Anti-epidermal Growth Factor Antibodies Research Articles

Efficacy of anti-epidermal growth factor antibody rechallenge in RAS/BRAF wild-type metastatic colorectal cancer: a multi-institutional observational study

PurposeTo investigate circulating tumor DNA (ctDNA) RAS mutant (MT) incidence before salvage-line treatment and the clinicopathological features and molecular biological factors associated with the efficacy of anti-epithelial growth factor receptor (EGFR) monoclonal antibody (mAb) rechallenge for tissue RAS/BRAF wild type (WT) metastatic colorectal cancer (mCRC).MethodsThis multi-institutional retrospective observational study included 74 patients with mCRC with tissue RAS/BRAF WT refractory to first-line chemotherapy containing anti-EGFR mAb. ctDNA RAS status was assessed using the OncoBEAM™ RAS CRC Kit. We explored the clinicopathological features associated with ctDNA RAS status and the factors related to anti-EGFR mAb rechallenge efficacy in multivariate Cox proportional hazard regression.ResultsThe incidence of RAS MT in ctDNA was 40.5% (30/74), which was associated with primary tumor resection (P = 0.016), liver metastasis (P < 0.001), and high tumor marker levels (P < 0.001). Among the 39 patients treated with anti-EGFR mAb rechallenge, those with ctDNA RAS WT showed significantly longer progression-free survival (PFS) than those with ctDNA RAS MT (median 4.1 vs. 2.7 months, hazard ratio [HR] = 0.39, P = 0.045). Patients who responded to first-line anti-EGFR mAb showed significantly longer PFS (HR = 0.21, P = 0.0026) and overall survival (OS) (HR = 0.23, P = 0.026) than those with stable disease.ConclusionsThe incidence of ctDNA RAS MT mCRC was 40.5%, which was associated with liver metastases and high tumor volumes. Anti-EGFR mAb rechallenge may be effective for patients with mCRC who responded to first-line chemotherapy containing anti-EGFR mAb. No patients with RAS MT in ctDNA responded to anti-EGFR mAb rechallenge.

P-87 A multi-institutional observational study evaluating the efficacy of anti-epidermal growth factor antibody re-challenge in tissue RAS/BRAF wild-type metastatic colorectal cancer

P-87 A multi-institutional observational study evaluating the efficacy of anti-epidermal growth factor antibody re-challenge in tissue RAS/BRAF wild-type metastatic colorectal cancer

Primary tumor location as a predictor of survival in patients with RAS wild-type colorectal cancer who receive molecularly targeted drugs as first-line therapy: a multicenter real-world observational study by the Japanese Society for Cancer of the Colon and Rectum.

Primary tumor location is considered a predictor of overall survival (OS) in RAS wild-type (WT) metastatic colorectal cancer (mCRC) treated with bevacizumab (BEV) or an anti-epidermal growth factor antibody (cetuximab or panitumumab [CET/PAN]) as first-line molecularly targeted therapy. BEV is recommended for right-sided mCRC and CET/PAN for left-sided mCRC based on post-hoc analyses of clinical trial data, but real-world evidence is lacking. We retrospectively collected data of patients who started BEV or CET/PAN plus 5-fluorouracil-based doublet chemotherapy between January 2013 and December 2016 as first-line treatment for RAS WT mCRC at any of 24 Japanese institutions. OS was compared between the BEV and CET/PAN groups according to primary tumor location by Cox multivariate regression analysis in the full cohort and in a propensity score-matched cohort. In total, 935 patients were enrolled. Median OS was 24.6months with BEV and 20.9months with CET/PAN in right-sided mCRC (n = 213; adjusted hazard ratio [HR] 0.73, 95% confidence interval [CI] 0.50-1.06) and 35.7months and 30.0months, respectively, in left-sided mCRC (n = 722; adjusted HR 0.92, 95% CI 0.74-1.13). In the propensity score-matched cohort, OS was significantly better in the BEV group than in the CET/PAN group in right-sided mCRC (HR 0.52, 95% CI 0.28-0.96) but was not significantly different in left-sided mCRC (HR 0.78, 95% CI 0.53-1.07). Real-world data showed that OS was better with BEV than with CET/PAN in right-sided mCRC. However, there was no significant difference in OS in left-sided mCRC.

Impact of Delaying the Addition of Anti-EGFR in First Line of RAS Wild-Type Metastatic Colorectal Cancer: A Propensity-Weighted Pooled Data Analysis.

