Epidermal growth factor-based cancer vaccine for non-small-cell lung cancer therapy

Immunotherapeutics in lung cancers: from mechanistic insight to clinical implications and synergistic perspectives

BACKGROUND

Lung cancer is one of the highly lethal forms of cancer whose incidence has worldwide rapidly increased over the past few decades. About 80-85% of all lung cancer cases constitute non-small cell lung cancer (NSCLC), with adenocarcinoma, squamous cell carcinoma and large cell carcinoma as the main subtypes. Immune checkpoint inhibitors have led to significant advances in the treatment of a variety of solid tumors, significantly improving cancer patient survival rates.

METHODS AND RESULTS

The cytotoxic drugs in combination with anti-PD-(L)1 antibodies is a new method that aims to reduce the activation of immunosuppressive and cancer cell prosurvival responses while also improving direct cancer cell death. The most commonly utilized immune checkpoint inhibitors for patients with non-small cell lung cancer are monoclonal antibodies (Atezolizumab, Cemiplimab, Ipilimumab, Pembrolizumab etc.) against PD-1, PD-L1, and CTLA-4. Among them, Atezolizumab (TECENTRIQ) and Cemiplimab (Libtayo) are engineered monoclonal anti programmed death ligand 1 (PD-L1) antibodies that inhibit binding of PD-L1 to PD-1 and B7.1. As a result, T-cell proliferation and cytokine synthesis are inhibited leading to restoring the immune homeostasis to fight cancer cells.

CONCLUSIONS

In this review article, the path leading to the introduction of immunotherapeutic options in lung cancer treatment is described, with analyzing the benefits and shortages of the current immunotherapeutic drugs. In addition, possibilities to co-administer immunotherapeutic agents with standard cancer treatment modalities are also considered.

Current progress in the development of prophylactic and therapeutic vaccines

Vaccines are essential public health tools and play an important role in reducing the burden of infectious diseases in the population. Emerging infectious diseases and outbreaks pose new challenges for vaccine development, requiring the rapid design and production of safe and effective vaccines against diseases with limited resources. Here, we focus on the development of vaccines in broad fields ranging from conventional prophylactic vaccines against infectious diseases to therapeutic vaccines against chronic diseases and cancer providing a comprehensive overview of recent advances in eight different vaccine forms (live attenuated vaccines, inactivated vaccines, polysaccharide and polysaccharide conjugate vaccines, recombinant subunit vaccines, virus-like particle and nanoparticle vaccines, polypeptide vaccines, DNA vaccines, and mRNA vaccines) and the therapeutic vaccines against five solid tumors (lung cancer breast cancer colorectal cancer liver cancer and gastric cancer), three infectious diseases (human immunodeficiency virus, hepatitis B virus and human papillomavirus-induced diseases) and three common chronic diseases (hypertension, diabetes mellitus and dyslipidemia). We aim to provide new insights into vaccine technologies, platforms, applications and understanding of potential next-generation preventive and therapeutic vaccine technologies paving the way for the vaccines design in the future.

Advances in the Lung Cancer Immunotherapy Approaches

Despite the progress in the comprehension of LC progression, risk, immunologic control, and treatment choices, it is still the primary cause of cancer-related death. LC cells possess a very low and heterogeneous antigenicity, which allows them to passively evade the anticancer defense of the immune system by educating cytotoxic lymphocytes (CTLs), tumor-infiltrating lymphocytes (TILs), regulatory T cells (Treg), immune checkpoint inhibitors (ICIs), and myeloid-derived suppressor cells (MDSCs). Though ICIs are an important candidate in first-line therapy, consolidation therapy, adjuvant therapy, and other combination therapies involving traditional therapies, the need for new predictive immunotherapy biomarkers remains. Furthermore, ICI-induced resistance after an initial response makes it vital to seek and exploit new targets to benefit greatly from immunotherapy. As ICIs, tumor mutation burden (TMB), and microsatellite instability (MSI) are not ideal LC predictive markers, a multi-parameter analysis of the immune system considering tumor, stroma, and beyond can be the future-oriented predictive marker. The optimal patient selection with a proper adjuvant agent in immunotherapy approaches needs to be still revised. Here, we summarize advances in LC immunotherapy approaches with their clinical and preclinical trials considering cancer models and vaccines and the potential of employing immunology to predict immunotherapy effectiveness in cancer patients and address the viewpoints on future directions. We conclude that the field of lung cancer therapeutics can benefit from the use of combination strategies but with comprehension of their limitations and improvements.

