Phase I clinical trial of the anti-EGFR monoclonal antibody nimotuzumab with concurrent external thoracic radiotherapy in Canadian patients diagnosed with stage IIb, III or IV non-small cell lung cancer unsuitable for radical therapy

Non-Small Cell Lung Cancer Treatment with Molecularly Targeted Therapy and Concurrent Radiotherapy—A Review

Lung cancer is the leading cause of death worldwide for both men and women. Surgery can be offered as a radical treatment at stages I and II and selected cases of stage III (III A). Whereas at more advanced stages, combined modalities of treatment are applied: radiochemotherapy (IIIB) and molecularly targeted treatment (small molecule tyrosine kinase inhibitors, VEGF receptor inhibitors, monoclonal antibodies, and immunological treatment with monoclonal antibodies). Combination treatment, composed of radiotherapy and molecular therapy, is increasingly employed in locally advanced and metastatic lung cancer management. Recent studies have indicated a synergistic effect of such treatment and modification of immune response. The combination of immunotherapy and radiotherapy may result in the enhancement of the abscopal effect. Anti-angiogenic therapy, in combination with RT, is associated with high toxicity and should be not recommended. In this paper, the authors discuss the role of molecular treatment and the possibility of its concurrent use with radiotherapy in non-small cell lung cancer (NSCLC).

Combining radiotherapy with targeted therapies in non-small cell lung cancer: focus on anti-EGFR, anti-ALK and anti-angiogenic agents

The combination of radiotherapy (RT) with targeted agents in non-small cell lung cancer (NSCLC) has been expected to improve the therapeutic ratio and tumor control. The EGFR blockade enhances the antitumor effect of RT. The ALK inhibition elicits anti-proliferative, pro-apoptotic and antiangiogenic effects in ALK-positive NSCLC cell lines, enhanced by the exposure to RT. The antiangiogenic agents normalize pathological tumor vessels, thus decrease tumor cell hypoxia and improve radiosensitivity. To date, however, none of the targeted agents combined with RT has shown proven clinical benefit over standard chemoradiation (CRT) in locally advanced NSCLC. The risk of potential excessive toxicity related to the therapeutic combination of RT and targeted agents cannot be ignored. Well-designed clinical trials may allow development of more effective combination strategies. Another potential application of combined RT and targeted therapies in oncogene-driven NSCLC is metastatic oligoprogressive or oligopersistent disease. The use of RT in oligoprogressive oncogene-driven NSCLC, while continuing first line targeted therapy, can potentially eradicate resistant cell clones and provide survival benefit. Likewise, the consolidation of oligopersistent foci (molecularly resistant to first line targeted therapy) may potentially interfere with the natural course of the disease by avoiding or delaying progression. We discuss here the molecular and radiobiological mechanisms of combining RT and targeted agents, and summarize current clinical experience.

Trial Watch: Tumor-targeting monoclonal antibodies in cancer therapy

In 1997, for the first time in history, a monoclonal antibody (mAb), i.e., the chimeric anti-CD20 molecule rituximab, was approved by the US Food and Drug Administration for use in cancer patients. Since then, the panel of mAbs that are approved by international regulatory agencies for the treatment of hematopoietic and solid malignancies has not stopped to expand, nowadays encompassing a stunning amount of 15 distinct molecules. This therapeutic armamentarium includes mAbs that target tumor-associated antigens, as well as molecules that interfere with tumor-stroma interactions or exert direct immunostimulatory effects. These three classes of mAbs exert antineoplastic activity via distinct mechanisms, which may or may not involve immune effectors other than the mAbs themselves. In previous issues of OncoImmunology, we provided a brief scientific background to the use of mAbs, all types confounded, in cancer therapy, and discussed the results of recent clinical trials investigating the safety and efficacy of this approach. Here, we focus on mAbs that primarily target malignant cells or their interactions with stromal components, as opposed to mAbs that mediate antineoplastic effects by activating the immune system. In particular, we discuss relevant clinical findings that have been published during the last 13 months as well as clinical trials that have been launched in the same period to investigate the therapeutic profile of hitherto investigational tumor-targeting mAbs.

A Review of Monoclonal Antibody-Based Treatments in Non-small Cell Lung Cancer

Non-small cell lung cancer (NSCLC) is one of the most common types of lung cancer worldwide. It metastasizes rapidly and has a poor prognosis. The first-line treatment for most patients is a combination of chemotherapy and radiation. In many subjects, using targeted treatments alongside chemoradiation has shown a better outcome in terms of progression and quality of life for patients. These targeted treatments include small biological inhibiting molecules and monoclonal antibodies. In this review, we have assessed studies focused upon the treatment of non-small cell lung cancer. Some therapies are approved, such as bevacizumab and atezolizumab, while some are still in clinical trials, such as ficlatuzumab and ipilimumab, and others have been rejected due to inadequate disease control, such as figitumumab.

Semi-Mechanistic Pharmacokinetic Model to Guide the Dose Selection of Nimotuzumab in Patients with Autosomal Dominant Polycystic Kidney Disease

Autosomal dominant polycystic kidney disease (ADPKD) is a genetic disease characterized by an overexpression of epidermal growth factor receptor (EGFR). Nimotuzumab is a recombinant humanized monoclonal antibody against human EGFR. The aim of this study was to develop a population pharmacokinetic model for nimotuzumab and to identify demographic and clinical predictive factors of the pharmacokinetic variability. The population pharmacokinetics (PopPK) of nimotuzumab was characterized using a nonlinear mixed-effect modeling approach with NONMEM^®. A total of 422 log-transformed concentration-versus-time datapoints from 20 patients enrolled in a single-center phase I clinical trial were used. Quasi steady state approximation of the full TMDD (target-mediated drug disposition) model with constant target concentration best described the concentration-time profiles. A turnover mediator was included which stimulates the non-specific clearance of mAb in the central compartment in order to explain the reduced levels at higher doses. Covariates had no influence on the PK (pharmacokinetics) parameters. The model was able to detect that the maximum effective dose in ADPKD subjects is 100 mg. The developed PopPK model may be used to guide the dose selection for nimotuzumab during routine clinical practice in patients with polycystic kidney disease. The model will further support the ongoing investigations of the PK/PD relationships of nimotuzumab to improve its therapeutic use in other disease areas.

Targeting Epidermal Growth Factor Receptor in Non-Small-Cell-Lung Cancer: Current State and Future Perspective

BACKGROUND

Lung cancer is one of the leading cause of cancer death worldwide, the most common histological type of lung cancer is non-small cell lung cancer (NSCLC), whose occurrence and development is closely related to the mutation and amplification of epidermal growth factor receptors (EGFR). Currently , a series of targeted drugs were developed on the inhibition of EGFR such as epidermal growth factor receptortyrosine kinase inhibitor EGFR-TKI and monoclonal antibody (McAb).