Simple SummaryThe first-line therapy of patients with RAS wild-type (WT) non-resectable metastatic colorectal cancer (mCRC) is usually 5-fluorouracil-based chemotherapy with either bevacizumab or an anti-epidermal growth factor receptor (EGFR). The introduction of anti-epidermal growth factor antibodies is commonly delayed because of late RAS testing results. Our objective was to evaluate the impact on the overall survival of delayed anti-EGFR introduction strategy. This study compared 305 patients with delayed anti-EGFR introductions, 401 with immediate anti-EGFRs, and 129 with immediate anti-VEGFs. The study suggests that delayed introduction has no deleterious impact on survival compared to the immediate introduction of an anti-EGFR or of an anti-VEGF. The first-line therapy of patients with RAS wild-type (WT) non-resectable metastatic colorectal cancer (mCRC) is usually 5-fluorouracil-based chemotherapy with either bevacizumab or an anti-epidermal growth factor receptor (EGFR). The addition of anti-EGFR antibodies is commonly delayed in clinical practice because of late RAS testing results. Our objective was to evaluate the impact on overall survival (OS) of a delayed anti-EGFR introduction strategy. This study pooled the data of two large retrospective studies. Patients with RAS WT non-resectable mCRC, treated in first line by a doublet chemotherapy with an anti-EGFR introduced with a delay of 2 to 4 cycles, were compared to an anti-EGFR and to an anti-VEGF that was introduced immediately. Patients numbering 305 in the delayed anti-EGFR group, 401 in the immediate anti-EGFR group, and 129 in the immediate anti-VEGF group were analyzed. After propensity scoring, there was no difference between the characteristics of the three groups. Median OS was 28.6 months (95% CI: 23.5–34.1) in the immediate anti-EGFR group, 35.1 (95% CI: 29.9–43.5) in the delayed anti-EGFR group, and 32.4 (95% CI: 25.4–44.8) in the immediate anti-VEGF group. There was no significant difference concerning median OS (p = 0.24) or progression-free survival (p = 0.56). This study suggests that delaying the introduction of an anti-EGFR has no deleterious impact on survival compared to the immediate introduction of an anti-VEGF or of an anti-EGFR.

Chemotherapy and Targeted Agents in the Treatment of Elderly Patients with Metastatic Colorectal Cancer.

Colorectal cancer (CRC) is one of the main causes of cancer death in the elderly. The older patients constitute a heterogeneous group in terms of functional status, comorbidities, and aging-related conditions. Therefore, therapeutic decisions need to be individualized. Additionally, a higher toxicity risk comes from the fact that pharmacokinetics and pharmacodynamics of the drugs as well as the tissue tolerance can be altered with aging. Although the chemotherapy efficacy in metastatic colorectal cancer (mCRC) is similar for older and young patients, more toxicity is presented in the elderly. While the mono-chemotherapy provides the same benefit for young and older patients, doublets front-line chemotherapy improves progression-free survival (PFS) but not overall survival (OS) in the elderly. Furthermore, the benefit of the addition of bevacizumab to chemotherapy in older patients has been shown in several clinical trials, while the clinical data for the benefit of anti-epidermal growth factor antibodies are scarcer. Immunocheckpoint inhibitors could be an appropriate option for patients with microsatellite instability (MSI) tumors. A prior geriatric assessment is required before deciding the type of treatment in order to offer the best therapeutic option.

Abstract CT130: Evidence for synergistic immune responses in the first-in-human (FIH) combination of B cell-activating immunotherapy (IO) with anti-PD1 immune checkpoint inhibitor nivolumab (N) as 2nd-line therapy in patients (pts) with advanced non-small cell lung cancer (aNSCLC)