Augmenting antibody response to EGF-depleting immunotherapy: Findings from a phase I trial of CIMAvax-EGF in combination with nivolumab in advanced stage NSCLC

Background

CIMAvax-EGF is an epidermal growth factor (EGF)-depleting immunotherapy which has shown survival benefit as a switch maintenance treatment after platinum-based chemotherapy in advanced non-small cell lung cancer (NSCLC). The primary objective of this trial is to establish the safety and recommended phase II dose (RP2D) of CIMAvax-EGF in combination with nivolumab as second-line therapy for NSCLC.

Methods

Patients with immune checkpoint inhibitor-naive metastatic NSCLC were enrolled using a “3+3” dose-escalation design. Toxicities were graded according to CTCAE V4.03. Thirteen patients (one unevaluable), the majority with PD-L1 0%, were enrolled into two dose levels of CIMAvax-EGF.

Findings

The combination was determined to be safe and tolerable. The recommended phase 2 dose of CIMAvax-EGF was 2.4 mg. Humoral response to CIMAvax-EGF was achieved earlier and in a greater number of patients with the combination compared to historical control. Four out of 12 evaluable patients had an objective response.

A Novel Combined Conjugate Therapeutic Cancer Vaccine, Recombinant EGF-CRM197, in Patients With Advanced Solid Tumors: A Phase I Clinical Study

Introduction

The therapeutic cancer vaccine recombinant Epidermal Growth Factor (EGF)-CRM197 is a novel combined conjugate EGF with CRM197 as a carrier protein. Immunization with the EGF-CRM197 vaccine can induce high levels of neutralizing anti-EGF antibodies that inhibit EGF/EGFR signaling and thereby suppress growth of tumors that rely on this signaling pathway. Herein, we characterize the humoral immune responses elicited by the recombinant EGF-CRM197 vaccine in patients with advanced solid tumors in a phase I clinical trial and assess the safety, tolerability, and immunogenicity of this vaccine (CTR20190473).

Methods

A total of 16 subjects were enrolled in this study. Under 6 + 3 design, patients in each dosing cohort were administrated subcutaneously at a dosage of 0.4 mg, 0.8 mg, and 1.6 mg, respectively. The patients received vaccinations for immune induction (once a week for 4 consecutive weeks) and booster vaccinations (once every 4 weeks). Safety evaluation was performed 1 week after the immune induction. Booster vaccination was given until the occurrence of disease progression, intolerance, withdrawal of informed consent by the patient, or negative result of anti-EGF test after two booster vaccinations.

Results

Vaccination with EGF-CRM197 is safe and well-tolerated in patients with advanced solid tumors. Adverse reactions at the injection site were the most common adverse events (AEs) in recipients. No severe adverse reactions post vaccination were observed in the present study. Vaccinated patients developed a robust neutralizing antibody response triggered by EGF-CRM197 that significantly reduced the levels of EGF in serum. For lung cancer patients who were super good antibody responders (sGAR) to EGF-CRM197, the median progress-free survival (PFS) was 4.83 months, significantly longer than that of the good antibody responder (GAR) patients with lung cancer whose median PFS was 2.10 months (P=0.0018). The median overall survival (OS) of GAR lung cancer patients was 10.67 months while the OS) for sGAR lung cancer patients was not reached until analysis was performed. The median follow-up of the sGAR lung cancer patients was 14.6 months.

Conclusion

Our study demonstrates that the recombinant EGF-CRM197 therapeutic cancer vaccine can induce a good immune response in patients with advanced solid tumors and is safe and well tolerated, which ensures further clinical development of the vaccine for extending the survival time of EGF-CRM197 sensitive patients with advanced solid tumors.

Clinical Trial Registration

http://www.chinadrugtrials.org.cn, identifier CTR20190473, EGF-CRM197.

Inhalable polymeric micro and nano-immunoadjuvants for developing therapeutic vaccines in the treatment of non-small cell lung cancer

Non-small cell lung cancer (NSCLC) is a leading cause of death in millions of cancer patients. Lack of diagnosis at an early stage in addition to no specific guidelines for its treatment, and a higher rate of treatment-related toxicity further deteriorate the conditions. Current therapies encompass surgery, chemotherapy, radiation therapy, and immunotherapy according to the pattern and the stage of lung cancer. Among all, with a longlasting therapeutic action, reduced side-effects, and a higher rate of survival, therapeutic cancer vaccine is a new, improved strategy for treating NSCLC. Immunoadjuvants are usually incorporated into the therapeutic vaccines to shield the antigen against environmental and physiological harsh conditions in addition to boosting the immune potential. Conventional immunoadjuvants are often associated with an inadequate cellular response, poor target specificity, and low antigen load. Recently, inhalable polymeric nano/micro immunoadjuvants have exhibited immense potential in the development of therapeutic vaccines for the treatment of NSCLC with improved mucosal immunization. The development of polymeric micro/nano immunoadjuvants brought a new era for vaccines with increased strength and efficiency. Therefore, in the present review, we explained the potential application of micro/nano immunoadjuvants for augmenting the stability and efficacy of inhalable vaccines in the treatment of NSCLC. In addition, the role of biodegradable, biocompatible, and non-toxic polymers has also been discussed with case studies.

