RESUMO
PURPOSE: Cetuximab inhibits epidermal growth factor receptor (EGFR) signaling in cancer and skin cells, thereby inducing anti-cancer effects and skin disorders. The present study aimed to evaluate the relationships between serum cetuximab and EGFR-related markers, and adverse effects in head and neck cancer patients. METHODS: Thirty-four head and neck cancer patients receiving weekly intravenous cetuximab were enrolled. Serum cetuximab levels were determined just before dosing. Blood samples for determination of serum EGFR-related markers including soluble epidermal growth factor receptor (sEGFR) and interleukin-6 (IL-6) were obtained. The severities of skin disorders, their medications, and hypomagnesemia treatment were also assessed. RESULTS: Serum levels of cetuximab and sEGFR were negatively and positively correlated with that of IL-6, respectively. The serum cetuximab level was twofold higher in the patients with a grade 2-3 skin rash than with a grade 0-1 rash. The serum cetuximab cutoff value related to severe skin rash was 71 µg/mL (sensitivity, 59%; and specificity, 94%). The use of a strong topical corticosteroid for skin rash was also associated with a higher serum cetuximab level. Serum levels of sEGFR and IL-6 had no correlations with the skin disorder severities or their medications. Hypomagnesemia treatment using intravenous magnesium sulfate was not related to serum cetuximab and EGFR-related markers. CONCLUSIONS: Head and neck cancer patients with a higher serum IL-6 level tended to have a lower serum cetuximab level. Serum cetuximab had positive correlations to skin rash severity and its medication in the study population.
Assuntos
Cetuximab/sangue , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Dermatopatias/induzido quimicamente , Idoso , Cetuximab/efeitos adversos , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/sangue , Feminino , Neoplasias de Cabeça e Pescoço/sangue , Humanos , Interleucina-6/sangue , Magnésio/sangue , Masculino , Pessoa de Meia-Idade , Estudos ProspectivosRESUMO
Radionuclide molecular imaging of cancer-specific targets is a promising method to identify patients for targeted antibody therapy. Radiolabeled full-length antibodies however suffer from slow clearance, resulting in high background radiation. To overcome this problem, a pretargeting system based on complementary peptide nucleic acid (PNA) probes has been investigated. The pretargeting relies on sequential injections of primary, PNA-tagged antibody and secondary, radiolabeled PNA probe, which are separated in time, to allow for clearance of non-bound primary agent. We now suggest to include a clearing agent (CA), designed for removal of primary tumor-targeting agent from the blood. The CA is based on the antibody cetuximab, which was conjugated to PNA and lactosaminated by reductive amination to improve hepatic clearance. The CA was evaluated in combination with PNA-labelled trastuzumab, T-ZHP1, for radionuclide HER2 pretargeting. Biodistribution studies in normal mice demonstrated that the CA cleared ca. 7 times more rapidly from blood than unmodified cetuximab. Injection of the CA 6 h post injection of the radiolabeled primary agent [131I]I-T-ZHP1 gave a moderate reduction of the radioactivity concentration in the blood after 1 h from 8.5 ± 1.8 to 6.0 ± 0.4%ID/g. These proof-of-principle results could guide future development of a more efficient CA.