Abstract Introduction: While combined immunotherapeutic activation of B and T cells is predicted to synergistically enhance both humoral and cell-mediated immunity, this has not been previously tested in human cancer patients. To assess this, we conducted the FIH trial combining B cell-activating IO (CIMAvax-EGF (C)) with T cell-activating IO (PD-1 blockade with nivolumab (N)). C activates B cells to produce endogenous anti-epidermal growth factor (EGF) antibodies (Abs) that deplete EGF from circulation. As a single agent maintenance therapy in aNSCLC, C prolonged overall survival (OS) in a randomized phase III trial. We now present immune correlates of improved OS with this novel combination. Methods: We reported safety and preliminary efficacy data from 13 pts from the phase I study of C+N (AACR 2019). Serial blood samples were analyzed by Luminex for dynamic changes in circulating cytokines and proteins implicated in EGF signaling, and by flow cytometry for peripheral blood mononuclear cell immunophenotype. Cox regression analysis was used to analyze association with OS. Results: 71% of pts achieved anti-EGF Ab titers of &amp;gt;1:4000 after 3 doses of C, compared to historical controls of 39% with C alone. Baseline increase in CD8+ naive T cells, memory B cells, and decrease in MDSC and Th17 T cells all significantly correlated with better OS. Baseline increase of inflammatory cytokines/markers (IL7, IL15, IFNα, IL8, sCD40L and CRP) significantly correlated with worse OS. Despite enrichment for pts with tumor proportion score (TPS) PD-L1 0%, median OS (mOS) of the intent-to-treat population (pts who received at least 1 dose of C+N, n=13) was 13.7 months (mo) vs. 9.9 mo in Checkmate 057 aNSCLC pts with tumor proportion score (TPS) PD-L1 &amp;lt;10%. mOS of per-protocol pts (all 4 loading doses of C+N given over 8 weeks, n=11) was 18.5 mo. In contrast to Checkmate 057 results, where OS benefit of N favored aNSCLC with KRAS mutation (KRASm), C+N showed better mOS of 22.4 mo in EGFR/ALK/KRAS wildtype (wt) pts versus 12.3 mo in KRASm/STKwt pts. Conclusion: This study provides evidence for synergistic effects of combining B and T cell activating IO in aNSCLC pts. C+N generated higher anti-EGF titers in more pts at an earlier time point vs. C alone, which is the first demonstration in pts of enhancement of Ab responses by immune checkpoint blockade. Immune analysis identified new specific immune cell populations and inflammatory markers that significantly correlate with OS with C+N that have not been previously identified with C or N as single agents. C+N improved OS compared to historical controls of aNSCLC pts receiving N in phase III trials. Of particular note, C+N showed better OS in pts with EGFR/ALK/KRAS wt aNSCLC versus KRASm/STKwt pts. The Phase II portion of the study is ongoing. Citation Format: Tania Crombet, Jason Muhitch, Circe Mesa, Rachel Evans, Danay S. Hernandez, Patricia L. Luaces, Zaima Mazorra, Orestes Morales, Carlos Cedeno, Aileen Cinquino, Daniel T. Fisher, Kelvin Lee, Mary Reid, Grace Dy. Evidence for synergistic immune responses in the first-in-human (FIH) combination of B cell-activating immunotherapy (IO) with anti-PD1 immune checkpoint inhibitor nivolumab (N) as 2nd-line therapy in patients (pts) with advanced non-small cell lung cancer (aNSCLC) [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr CT130.

Controverse autour de la ventilation non invasive au cours de l’insuffisance respiratoire aiguë hypoxémique: Controversy around non invasive ventilation in hypoxemic acute respiratory failure

Systemically injected drug delivery systems distribute into various organs and tissues, including liver, spleen and kidneys. Recent reports pointed out a significant accumulation of systemically injected nanoparticles in the skin. Skin constitutes the largest organ in the body with important immune functions, and accumulation of drug delivery systems could have significant implications for skin toxicity in living subjects. Fiber optic-based near-infrared spectroscopy (FONIRS) setup was developed and tested for measuring of NIR (760 nm excitation) emission spectra in the skin. Ex vivo spectral measurements of NIR fluorescence through the skin showed linear response down to 34 femtomole of dye DiR. Following systemic injection of IRDye 800 labeled 500 kDa dextran, FONIRS detected an immediate and stable accumulation of fluorescence in the skin. Longitudinal monitoring of skin accumulation and elimination of IRDye 800-labeled therapeutic anti-epidermal growth factor antibody (cetuximab) showed significant signal in the skin after the antibody cleared from circulation. Comparison of skin accumulation of DiR labeled, long-circulating PEGylated liposomes with short-circulating non-PEGylated liposomes showed much higher accumulation of PEGylated liposomes that persisted several days after the liposomes cleared from blood. Measurements with FONIRS enabled to estimate skin concentration of liposomes (percent of injected dose per gram). This simple and practical approach can be used to monitor accumulation of drug delivery systems in preclinical and clinical studies.

Longitudinal monitoring of skin accumulation of nanocarriers and biologicals with fiber optic near infrared fluorescence spectroscopy (FONIRS)