Immunotherapy for non-small cell lung cancer (NSCLC), as a stand-alone and in combination therapy

Non-small cell lung cancer (NSCLC) is of major concern for society as it is associated with high mortality and is one of the most commonly occurring of all cancers. Due to the number of mutational variants and general heterogeneity of this type of cancer, treatment using conventional modalities has been challenging. Therefore, it is important to have improved therapeutic treatments like immunotherapy, that can specifically treat the disease while causing minimal damage to healthy tissue and additionally provide systemic immunity. Cancer vaccines are an important element of cancer immunotherapy and have been approved for treatment of a limited number of cancers, including NSCLC. This article highlights scientific evidence for several therapeutic treatment strategies for NSCLC, alone or in combination, which offers new hope for those suffering. Although cancer vaccines have had some success as a monotherapy, their potential in a combination therapy needs to be critically analyzed for future applications.

Immunotherapy for ALK-Rearranged Non-Small Cell Lung Cancer: Challenges Inform Promising Approaches

Rearrangements in the Anaplastic Lymphoma Kinase (ALK) gene have been implicated in 5-6% of all non-small cell lung cancers. ALK-rearranged non-small cell lung cancers are sensitive to ALK-directed tyrosine kinase inhibitors, but generally resistant to single-agent immune checkpoint inhibitors. Here, we aim to describe the mechanisms of ALK aberrations in non-small cell lung cancer by which an immunosuppressed tumor microenvironment is created, leading to host immune evasion. We report pre-clinical and clinical studies evaluating novel immunotherapeutic approaches and describe the promises and challenges of incorporating immune-based treatments for ALK-rearranged non-small cell lung cancer.

Identifying predictive biomarkers of CIMAvaxEGF success in non-small cell lung cancer patients

BACKGROUND

Immunosenescence biomarkers and peripheral blood parameters are evaluated separately as possible predictive markers of immunotherapy. Here, we illustrate the use of a causal inference model to identify predictive biomarkers of CIMAvaxEGF success in the treatment of Non-Small Cell Lung Cancer Patients.

METHODS

Data from a controlled clinical trial evaluating the effect of CIMAvax-EGF were analyzed retrospectively, following a causal inference approach. Pre-treatment potential predictive biomarkers included basal serum EGF concentration, peripheral blood parameters and immunosenescence biomarkers. The proportion of CD8 + CD28- T cells, CD4+ and CD8+ T cells, CD4/CD8 ratio and CD19+ B cells. The 33 patients with complete information were included. The predictive causal information (PCI) was calculated for all possible models. The model with a minimum number of predictors, but with high prediction accuracy (PCI > 0.7) was selected. Good, rare and poor responder patients were identified using the predictive probability of treatment success.

RESULTS

The mean of PCI increased from 0.486, when only one predictor is considered, to 0.98 using the multivariate approach with all predictors. The model considering the proportion of CD4+ T cell, basal Epidermal Growth Factor (EGF) concentration, neutrophil to lymphocyte ratio, Monocytes, and Neutrophils as predictors were selected (PCI > 0.74). Patients predicted as good responders according to the pre-treatment biomarkers values treated with CIMAvax-EGF had a significant higher observed survival compared with the control group (p = 0.03). No difference was observed for bad responders.

CONCLUSIONS

Peripheral blood parameters and immunosenescence biomarkers together with basal EGF concentration in serum resulted in good predictors of the CIMAvax-EGF success in advanced NSCLC. Future research should explore molecular and genetic profile as biomarkers for CIMAvax-EGF and it combination with immune-checkpoint inhibitors. The study illustrates the application of a new methodology, based on causal inference, to evaluate multivariate pre-treatment predictors. The multivariate approach allows realistic predictions of the clinical benefit of patients and should be introduced in daily clinical practice.

Anti-EGF antibodies as surrogate biomarkers of clinical efficacy in stage IIIB/IV non-small-cell lung cancer patients treated with an optimized CIMAvax-EGF vaccination schedule

