Epidermal Growth Factor Receptor Gefitinib Research Articles

Effects of Gefitinib, an Epidermal Growth Factor Receptor Inhibitor, on Human Placental Cell Growth

Placenta has the highest expression of epidermal growth factor (EGF) receptor of all tissues, a cell signaling pathway promoting survival and growth. Therefore, EGF receptor inhibition could potentially treat ectopic pregnancy. We undertook preclinical studies to examine whether gefitinib (orally available EGF receptor inhibitor) with or without methotrexate inhibits placental cell growth. Gefitinib and methotrexate were added to placental cells and their ability inhibit cell growth, block EGF receptor signaling, and induce apoptosis (programmed cell death) was examined. They were also administered to two animal mouse models to examine their effects on placental tissue in vivo. Epidermal growth factor receptor was highly expressed in placental tissue from ectopic pregnancies. Combining gefitinib with methotrexate potently inhibited growth of placental cells, including placental cell lines (JEG3, BeWo cells) and cells isolated from first-trimester placenta. These drugs were additive in blocking EGF receptor signaling and inducing apoptosis. Gefitinib and methotrexate administered together were more potent in decreasing the volume of human placental cells xenografted subcutaneously onto mice compared with either alone. By day 19 after xenografting, mean (± standard error of the mean), xenograft volumes were: 821 (± 68) mm after gefitinib treatment, 901 (± 204) mm after methotrexate treatment, and 345 (±137) mm after both drugs were given (P<.01 for both comparisons of single therapy compared with combination therapy). Combining these agents doubled rates of fetal resorption in pregnant mice compared with each drug alone. Combining gefitinib with methotrexate potently inhibits placental cell growth in vitro and in mouse models. The combination may have potential in treating ectopic pregnancies.

Single‐arm phase II study of multiagent concurrent chemoradiotherapy and gefitinib in locoregionally advanced squamous cell carcinoma of the head and neck

This phase II study tested the addition of the oral epidermal growth factor receptor gefitinib to multiagent concurrent chemoradiotherapy regimen in head and neck squamous cell cancer (HNSCC). Patients with stage III-IV HNSCC received hyperfractionated radiation (72-74.4 Gy at 120 cGy twice daily), with concurrent 96-hour infusions of cisplatin 20 mg/m(2) /day and fluorouracil 1000 mg/m(2) /day given during weeks 1 and 4. Daily gefitinib 250 mg was started on day 1 of radiation and continued for 2 years. Results were retrospectively compared with our previous study using identical chemoradiotherapy without gefitinib. Sixty patients were enrolled in the study; 80% had stage IV disease and 68% had oropharyngeal primary tumors. The full course of gefitinib was not tolerated by 42%; there were 5 treatment-related deaths (8%). With a median follow-up of 54 months, 2- and 3-year overall survival estimates were 80% and 71%, respectively. Projected distant metastatic control at 2 and 3 years was 88%. When compared with our historical cohort, acute toxicities including renal dysfunction and unplanned rehospitalization were worse in the study patients. Projected outcome estimates did not differ between the 2 cohorts. Addition of gefitinib to concurrent chemoradiotherapy was difficult to complete, did not improve outcomes, and increased toxicity.

Gefitinib for the first-line treatment of locally advanced or metastatic non-small cell lung cancer

This paper presents a summary of the evidence review group (ERG) report into the clinical effectiveness and cost-effectiveness of gefitinib for the first-line treatment of locally advanced or metastatic non-small cell lung cancer, in accordance with the licensed indication, based upon the manufacturer’s submission to the National Institute for Health and Clinical Excellence (NICE) as part of the single technology appraisal process. The submitted clinical evidence consisted of the IRESSA Pan-ASian Study (IPASS); a phase III open-label randomised controlled trial conducted in 87 centres in East Asia which compared the use of gefitinib with paclitaxel/carboplatin in 1217 chemotherapy (CTX)-naive patients with stage IIIB/IV pulmonary adenocarcinoma. The manufacturer’s submission focused on a subgroup of patients in IPASS who were epidermal growth factor receptor (EGFR) gene mutation-positive (M+) (n = 261; 21% of the total IPASS population). The primary clinical outcome was progression-free survival (PFS). Secondary outcomes included overall survival, clinically relevant improvement in quality of life and adverse events (AEs). Cost-effectiveness was measured in terms of incremental cost per quality-adjusted life-year (QALY). In the overall population, PFS was significantly longer in patients treated with gefitinib than in those treated with paclitaxel/carboplatin (hazard ratio 0.74, 95% confidence interval 0.65 to 0.85; p &lt; 0.0001). The manufacturer reported an incremental cost-effectiveness ratio (ICER) of £20,744 per QALY gained for the target population. The probabilistic sensitivity analysis illustrated that for patients who are EGFR M+, gefitinib compared with doublet CTX was not likely to be cost-effective at what would usually be considered standard levels of willingness to pay for an additional QALY; the mean ICER for gefitinib EGFR M+ versus doublet CTX EGFR M+ was reported as £35,700 per QALY. Additional analysis by the ERG included amendments to the base-case analysis, including an alternative approach to projecting survival, inclusion of two important additional comparators, sensitivity to EGFR M+ prevalence, and AE costs and disutilities. The manufacturer’s submission provides clinical evidence to support the use of gefitinib in EGFR M+ patients with adenocarcinoma histology only. Before patients can be offered first-line treatment with gefitinib they must undergo EGFR mutation status testing which is currently not routinely available in the NHS. At the time of writing, the guidance document issued by NICE on 28 July 2010 states that ‘Gefitinib is recommended as an option for the first-line treatment of people with locally advanced or metastatic non-small-cell lung cancer (NSCLC) if they test positive for the epidermal growth factor receptor tyrosine kinase (EGFR-TK) mutation and the manufacturer provides gefitinib at the fixed price agreed under the patient access scheme’.