Systemically injected drug delivery systems distribute into various organs and tissues, including liver, spleen and kidneys. Recent reports pointed out a significant accumulation of systemically injected nanoparticles in the skin. Skin constitutes the largest organ in the body with important immune functions, and accumulation of drug delivery systems could have significant implications for skin toxicity in living subjects. Fiber optic-based near-infrared spectroscopy (FONIRS) setup was developed and tested for measuring of NIR (760nm excitation) emission spectra in the skin. Ex vivo spectral measurements of NIR fluorescence through the skin showed linear response down to 34 femtomole of dye DiR. Following systemic injection of IRDye 800 labeled 500kDa dextran, FONIRS detected an immediate and stable accumulation of fluorescence in the skin. Longitudinal monitoring of skin accumulation and elimination of IRDye 800-labeled therapeutic anti-epidermal growth factor antibody (cetuximab) showed significant signal in the skin after the antibody cleared from circulation. Comparison of skin accumulation of DiR labeled, long-circulating PEGylated liposomes with short-circulating non-PEGylated liposomes showed much higher accumulation of PEGylated liposomes that persisted several days after the liposomes cleared from blood. Measurements with FONIRS enabled to estimate skin concentration of liposomes (percent of injected dose per gram). This simple and practical approach can be used to monitor accumulation of drug delivery systems in preclinical and clinical studies.

Role of Biologics in First-Line Treatment of Colorectal Cancer.

In the past decade, significant advances have been made in the treatment of advanced colorectal cancer. Multiple cytotoxic agents and targeted therapies have been approved for management of metastatic colorectal cancer, leading to improvement of median overall survival in clinical trials to more than 30 months. Of note, before the introduction of biologics into treatment algorithms for metastatic colorectal cancer, median survival in phase III trials never exceeded 24 months. In 2016, the most common treatment approach in first line is a combination of chemotherapy with a biologic agent. The choice of therapy is influenced by patient factors (eg, age, comorbidities), tumor characteristics (eg, overall tumor burden, pattern of metastatic spread, mutation signature), potential adverse effects of therapy, and goals of treatment. The choice between irinotecan- or oxaliplatin-based cytotoxic chemotherapy regimen is primarily based on differential toxicity profile because they have similar efficacy. Currently, three biologic agents-bevacizumab, cetuximab, and panitumumab-are approved for first-line treatment of metastatic colorectal cancer. For patients with mutant RAS and likely mutant BRAF V600E tumors, bevacizumab is the only biologic agent that can be used in conjunction with cytotoxic chemotherapy. The choice of anti-epidermal growth factor antibody or anti-vascular endothelial growth factor antibody in RAS wild-type tumors is based on the specific clinical scenario. Recently, some clinical and molecular biomarkers have emerged that may help in decision making. In this review, we discuss the role of biologics in the management of first-line treatment of metastatic colorectal cancer.

Abstract 2368: Inhibition of epidermal growth factor receptor pathway by epidermal growth factor antibodies in non-small cell lung cancer

Abstract Introduction: The Epidermal Growth Factor Receptor (EGFR) signaling system is frequently unbalanced in non-small-cell lung cancer (NSCLC). Epidermal Growth Factor (EGF) could be an attractive target in these tumors. We used a “cancer vaccine” composed of human recombinant EGF conjugated to a carrier protein P64K. The vaccine is intended to induce antibodies against patients’ own EGF that would block EGF-EGFR interaction. Objectives: In NSCLC cell lines we assessed whether anti-EGF antibodies can inhibit the pathway activated by EGF-EGFR binding and whether sera from immunized patients can block downstream key signal transduction proteins. NSCLC cell lines were selected to determine whethergenetic alterations in EGFR, KRAS, ALK, BRAF or MET can have an impact on inhibition of EGFR pathway by anti-EGF antibodies. Experimental Procedures: Western blotting was used to evaluate the capacity of antibodies and sera from patients to inhibit EGFR activation pathway. MTT assays were performed to evaluate the effects on tumor cell proliferation. Results: The anti-EGF antibodies showed a dose-dependent inhibitory effect on EGF-induced activation of EGFR and downstream pathway molecules such as Akt and ERK 1/2. This inhibition was observed in all cell lines tested, including KRAS, EGFR and BRAF mutated cells as well as cells with ALK translocations or MET amplification. Sera from 10 patients immunized with the P64K-EGF vaccine were then tested. All sera reversed EGF-induced activation of EGFR and ERK 1/2, but some sera were significantly more potent than others. By contrast, two control sera from non-vaccinated patients failed to inhibit EGF-induced phosphorylation of EGFR and ERK 1/2. Finally, anti-EGF antibodies were also able to block the stimulatory effects of EGF on the growth of some NSCLC cell lines. Conclusions: Anti EGF antibodies and sera from patients immunized with an “EGF vaccine”, called otherwise EGF Pathway Targeted Immunization inhibits EGFR signaling in NSCLC cell line models. This effect is independent of cells’ genetic background. Citation Format: Jordi Codony-Servat, Miguel Angel Molina-Vila, Jordi Bertran-Alamillo, Rafael Rosell, Erik D’Hondt. Inhibition of epidermal growth factor receptor pathway by epidermal growth factor antibodies in non-small cell lung cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2368.