We previously reported that CIMAvax-EGF vaccine is safe, immunogenic and efficacious to treat advanced non-small-cell lung cancer (NSCLC) patients. A phase III trial was designed using an optimized immunization schedule. It included higher antigen dose and injections at multiple sites. Immune response and circulating biomarkers were studied in a subset of patients. EGF-specific antibody titers, IgG subclasses, peptide immunodominance and circulating biomarkers were assessed by ELISA. In vitro EGF-neutralization capacity of immune sera and EGF-IgG binding kinetics was evaluated by Western Blot and Surface Plasmon Resonance (SPR) technology, respectively. We show that CIMAvax-EGF elicited mainly IgG3/IgG4 antibodies at titers exceeding 1:4000 in 80% of vaccinated patients after 3 months of treatment. The EGF-specific humoral response was directed against the central region of the EGF molecule. For the first time, the kinetic constants of EGF-specific antibodies were measured evidencing affinity maturation of antibody repertoire up to month 12 of vaccination. Notably, the capacity of post-immune sera to inhibit EGFR phosphorylation significantly increased during the course of the immunization scheme and was related to clinical outcome (P = .013, log-rank test). Basal concentrations of EGF and TGFα in the serum were affected by EGF-based immunization. In conclusion, the CIMAvax-EGF vaccine induces an EGF-specific protective humoral response in a high percent of NSCLC vaccinated patients, the quantity and quality of which were associated with clinical benefit (clinical trial registration number: RPCEC00000161, http://registroclinico.sld.cu/).

Abbreviations

EGF: epidermal growth factor; EGFR: epidermal growth factor receptor; Ab: antibody; AR: amphiregulin; NSCLC: non-small-cell lung cancer; rhEGF: recombinant human epidermal growth factor; BSC: best supportive care; TGFα: tumor growth factor alpha; IL-8: interleukin 8; MAb: monoclonal antibody; SPR: surface plasmon resonance

Biological therapies in lung cancer treatment: using our immune system as an ally to defeat the malignancy

INTRODUCTION

Biological therapies, with immunotherapy leading the field, have arisen as one of the quickest expanding areas of research for cancer treatment in the last few years. The clear benefits for patients are undeniable, satisfying the long-awaited necessity of a target-specific therapy. However, its full potential remains still unexploited due to a lack of response in a majority of patients and pending reliable biomarkers.

AREAS COVERED

This review provides a summarizing view of the current biological therapies for lung cancer, focusing on immunotherapy - including immune checkpoint inhibitors, adoptive cell therapy and vaccines available in clinical/pre-clinical settings or currently in development. A thorough analysis of the technical and functional differences among all therapies is provided, along with a critical discussion of prospective treatments and potential biomarkers.

EXPERT OPINION

The use of immunotherapy in the treatment of cancer has provided clear benefits for patients. Still, exploitation of the full potential of immune checkpoint inhibitors alone or in combination, or adoptive cell therapies is hampered by, amongst other reasons, the lack of reliable biomarkers and possible adverse immune effects. We postulate that the development of liquid biopsy-based diagnostics will help to overcome these limitations in the near future.

CIMAvax-EGF, a therapeutic non-small cell lung cancer vaccine

INTRODUCTION

Lung cancer represents the most common cause of cancer death worldwide. While the prognosis remains poor, immunotherapy is giving a positive impact on survival. Cancer vaccines represent a form of active immunotherapy that historically has given modest results in terms of efficacy. The overexpression of the EGFR by tumor cells was reported in more than half of cases of lung cancer, representing a mechanism of cancerogenesis. CIMAvax-EGF, a therapeutic vaccine for non-small cell lung cancer (NSCLC) developed in Cuba, consists of a human recombinant EGF able to induce antibodies against the autologous EGF, resulting in serum EGF withdrawal and lower EGF-EGFR interaction. Area covered: We critically reviewed the existing literature about CIMAvax-EGF, from the Pilot studies to the efficacy controlled studies. We also overviewed the ongoing trials. Expert opinion: CIMAvax-EGF demonstrated to be safe and immunogenic. In a phase III randomized study CIMAvax-EGF, used as a switch maintenance treatment after platinum-based chemotherapy, did not significantly improve survival. Current data are not sufficient to recommend CIMAvax-EGF as a treatment option for advanced stage NSCLC. Further studies, conducted in a context of worldwide standardized clinical practice, are needed to better define if a subpopulation of patients can benefit from the vaccination.

CIMAvax-EGF: Toward long-term survival of advanced NSCLC

Lung cancer remains one of the leading causes of cancer-related deaths. Non-small cell lung cancer (NSCLC) is the most common histologic type of lung cancer. Medical and scientific progress has led to longer survival in an increasing number of patients suffering from cancer. Concerning patients with advanced NSCLC, there is a subgroup with long-term survival. The human epidermal growth factor receptor (EGFR) family plays a key role in tumor development. This cluster of genes is associated with augmented angiogenesis and enhanced proliferation, survival, and migration of tumor cells. The CIMAvax-EGF vaccine consists of a chemical conjugate of the EGF with the P64 protein derived from the Meningitis B bacteria and the Montanide ISA 51, as adjuvant. The vaccine induces antibodies against EGF that results in EGF withdrawal. CIMAvax-EGF has been demonstrated to be safe and immunogenic in advanced NSCLC patients. Here we summarize the current knowledge of the mechanism of action of CIMAvax-EGF, highlighting the impact of this anti-EGF-based vaccine on the long-term survival of advanced NSCLC patients.