OBJECTIVE

We sought to summarizes the current drugs targeting Epidermal Growth Factor Receptor in nonsmall- cell-lung.

METHODS

We conducted a comprehensive review of the development and application of EGFR-TKI and McAb which targeted EGFR in NSCLC and compared the mechanisms of PROTAC with the traditional inhibitors.

RESULTS

The drugs targeted EGFR in NSCLC have been widely used in clinic practices. Compared to traditional chemotherapy, these drugs excel with their clear and specific targeting, better curative effects, and less toxic and side effects. However, the mechanism comes with some insurmountable weaknesses like serious toxic and other side effects, as well as proneness to producing drug resistance.

CONCLUSION

The emerging PROTAC (Proteolysis Targeting Chimera) technology has been successfully applied to selective degradation of multiple protein targets, including EGFR. It also highlights the potential and challenges of PROTAC therapy regarding future combination therapeutic options in NSCLC treatment.

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.

Necitumumab for the treatment of advanced non-small-cell lung cancer

Personalized patient-precise medicine is being gradually incorporated into clinical practice for the treatment of non-small-cell lung cancer (NSCLC). The EGFR pathway has been explored as a druggable target with monoclonal antibodies such as cetuximab or necitumumab. Necitumumab is a humanized IgG1 anti-EGFR. In the Phase III SQUIRE trial, necitumumab used as first-line therapy in combination with cisplatin and gemcitabine showed a reduction in risk-of-death and a better disease control rate in advanced squamous NSCLC. Thus, necitumumab is now a new first-line treatment option in squamous NSCLC. However, further biomarker research is needed to improve patient selection. Moreover, necitumumab associated with other immunotherapy and targeted agents is currently an important area of research that may yield better outcomes for NSCLC patients.

EGFR-directed monoclonal antibodies in combination with chemotherapy for treatment of non-small-cell lung cancer: an updated review of clinical trials and new perspectives in biomarkers analysis

Lung cancer still represents one of the most common and fatal neoplasm, accounting for nearly 30% of all cancer-related deaths. Targeted therapies based on molecular tumor features and programmed death-1 (PD-1)/programmed death ligand-1 (PDL-1) blockade immunotherapy have offered new therapeutic options for patients with advanced non-small-cell lung cancer (NSCLC). Activation of the epidermal growth factor receptor (EGFR)-pathway promotes tumor growth and progression, including angiogenesis, invasion, metastasis and inhibition of apoptosis, providing a strong rationale for targeting this pathway. EGFR expression is detected in up to 85% of NSCLC and has been demonstrated to be associated with poor prognosis. Two approaches for blocking EGFR signaling are available: prevention of ligand binding to the extracellular domain with monoclonal antibodies (mAbs) and inhibition of the intracellular tyrosine kinase activity with small molecules. There is a strong rationale to consider the tumor's level of EGFR expression as one of the most significant predictive biomarkers in this setting. In this paper we provide an update focusing on the current status of EGFR-directed mAbs use for the treatment of patients with advanced NSCLC, through a review of all clinical trials involving anti-EGFR mAbs in combination with chemotherapy (CT) for advanced disease and with chemo-radiotherapy for stage III disease. Here we also discuss the current status of predictive biomarkers for anti-EGFR mAbs when added to first-line CT in patients with advanced NSCLC. Finally, we focused on the relevance of EGFR fluorescence in situ hybridization (FISH)+ and immunohistochemistry (IHC)-Score ≥ 200 as predictive biomarkers for the selection of patients who would be most likely to derive a clinical benefit from treatment with CT in combination with anti-EGFR mAbs, with particular reference also to histology.

Synergistic potentiation of the anti-metastatic effect of anti EGFR mAb by its combination with immunotherapies targeting the ganglioside NGcGM3

Several Anti-EGFR mAbs are register for the treatment of human cancer. However, their impact on patients overall survival has been limited by tumor resistance. N-Glycolyl variant of GM3 ganglioside (NGcGM3) is specifically expressed in some human tumors, and it has been associated with a poor prognosis. Several reports have documented that GM3 physically associates to EGFR inhibiting its ligand depend phosphorylation, but it also facilitates an alternative/compensatory signaling cascade mediated by Uroquinase Plasminogen Activator Receptor (uPAR) and integrin α5β1 interaction. However, the difference between NGc and N-Acetylated (NAc) variants of GM3 regarding such interactions is unknown. We hypothesized that enrichment of NGcGM3 expression in tumors relates to advantages of this ganglioside, on ensuring both EGFR and uPAR pathways optimal function. We explored the impact of combining an anti-EGFR (7A7 mAb) with anti-NGcGM3 therapies: NGcGM3/VSSP vaccine or 14F7 mAb. Both combinations synergistically increase overall survival in two models of lung metastasis: 3LL-D122 and 4T1; but combination with NGcGM3/VSSP vaccine is significantly more effective. In 3LL-D122-metastasis, of mice treated with the best combination, both EGFR and uPAR/α5β1 integrin pathways are turn off (I.e expression of uPAR/α5β1; and phosphorylation of EGFR, Stat3, Src and FAK are reduced); and tumor angiogenesis is decreased. Interestingly, combination treatment increases tumor infiltrating CD4⁺T, CD8⁺T and NK⁺-cells. Furthermore, a positive clinical outcome is reported for a cancer patient treated with an anti-EGFR mAb and anti-NGcGM3 therapy. Overall, our results support the combination of anti EGFR antibodies with therapies targeting NGcGM3 to increase their efficacy in future clinical trials.

Antitumor activity of nimotuzumab in combination with cisplatin in lung cancer cell line A549 in vitro

Nimotuzumab, a humanized IgG1 monoclonal antibody against epidermal growth factor receptor (EGFR), increases radiosensitivity in lung cancer. Cisplatin is an effective antitumor agent in lung cancer. In the present study, the antitumor activity of nimotuzumab combined with cisplatin was investigated in A549 lung cancer cells. Viability, cell cycle distribution and cyclin D1 expression were assessed following treatment with nimotuzumab alone, cisplatin alone, nimotuzumab in combination with cisplatin, and nimotuzumab followed sequentially by cisplatin. The inhibitory effect on cell viability of nimotuzumab sequentially followed by cisplatin was higher compared with cisplatin alone (82.17±1.62 vs. 56.97±1.42%). Compared with treatment by cisplatin alone, cell cycle analysis by flow cytometry demonstrated that the percentage of cells in the G₀/G₁ phase was increased when A549 cells were treated with nimotuzumab followed sequentially by cisplatin (P<0.01). However, the proportion of cells in G₀/G₁ phase was decreased when A549 cells were treated with nimotuzumab and cisplatin simultaneously compared with cisplatin alone (P<0.05). Cyclin D1 expression was decreased in all chemotherapy treatment groups; the most significant decrease was in A549 cells treated with nimotuzumab followed sequentially by cisplatin. Nimotuzumab may enhance the antitumor activity of cisplatin on A549 cells. The cell cycle arrest at G₀/G₁ observed may have been due to decreased cyclin D1 levels. Potential antagonism was identified when A549 cells were treated with nimotuzumab and cisplatin simultaneously, indicating that targeted therapy may be more effective when administered prior to conventional chemotherapy.

