Immunohistochemical Evaluation of H-R3 a Novel Humanized Monoclonal Antibody That Neutralizes the EGF-receptor

Pharmacokinetic Evaluation of Nimotuzumab in Patients With Autosomal Dominant Polycystic Kidney Disease

Autosomal dominant polycystic kidney disease (ADPKD) is a genetic disease characterized by an overexpression and mislocalization of epidermal growth factor receptor (EGFR) to the apical membranes of cystic epithelial cells. Nimotuzumab is a humanized antibody that recognizes an extracellular domain III of human EGFR. The aim of this study was to assess the pharmacokinetic behavior of nimotuzumab in patients with ADPKD given as a single dose. A phase I, single-center, and noncontrolled open clinical study was conducted. Five patients were enrolled at each of the following fixed-dose levels: 50, 100, 200, and 400 mg. Intravenous continuous infusions of nimotuzumab were administered every 14 days during a year, except the first administration, when blood samples were drawn during 28 days for pharmacokinetic assessments. Subjects were closely monitored during the trial and at completion of the administration of nimotuzumab, including the anti-idiotypic response. For the first time, nimotuzumab was used for treating a nononcological disease. The administration of nimotuzumab showed dose-dependent kinetics. Nimotuzumab does not develop anti-idiotypic response against the murine portion present in the hypervariable region of the antibody present in the serum of the patients treated. No significant differences were found in the systemic clearance between the 100- and 400-mg dose, which indicates that the optimal biological dose is in this range of dose.

Development and Validation of an Affinity Chromatography-Protein G Method for IgG Quantification

Nimotuzumab, an IgG that recognizes the epidermal growth factor receptor (EGF-R) overexpressed in some tumors, is used in the treatment of advanced head and neck cancer. For the quantification of this protein in cell culture supernatants, protein G-HPLC affinity chromatography is used due to its high affinity and specificity for antibodies of this class. The technique relies on the comparison of the area under the curve of the elution peak of the samples to be evaluated versus to a calibration curve of well-known concentrations and was validated by assessment of its robustness, specificity, repeatability, intermediate precision, accuracy, linearity, limit of detection, limit of quantification, and range. According to results of the study all validation parameters fulfilled the preestablished acceptance criteria and demonstrated the feasibility of the assay for the analysis of samples of cell culture supernatant as well as drug product.

Immunohistochemical Characterization of Three Monoclonal Antibodies Raised against the Epidermal Growth Factor and Its Receptor in Non-Small-Cell Lung Cancer: Their Potential Use in the Selection of Patients for Immunotherapy

Adequate methods to identify which lung cancer patients are most likely to benefit from the targeted drugs against both epidermal growth factor receptor/epidermal growth factor (EGFR/EGF) are needed. For this reason, we evaluated both the tissue reactivity of ior egf/r3 monoclonal antibody (Mab) in human lung carcinomas and its biological activity in NCI-H125 cells. Additionally, we assessed the tissue expression of EGF using two Mabs, CB-EGF1 and CB-EGF2. The overexpression of EGFR was detected in 33.33% and 62.71% of small-cell lung carcinoma (SCLC) and non-small-cell lung carcinoma (NSCLC), respectively. The ability of ior egf/r3 Mab to bind the extracellular domain of EGFR inhibiting cell proliferation and inducing apoptosis in NCI-H125 cells was also demonstrated. The EGF expression was observed in about 17% and 70% of SCLC and NSCLC, respectively. However, differences in the reactivity of CB-EGF1 and CB-EGF2 were evidenced. A dual expression of EGFR and EGF was observed in 16.67% and 57.63% of SCLC and NSCLC patients, respectively. But, a correlation between them was only obtained in NSCLC. Our results permit to recommend the development of diagnostic kits using ior egf/r3 and/or CB-EGF1 Mabs in order to achieve a better selection of patients to EGFR/EGF-targeting treatment.

Nimotuzumab for pediatric diffuse intrinsic pontine gliomas

INTRODUCTION

Diffuse intrinsic pontine gliomas (DIPG) have a poor prognosis: the median survival rate is less than one year. Radiotherapy is the only effective treatment affording an overall survival of 6 - 9 months. So far, no improvement has been achieved with the addition of single/poly-chemotherapy regimens. An urgent need is to advance in this field, from both the biological and the clinical points of view.

AREAS COVERED

Among the few studies providing biological information on DIPG, Gilbertson's group demonstrated a significant increase in EGFR expression. The activity of nimotuzumab, a humanized anti-EGFR monoclonal antibody, was therefore studied within a Phase II trial in 47 relapsing pediatric patients with DIPG and high-grade gliomas, showing an interesting, persistent response, especially in the first group treated. A multicenter exploratory study combining nimotuzumab and radiotherapy showed disease control and an overall patient survival similar to previous experiences along with an improvement in the quality of patient survival and no severe side effects.

EXPERT OPINION

We recommend considering this combination in the armamentarium against DIPG. It might be improved by adding other target drugs/low-toxicity chemotherapy regimens with a synergistic effect with the anti-EGFR component.

Nimotuzumab in pediatric glioma

High-grade gliomas and diffuse brainstem gliomas carry a very poor prognosis despite current therapies, and account together for the largest number of deaths in children with brain tumors. Many of these tumors have been found to overexpress the EGF receptor (EGFR). Nimotuzumab (h-R3) is a humanized monoclonal antibody against the EGFR, and consequently inhibits tyrosine kinase activation. In vitro and in vivo studies have supported the antiproliferative, antiangiogenic, pro-apoptotic and radiosensitizing activities of nimotuzumab. Emerging trials suggest a promising role for nimotuzumab as a therapeutic agent in patients with high-grade gliomas. This review attempts to provide a context for the evolving interest and evidence for nimotuzumab in pediatric glioma.