Impact of first-line bevacizumab therapy on the efficacy of subsequent anti-epidermal growth factor antibodies (anti-EGFR) in metastatic colorectal cancer (mCRC).

685 Background: The FIRE3 study reported that cetuximab added to first line combination chemotherapy versus the addition of bevacizumab to the same chemotherapy backbone, with a planned switch to the alternative biologic in second line therapy, resulted in improved overall survival. One possible explanation is that the sequence of biologic administration in mCRC impacts on treatment benefit. Examination of the efficacy of anti-EGFR therapy in cohorts where patients have and have not received prior bevacizumab will inform this. Methods: We interrogated our prospective database (ACCORD), which records comprehensive detail on demographics, treatments received and patient outcomes for consecutive mCRC patients in real world practice across multiple institutions in Australia. We included patients receiving 2nd and subsequent line anti-EGFR monotherapy. Disease control rate (DCR) (partial response plus stable disease), progression free survival (PFS) and overall survival (OS) from the start of anti-EGFR were determined as a function of prior bevacizumab use. Results: From a total of 1511 patients treated between 01/10/2002 and 31/12/2014,129 patients treated with single agent anti- EGFR were identified, 75 had received prior bevacizumab. Demographics, performance status and tumour characteristics were similar between the 2 groups. 84% were confirmed KRAS exon 2 wild type. Prior treatment with bevacizumab did not impact DCR (35% vs 40%, p = 0.5065), median PFS (3.0 vs 3.0 months, p = 0.9460) or OS (8.6 vs 8.4 months, HR 0.95, p = 0.8073). Similarly, for bevacizumab treated patients, the time since last dose of bevacizumab to start of anti-EGFR ( &lt; 3 months (n = 26) vs 3-6 months (n = 17) vs &gt; 6 months (n = 32)) did not impact PFS (2.3 vs 3.6 vs 3 months) or OS (8.9 vs 10.1 vs 7.1 months, HR: 0.88, p = 0.82). Conclusions: There was no evident impact of previous bevacizumab treatment, or time from previous bevacizumab treatment, on the efficacy of single agent anti-EGFR therapy in a routine clinical practice cohort. Our data do not support the notion that prior bevacizumab renders tumors more or less sensitive to subsequent anti EGFR therapy.

A Case of Sigmoid Colon Cancer in which Somatic Pain was Rapidly Alleviated after Panitumumab Administration Despite Tumor Progression

We present a 72-year-old woman with sigmoid colon cancer in whom the somatic pain was alleviated rapidly after the administration of anti-epidermal growth factor antibodies. Our patient had received 4 cycles of FOLFIRI therapy (irinotecan, 5-fluorouracil, and leucovorin) in combination with panitumumab (Pmab) for the treatment of unresectable primary cancer accompanied with multiple liver metastases and peritonitis carcinomatosa. As grade 3 paronychia eventually occurred, chemotherapy was stopped. After recovery of the grade 3 paronychia, Pmab was re-introduced and administered every alternate cycle to reduce the extent of adverse events. The patient had complained of somatic pain in the lower right abdomen just before re-initiating Pmab administration. The pain intensity decreased immediately after the administration of Pmab. On the next day her pain had remarkably alleviated and she was free from pain for a week. This phenomenon was repeatedly observed. After the re-introduction of Pmab, tumor response was evaluated on computed tomography, which showed progressive disease. We demonstrated that Pmab was effective in the alleviation of somatic pain, although the size of the tumors gradually increased.

Pathological assessment of colon cancer specimens

Pathologists play an important role in the treatment of colon cancer by undertaking a meticulous pathological assessment and producing an optimal pathological report. The specimens should be photographed and the plane of surgery described to provide a permanent record of the quality of surgery. The recommended grading system has been shown to predict patient outcome. In addition, pathologists should assess the degree of central radicality to determine whether complete mesocolic excision (CME) has been undertaken. The specimen should then be carefully dissected to ensure that all of the potential high-risk features are assessed, including the status of the non-peritonealised resection margin and the presence or absence of extramural venous invasion. All of the lymph nodes within the specimen should be examined and ancillary techniques used if required. Finally, molecular pathology is now an important component of patient management and laboratories should have access to immunohistochemistry for the mismatch repair proteins to identify microsatellite instability, and also sequencing technologies to determine the mutational status of KRAS , NRAS and BRAF genes for patients being considered for antiepidermal growth factor antibody treatment.

Features of ovarian cancer in Lynch syndrome (Review).