A randomized, phase II study of gefitinib alone versus nimotuzumab plus gefitinib after platinum-based chemotherapy in advanced non-small cell lung cancer (KCSG LU12-01)

We aimed to evaluate the efficacy of dual inhibition of epidermal growth factor receptor (EGFR) with nimotuzumab (EGFR monoclonal antibody) plus gefitinib (EGFR-tyrosine kinase inhibitor) in advanced non-small cell lung cancer (NSCLC) after platinum-based chemotherapy. An open label, randomized, phase II trial was conducted at 6 centers; 160 patients were randomized (1:1) to either gefitinib alone or nimotuzumab (200 mg, i.v. weekly) plus gefitinib (250 mg p.o. daily) until disease progression or intolerable toxicity. The primary endpoint was progression-free survival (PFS) at 3 months. Of the total 160 enrolled patients, 155 (77: gefitinib, 78: nimotuzumab plus gefitinib) received at least one dose and could be evaluated for efficacy and toxicity. The majority had adenocarcinoma (65.2%) and ECOG performance status of 0 to 1 (83.5%). The median follow-up was 22.1 months, and the PFS rate at 3 months was 48.1% in gefitinib and 37.2% in nimotuzumab plus gefitinib (P = not significant, NS). The median PFS and OS were 2.8 and 13.2 months in gefitinib and 2.0 and 14.0 months in nimotuzumab plus gefitinib. Combined treatment was not associated with superior PFS to gefitinib alone in patients with EGFR mutation (13.5 vs. 10.2 months in gefitinib alone, P=NS) or those with wild-type EGFR (0.9 vs. 2.0 months in gefitinib alone, P=NS). Combined treatment did not increase EGFR inhibition-related adverse events with manageable toxicities. The dual inhibition of EGFR with nimotuzumab plus gefitinib was not associated with better outcomes than gefitinib alone as a second-line treatment of advanced NSCLC (NCT01498562).

A retrospective paired study: efficacy and toxicity of nimotuzumab versus cisplatin concurrent with radiotherapy in nasopharyngeal carcinoma

BACKGROUND

To compare efficacy and toxicity of nimotuzumab versus cisplatin (CDDP) concurrent with intensity modulated radiation therapy (IMRT) in patients with nasopharyngeal carcinoma (NPC).

METHODS

We retrospectively reviewed patients with NPC from September 2008 to November 2013. The synchronous regimens included h-R3/RT (nimotuzumab and radiotherapy) one time per week for 6-8 weeks and CDDP/RT (cisplatin and radiotherapy) every three weeks for 2-3 cycles. All patients in our analysis completed the planned IMRT and received TPF (docetaxel + cisplatin + 5-fluorouracil) neoadjuvant chemotherapy for two cycles.

RESULTS

Among the 302 NPC patients who were treated definitively with TPF neoadjuvant chemotherapy followed by IMRT concurrent with nimotuzumab or cisplatin at West China Hospital Sichuan University, 52 patients received h-R3/RT with complete clinical and follow-up data. Based on age, sex and tumor stage, 104 eligible patients were propensity-matched, with 52 patients in each treatment group (h-R3/RT and CDDP/RT). With a median follow-up of 50 months, the 5-year overall survival (OS) and progression-free survival (PFS) rates for the h-R3/RT vs. CDDP/RT treatment groups were 63.9% vs. 81.4% (p = 0.024) and 58.0% vs. 80.6% (p = 0.028), respectively. The h-R3/RT patients experienced less leukopenia and milder nausea and vomiting. In our sub-analysis, for stage II patients, no significant differences were found in OS and PFS, whereas milder nausea and vomiting were found in the h-R3/RT group (p = 0.046). Moreover, for patients older than 60 years, there were no statistically significant differences in OS and PFS, whereas milder nausea and vomiting was observed in the h-R3/RT group (p = 0.020).

CONCLUSIONS

Although CDDP/RT remains the preferred choice for most patients with NPC, h-R3/RT may be a treatment option for the patients with stage II, older than sixty years old, and who are intolerable to cisplatin.

Targeted therapies for the treatment of non-small-cell lung cancer: Monoclonal antibodies and biological inhibitors

The usual treatments for patients with non-small-cell lung cancer (NSCLC), such as advanced lung adenocarcinoma, are unspecific and aggressive, and include lung resection, radiotherapy and chemotherapy. Recently, treatment with monoclonal antibodies and biological inhibitors has emerged as an effective alternative, generating effective results with few side effects. In recent years, several clinical trials using monoclonal antibodies presented potential benefits to NSCLC, and 4 of them are already approved for the treatment of NSCLC, such as cetuximab, bevacizumab, nivolumab and pembrolizumab. Also, biological inhibitors are attractive tolls for biological applications. Among the approved inhibitors are crizotinib, erlotinib, afatinib and gefitinib, and side effects are usually mild to intense. Nevertheless, biological molecule treatments are under development, and several new monoclonal antibodies and biological inhibitors are in trial to treat NSCLC. Also under trial study are as follows: anti-epidermal growth factor receptor (EGFR) antibodies (nimotuzumab and ficlatuzumab), anti-IGF 1 receptor (IGF-1R) monoclonal antibody (figitumumab), anti-NR-LU-10 monoclonal antibody (nofetumomab) as well as antibodies directly affecting the cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) molecule (ipilimumab and tremelimumab), to receptor activator of nuclear factor-kappa B ligand (RANKL) (denosumab) or to polymerase enzyme (veliparib and olaparib). Among new inhibitors under investigation are poly-ADP ribose polymerase (PARP) inhibitors (veliparib and olaparib) and phosphatidylinositol 3-kinase (PI3K) inhibitor (buparlisib). However, the success of immunotherapies still requires extensive research and additional controlled trials to evaluate the long-term benefits and side effects.