Vaccine and immune cell therapy in non-small cell lung cancer

Despite new advances in therapeutics, lung cancer remains the first cause of mortality among different types of malignancies. To improve survival, different strategies have been developed such as chemotherapy combinations, targeted therapies and more recently immunotherapy. Immunotherapy is based on the capability of the immune system to differentiate cancer cells from normal cells to fight against the tumor. The two main checkpoint inhibitors that have been widely studied in non-small cell lung cancer (NSCLC) are PD-1/PD-L1 and CTLA-4. However, interactions between tumor and immune system are much more complex with several different elements that take part and probably many new interactions to be discovered and studied for a better comprehension of those pathways. Vaccines are part of the prophylaxis and of the treatment for different infectious diseases. For that reason, they have allowed us to improve global survival worldwide. This same idea can be used for cancer treatment. First reports in clinical trials that used therapeutic vaccines in NSCLC were discouraging, but currently vaccines have a new chance in cancer therapy with the identification of new targetable antigens, adjuvant treatments and most interestingly, the combination of vaccines with anti-PD-1/PD-L1 and anti-CTLA-4 drugs. The aim of this article is to describe the scientific evidence that has been reported for the different types of vaccines and their mechanisms of action in the fight against NSCLC tumors to improve disease control.

Therapeutic cancer vaccine: phase I clinical tolerance study of Hu-rhEGF-rP64k/Mont in patients with newly diagnosed advanced non-small cell lung cancer

Background

Hu-rhEGF-rP64k/Mont is a biotechnology product for the treatment of advanced non-small cell lung cancer (NSCLC). The vaccine induces a neutralizing antibody-mediated immune response, against the normal circulating self-protein antigen epidermal growth factor (EGF), which prevents its binding to and activation of the EGF receptor, inhibiting the transduction of the signals that drive cancer cell proliferation, survival and spread. This phase I study aimed to evaluate the safety and the immunological response of Hu-rhEGF-rP64k vaccine in NSCLC patients.

Results

The Hu-rhEGF-rP64k/Mont vaccine showed to be safe and well tolerated, with dizziness, injection-site reactions and tremors being the most commonly reported adverse event. No severe adverse events or death were related to the vaccination. Immune monitoring demonstrated the generation of anti-EGF antibody titers and as a consequence the patients exhibited a decrease in the EGF concentration. In 80% of the vaccinated patients stable disease was achieved.

Conclusion

Hu-rhEGF-rP64k/Mont elicited a valuable immune response, with good safety profile assuring further clinical development of the vaccine in this population to further confirm the potential benefits on survival.

Trial registration

Chinese Clinical Trial Registry, ChiCTR-OID-17014048, date 2017/12/20 (retrospectively registered); Chinese Food and Drug Administration, CFDA 2009 L02105, date 2009/04/03; China Drug Trial, CTR20131039.

Immunotherapeutic strategies in non-small-cell lung cancer: the present and the future

Non-small cell lung cancer (NSCLC) is still the leading cause of cancer death worldwide, with a poor prognosis. In the era of immunotherapies, the field is rapidly changing, and the clinician needs to be aware of the current state and future perspectives of immunotherapeutic strategies. In this review, we discuss the current status of immune checkpoint inhibitors, cancer vaccines and cellular therapies specifically in NSCLC. Last but not least, we will discuss rational combination strategies that are promising for the near future.

An enzyme immunoassay for determining epidermal growth factor (EGF) in human serum samples using an ultramicroanalytical system

Human epidermal growth factor is a small peptide consisting of 53 amino acid residues, which stimulates cell proliferation and is associated with several human carcinomas. A simple sandwich-type ultramicroELISA assay (UMELISA), based on the advantages of high affinity reaction between streptavidin and biotin has been developed for the measurement of EGF in human serum samples. Strips coated with a high affinity monoclonal antibody directed against EGF are used as solid phase, to ensure the specificity of the assay. The EGF assay was completed in 18 hr, with a measuring range of 39-2500 pg/mL. The intra- and inter-assay coefficients of variation were 4.4-7.3% and 0-5.1%, respectively, depending on the EGF concentrations evaluated. Percentage recovery ranged from 96-104%. Regression analysis showed a good correlation with the commercially available Human EGF Immunoassay Quantikine^® ELISA kit (n = 130, r = 0.92, P < 0.01). The analytical performance characteristics of our UMELISA EGF endorse its use for the quantification of EGF in human serum samples.

