Validation of an LC-MS/MS method for simultaneous determination of icotinib and its four major circulating metabolites in human plasma and its application in a pharmacokinetic study.

In this study, a simple and sensitive LC-MS/MS method was developed and validated for simultaneous determination of icotinib and its four circulating metabolites in human plasma. The analytes were extracted with acetonitrile and separated on a C18 column using 2 mm ammonium acetate containing 0.2% formic acid and acetonitrile as mobile phase. The analytes were introduced into the mass spectrometer via an electrospray ionization source operated in positive ion mode. Precursor-to-product transitions were optimized to be m/z 392.2 → 304.1 for icotinib, m/z 424.1 → 278.2 for M1 and M2, m/z 408.2 → 320.1 for M3, m/z 410.2 → 322.1 for M4 and m/z 394.4 → 278.1 for IS. The assay showed good linearity over the concentration ranges of 0.1-600 ng/mL for icotinib and 0.1-200 ng/mL for metabolites, with correlation coefficients >0.994 (r > 0.994). The LLOQ was 0.1 ng/mL for each analyte. The intra- and inter-day precisions (RSD) were ≤12.98% while the accuracy (RE) ranged from -8.76 to 12.01%. No significant matrix effect was observed. The validated method was successfully applied for the pharmacokinetic study of icotinib and its four circulating metabolites in human plasma after oral administration of icotinib at a single dose of 125 mg.

Impact of whole brain radiation therapy on CSF penetration ability of Icotinib in EGFR-mutated non-small cell lung cancer patients with brain metastases: Results of phase I dose-escalation study.

OBJECTIVES: Whole-brain radiation therapy (WBRT) and epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) are both treatment options for EGFR-mutated non-small cell lung cancer (NSCLC) patients with brain metastases. However, the dose-escalation toxicity and efficacy of combination therapy, and the effect of WBRT on cerebrospinal fluid (CSF) penetration of EGFR-TKIs are still unclear. MATERIALS AND METHODS: EGFR-mutated NSCLC patients with brain metastases were enrolled in this study, and the cohorts were constructed with a 3+3 design. The patients received icotinib with escalating doses (125-625mg, tid), and the concurrent WBRT (37.5Gy/15f/3weeks) started a week later. The CSF penetration rates of icotinib were tested before, immediately after, and 4 weeks after WBRT, respectively. Potential toxicities and benefits from dose-escalation treatment were analyzed. RESULTS: Fifteen patients were included in this study, 3 at each dose level from 125mg-375mg and 6 at 500mg with 3 occurred dose-limiting toxicities. The maximal tolerated dose of icotinib was 375mg tid in this combination therapy. There was a significant correlation between icotinib concentration in the CSF and plasma (R(2)=0.599, P<0.001). The CSF penetration rate of icotinib, from 1.2% to 9.7%, reached a maximum at 375mg (median, 6.1%). There was no significant difference for CSF penetration rates among the three test points (median, 4.1% vs. 2.8% vs. 2.8%, P=0.16). The intracranial objective response rate and median intracranial progression free survival are 80% and 18.9 months. CONCLUSIONS: WBRT plus concurrent icotinib is well tolerated in EGFR-mutated NSCLC patients with brain metastases, up to an icotinib dose of 375mg tid. The icotinib CSF concentration seemed to have a potential ceiling effect with the dose escalation, and WBRT seemed to have no significant impact on CSF penetration of icotinib till 4 weeks after the treatment.

A phase II study of icotinib and whole-brain radiotherapy in Chinese patients with brain metastases from non-small cell lung cancer.

PURPOSE: Icotinib is a new first-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors. A phase II study was conducted to evaluate the efficacy and safety of icotinib in combination with whole-brain radiotherapy (WBRT) in Chinese NSCLC patients with brain metastases (BMs); the cerebrospinal fluid (CSF)/plasma concentrations of icotinib were also investigated. METHODS: Eligible patients had BMs from NSCLC, regardless of the EGFR status. Icotinib was administered at 125 mg orally 3 times/day until tumor progression or unacceptable toxicity, concurrently with WBRT (3.0 Gy per day, 5 days per week, to 30 Gy). CSF and plasma samples were collected simultaneously from 10 patients. Icotinib concentrations in the CSF and plasma were measured by high-performance liquid chromatography coupled with tandem mass spectrometry. RESULTS: Twenty patients were enrolled. The median follow-up time was 20.0 months. The overall response rate was 80.0%. The median progression-free survival time was 7.0 months (95% CI 1.2-13.2 months), and the median survival time (MST) was 14.6 months (95% CI 12.5-16.7 months). Of the 18 patients with known EGFR status, the MST was 22.0 months for those with an EGFR mutation and was 7.5 months for those with wild-type EGFR (P = 0.0001). The CSF concentration and penetration rate of icotinib were 11.6 ± 9.1 ng/mL and 1.4 ± 1.1%, respectively. No patient experienced ≥grade 4 toxicity. CONCLUSIONS: Icotinib was well tolerated in combination with WBRT and showed efficacy in patients with BMs from NSCLC. This clinical benefit was related to the presence of activating EGFR mutations.