Brain Metastases from NSCLC: Radiation Therapy in the Era of Targeted Therapies

Brain metastases (BMs) will develop in a large proportion of patients with NSCLC throughout the course of their disease. Among patients with NSCLC with oncogenic drivers, mainly EGFR activating mutations and anaplastic lymphoma receptor tyrosine kinase gene (ALK) rearrangements, the presence of BM is a common secondary localization of disease both at the time of diagnosis and at relapse. Because of the limited penetration of a wide range of drugs across the blood-brain barrier, radiotherapy is considered the cornerstone of treatment of BMs. However, evidence of dramatic intracranial response rates has been reported in recent years with targeted therapies such as tyrosine kinase inhibitors and has been supported by new insights into pharmacokinetics to increase rates of tyrosine kinase inhibitors' penetration of the cerebrospinal fluid (CSF). In this context, the combination of brain radiotherapy and targeted therapies seems relevant, and there is a strong radiobiological rationale to harness the radiosentizing effect of the drugs. Nevertheless, to date, there is a paucity of high-level clinical evidence supporting the combination of brain radiotherapy and targeted therapies in patients with NSCLC and BMs, and there are often methodological biases in reported studies, such as the lack of stratification by mutation status. Moreover, among asymptomatic patients not suitable for ablative treatment, this strategy is challenged by the promising results associated with the administration of targeted therapies alone. Herein, we review the biological rationale to combine targeted therapies and brain radiotherapy for patients with NSCLC and BMs, report the clinical data available to date, and discuss future directions to improve outcome in this group of patients.

Molecular targeted therapy to improve radiotherapeutic outcomes for non-small cell lung carcinoma

Effective treatments for non-small cell lung carcinoma (NSCLC) remain elusive. The use of concurrent chemotherapy with radiotherapy (RT) has improved outcomes, but a significant proportion of NSCLC patients are too frail to be able to tolerate an intense course of concurrent chemoradiotherapy. The development of targeted therapies ignited new hope in enhancing radiotherapeutic outcomes. The use of targeted therapies against the epidermal growth factor receptor (EGFR) has offered slight but significant benefits in concurrent use with RT for certain patients in certain situations. However, despite theoretical promise, the use of anti-angiogenics, such as bevacizumab and endostatin, has not proven clinically safe or useful in combination with RT. However, many new targeted agents against new targets are being experimented for combined use with RT. It is hoped that these agents may provide a significant breakthrough in the radiotherapeutic management of NSCLC. The current review provides a brief discussion about the targets, the targeted therapies, the rationale for the use of targeted therapies in combination with RT, and a brief review of the existing data on the subject.

Study on chemotherapeutic sensitizing effect of nimotuzumab on different human esophageal squamous carcinoma cells

Esophageal cancer is one of the leading causes of mortality worldwide. Although, surgery, radio- and chemotherapy are used to treat the disease, the identification of new drugs is crucial to increase the curative effect. The aim of the present study was to examine the chemotherapeutic sensitizing effect of nimotuzumab (h-R3) and cisplatin cytotoxic drugs cisplatin (DDP) and 5-fluorouracil (5-FU) on esophageal carcinoma cells with two different epidermal growth factor receptor (EGFR) expressions. The expression of EGFR was detected in the human EC1 or EC9706 esophageal squamous cell carcinoma cell line using immunohistochemistry. The inhibitory effect of DDP and 5-FU alone or combined with h-R3 on EC1 or EC9706 cell proliferation was detected using an MTT assay. Flow cytometry and the TUNEL assay were used to determine the effect of single or combined drug treatment on cell apoptosis. The results showed that the expression of EGFR was low in EC1 cells but high in EC9706 cells. The inhibitory effect of the single use of h-R3 on EC1 or EC9706 cell proliferation was decreased. The inhibitory effect between single use of h-R3 alone and combined use of the chemotherapy drugs showed no statistically significant difference (P>0.05) on the EC1 cell growth rate, but showed a statistically significant difference (a=0.05) on EC9706 cell growth rate. The results detected by flow cytometry and TUNEL assay showed that the difference between single use of h-R3 alone and the control group was statistically significant with regard to the EC1 apoptosis rate effect (P<0.05), but not statistically significant for EC9706 (P>0.05). However, statistically significant differences were identified in the apoptotic rate of EC9706 cells between the h-R3 combined chemotherapy group and single chemotherapy group (P<0.05), but not on in the EC1 chemotherapy group (P>0.05). In conclusion, the sensitization effect of h-R3 on chemotherapy drugs is associated with the expression level of EGFR in EC1 or EC9706 cells. The cell killing effect of the combined use of h-R3 with DDP and 5-FU showed no obvious synergistic effect compared to the single-drug group, but only an additive effect.

Nimotuzumab enhances radiation sensitivity of NSCLC H292 cells in vitro by blocking epidermal growth factor receptor nuclear translocation and inhibiting radiation-induced DNA damage repair

Background

The epidermal growth factor receptor (EGFR) signaling pathway plays a significant role in radiation resistance. There is evidence that EGFR nuclear translocation is associated with DNA double-strand breaks (DSB) repair. Nimotuzumab has shown the effect of radiosensitization in various cancer cells, but little is known about the relationship between nimotuzumab and EGFR nuclear translocation in non-small cell lung cancer (NSCLC) cell lines. In this study, we selected two NSCLC cell lines, namely, H292 (with high EGFR expression) and H1975 (with low EGFR expression) and explored the mechanisms underlying radiation sensitivity.

Methods

MTT assay, clonogenic survival assay, and flow cytometry were performed separately to test cell viability, radiation sensitivity, cell cycle distribution, and apoptosis. Protein γ-H2AX, DNA-PK/p-DNA-PK, and EGFR/p-EGFR expression were further compared both in the cytoplasm and the nucleus with the western blot.

Results

Nimotuzumab reduced the viability of H292 cells and sensitized H292 cells to ionizing radiation. The radiation sensitivity enhancement ratio (SER) was 1.304 and 1.092 for H292 and H1975 cells, respectively. H292 cells after nimotuzumab administration were arrested at the G0/G1 phase in response to radiation. Apoptosis was without statistical significance in both cell lines. γ-H2AX formation in the combination group (nimotuzumab and radiation) increased both in the cytoplasm and the nucleus along with the decreased expression of nuclear EGFR/p-EGFR and p-DNA-PK in H292 cells (P<0.05) that was more significant than that in H1975 cells.