Pathway Targeted Immunotherapy: Rationale and Evidence of Durable Clinical Responses with a Novel, EGF-directed Agent for Advanced NSCLC

Abnormalities in the epidermal growth factor (EGF) and EGFR pathway promote progression of NSCLC. Immunization with EGF vaccine induces specific, neutralizing anti-EGF antibodies that prevent binding of the ligand to its receptor. This concept of pathway targeted immunotherapy (PTI) was validated in vitro by dose-related suppression of EGFR, Akt, and Erk1/2 phosphorylation in cell lines with different mutations. A randomized phase II trial showed improved overall survival (OS) in subgroups with advanced NSCLC showing a clear immunologic response. By per-protocol analysis of the ensuing phase IIb trial, patients receiving EGF PTI survived 3 months longer than controls (12.43 versus 9.43 months; hazard ratio = 0.77 [95% confidence interval, 0.61-0.98]). These data were confirmed in a larger trial showing an OS benefit over control of >3 months. The variable most strongly correlated with efficacy was circulating EGF at enrolment. Patients with serum EGF levels >250 pg/mL benefited most from treatment with EGF PTI. Of 188 patients tested, 94 were above this biomarker threshold. The OS benefit from active versus control treatment was 6.7 months. More than 15% of patients had responses for >5 years. Long-term survivors are seen in all EGF PTI trials. Treatment is well-tolerated, induces high anti-EGF antibody titers, reduces levels of circulating serum EGF, achieves durable responses, and significantly prolongs OS. A threshold of 250 pg/mL has been set to enrich the study population in the ongoing pivotal trial. This biomarker-guided study in an enriched population of patients with both squamous and nonsquamous stage IV NSCLC aims to replicate the favorable efficacy/tolerability balance of earlier studies.

Non-small cell lung cancer: current treatment and future advances

Lung cancer has a poor prognosis; over half of people diagnosed with lung cancer die within one year of diagnosis and the 5-year survival is less than 18%. Non-small cell lung cancer (NSCLC) accounts for the majority of all lung cancer cases. Risk factors for developing NSCLC have been identified, with cigarette smoking being a major factor along with other environmental and genetic risk factors. Depending on the staging of lung cancer, patients are eligible for certain treatments ranging from surgery to radiation to chemotherapy as well as targeted therapy. With the advancement of genetics and biomarkers testing, specific mutations have been identified to better target treatment for individual patients. This review discusses current treatments including surgery, chemotherapy, radiotherapy, and immunotherapy as well as how biomarker testing has helped improve survival in patients with NSCLC.

Immunotherapy Comes of Age in Lung Cancer

Lung carcinoma is the leading cause of death by cancer worldwide. When possible, surgery is the best treatment strategy for patients with non-small-cell lung cancer. However, even with curative-intent therapy, most patients will develop local or systemic recurrence and, ultimately, succumb to their disease. In recent years, evidence on the role of the antitumor activity of the immune system and the understanding of tumor immunosurveillance have resulted in the emergence of immunotherapy as a promising therapeutic approach in lung cancer. The main approaches are immune checkpoint inhibition, such as blockade of the cytotoxic T-lymphocyte antigen-4 and programmed cell death-1 receptors and the programmed cell death-1 ligand, and vaccine therapy, which elicits specific antitumor immunity against relevant tumor-associated antigens. We have reviewed recently reported results from clinical trials and the possible future role of vaccine therapy and immune checkpoint inhibition in the treatment of small cell lung cancer and non-small-cell lung cancer.

Non-small cell lung cancer: current treatment and future advances

Lung cancer has a poor prognosis; over half of people diagnosed with lung cancer die within one year of diagnosis and the 5-year survival is less than 18%. Non-small cell lung cancer (NSCLC) accounts for the majority of all lung cancer cases. Risk factors for developing NSCLC have been identified, with cigarette smoking being a major factor along with other environmental and genetic risk factors. Depending on the staging of lung cancer, patients are eligible for certain treatments ranging from surgery to radiation to chemotherapy as well as targeted therapy. With the advancement of genetics and biomarkers testing, specific mutations have been identified to better target treatment for individual patients. This review discusses current treatments including surgery, chemotherapy, radiotherapy, and immunotherapy as well as how biomarker testing has helped improve survival in patients with NSCLC.

Emerging therapeutic targets in metastatic progression: A focus on breast cancer

Metastasis is the underlying cause of death for the majority of breast cancer patients. Despite significant advances in recent years in basic research and clinical development, therapies that specifically target metastatic breast cancer remain inadequate, and represents the single greatest obstacle to reducing mortality of late-stage breast cancer. Recent efforts have leveraged genomic analysis of breast cancer and molecular dissection of tumor-stromal cross-talk to uncover a number of promising candidates for targeted treatment of metastatic breast cancer. Rational combinations of therapeutic agents targeting tumor-intrinsic properties and microenvironmental components provide a promising strategy to develop precision treatments with higher specificity and less toxicity. In this review, we discuss the emerging therapeutic targets in breast cancer metastasis, from tumor-intrinsic pathways to those that involve the host tissue components, including the immune system.

