to be satisfactory in terms of linearity, precision, and accuracy. This method was successfully applied to measure plasma (n = 44) and CSF (n = 6) concentrations of EGFR-TKIs in NSCLC patients. The chromatographic separation was achieved by a Hypersil Gold aQ column within 3 minutes. The median plasma concentrations were 325.76, 1981.50, 42.62, 40.27, and 340.92 ng/ml for gefitinib erlotinib, afatinib 30 mg/day, afatinib 40 mg/day, and osimertinib, respectively. The CSF penetration rates were 2.15% for the patients receiving erlotinib therapy, 0.59% for afatinib, 0.08-1.12% for osimertinib 80 mg/day, and 2.18% for those receiving osimertinib 160 mg/day. This assay helps to predict the effectiveness and toxicities of EGFR-TKIs in the pursuit of precision medicine for lung cancer patients.

Development and validation of an LC-MS/MS method for simultaneous determination of SH-1028, an irreversible third-generation EGFR TKI, and two of its metabolites in human plasma: application in clinical pharmacokinetics

SH-1028 is a novel, potent, and highly selective epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) developed for the treatment of T790M Mutation-positive non-small cell lung cancer (NSCLC). The objective was to develop an LC-MS/MS method for the simultaneous determination of SH-1028 and its metabolites, Imp2 and Imp3, in human plasma.The plasma samples were extracted through protein precipitation with acetonitrile on wet ice conditions. A rapid, sensitive, and specific method was developed and successfully applied to evaluate the pharmacokinetic (PK) properties of SH-1028 in patients with advanced NSCLC following single and multiple doses of SH-1028 (60 mg).After single-dose administration, the C_max of SH-1028, Imp2, and Imp3 was 11.2, 50.2, and 7.99 ng/mL, respectively. The mean AUC_0-24 h was 138, 602, and 76.7 h*ng/mL, respectively. And the terminal half-life time was 19.9, 14.4, and 26.1 h, respectively. After multiple-dose administration, SH-1028 exhibited a slight accumulation, with a mean accumulation ratio (R_AUC) of 2.00.The study assessed the PK properties of SH-1028 following single and multiple doses in patients with advanced NSCLC and would provide meaningful information for the further development of SH-1028.

Instability Mechanism of Osimertinib in Plasma and a Solving Strategy in the Pharmacokinetics Study

Osimertinib is a third-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) and a star medication used to treat non-small-cell lung carcinomas (NSCLCs). It has caused broad public concern that osimertinib has relatively low stability in plasma. We explored why osimertinib and its primary metabolites AZ-5104 and AZ-7550 are unstable in rat plasma. Our results suggested that it is the main reason inducing their unstable phenomenon that the Michael addition reaction was putatively produced between the Michael acceptor of osimertinib and the cysteine in the plasma matrix. Consequently, we identified a method to stabilize osimertinib and its metabolite contents in plasma. The assay was observed to enhance the stability of osimertinib, AZ-5104, and AZ-7550 significantly. The validated method was subsequently applied to perform the pharmacokinetic study for osimertinib in rats with the newly established, elegant, and optimized ultra-performance liquid chromatography–tandem mass spectrometer (UPLC-MS/MS) strategy. The assay was assessed for accuracy, precision, matrix effects, recovery, and stability. This study can help understand the pharmacological effects of osimertinib and promote a solution for the similar problem of other Michael acceptor-contained third-generation EGFR-TKI.

A Phase I Trial of Dasatinib and Osimertinib in TKI Naïve Patients With Advanced EGFR-Mutant Non-Small-Cell Lung Cancer

Background

Osimertinib is an effective first-line therapy option for EGFR-mutant NSCLC, but virtually all patients develop resistance. CRIPTO, through Src activation, has been implicated in resistance to EGFR tyrosine kinase inhibitor (EGFR-TKI) therapy. Dasatinib, a Src inhibitor, has shown preclinical synergy with EGFR-TKI therapy.

Method

This is a single-arm phase I/II trial of osimertinib and dasatinib in TKI-naïve advanced EGFR-mutant NSCLC (NCT02954523). A 3 + 3 design was used in the phase I to establish the recommended phase II dose (RP2D). Osimertinib 80 mg QD was combined with dasatinib 70 mg BID (DL2), 50 mg BID (DL1), 70 mg QD (DL-1), and 50 mg QD (DL-2).