Assuntos
Anticorpos Antineoplásicos/administração & dosagem , Anticorpos Antineoplásicos/química , Imunoconjugados/administração & dosagem , Imunoconjugados/química , Ácidos Nucleicos Peptídicos/administração & dosagem , Ácidos Nucleicos Peptídicos/química , Radioimunoterapia/métodos , Animais , Anticorpos Antineoplásicos/metabolismo , Linhagem Celular Tumoral , Cetuximab/administração & dosagem , Cetuximab/sangue , Cetuximab/química , Feminino , Humanos , Imunoconjugados/farmacocinética , Camundongos , Sondas Moleculares/administração & dosagem , Sondas Moleculares/química , Sondas Moleculares/farmacocinética , Terapia de Alvo Molecular/métodos , Ácidos Nucleicos Peptídicos/farmacocinética , Receptor ErbB-2/antagonistas & inibidores , Receptor ErbB-2/imunologia , Distribuição Tecidual , Trastuzumab/administração & dosagem , Trastuzumab/sangue , Trastuzumab/químicaRESUMO
PURPOSE: The aim of this work was to identify whether biochemical and physiological sources of mAb pharmacokinetic sex-effects could be identified in the rat model where target-mediated disposition is avoided. METHODS: Plasma and lymphatic pharmacokinetics of the humanised anti-EGFR antibody cetuximab, along with potential physiological and biochemical drivers of pharmacokinetic sex differences, were examined in male and female rats. Cetuximab was used as a model mAb since plasma clearance is slower in female patients. RESULTS: When plasma concentrations were normalised to dose, female rats displayed slower plasma clearance than males, but no significant differences were observed in liver and spleen biodistribution. Sex differences in apparent plasma clearance, however, were abolished after normalisation to body weight, surface area or fat-free mass. Significant sex differences were observed in plasma testosterone, endogenous IgG and fat free mass, but did not correlate with apparent clearance. Females did, however, show two-fold higher lymphatic exposure compared to males. CONCLUSIONS: These data suggested that mAbs more efficiently access lymph in females, but this does not affect plasma pharmacokinetics or biodistribution. Further, the data suggest that sex differences observed in humans could be a function of antigen density.
Assuntos
Antineoplásicos Imunológicos/farmacocinética , Cetuximab/farmacocinética , Sistema Linfático/metabolismo , Administração Intravenosa , Animais , Antineoplásicos Imunológicos/administração & dosagem , Antineoplásicos Imunológicos/sangue , Cetuximab/administração & dosagem , Cetuximab/sangue , Feminino , Masculino , Taxa de Depuração Metabólica , Ratos Sprague-Dawley , Fatores Sexuais , Distribuição TecidualRESUMO
BACKGROUND: Cetuximab (CTX) is a chimeric IgG1 Kappa monoclonal antibody used to treat head and neck cancer and colorectal cancer. Previous clinical studies indicated that the pharmacokinetics of CTX influences patient survival. Thus, individualizing CTX treatment by measuring trough levels of the drug in plasma could have a major impact on clinical efficacy. METHODS: To measure these levels, a full-length stable isotope-labeled CTX standard was used in a generic, rapid, and high-throughput sample preparation protocol based on IgG capture followed by trypsin digestion, on-line solid-phase extraction cleanup, and liquid chromatography-high resolution mass spectrometry (LC-HRMS). RESULTS: The optimized method displayed good analytical performance and was linear over a range from 5 to 150 mcg/mL. The within-run and between-run imprecision of the assay were equal to or less than 10%, for 6 replicates at 3 different concentrations and for runs performed on 5 separate days. The plasma CTX concentrations in 19 patients were also determined. CONCLUSIONS: The results showed that quantification of mAb in clinical samples does not strictly require a tandem mass spectrometry system, and LC-HRMS is also relevant in this context. This first study implementing a quantitative LC-HRMS assay with a specific stable isotope-labeled mAb internal standard paves the way for more robust clinical monitoring of anticancer mAbs.