A Phase III Clinical Trial of the Epidermal Growth Factor Vaccine CIMAvax-EGF as Switch Maintenance Therapy in Advanced Non-Small Cell Lung Cancer Patients

PURPOSE

EGFR is a well-validated target for patients with non-small cell lung cancer (NSCLC). CIMAvax-EGF is a therapeutic cancer vaccine composed of human recombinant EGF conjugated to a carrier protein and Montanide ISA51 as adjuvant. The vaccine is intended to induce antibodies against self EGFs that block EGF-EGFR interaction.

EXPERIMENTAL DESIGN

To evaluate overall survival, safety, immunogenicity, and EGF concentration in serum after CIMAvax-EGF, a randomized phase III trial was done in patients with advanced NSCLC. Four to 6 weeks after first-line chemotherapy, 405 patients with stage IIIB/IV NSCLC were randomly assigned to a vaccine group, which received CIMAvax-EGF or a control group, treated with best supportive care.

RESULTS

Long-term vaccination was very safe. Most frequent adverse reactions were grade 1 or 2 injection-site pain, fever, vomiting, and headache. Vaccination induced anti-EGF antibodies and decreased serum EGF concentration. In the safety population, median survival time (MST) was 10.83 months in the vaccine arm versus 8.86 months in the control arm. These differences were not significant according the standard log rank (HR, 0.82; P = 0.100), but according a weighted log rank (P = 0.04) that was applied once the nonproportionality of the HR was verified. Survival benefit was significant (HR, 0.77; P = 0.036) in the per-protocol setting (patients receiving at least four vaccine doses): MST was 12.43 months for the vaccine arm versus 9.43 months for the control arm. MST was higher (14.66 months) for vaccinated patients with high EGF concentration at baseline.

CONCLUSIONS

Switch maintenance with CIMAvax-EGF was well tolerated and significantly increased MST of patients that completed induction vaccination. Baseline EGF concentration predicted survival benefit. Clin Cancer Res; 22(15); 3782-90. ©2016 AACR.

CIMAvax EGF (EGF-P64K) vaccine for the treatment of non-small-cell lung cancer

Epidermal growth factor receptor (EGFR) is overexpressed in many epithelial tumors and its role in the development of non-small-cell lung cancer (NSCLC) is widely documented. CIMAvax-EGF is a therapeutic cancer vaccine composed by recombinant EGF conjugated to a carrier protein and emulsified in Montanide ISA51. Vaccination induces antibodies against self-EGF that block EGF-EGFR interaction and inhibit EGFR phosphorylation. Five clinical trials were conducted to optimize vaccine formulation and schedule. Then, two randomized studies were completed in advanced NSCLC, where CIMAvax-EGF was administered after chemotherapy, as 'switch maintenance'. The vaccine was very well tolerated and the most frequent adverse events consisted of grade 1/2 injection site reactions, fever, headache, vomiting and chills. CIMAvax was immunogenic and EGF concentration was reduced after vaccination. Subjects receiving a minimum of 4 vaccine doses had a significant survival advantage. NSCLC patients with high EGF concentration at baseline had the largest benefit, comparable with best maintenance therapies.

A phase II trial evaluating the clinical and immunologic response of HLA-A2(+) non-small cell lung cancer patients vaccinated with an hTERT cryptic peptide

OBJECTIVES

The immunological and clinical responses of patients with NSCLC treated, in the context of an expanded action program, with the cryptic hTERT-targeting Vx-001 vaccine are presented.

MATERIALS AND METHODS

Forty-six HLA-A*0201-positive patients with advanced NSCLC and residual (n=27) or progressive (n=19) disease following front-line treatment received two subcutaneous injections of the optimized TERT572Y peptide followed by four injections of the native TERT572 peptide, every 3 weeks. Peptide-specific immune responses were monitored by enzyme-linked immunosorbent spot assay at baseline, and after the 2nd and the 6th vaccinations. Thirty-eight HLA-A*0201-positive matched patients were used as historical controls.

RESULTS

Twenty-three patients (50%) completed the vaccination protocol and 87% received at least two administrations. Twelve patients (26%) without disease progression after the 6th vaccination received boost vaccinations. Three (7%) patients achieved a partial response and 13 (28%) disease stabilization. The disease control rate was significantly higher in patients with non-squamous histology compared to those with squamous-cell histology [n=14 (45%) versus n=2 (13%); p=0.03]. The median progression-free survival (PFS) and overall survival (OS) was 3.8 (range, 0.7-99.4) and 19.8 months (range, 0.7-99.4), respectively. Patients who developed immune response had a numerically higher PFS compared to those who failed to mount any (6.7 versus 2.7 months; p=0.090). However, the median OS for the immune-responders was significantly prolonged compared to non-responders (40.0 versus 9.2 months, respectively; p=0.02). Toxicity was <grade 2.