Results

Ten patients (DL2: 3, DL1: 6, DL -1: 1) were enrolled. 3 (50%) of 6 patients at DL1 experienced a DLT (grade 3 headaches/body pain, neutropenia, rash, one each). Common treatment-related adverse events included pleural effusion (n=10), diarrhea (n=8), rash (n=7), transaminitis (n=7), thrombocytopenia (n=7), and neutropenia (n=7). While the MTD was not determined by protocol-defined DLT criteria, DL-2 was chosen as the RP2D, considering overall tolerability. Nine (90%) patients had a PR, including 1 unconfirmed PR. Median PFS was 19.4 months and median OS 36.1 months. The trial was closed to accrual prematurely due to slow accrual after the approval of osimertinib as first-line therapy.

Conclusions

The combination of dasatinib and osimertinib demonstrated anticancer activity. The treatment was limited by chronic toxicities mainly attributed to dasatinib. To improve the safety and tolerability of Src and EGFR co-inhibition, Src inhibitors with a more favorable safety profile should be utilized in future studies.

Clinical Trial Registration

https://clinicaltrials.gov/ct2/show/NCT02954523.

Chromatographic bioanalytical assays for targeted covalent kinase inhibitors and their metabolites

Deriving from targeted kinase inhibitors (TKIs), targeted covalent kinase inhibitors (TCKIs) are a new class of TKIs that are covalently bound to their target residue of kinase receptors. Currently, there are many new TCKIs under clinical development besides afatinib, ibrutinib, osimertinib, neratinib, acalabrutinib, dacomitinib, and zanubrutinib that are already approved by the FDA. Subsequently, there is an increasing demand for bioanalytical methods to qualitatively and quantitively investigate those compounds, leading to a number of papers reporting the development, validation, and use of bioanalytical methods for TCKIs. Most publications describe the technological set up of analytical methods that allow quantification of TCKIs in various biomatrices such as plasma, cerebrospinal fluid, urine, tissue, and liver microsomes. In addition, the identification of metabolites and biotransformation pathways of new TCKIs has gained more interest in recent years. We provide an overview of bioanalytical methods of this new class of TCKIs. The included issues are sample pretreatment, chromatographic separation, detection, and method validation. In the scope of bioanalysis of TCKIs, protein precipitation is mostly applied to treat the biological matrices sample. Liquid chromatographic in reversed-phase mode (RPLC) and mass detection with triple quadrupole (QqQ) are the most often utilized separation and quantitative detection modes, respectively. There may be a possibility of increased use of the high-resolution mass spectrometry (HRMS) for qualitative investigation purposes in the future. We also found that US FDA and EMA guidelines are the most common guidelines employed as validation framework for the bioanalytical methods of TCKIs.

Rapid and Sensitive Quantification of Osimertinib in Human Plasma Using a Fully Validated MALDI-IM-MS/MS Assay

The third-generation tyrosine kinase inhibitor (TKI), osimertinib, has revolutionized the treatment of patients with non-small cell lung carcinoma with epidermal growth factor receptor (EGFR)-activating mutation, and resistant to first- and second-generation TKIs. Osimertinib is now also proposed as a first-line therapy, thus extending the scope of applications in lung oncology. Personalized medicine approaches are still necessary to monitor if patients are exposed to adequate concentrations of osimertinib during their treatment. It would also help to understand the appearance of new resistances in patients after several months of dosing with osimertinib. Liquid chromatography–tandem mass spectrometry (LC–MS/MS) is currently the gold standard for the quantification of drugs in plasma enabling pharmacokinetic analyses and patient monitoring. In the present study, we propose an alternative to LC–MS/MS methods for the rapid and sensitive quantification of osimertinib in plasma using matrix-assisted laser desorption/ionization (MALDI) –MS. The presented assay requires only 3 min per sample for their preparation, analysis, and data extraction, and less than 3 h for quantification. A lower limit of quantification (LLOQ) of 5 ng/mL in plasma was retrieved. The method was fully validated, following the guidelines of the US Food and Drug Administration (FDA) and the European Medicines Agency (EMA) for bioanalytical method validation. The present developments prove the importance to consider alternative MS assays for time-efficient quantification of small molecule inhibitors in plasma in the context of personalized medicine for targeted therapies.