Lynch syndrome is a hereditary ovarian cancer with a prevalence of 0.9-2.7%. Lynch syndrome accounts for 10-15% of hereditary ovarian cancers, while hereditary breast and ovarian cancer syndrome accounts for 65-75% of these cancers. The lifetime risk for ovarian cancer in families with Lynch syndrome is ~8%, which is lower than colorectal and endometrial cancers, and ovarian cancer is not listed in the Amsterdam Criteria II. More than half of sporadic ovarian cancers are diagnosed in stage III or IV, but ≥80% of ovarian cancers in Lynch syndrome are diagnosed in stage I or II. Ovarian cancers in Lynch syndrome mostly have non-serous histology and different properties from those of sporadic ovarian cancers. A screening method for ovarian cancers in Lynch syndrome has yet to be established and clinical studies of prophylactic administration of oral contraceptives are not available. However, molecular profiles at the genetic level indicate that ovarian cancer in Lynch syndrome has a more favorable prognosis than sporadic ovarian cancer. Inhibitors of the phosphatidylinositol 3-kinase/mammalian target of the rapamycin pathway and anti-epidermal growth factor antibodies may have efficacy for the disease. To the best of our knowledge, this is the first review focusing on ovarian cancer in Lynch syndrome.

Clinical Outcome of Japanese Metastatic Colorectal Cancer Patients Harbouring the KRAS p.G13D Mutation Treated with Cetuximab + Irinotecan

Metastatic colorectal cancer with KRAS codon 12 or 13 mutations is not currently treated with anti-epidermal growth factor antibodies. A recent retrospective study in Western countries raised the possibility that KRAS p.G13D mutation may not be absolutely predictive of non-response compared with other KRAS mutations from the findings of longer overall survival and progression-free survival following cetuximab treatment. We retrospectively investigated the relationship between KRAS status and cetuximab efficacy among Japanese patients. Data of 109 patients from nine institutions in Japan were retrospectively analysed. All patients were refractory or intolerant to fluoropyrimidine, oxaliplatin and irinotecan, and they were treated with a cetuximab + irinotecan regimen. The response rate, disease control rate, progression-free survival and overall survival were compared according to KRAS status. Overall, 76 (70%), 7 (6%) and 26 (24%) patients had KRAS wild-type, KRAS p.G13D and other KRAS mutations. Their various parameters were as follows: response rate: 30% (23/76), 14% (1/7) and 0% (0/26); disease control rate: 71% (54/76), 71% (5/7) and 54% (14/26); median progression-free survival: 4.6 months (95% confidence interval, 2.8-6.3), 4.1 months (0-9.9) and 2.1 months (1.5-2.8); and median overall survival: 11.2 months (6.4-16.0), 8.5 months (5.3-11.8) and 6.8 months (4.1-9.6), respectively. Although no statistically significant difference in progression-free survival or overall survival was observed between KRAS p.G13D-mutant and other mutant tumours, the disease control rate was higher in KRAS p.G13D-mutant patients and a partial response was observed in one such patient. Our study suggested that cetuximab showed some activity inKRAS p.G13D-mutant colorectal cancer patients. Further research is warranted.

Treatment of malignant, non-resectable, epithelial origin esophageal tumours with the humanized anti-epidermal growth factor antibody nimotuzumab combined with radiation therapy and chemotherapy.

Background: Over-expression of epidermal growth factor receptor in esophageal cancer is associated with poor prognosis. The present study was conducted to evaluate safety and preliminary efficacy of nimotuzumab, a humanized anti-EGFR antibody in combination with radiation and chemotherapy in advanced esophageal tumours.Patients and Methods: A Phase II clinical trial was conducted, where patients received cisplatin, 5-fluorouracil, and radiotherapy, either alone or combined with six weekly infusions of nimotuzumab at the dose of 200 mg. Safety was the primary endpoint. The antitumoral objective response rate was the secondary endpoint. Epidermal growth factor receptor expression, KRAS mutation status and anti-idiotypic response were also evaluated.Results: Sixty-three patients were included in the study. Thirty patients were entered into the control group, and thirty-three patients received the treatment with nimotuzumab. The antibody was very well tolerated. Objective response rate was 47.8 % (nimotuzumab group) and 15.4 % (control group). Disease control rate was 60.9 % (nimotuzumab group) and 26.9 % (control group). Response and disease control rate were higher in patients with EGFR overexpressing tumors.Conclusion: Nimotuzumab plus chemoradiotherapy was safe and provided statistically significant objective response. A Phase III in patients with similar characteristics will be launched.