Conclusion

Our research revealed a possible mechanism to explain the radiosensitivity in H292 cells. Nimotuzumab decreased the radiation-induced activation of DNA-PK by blocking EGFR nuclear translocation and impairing DNA DSB repair, thus enhancing radiosensitivity in H292 cells. Because these results represent early research, the matters of how γ-H2AX and DNA-PK dynamically change simultaneously with nuclear EGFR and the best time to administer nimotuzumab will require further exploration.

Therapeutic integration of new molecule-targeted therapies with radiotherapy in lung cancer

Lung cancer is the most common form of the disease and the leading cause of cancer deaths worldwide. Non-small-cell lung cancer (NSCLC) accounts for approximately 80-85% of all lung cancers. Forty percent of all cases present with stage III, and many of them are considered inoperable (staged IIIA with mediastinal lymph node involvement) or stage IIIB disease. Concurrent platinum-based chemotherapy and thoracic radiation has demonstrated survival benefits in these patients. We review the role of new target agents in combination with radiotherapy in stage III NSCLC. Antiangiogenics improve tumor oxygenation thereby improving the therapeutic efficacy of irradiation in models. Bevacizumab in combination with thoracic radiation has shown high toxicity. However, other antiangiogenic agents are more promising. Radiation activates epidermal growth factor receptor (EGFR) pathways, inducing radioresistance, cell proliferation and enhanced DNA repair. After promising data from preclinical models and early clinical trials, cetuximab did not show any benefit in a recent phase III trial. Panitumumab and nimotuzumab are under evaluation. Gefitinib has been investigated in combination with radiotherapy for unresectable stage III NSCLC, but results in maintenance treatment after chemoradiotherapy were not encouraging. Erlotinib has also been tested in a phase II trial with chemoradiotherapy. Other new pathways and agents are being studied, such as m-TOR pathway, bortezomib, heat shock protein 90 (Hsp90) inhibition, histone deacetylase inhibitors (HDACS), aurora kinases, mitogen activated protein kinases (MARK) and PARP inhibitors.

Necitumumab for the treatment of stage IV metastatic squamous non-small-cell lung cancer

Over the past two decades, progress in the treatment of patients with metastatic squamous non-small-cell lung cancer has been limited. The EGFR is involved in tumor progression and invasion and therefore it has become the target of several studies in lung cancer. Strategies to block this pathway are focused on the development of small molecule (tyrosine kinase inhibitor) and monoclonal antibodies (mAbs). Some mAbs have been studied in patients with advanced non-small-cell lung cancer. For the first time, a fully human immunoglobulin G (IMC-11F8), subclass 1 (IgG1) mAb targeting the EGFR, in combination with standard chemotherapy (cisplatin + gemcitabine), has been shown to increase overall survival in chemo-naïve patients with metastatic confirmed squamous cell histology.

Semimechanistic model to characterize nonlinear pharmacokinetics of nimotuzumab in patients with advanced breast cancer

This study aimed (1) to develop a semimechanistic pharmacokinetic (PK) model for nimotuzumab in patients with advanced breast cancer and (2) to identify demographic, biochemical, and clinical predictive factors of the PK variability. Data from a phase 1 study were analyzed using the nonlinear mixed-effects approach (NONMEM). A target-mediated disposition model that included 2 open PK compartments, the monoclonal antibody (mAb)-target binding, and target and mAb-target complex turnovers best described the linear and nonlinear PK. Covariates had no influence on the PK parameters. The final parameter estimates were 19.93 L (steady-state volume), 0.0045-0.0172 L/h (range of total clearance values), 6.96 μg/mL (steady-state binding constant), 5.50 h(-1) (target degradation rate constant), 1.43 (μg/mL) · h(-1) (complex formation rate), and 0.148 h(-1) (complex internalization rate constant). The model described the effect of the mAb-target binding, and target and mAb-target complex turnovers on nimotuzumab PK. Simulations showed that doses above 200 mg maintained the 50% target occupancy during all of the treatment. This model can be very useful for knowing the dosing schedules required for efficacy and supports further investigation of the pharmacokinetic/pharmacodynamic relationships of nimotuzumab to improve its therapeutic use.

Trial watch: Tumor-targeting monoclonal antibodies for oncological indications

An expanding panel of monoclonal antibodies (mAbs) that specifically target malignant cells or intercept trophic factors delivered by the tumor stroma is now available for cancer therapy. These mAbs can exert direct antiproliferative/cytotoxic effects as they inhibit pro-survival signal transduction cascades or activate lethal receptors at the plasma membrane of cancer cells, they can opsonize neoplastic cells to initiate a tumor-targeting immune response, or they can be harnessed to specifically deliver toxins or radionuclides to transformed cells. As an indication of the success of this immunotherapeutic paradigm, international regulatory agencies approve new tumor-targeting mAbs for use in cancer patients every year. Moreover, the list of indications for previously licensed molecules is frequently expanded to other neoplastic disorders as the results of large, randomized clinical trials become available. Here, we discuss recent advances in the preclinical and clinical development of tumor-targeting mAbs for oncological indications.

Trial watch: Monoclonal antibodies in cancer therapy

During the past 20 years, dozens-if not hundreds-of monoclonal antibodies have been developed and characterized for their capacity to mediate antineoplastic effects, either as they activate/enhance tumor-specific immune responses, either as they interrupt cancer cell-intrinsic signal transduction cascades, either as they specifically delivery toxins to malignant cells or as they block the tumor-stroma interaction. Such an intense research effort has lead to the approval by FDA of no less than 14 distinct molecules for use in humans affected by hematological or solid malignancies. In the inaugural issue of OncoImmunology, we briefly described the scientific rationale behind the use of monoclonal antibodies in cancer therapy and discussed recent, ongoing clinical studies investigating the safety and efficacy of this approach in patients. Here, we summarize the latest developments in this exciting area of clinical research, focusing on high impact studies that have been published during the last 15 months and clinical trials launched in the same period to investigate the therapeutic profile of promising, yet hitherto investigational, monoclonal antibodies.

Combining targeted agents and hypo- and hyper-fractionated radiotherapy in NSCLC

Radical radiotherapy remains the cornerstone of treatment for patients with unresectable locally advanced non small cell lung cancer (NSCLC) either as single modality treatment for poor performance status patients or with sequential or concomitant chemotherapy for good performance status patients. Advances in understanding of tumour molecular biology, targeted drug development and experiences of novel agents in the advanced disease setting have brought targeted agents into the NSCLC clinic. In parallel experience using modified accelerated fractionation schedules in locally advanced disease have demonstrated improved outcomes compared to conventional fractionation in the single modality and sequential chemo-radiotherapy settings. Early studies of targeted agents combined with (chemo-) radiotherapy in locally advanced disease in different clinical settings are discussed below and important areas for future studies are high-lighted.