Development of population pharmacokinetics model of icotinib with non-linear absorption characters in healthy Chinese volunteers to assess the CYP2C19 polymorphism and food-intake effect.

PURPOSE: Icotinib is a potent and selective inhibitor of epidermal growth factor receptors (EGFR) approved to treat non-small cell lung cancer (NSCLC). However, its high variability may impede its application. The objectives of this analysis were to assess plasma pharmacokinetics and identify covariates that may explain variability in icotinib absorption and/or disposition following single dose of icotinib in healthy volunteers. METHODS: Data from two clinical studies (n = 22) were analyzed. One study was designed as three-period and Latin-squared (six sequence) trial to evaluate dose proportionality, and the other one was designed as two-way crossover trial to evaluate food effect on pharmacokinetics (PK) characters. Icotinib concentrations in plasma were analyzed using non-linear mixed-effects model (NONMEM) method. The model was used to assess influence of food, demographic characteristics, measurements of blood biochemistry, and CYP2C19 genotype on PK characters of icotinib in humans. The final model was diagnosed by goodness-of-fit plots and evaluated by visual predictive check (VPC) and bootstrap methods. RESULTS: A two-compartment model with saturated absorption character was developed to capture icotinib pharmacokinetics. Typical value of clearance, distribution clearance, central volume of distribution, maximum absorption rate were 29.5 L/h, 24.9 L/h, 18.5 L, 122.2 L and 204,245 µg/h, respectively. When icotinib was administrated with food, bioavailability was estimated to be increased by 48%. Inter-occasion variability was identified to affect on maximum absorption rate constant in food-effect study. CL was identified to be significantly influenced by age, albumin concentration (ALB), and CYP2C19 genotype. No obvious bias was found by VPC and bootstrap methods. CONCLUSIONS: The developed model can capture icotinib pharmacokinetics well in healthy volunteers. Food intake can increase icotinib exposure. Three covariates, age, albumin concentration, and CYP2C19 genotype, were identified to significantly affect icotinib PK profiles in healthy subjects.

Clinical pharmacokinetics of Icotinib, an anti-cancer drug: evaluation of dose proportionality, food effect, and tolerability in healthy subjects.

PURPOSE: Icotinib, an oral epidermal growth factor receptor tyrosine kinase inhibitor, has proved effectiveness in xenografted nude mice. Purpose of the present studies was to investigate tolerability and pharmacokinetics of Icotinib in healthy subjects for the first time, including dose proportionality, food effect, and tolerability. METHODS: Two studies were conducted in total of 22 healthy subjects: a randomized, two-Latin-square crossover, dose proportional study (n = 12) and a randomized two-way crossover food-effect study (n = 10). RESULTS: Plasma concentration of Icotinib reached peak at a median Tmax of 0.75-3.5 h after single dose and then declined with a mean t1/2ß of 6.02-7.83 h. Over the dose range of 100-600 mg, AUC values were proportional to dose and Cmax showed a slight saturation when dose increases. Only 0.2 % of the dose was excreted through kidney in unchanged Icotinib. After dosing 400 mg of Icotinib with high-fat and high-calorie meal, mean Cmax and AUC were significantly increased by 59 and 79 %, respectively. Three subjects experienced four adverse events (rash, increase in AST and ALT, and external injury). Rash and increased levels of AST and ALT were considered as drug-related. No serious adverse events were reported. CONCLUSION: The current work demonstrated that Icotinib was well tolerated in healthy male subjects (n = 22) over the dose range of 100-600 mg with or without food. Icotinib exposure, expressed in AUC, was proportionally increased with dose over the above dose range. Food intake significantly increased the absorption and exposure of Icotinib in healthy subjects.

Effect of the CYP2C19 genotype on the pharmacokinetics of icotinib in healthy male volunteers.

PURPOSE: Icotinib hydrochloride {4-[(3-ethynylphenyl)amino]-6,7-benzo-12-crown-4-quinazoline hydrochloride}, a novel epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI), was designed for the treatment of non-small cell lung cancer (NSCLC). In the present study, we investigated the influence of the CYP2C19*2 and CYP2C19*3 alleles on the pharmacokinetics of icotinib in healthy Chinese volunteers. METHODS: In a single-dose pharmacokinetic study, 12 healthy Chinese volunteers received an oral dose of 600 mg of icotinib. Plasma was sampled for up to 72 h post-dose, followed by quantification of icotinib by liquid chromatography-mass spectrometry/mass spectrometry (LC-MS-MS). RESULTS: Five subjects genotyped as homozygous extensive metabolizers (CYP2C19*1/*1), 6 subjects genotyped as heterozygous extensive metabolizers (CYP2C19*1/*2 or CYP2C19*1/*3), and 1 subject genotyped as a poor metabolizer (CYP2C19*2/*3) and was withdrawn from the research because of urticaria. The mean icotinib AUC(0-∞) and C(max) (14.56 ±5.31 h mg/L and 2.32 ± 0.49 µg/mL) in homozygous EMs was 1.56 and 1.41-fold lower than that in heterozygous EMs (22.7 ± 6.11 and 3.28 ± 0.48, P = 0.046 and 0.047). The mean CL/F (44.18 ± 12.17 L/h) in homozygous EMs was 1.55-fold higher than that in heterozygous EMs (28.42 ± 9.23 L/h, P = 0.013). CONCLUSIONS: The data showed that the pharmacokinetics of icotinib differ significantly between homozygous EMs and heterozygous EMs in CYP2C19.