KRAS mutations detected by the amplification refractory mutation system–Scorpion assays strongly correlate with therapeutic effect of cetuximab

Background:We aimed to compare the sensitive and quality-controlled KRAS testing with direct sequencing and to assess the impact on decision making of treatment.Patients and methods:We analysed genomic DNA isolated from macrodissected formalin-fixed paraffin-embedded specimens by direct sequencing and an amplification refractory mutation system–Scorpion assay (ARMS/S) method. Cetuximab was administered to patients identified as having wild-type (WT) KRAS using direct sequencing. Therapeutic effects were evaluated according to their KRAS status as determined by ARMS/S.Results:Among the 159 patients, the overall mutation rate was determined to be 37.0% by direct sequencing and 44.0% by ARMS/S. For the patients diagnosed as WT by direct sequencing and treated with cetuximab (n=47), a response rate of 16.0% was observed for 38 ARMS/S WT patients, whereas 9 ARMS/S mutant (MUT) patients failed to respond. The ARMS/S WT patients showed significant improvement in progression-free survival (PFS) and overall survival (OS) compared with ARMS/S MUT patients (PFS median 5.0 vs 1.7 months, hazards ratio (HR)=0.29, P=0.001; OS median 12.1 vs 3.8 months, HR=0.26, P=0.001).Conclusion:Sensitive and quality-controlled KRAS testing may provide improved predictive power to determine the efficacy of anti-epidermal growth factor antibodies.

Are Vaccines Making a Comeback in Non–Small-Cell Lung Cancer?

For decades we have investigated immune-based therapies in other types of cancer, namely melanoma, prostate, renal cell, nonHodgkin’s lymphoma, bladder cancer, and renal cell carcinoma. However, lung cancer has historically not been considered to be an immunogenic group of tumors. Therefore, the foundation of any lung cancer immunotherapy must rest on a solid rationale for activating and directing the immune system to recognize subtle differences between cancer cells and normal cells. The article by Neninger Vinageras et al focuses on the successes of therapies targeting epidermal growth factor receptor to identify one such difference. The results support a unique strategy involving both immune activation and targeted therapy. The investigators constructed a conjugated vaccine product involving a yeast-derived human recombinant epidermal growth factor (EGF) protein and an Escherichia coli– derived P64K Neisseria meningitides protein. Within 4 weeks of completion of frontline platinum-based chemotherapy advanced non–small-cell lung cancer (NSCLC), patients (50 stage IIIB; 30 stage IV) were randomly assigned to receive vaccine or supportive care. Results demonstrated significant correlation of survival in the vaccinated patients (n 40) to two surrogate parameters: induction of anti EGF antibodies (immune effect) and reduction in serum EGF concentration (targeted effect). Results also suggested overall survival advantage in vaccine-treated patients compared with controls at 60 years or younger. Historically, there have been several hypotheses to explain potential lack of anticancer immune activity in NSCLC. These include ineffective priming of tumor-specific T cells, lack of high-avidity of primed tumor-specific T cells, and physical or functional disabling of primed tumor-specific T cells by the primary host and or tumorrelated mechanism. For example, in NSCLC a high proportion of the tumor-infiltrating lymphocytes are immunosuppressive T regulatory cells (CD4 CD25 ) that secrete transforming growth factor(TFG) and express a high level of cytotoxic T-lymphocyte antigen4. These cells have been shown to impede immune activation by facilitating T-cell tolerance to tumor associated antigens rather than cross-priming CD8 T cells resulting in the nonproliferation of killer T cells that recognize the tumor without attacking it. Elevated levels of interleukin (IL)-10 and TFGare found in patients with NSCLC. Animal models have shown immune suppression is mediated by these cytokines serving as a defense for malignant T cells against the body’s immune system. Other vaccines in NSCLC have focused on methods of enhancing tumor antigen recognition. Most notable approaches already involved in phase III investigation in NSCLC include Belagenpumatucel-L, L-BLP 25, and MAGE-3 vaccines. Belagenpumatucel-L is a nonviral gene-based allogeneic vaccine that incorporates the TFG2 antisense gene into a cocktail of four different NSCLC cell lines. A recent randomized phase II trial involving 75 patients was recently completed. A dose-related survival advantage to belagenpumatucel-L was demonstrated. Furthermore, patients who achieved stable disease or better with vaccination had increased production of relevant immunostimulatory cytokines (interferon; IL-6; IL-4) and positive clinical outcomes were correlated with development of human leukocyte antigen antibody response as well as T-lymphocyte activation. The L-BLP 25 liposome vaccine consists of a lipoprotein that is slightly larger that one tandem-repeat of the MUC1 backbone and an immunoadjuvant, monophosphoral lipid-A contained in a liposomal formulation. Trials of the L-BLP-25 vaccine in stage III and IV NSCLC patients demonstrated safety of the vaccine but did not demonstrate a statistically significant survival benefit. However, a subset of patients (n 75) with IIIB disease demonstrated a trend towards improved survival (P . 09). MAGE-3 is aberrantly expressed in a wide variety of tumors, including NSCLC. Several CD8 T-cell epitopes of MAGE-3 have been identified in vitro. Based on these findings, synthetic peptides corresponding to these epitopes have been introduced into clinical vaccination studies. A recent randomized phase II trial was conducted involving 182 stage IB or II NSCLC MAGE-A3 positive patients (122 vaccine and 60 placebo). Results demonstrated a trend towards improved survival in the stage II patients receiving the vaccine compared with placebo. Within the next two years it is likely that the phase III trials involving belagenpumatucel-L, MAGE-3 vaccine and L-BLP 25 will be completed. Other vaccines in NSCLC demonstrating evidence of activity in phase I/II trials include GVAX, B7.1, EP2101, L523S and telomerase GV1001. It is hoped that over the next few years our knowledge of the immune system’s role against cancer will further improve and our clinical experience with the use of various vaccines involving different stages of disease in NSCLC will enable a “toolbox” of these nontoxic therapeutics to be expanded into the management of NCSLC.