Nimotuzumab plus chemotherapy versus chemotherapy alone in advanced non-small-cell lung cancer: a multicenter, randomized, open-label Phase II study

Background

The purpose of this study was to evaluate the safety and efficacy of nimotuzumab in combination with chemotherapy (docetaxel and carboplatin) versus chemotherapy alone in patients with stage IIIB/IV non-small-cell lung cancer.

Methods

This multicenter, open-label, Phase II study randomized 110 patients to receive nimotuzumab plus chemotherapy (nimotuzumab group) or chemotherapy alone (control group), and comprised concomitant, maintenance, and follow-up phases. Nimotuzumab 200 mg was administered once weekly for 13 weeks during the first two phases with four cycles of chemotherapy and docetaxel 75 mg/m² and carboplatin (area under the curve 5 mg/mL*min) every 3 weeks for a maximum of four cycles during the concomitant phase. The primary endpoint was objective response rate (sum of complete response and partial response). Secondary endpoints, ie, overall survival and progression-free survival, were estimated using the Kaplan–Meier method. Efficacy was evaluated on the intent-to-treat and efficacy-evaluable sets. Safety was assessed from adverse event and serious adverse event data.

Results

The objective response rate was significantly higher in the nimotuzumab group than in the control group in the intent-to-treat population (54% versus 34.5%; P=0.04). A complete response and partial response were achieved in 3.6% and 50% of patients, respectively, in the nimotuzumab group, and in 4% and 30.9% of patients, respectively, in the control group. No significant differences in median progression-free survival and overall survival were observed. Safety profiles were comparable between the two groups.

Conclusion

Nimotuzumab plus chemotherapy significantly improved the objective response rate as compared with chemotherapy alone. The combination was safe and well tolerated in patients with stage IIIB/IV non-small-cell lung cancer.

Nimotuzumab as a radiosensitizing agent in the treatment of high grade glioma: challenges and opportunities

Nimotuzumab is a humanized monoclonal antibody that binds specifically to human epidermal growth factor receptor, blocking receptor activation. Evidence of its radiosensitizing capacity has been widely evaluated. This article integrates published research findings regarding the role of nimotuzumab in the treatment of high grade glioma in combination with radiotherapy or radiochemotherapy in adult and pediatric populations. First, the mechanisms of action of nimotuzumab and its current applications in clinical trials containing both radiation and chemoradiation therapies are reviewed. Second, a comprehensive explanation of potential mechanisms driving radiosensitization by nimotuzumab in experimental settings is given. Finally, future directions of epidermal growth factor receptor targeting with nimotuzumab in combination with radiation containing regimens, based on its favorable toxicity profile, are proposed. It is hoped that this review may provide further insight into the rational design of new approaches employing nimotuzumab as a useful alternative for the therapeutic management of high grade glioma.

Design and conduct of early-phase radiotherapy trials with targeted therapeutics: lessons from the PRAVO experience

New strategies to facilitate the improvement of physical and integrated biological optimization of high-precision treatment protocols are an important priority for modern radiation oncology. From a clinical perspective, as knowledge accumulates from molecular radiobiology, there is a complex and exciting opportunity to investigate novel approaches to rational patient treatment stratification based on actionable tumor targets, together with the appropriate design of next-generation early-phase radiotherapy trials utilizing targeted therapeutics, to formally evaluate relevant clinical and biomarker endpoints. A unique aspect in the development pathway of systemic agents with presumed radiosensitizing activity will also be the need for special attention on patient eligibility and the rigorous definition of radiation dose-volume relationships and potential dose-limiting toxicities. Based on recent experience from systematically investigating histone deacetylase inhibitors as radiosensitizing agents, from initial studies in preclinical tumor models through the conduct of a phase I clinical study to evaluate tumor activity of the targeted agent as well as patient safety and tumor response to the combined treatment modality, this communication will summarize principles relating to early clinical evaluation of combining radiotherapy and targeted therapeutics.

Targeted therapies in non-small cell lung carcinoma: what have we achieved so far?

The search for innovative therapeutic agents in non-small cell lung cancer (NSCLC) has witnessed a swift evolution. The number of targeted drugs that can improve patient outcomes with an acceptable safety profile is steadily increasing. In this review, we highlight current drugs that have already been approved or are under evaluation for the treatment of patients with NSCLC, either in monotherapy or combined therapy for both the first- and second-line settings. Experience with drugs targeting the vascular endothelial growth factor and its receptor, as well as the epidermal growth factor receptor is summarized. Moreover, we provide an overview of more novel targets in NSCLC and initial experience with the respective therapeutic agents.

Molecularly targeted therapies in locally advanced non-small-cell lung cancer

Approximately a third of the patients with non-small cell lung cancer (NSCLC) present with locally advanced disease not amenable to curative resection. Concurrent chemoradiation is currently the treatment of choice for these patients. Outcomes in patients with locally advanced NSCLC treated with concurrent chemoradiation are modest at best. No significant progress has been made over the past decade in this subset of patients with NSCLC. Several trials have examined the role of molecular targeted therapies in this setting. We review the results of these trials and present the outline of a proposed prospective clinical trial to evaluate targeted drugs in molecularly selected group of patients with locally advanced NSCLC.

A phase I trial of gefitinib and nimotuzumab in patients with advanced non-small cell lung cancer (NSCLC)

BACKGROUND

Nimotuzumab (TheraCIM®) is a humanized anti-epidermal growth factor receptor (EGFR) monoclonal antibody (mAb) with minimal skin toxicity. Combining a different class of anti-EGFR drug with gefitinib is a new strategy to overcome intrinsic and acquired resistance to gefitinib. The aim of this phase I trial was to determine recommended phase II dose (RPIID) and the safety of gefitinib and nimotuzumab combination treatment.

METHODS

Patients with advanced/metastatic NSCLC were treated with escalating doses of weekly nimotuzumab (100mg or 200mg, IV) and fixed doses of daily gefitinib (250 mg/day, PO) until disease progression or unacceptable toxicity. We planned to enroll 10 additional patients at RPIID to ascertain the safety of treatment. EGFR mutations and KRAS mutations were analyzed from available tumor samples.

RESULTS

A total of 16 patients were enrolled (3 in 100mg cohort, 13 in 200mg cohort). Six patients (37.5%) were female, and 5 (31.3%) were never smokers. Adenocarcinoma was the major histologic type (13 patients, 81.3%). Treatment was well-tolerated without dose-limiting toxicity (DLT). Four patients (25.0%) experienced grade 2 skin toxicity (1 in 100mg cohorts, 3 in 200mg cohort). Other common grade 1/2 toxicities were fatigue (37.5%) and diarrhea (25.0%). Among 16 evaluable patients, four patients (25.0%) achieved partial response and 7 patients (43.8%) had stable disease. Two of 4 responders had EGFR mutation (exon 19 deletion).