Assuntos
Anticorpos Monoclonais/sangue , Isótopos de Carbono/sangue , Cetuximab/sangue , Isótopos de Nitrogênio/sangue , Plasma/química , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Marcação por Isótopo/métodos , Espectrometria de Massas em Tandem/métodosRESUMO
This study describes, for the first time, the development of an automated sensitive flow fluorescent noncompetitive immunoassay based on kinetic-exclusion analysis (KinExA) for the quantitative determination of human plasma levels of monoclonal antibodies (mAbs) used for cancer immunotherapy. The assay was adapted on KinExA™ 3200 biosensor and optimized and validated for bevacizumab (BEV) and cetuximab (CET), as representative examples of the mAbs, using their specific antigens. These antigens were the human vascular endothelial growth factor (VEGF) and epidermal growth factor receptor (EGFR) for BEV and CET, respectively. The limits of detection were 1.28 and 52.64â¯ngâ¯mL-1 for BEV and CET, respectively. The accuracy of the assay was demonstrated with analytical recovery of analytes from spiked plasma at 96.2-104.3 and 96.8-105.3% for BEV and CET, respectively. The precision of the assay was satisfactory as shown by relative standard deviation (RSD) at 2.2-5.7 and 2.5-6.1% for assay of BEV and CET, respectively. The high sensitivity of the assay allowed the use of very small volumes (~ 1⯵L) of plasma sample for analysis. Automated analysis by the proposed KinExA-based assay facilitates the processing of large numbers of mAbs-containing specimens in studies of pharmacokinetics (PK), pharmacodynamics (PD), and therapeutic drug monitoring (TDM) of therapeutic mAbs. The proposed assay can be used to overcome the problems encountered in the existing conventional immunoassays for mAbs.
Assuntos
Antineoplásicos Imunológicos/sangue , Bevacizumab/sangue , Técnicas Biossensoriais/métodos , Cetuximab/sangue , Imunoensaio/métodos , Antineoplásicos Imunológicos/imunologia , Bevacizumab/imunologia , Calibragem , Cetuximab/imunologia , Receptores ErbB/imunologia , Fluoresceína-5-Isotiocianato/química , Fluorescência , Técnica Indireta de Fluorescência para Anticorpo/métodos , Humanos , Imunoglobulina G/imunologia , Limite de Detecção , Fator A de Crescimento do Endotélio Vascular/imunologiaRESUMO
Monitoring the levels of therapeutic antibodies in individual patients would allow patient-specific dose optimization, with the potential for major therapeutic and financial benefits. Our group recently developed a new platform of bioluminescent sensor proteins (LUMABS; LUMinescent AntiBody Sensor) that allow antibody detection directly in blood plasma. In this study, we targeted four clinically important therapeutic antibodies, the Her2-receptor targeting trastuzumab, the anti-CD20 antibodies rituximab and obinutuzumab, and the EGFR-blocking cetuximab. A strong correlation was found between the affinity of the antibody binding peptide and sensor performance. LUMABS sensors with physiologically relevant affinities and decent sensor responses were obtained for trastuzumab and cetuximab using mimotope and meditope peptides, respectively, with affinities in the 10-7 M range. The lower affinity of the CD20-derived cyclic peptide employed in the anti-CD20 LUMABS sensor ( Kd = 10-5 M), translated in a LUMABS sensor with a strongly attenuated sensor response. The trastuzumab and cetuximab sensors were further characterized with respect to binding kinetics and their performance in undiluted blood plasma. For both antibodies, LUMABS-based detection directly in plasma compared well to the analytical performance of commercial ELISA kits. Besides identifying important design parameters for the development of new LUMABS sensors, this work demonstrates the potential of the LUMABS platform for point-of-care detection of therapeutic antibodies.
Assuntos
Anticorpos Monoclonais Humanizados/sangue , Antineoplásicos Imunológicos/sangue , Cetuximab/sangue , Monitoramento de Medicamentos/métodos , Proteínas Luminescentes/análise , Rituximab/sangue , Trastuzumab/sangue , Técnicas Biossensoriais/métodos , Humanos , TermodinâmicaRESUMO
Proteomic approaches using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) without an immunopurification technique have not been applied to the determination of serum cetuximab. This study developed a simple and rapid LC-MS/MS method for the absolute determination of cetuximab in human serum and applied it to clinical settings. Surrogate peptides derived from cetuximab digests were selected using a Fourier transform mass spectrometer. Reduced-alkylated serum cetuximab without immunopurification was digested for 20minutes using immobilized trypsin, and the digestion products were purified by solid-phase extraction. The LC-MS/MS was run in positive ion multiple reaction monitoring mode. This method was applied to the determination of serum samples in head and neck cancer patients treated with cetuximab. The chromatographic run time was 10minutes and no peaks interfering with surrogate peptides in serum digestion products were observed. The calibration curve of absolute cetuximab in serum was linear over the concentration range of 4-200µg/mL. The lower limit of quantification of cetuximab in human serum was 4µg/mL. The intra-assay and inter-assay precision and accuracy were less than 13.2% and 88.0-100.7%, respectively. The serum concentration range of cetuximab was 19-140µg/mL in patients. The serum cetuximab concentrations in LC-MS/MS were correlated with those in ELISA (r=0.899, P <0.01) and the mean bias was 1.5% in cancer patients. In conclusion, the present simple and rapid method with acceptable analytical performance can be helpful for evaluating the absolute concentration of serum cetuximab in clinical settings.