Metabolite characterization of a novel anti-cancer agent, icotinib, in humans through liquid chromatography/quadrupole time-of-flight tandem mass spectrometry.

Icotinib is a novel anti-cancer drug that has shown promising clinical efficacy and safety in patients with non-small-cell lung cancer (NSCLC). At this time, the metabolic fate of icotinib in humans is unknown. In the present study, a liquid chromatography/quadrupole time-of-flight tandem mass spectrometry (LC/Q-TOF MS) method was established to characterize metabolites of icotinib in human plasma, urine and feces. In addition, nuclear magnetic resonance (NMR) detection was utilized to determine the connection between side-chain and quinazoline groups for some complex metabolites. In total, 29 human metabolites (21 isomer metabolites) were characterized, of which 23 metabolites are novel compared to the metabolites in rats. This metabolic study revealed that icotinib was extensively metabolized at the 12-crown-4 ether moiety (ring-opening and further oxidation), carbon 15 (hydroxylation) and an acetylene moiety (oxidation) to yield 19 oxidized metabolites and to further form 10 conjugates with sulfate acid or glucuronic acid. To our knowledge, this is the first report of the human metabolic profile of icotinib. Study results indicated that significant attention should be paid to the metabolic profiles of NSCLC patients during the development of icotinib.

Phase I study of icotinib hydrochloride (BPI-2009H), an oral EGFR tyrosine kinase inhibitor, in patients with advanced NSCLC and other solid tumors.

PURPOSE: The goal of this study was to assess the safety and tolerability of icotinib hydrochloride (BPI-2009H), a new selective epidermal growth factor receptor tyrosine kinase inhibitor (EGFR TKI), and to explore its pharmacokinetics (PK) and clinical activity in patients with advanced solid tumors, mainly those with non-small-cell lung cancer (NSCLC) after the failure of the prior platinum-based chemotherapy. EXPERIMENTAL DESIGN: Different doses of oral icotinib were administered once every 8 h (Q8H) for a 28-continuous-day cycle until disease progression and or undue toxicity was observed. PK studies of subjects' blood were performed during cycle one (day 1 through 28). Patients aged ≥18 and ≤70 years with an Eastern Cooperative Oncology Group (ECOG) performance status (PS) of 0-1 and adequate organ functions eligible for the study. Tumor responses were assessed by Response Evaluation Criteria in Solid Tumors (RECIST). K-ras and EGFR mutations in the extracted DNA of fourteen specimens were examined using PCR-based direct sequencing assay. RESULTS: Thirty-six patients were enrolled in the study. PK analysis demonstrated that the mean elimination half-life of icotinib was 6 h, and the T(max) was around 2 h. The steady-state concentration of icotinib administered at a dose of 125 mg once every 8 h (Q8H) was significantly higher than that achieved by a dose of 100mg Q8H. The most frequent treatment-related adverse events (TRAEs) were an acne-like (folliculitis) rash (16/36, 44.4%), diarrhea (8/36, 22.2%) and a decrease in white blood cells (4/36, 11.1%). The maximum-tolerated dose (MTD) was not reached. Among 33 patients with NSCLC, 7 patients exhibited a partial response, 7 showed stable disease at the 24 weeks. Among 14 patients undergoing DNA sequence for K-ras and EGFR mutations, 3 with K-ras mutation presented 2 stable disease (SD) and 1 partial response (PR), 5 with EGFR exon 19 or 21 mutation 2 PR and 3 SD within 4 weeks. CONCLUSIONS: Oral icotinib was generally well tolerated, with manageable and reversible adverse events (AEs) and showed positive clinical anti-tumor activities in patients with advanced NSCLC. The recommended dose for phase II/III studies with icotinib is 125 mg or 150 mg Q8H.

Quantitative determination of icotinib in human plasma and urine using liquid chromatography coupled to tandem mass spectrometry.

We developed a rapid, specific and sensitive method based on high performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS) to determine icotinib concentrations in human plasma and urine. Liquid-liquid extraction (LLE) and direct dilution were firstly used to isolate icotinib from plasma and urine followed by injection of the extracts onto a C(18) column with gradient elution. Ionization of icotinib and midazolam (internal standard, IS) was performed using an electrospray ionization source in positive mode and detection was carried out in multi-reaction monitoring (MRM) mode. The lower limits of quantitation (LLoQ) of icotinib in human plasma and urine by this method were 0.1 and 1.00ng/mL, respectively. The accuracy, precision, specificity, recovery, matrix effect, linearity and several of stabilities have been validated for icotinib in human plasma and urine. In conclusion, the validation results showed that this method is robust, specific and sensitive and it can successfully fulfill the requirement of clinical pharmacokinetic study of icotinib hydrochloride in Chinese healthy subjects.