CONCLUSIONS

Dual agent molecular targeting of EGFR with nimotuzumab and gefitinib in patients with advanced NSCLC is well-tolerated. The RPIID for nimotuzumab is 200mg weekly IV and for gefitinib 250 mg/day PO. Based upon this phase I trial, we are planning to conduct a randomized phase II trial comparing gefitinib and nimotuzumab with gefitinib alone in patients with advanced NSCLC.

Monoclonal antibodies in lung cancer

INTRODUCTION

Lung cancer is the leading cause of cancer death worldwide. As clinical benefits to conventional cancer therapies are still formidable, there is an urgent need for novel agents and approaches to improve the overall clinical outcomes for patients with lung cancer.

AREAS COVERED

This article reviews the current understanding of targeted therapy for lung cancer with monoclonal antibodies (mAbs), mainly bevacizumab and cetuximab. The results from several key clinical trials validating the effectiveness and safety of bevacizumab and cetuximab, the relation of cancer biomarkers, the polymorphic correlation of targeted genes with the therapeutic outcome of mAb-based treatment, as well as the impact of Biomarker-integrated Approaches of Targeted Therapy for Lung Cancer Elimination (BATTLE) trial on personalised treatment of lung cancer are discussed.

EXPERT OPINION

The addition of bevacizumab or cetuximab to chemotherapy has shown promising benefits to the patients with non-small-cell lung cancer. However, the overall benefits of mAb-based targeted therapy to lung cancer patients vary among individuals. It is therefore necessary to define reliable predictive biomarkers in an effort to better identify patients who are most likely to benefit from treatment with these novel agents in lung cancer.

Integration of targeted therapy in the management of locally advanced, unresectable non-small-cell lung cancer

SUMMARY The standard of care for unresectable, locally advanced non-small-cell lung cancer (NSCLC; stage IIIA and IIIB) in the past decade has been concomitant platinum-based chemoradiation therapy. Unfortunately, a plateau has been reached in terms of response and survival rates with the present chemotherapeutic paradigm. Targeted biological agents have significantly altered the treatment landscape for stage IV NSCLC and offer an opportunity to do the same for locally advanced NSCLC. While some early trials using unselected patients have shown modest promise for several biologic agents, the overall data remain mixed. One limitation of these trials has been the lack of patient enrichment based on molecular phenotype most likely to benefit from a particular targeted therapy. This review summarizes the most recent data for select classes of targeted agents being tested in the locally advanced NSCLC setting, and gives insights into future developments in this clinical area.

EGFR inhibition in non-small cell lung cancer: current evidence and future directions

EGFR inhibition has emerged to be an important strategy in the treatment of non-small cell lung cancer (NSCLC). Small molecule tyrosine kinase inhibitors (TKIs) and mono-clonal antibodies (mAbs) to the EGFR have been tested in multiple large randomized phase III studies alone or combined with chemotherapy, as well as small phase I-II studies which investigated their efficacy as radiosensitizers when combined with radiotherapy. In this review, we described the current clinical outcome after treatment with EGFR TKIs and mAbs alone or combined with chemotherapy in advanced stage NSCLC, as well as the early findings in feasibility/phase I or II studies regarding to whether EGFR TKI or mAb can be safely and effectively combined with radiotherapy in the treatment of locally advanced NSCLC. Furthermore, we explore the potential predictive biomarkers for response to EGFR TKIs or mAbs in NSCLC patients based on the findings in the current clinical trials; the mechanisms of resistance to EGFR inhibition; and the strategies of augmenting the antitumor activity of the EGFR inhibitors alone or when combined with chemotherapy or radiotherapy.

Comparative in vitro and experimental in vivo studies of the anti-epidermal growth factor receptor antibody nimotuzumab and its aglycosylated form produced in transgenic tobacco plants

A broad variety of foreign genes can be expressed in transgenic plants, which offer the opportunity for large-scale production of pharmaceutical proteins, such as therapeutic antibodies. Nimotuzumab is a humanized anti-epidermal growth factor receptor (EGFR) recombinant IgG1 antibody approved in different countries for the treatment of head and neck squamous cell carcinoma, paediatric and adult glioma, and nasopharyngeal and oesophageal cancers. Because the antitumour mechanism of nimotuzumab is mainly attributed to its ability to interrupt the signal transduction cascade triggered by EGF/EGFR interaction, we have hypothesized that an aglycosylated form of this antibody, produced by mutating the N(297) position in the IgG(1) Fc region gene, would have similar biochemical and biological properties as the mammalian-cell-produced glycosylated counterpart. In this paper, we report the production and characterization of an aglycosylated form of nimotuzumab in transgenic tobacco plants. The comparison of the plantibody and nimotuzumab in terms of recognition of human EGFR, effect on tyrosine phosphorylation and proliferation in cells in response to EGF, competition with radiolabelled EGF for EGFR, affinity measurements of Fab fragments, pharmacokinetic and biodistribution behaviours in rats and antitumour effects in nude mice bearing human A431 tumours showed that both antibody forms have very similar in vitro and in vivo properties. Our results support the idea that the production of aglycosylated forms of some therapeutic antibodies in transgenic plants is a feasible approach when facing scaling strategies for anticancer immunoglobulins.

Pharmacokinetics and Biodistribution Study of 7A7 Anti-Mouse Epidermal Growth Factor Receptor Monoclonal Antibody and Its F(ab')(2) Fragment in an Immunocompetent Mouse Model

Immunocompetent mice, Fc receptor γ-chain deficient mice (Fcer1g^−/−), and molecular tools as F(ab′)₂ bivalent fragments appear as the most suitable biological models to study the mechanisms of the action of anti-epidermal growth factor receptor (EGFR) monoclonal antibodies (mAbs). In vivo experiments contrasting antitumor effects of whole Abs and their bivalent fragments commonly involve a previous comparative pharmacokinetics study. In this paper, pharmacokinetics and biodistribution of an anti-mouse EGFR Ab were assessed using immunocompetent mice. ¹²⁵I-labeled 7A7 mAb holds an elimination half-life (t_1/2β) of 23.1 h in C57BL/6 mice. Accumulation of mAb was found in liver, spleen, kidneys, and mostly in lungs. We used an ELISA method to determine the t_1/2β of a 7A7 mAb using the same experimental setting. Results from this new analysis revealed a t_1/2β of 23.9 h, supporting this method as a safer and easier system to evaluate pharmacokinetics parameters of mAbs targeting mouse EGFR. Using this system we also studied pharmacokinetics of 7A7 F(ab′)₂ fragment. A tenfold difference between the mAb and fragment t_1/2β was found. These data support the use of the 7A7 F(ab′)₂ fragment in in vivo studies to explore the contribution of the EGFR signaling blockade and the Fc region to the antitumor effect of 7A7 mAb in this autologous scenario.