Assuntos
Cetuximab/sangue , Soro/química , Tripsina/química , Calibragem , Cetuximab/uso terapêutico , Cromatografia Líquida/métodos , Neoplasias de Cabeça e Pescoço/sangue , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Humanos , Peptídeos/química , Proteômica/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodosRESUMO
GC1118 is an anti-epidermal growth factor receptor (EGFR) monoclonal antibody that is currently under clinical development. In this study, the pharmacokinetics (PK) of GC1118 were modelled in monkeys to predict human PK and receptor occupancy (RO) profiles. The serum concentrations of GC1118 and its comparator (cetuximab) were assessed in monkeys with a non-compartmental analysis and a target-mediated drug disposition (TMDD) model after intravenous infusion (3-25 mg/kg) of these drugs. The scaling exponent of the EGFR synthesis rate was determined using a sensitivity analysis. The human cetuximab exposures were simulated by applying different exponents (0.7-1.0) for the EGFR synthesis rate in the allometric monkey PK model. Simulated Cmax and area under the curve values therein were compared with those previously reported in the literature to find the best exponent for the EGFR synthesis rate in human beings. The TMDD model appropriately described the monkey PK profile, which showed a decrease in clearance (CL; 1.2-0.4 ml/hr/kg) as the dose increased. The exponents for CL (0.75) and volume of distribution (Vd; 1.0) were used for the allometric scaling to predict human PK. The allometric coefficient for the EGFR synthesis rate chosen by the sensitivity analysis was 0.85, and the RO profiles that could not be measured experimentally were estimated based on the predicted concentrations of the total target and the drug-target complex. Our monkey TMDD model successfully predicts human PK and RO profiles of GC1118 and can be used to determine the appropriate dose for a first-in-human study investigating this drug.
Assuntos
Anticorpos Monoclonais Humanizados/farmacocinética , Antineoplásicos/farmacologia , Receptores ErbB/antagonistas & inibidores , Modelos Biológicos , Animais , Anticorpos Monoclonais Humanizados/sangue , Antineoplásicos/sangue , Cetuximab/sangue , Cetuximab/farmacologia , Simulação por Computador , Relação Dose-Resposta a Droga , Humanos , Macaca fascicularisRESUMO
AIM: This study focuses on the plasma disposition and metabolic activation of capecitabine (CCB) when administered alone or when combined with cetuximab (CTX). PATIENTS AND METHODS: Twenty-four chemo-naïve patients with KRAS wild-type colorectal cancer were randomized into two arms and received either CCB alone (1,000 mg/m(2) bid p.o.), followed by CCB plus CTX (loading dose (LD)=400 mg/m(2) followed by 250 mg/m(2) weekly i.v. maintenance dose) (Arm A; n=12 patients (patients)) or CCB plus CTX followed by CCB alone (Arm B; n=12 patients). Plasma samples were collected from the cubital vein and CCB, 5'-desoxy-5-fluorocytidine (5'-DFCR) and 5'-desoxy-5 fluorouridine (5'-DFUR) were quantified by a sensitive, selective reversed phase high-performance liquid chromatography (HPLC) assay. Non-compartment pharmacokinetic parameters have been calculated by Phoenix WinNonlin. RESULTS: No clinically relevant impact of CTX on CCB pharmacokinetic parameters and metabolic conversion could be detected in both arms after statistical evaluation (ANOVA). CONCLUSION: From the pharmacokinetic point of view, co-administration of CTX to CCB seems to be safe.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Capecitabina/administração & dosagem , Cetuximab/administração & dosagem , Neoplasias Colorretais/tratamento farmacológico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Capecitabina/efeitos adversos , Capecitabina/sangue , Capecitabina/farmacocinética , Cetuximab/efeitos adversos , Cetuximab/sangue , Neoplasias Colorretais/sangue , Neoplasias Colorretais/patologia , Interações Medicamentosas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Proteínas Proto-Oncogênicas p21(ras)/genéticaRESUMO