Effective Inhibition of the Epidermal Growth Factor/Epidermal Growth Factor Receptor Binding by Anti–Epidermal Growth Factor Antibodies Is Related to Better Survival in Advanced Non–Small-Cell Lung Cancer Patients Treated with the Epidermal Growth Factor Cancer Vaccine

Epidermal growth factor (EGF) might be a suitable immunotherapeutic target in non-small-cell lung cancer (NSCLC). Our approach consists of active immunotherapy with EGF. The aim of the study is to characterize the humoral response and its effects on signal transduction in relation with the clinical outcome. Eighty NSCLC patients treated with first-line chemotherapy were randomized to receive the EGF vaccine or supportive care. EGF concentration in sera, anti-EGF antibodies and their capacity to inhibit the binding between EGF/EGF receptor (EGFR), and the EGFR phosphorylation were measured. Seventy-three percent of vaccinated patients developed a good antibody response, whereas none of the controls did. In good antibody-responder patients, self EGF in sera was significantly reduced. In 58% of vaccinated patients, the post-immune sera inhibited EGF/EGFR binding; in the control group, no inhibition occurred. Post-immune sera inhibited the EGFR phosphorylation whereas sera from control patients did not have this capacity. Good antibody-responder patients younger than 60 years had a significantly better survival. A high correlation between anti-EGF antibody titers, EGFR phosphorylation inhibition, and EGF/EGFR binding inhibition was found. There was a significantly better survival for vaccinated patients that showed the higher capacity to inhibit EGF/EGFR binding and for those who showed an immunodominance by the central region of EGF molecule. Immunization with the EGF vaccine induced neutralizing anti-EGF antibodies capable of inhibiting EGFR phosphorylation. There was a significant positive correlation between antibody titers, EGF/EGFR binding inhibition, immunodominance of anti-EGF antibodies, and survival in advanced NSCLC patients.

Sensitivity and Specificity of Fluorescent Immunoguided Neoplasm Detection in Head and Neck Cancer Xenografts

To determine whether fluorescently labeled anti-epidermal growth factor (EGFR) antibody could be used to detect residual disease and to guide surgical resections by comparing the sensitivity and specificity of optical fluorescence imaging with the sensitivity and specificity of histopathologic evaluation. A preclinical model of head and neck squamous cell carcinoma. Mice xenografted with SCC-1 tumor cells. The mice underwent systemic injection with anti-EGFR antibody (cetuximab) conjugated to an optically active fluorophore (Cy5.5). Both a subcutaneous flank model (n = 18) and an orthotopic murine model (n = 15) were used to assess for the presence of residual disease by fluorescent stereomicroscopy after subtotal resections of tumors. Histologic analysis was performed to confirm the presence or absence of disease. In the subcutaneous flank model, a diagnostic dose (50 microg) and therapeutic dose (250 microg) of fluorescent-labeled anti-EGFR were administered. When a diagnostic dose was given, the sensitivity was 86%, which was less than the 91% sensitivity when the higher dose was given. Tumor biopsy specimens in which disease was detected by histologic analysis but not by fluorescence (false-negative result) averaged 166 cells (range, 50-350 cells). The specificity of optical fluorescence to predict the presence of tumor in both groups was 100%. In the floor of the mouth model, we demonstrated a sensitivity of 81% and a specificity of 100%. False-negative results were obtained in a tumor fragment measuring less than 0.5 mm in diameter. These data support further investigation of fluorescently labeled anti-EGFR antibody to detect disease in the surgical setting.