Gefitinib for the first-line treatment of locally advanced or metastatic non-small cell lung cancer

This paper presents a summary of the evidence review group (ERG) report into the clinical effectiveness and cost-effectiveness of gefitinib for the first-line treatment of locally advanced or metastatic non-small cell lung cancer, in accordance with the licensed indication, based upon the manufacturer's submission to the National Institute for Health and Clinical Excellence (NICE) as part of the single technology appraisal process. The submitted clinical evidence consisted of the IRESSA Pan-ASian Study (IPASS); a phase III open-label randomised controlled trial conducted in 87 centres in East Asia which compared the use of gefitinib with paclitaxel/carboplatin in 1217 chemotherapy (CTX)-naive patients with stage IIIB/IV pulmonary adenocarcinoma. The manufacturer's submission focused on a subgroup of patients in IPASS who were epidermal growth factor receptor (EGFR) gene mutation-positive (M+) (n = 261; 21% of the total IPASS population). The primary clinical outcome was progression-free survival (PFS). Secondary outcomes included overall survival, clinically relevant improvement in quality of life and adverse events (AEs). Cost-effectiveness was measured in terms of incremental cost per quality-adjusted life-year (QALY). In the overall population, PFS was significantly longer in patients treated with gefitinib than in those treated with paclitaxel/carboplatin (hazard ratio 0.74, 95% confidence interval 0.65 to 0.85; p < 0.0001). The manufacturer reported an incremental cost-effectiveness ratio (ICER) of 20,744 pounds per QALY gained for the target population. The probabilistic sensitivity analysis illustrated that for patients who are EGFR M+, gefitinib compared with doublet CTX was not likely to be cost-effective at what would usually be considered standard levels of willingness to pay for an additional QALY; the mean ICER for gefitinib EGFR M+ versus doublet CTX EGFR M+ was reported as 35,700 pounds per QALY. Additional analysis by the ERG included amendments to the base-case analysis, including an alternative approach to projecting survival, inclusion of two important additional comparators, sensitivity to EGFR M+ prevalence, and AE costs and disutilities. The manufacturer's submission provides clinical evidence to support the use of gefitinib in EGFR M+ patients with adenocarcinoma histology only. Before patients can be offered first-line treatment with gefitinib they must undergo EGFR mutation status testing which is currently not routinely available in the NHS. At the time of writing, the guidance document issued by NICE on 28 July 2010 states that 'Gefitinib is recommended as an option for the first-line treatment of people with locally advanced or metastatic non-small-cell lung cancer (NSCLC) if they test positive for the epidermal growth factor receptor tyrosine kinase (EGFR-TK) mutation and the manufacturer provides gefitinib at the fixed price agreed under the patient access scheme'.

PLC and PI3K Pathways are Important in the Inhibition of EGF-lnduced Cell Migration by Gefitinib (‘lressa’, ZD1839)

Expression of epidermal growth factor receptor (EGFR) by human breast cancer tissues is associated with poor clinical response. The EGFR tyrosine kinase inhibitor (EGFR-TKI), gefitinib ('Iressa', ZD1839), is a leading example of a molecular targeted agent, and has an anti-proliferative effect on various cancer cells. But the details of the anti-cancer effect and mechanism have not been elucidated. We studied the anti-cancer effect of gefitinib in breast cancer cell lines and the intracellular pathway downstream of EGFR associated with cell migration. In this study, we analysed the anti-proliferative and anti-migratory effect of gefitinib in EGFR (+) breast cancer cell lines by WST-1 analysis and chemotaxis chamber analysis. We analyzed several intracellular phosphorylated pathways which are activated by mitogen activated kinases (extracellular signal-regulated protein kinase 1 and 2: MEK), phosphatidylinositol 3'-kinase (PI3K) and phpspholipase C (PLC), by blocking those pathways using inhibitors of each kinase, and also investigated the effects on the phosphorylation of myosin light chain (MLC). Gefitinib inhibited proliferation in most of these cell lines. MDA-MB231 was shown to be resistant. Furthermore, proliferation of MDA-MB231 cells was not affected by EGF stimulation, but migration of MDA-MB231 cells was significantly inhibited. PI3K and PLC inhibitors blocked EGF-stimulated cell migration and MLC phosphorylation, but the MEK inhibitor did not influence cell migration. Gefitinib has an anti-migratory effect on MDA-MB231 that results in an anti-proliferative effect. PI3K and PLC are important for the migration of MDA-MB231 cells, and gefitinib may inhibit migration by blocking these signalling pathways.