BACKGROUND: A retrospective study was conducted to analyze interindividual variability of cetuximab pharmacokinetics and its influence on survival (progression-free survival and overall survival [OS]) in a cohort of head and neck squamous cell carcinoma (HNSCC). METHODS: Thirty-four patients received cetuximab as an infusion loading dose of 400 mg/m followed by weekly infusions of 250 mg/m. Twenty-one patients had locally advanced HNSCC, and 13 had metastatic/recurrent HNSCC. Cetuximab concentrations were measured by the enzyme-linked immunosorbent assay, and its pharmacokinetics was analyzed by a population approach. Survivals were analyzed with the log-rank test. RESULTS: Cetuximab pharmacokinetics was best described using a 2-compartment model with both first-order and saturable (zero-order) eliminations. Estimated pharmacokinetic parameters (%CV) were central volume of distribution V1 = 3.18 L (6%), peripheral volume of distribution V2 = 5.4 L (42%), elimination clearance CL = 0.57 L/d (31%), distribution clearance Q = 0.64 L/d, and zero-order elimination rate k0 = 6.72 mg/d (29%). Both V1 and V2 increased with the body surface area. Adjunction of chemotherapy reduced CL and increased k0. OS was inversely related with cetuximab global clearance (P = 0.007) and was higher in patients with severe radiation dermatitis (P = 0.005). CONCLUSIONS: Cetuximab pharmacokinetics in patients with HNSCC can be described using a 2-compartment model combining linear and nonlinear mechanisms of elimination. OS is associated with both cetuximab global clearance and severe radiation dermatitis.
Assuntos
Anticorpos Monoclonais Humanizados/farmacocinética , Carcinoma de Células Escamosas/metabolismo , Cetuximab/farmacocinética , Neoplasias de Cabeça e Pescoço/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/sangue , Anticorpos Monoclonais Humanizados/uso terapêutico , Carcinoma de Células Escamosas/sangue , Carcinoma de Células Escamosas/tratamento farmacológico , Cetuximab/sangue , Cetuximab/uso terapêutico , Intervalo Livre de Doença , Feminino , Neoplasias de Cabeça e Pescoço/sangue , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e PescoçoRESUMO
BACKGROUND: We recently reported the principle of nano-surface and molecular-orientation limited (nSMOL) proteolysis, which is useful for LC-MS bioanalysis of antibody drugs. METHODOLOGY: The nSMOL is a Fab-selective limited proteolysis which utilizes the difference of protease-immobilized nanoparticle diameter (200 nm) and antibody collection resin pore (100 nm). We have demonstrated the full validation for chimeric antibody cetuximab bioanalysis in human plasma using nSMOL. Signature peptides (SQVFFK, ASQSIGTNIHWYQQR and YASESISGIPSR) in cetuximab complementarity-determining region were simultaneously quantitated by LC-MS multiple reaction monitoring. CONCLUSION: This nSMOL quantification showed sensitivity of 0.586 µg/ml and linearity of 0.586 to 300 µg/ml. Full validation study archived the guideline criteria of low Mw drug compounds. These results indicate that nSMOL is also significant method for cetuximab bioanalysis.