Targeting the epidermal growth factor receptor in solid tumor malignancies

The epidermal growth factor receptor (EGFR) is over-expressed, as well as mutated, in many types of cancers. In particular, the EGFR variant type III mutant (EGFRvIII) has attracted much attention as it is frequently and exclusively found on many tumor cells, and hence both EGFR and EGFRvIII have been proposed as valid targets in many cancer therapy settings. Different strategies have been developed in order to either inhibit EGFR/EGFRvIII activity or to ablate EGFR/EGFRvIII-positive tumor cells. Drugs that inhibit these receptors include monoclonal antibodies (mAbs) that bind to the extracellular part of EGFR, blocking the binding sites for the EGFR ligands, and intracellular tyrosine kinase inhibitors (TKIs) that block the ATP binding site of the tyrosine kinase domain. Besides an EGFRvIII-targeted vaccine, conjugated anti-EGFR mAbs have been used in different settings to deliver lethal agents to the EGFR/EGFRvIII-positive cells; among these are radio-labelled mAbs and immunotoxins. This article reviews the current status and efficacy of EGFR/EGFRvIII-targeted therapies.

Monoclonal antibodies for the treatment of cancer

Over the past decade, the clinical utility of monoclonal antibodies has been realized and antibodies are now a mainstay for the treatment of cancer. Antibodies have the unique capacity to target and kill tumor cells while simultaneously activating immune effectors to kill tumor cells through the complement cascade or antibody-dependent cellular cytotoxicity (ADCC). This multifaceted mechanism of action combined with target specificity underlies the capacity of antibodies to elicit anti-tumor responses while minimizing the frequency and magnitude of adverse events. This review will focus on mechanisms of action, clinical applications and putative mechanisms of resistance to monoclonal antibody therapy in the context of cancer.

Radiotherapy and "new" drugs-new side effects?

BACKGROUND AND PURPOSE

Targeted drugs have augmented the cancer treatment armamentarium. Based on the molecular specificity, it was initially believed that these drugs had significantly less side effects. However, currently it is accepted that all of these agents have their specific side effects. Based on the given multimodal approach, special emphasis has to be placed on putative interactions of conventional cytostatic drugs, targeted agents and other modalities. The interaction of targeted drugs with radiation harbours special risks, since the awareness for interactions and even synergistic toxicities is lacking. At present, only limited is data available regarding combinations of targeted drugs and radiotherapy. This review gives an overview on the current knowledge on such combined treatments.

MATERIALS AND METHODS

Using the following MESH headings and combinations of these terms pubmed database was searched: Radiotherapy AND cetuximab/trastuzumab/panitumumab/nimotuzumab, bevacizumab, sunitinib/sorafenib/lapatinib/gefitinib/erlotinib/sirolimus, thalidomide/lenalidomide as well as erythropoietin. For citation crosscheck the ISI web of science database was used employing the same search terms.

RESULTS

Several classes of targeted substances may be distinguished: Small molecules including kinase inhibitors and specific inhibitors, antibodies, and anti-angiogenic agents. Combination of these agents with radiotherapy may lead to specific toxicities or negatively influence the efficacy of RT. Though there is only little information on the interaction of molecular targeted radiation and radiotherapy in clinical settings, several critical incidents are reported.

CONCLUSIONS

The addition of molecular targeted drugs to conventional radiotherapy outside of approved regimens or clinical trials warrants a careful consideration especially when used in conjunction in hypo-fractionated regimens. Clinical trials are urgently needed in order to address the open question in regard to efficacy, early and late toxicity.

Nimotuzumab, a novel monoclonal antibody to the epidermal growth factor receptor, in the treatment of non-small cell lung cancer

The epidermal growth factor receptor (EGFR) is a promising therapeutic target in non-small cell lung cancer, and several therapeutic agents that target this receptor, including EGFR tyrosine kinase inhibitors and monoclonal antibodies to EGFR, have been developed. Such monoclonal antibodies have shown efficacy in combination with chemotherapy and radiotherapy. Nimotuzumab (h-R3) is a humanized monoclonal antibody to EGFR, and its effects in combination with radiation have been sufficiently promising to warrant further investigation in several types of cancer. Furthermore, the typical severe dermatologic toxicities associated with other monoclonal antibodies to EGFR have not been observed with nimotuzumab. We here summarize the results of preclinical studies as well as of previous and ongoing clinical trials of nimotuzumab for the treatment of non-small cell lung cancer.

EGFR-Targeting as a Biological Therapy: Understanding Nimotuzumab's Clinical Effects

Current clinical trials of epidermal growth factor receptor (EGFR)-targeted therapies are mostly guided by a classical approach coming from the cytotoxic paradigm. The predominant view is that the efficacy of EGFR antagonists correlates with skin rash toxicity and induction of objective clinical response. Clinical benefit from EGFR-targeted therapies is well documented; however, chronic use in advanced cancer patients has been limited due to cumulative and chemotherapy-enhanced toxicity. Here we analyze different pieces of data from mechanistic and clinical studies with the anti-EGFR monoclonal antibody Nimotuzumab, which provides several clues to understand how this antibody may induce a biological control of tumor growth while keeping a low toxicity profile. Based on these results and the current state of the art on EGFR-targeted therapies, we discuss the need to evaluate new therapeutic approaches using anti-EGFR agents, which would have the potential of transforming advanced cancer into a long-term controlled chronic disease.

The emerging role of nimotuzumab in the treatment of non-small cell lung cancer

Current non-small cell lung cancer (NSCLC) chemotherapy and radiotherapy regimens, although showing definite survival benefit, still leave patients with a disappointing 15% 5-year overall survival rate. Because of the need to improve traditional outcomes, research has focused on identifying specific tumorigenic pathways that may serve as therapeutic targets. The most successful strategies to date are those aimed at the epidermal growth factor receptor (EGFR), which is found to be upregulated in 40%-80% of NSCLC. Several tyrosine kinase inhibitors and monoclonal antibodies (mAbs) have been developed that inhibit the EGFR receptor and have demonstrated clinical benefit in trials as single agents and in combination regimens. Here we discuss one such agent, the mAb nimotuzumab, the background of its development, its clinical experience in NSCLC thus far, and the rationale for expanding its use to other NSCLC treatment settings.