CONCLUSION

Vx-001 vaccine is well tolerated and induced a TERT-specific immunological response, which was significantly correlated with improved clinical outcome.

Clinical trials targeting lung cancer with active immunotherapy: the scope of vaccines

Successful active immunotherapy is expected to be specific and nontoxic. Until now, the success of immunotherapy in cancer has been sporadic and unpredictable. This has been attributable in part to the lack of a full understanding of the mechanistic underpinnings of immune regulation. Furthermore, the lack of systematic success of immunotherapy, as argued in this review, stems from failing to effectively target tumors such as non-small cell lung cancer. In this review, the rationale and design for induction of immunity to non-small cell lung cancer and clinical trials of the most important lung cancer vaccines in development are discussed.

New Approaches in Immunotherapy for the Treatment of Lung Cancer

Despite the several advances in the last few years into treatment of advanced lung cancer, the 5-year survival remains extremely low. New therapeutic strategies are currently under investigation, and immunotherapy seems to offer a promising treatment alternative. In the last decade, therapeutic cancer vaccines in lung cancer have been rather disappointing, mainly due to the lack of efficient predictive biomarkers. A better refinement of the patient population that might respond to treatment might finally lead to a success story. For the first time, the immune checkpoint inhibitors are demonstrating sustained antitumor response and improved survival and they may be the first immunotherapeutics available for patients with lung cancer.

Attenuation of CCl4-induced hepatic fibrosis in mice by vaccinating against TGF-β1

Transforming growth factor β1 (TGF-β1) is the pivotal pro-fibrogenic cytokine in hepatic fibrosis. Reducing the over-produced expression of TGF-β1 or blocking its signaling pathways is considered to be a promising therapeutic strategy for hepatic fibrosis. In this study, we evaluated the feasibility of attenuating hepatic fibrosis by vaccination against TGF-β1 with TGF-β1 kinoids. Two TGF-β1 kinoid vaccines were prepared by cross-linking TGF-β1-derived polypeptides (TGF-β1(25)-[41-65] and TGF-β1(30)-[83-112]) to keyhole limpet hemocyanin (KLH). Immunization with the two TGF-β1 kinoids efficiently elicited the production of high-levels of TGF-β1-specific antibodies against in BALB/c mice as tested by enzyme-linked immunosorbent assay (ELISA) and Western blotting. The antisera neutralized TGF-β1-induced growth-inhibition on mink lung epithelial cells (Mv1Lu) and attenuated TGF-β1-induced Smad2/3 phosphorylation, α-SMA, collagen type 1 alpha 2 (COL1A2), plasminogen activator inhibitor-1 (PAI-1) and tissue inhibitor of metalloproteinase-1 (TIMP-1) expression in the rat hepatic stellate cell (HSC) line, HSC-T6. Vaccination against TGF-β1 with the kinoids significantly suppressed CCl4-induced collagen deposition and the expression of α-SMA and desmin, attenuated hepatocyte apoptosis and accelerated hepatocyte proliferation in BALB/c mice. These results demonstrated that immunization with the TGF-β1 kinoids efficiently attenuated CCl4-induced hepatic fibrosis and liver injury. Our study suggests that vaccination against TGF-β1 might be developed into a feasible therapeutic approach for the treatment of chronic fibrotic liver diseases.

Effect of blockade of the EGF system on wound healing in patients vaccinated with CIMAvax® EGF

Background

The epidermal growth factor receptor (EGFR) signaling system is frequently unbalanced in human malignancies due to increased ligand production, receptor overexpression, receptor mutations, and/or cross-talk with other receptor systems. For this reason, the EGFR is an attractive target for anticancer therapy. The epidermal growth factor also plays an important role in regulating multiple facets of cutaneous wound healing, including inflammation, wound contraction, proliferation, migration, and angiogenesis. In the Center of Molecular Immunology, a cancer vaccine is produced (CIMAvax® EGF) that blocks the binding of EGF to its receptor. This blockade causes a significant inverse association between the anti-EGF antibody titers and EGF concentration. Around 1,500 patients with non-small cell lung cancer have been treated, showing that this vaccine is safe, immunogenic, increases survival and improves quality of life. Taking into account the therapeutic benefits of CIMAvax® EGF vaccination and the role of EGF-EGFR system in the wound healing process, we decided to conduct a retrospective research with the aim of determining the effect to the CIMAvax® EGF vaccine on the wound healing process in patients undergoing surgical treatment.

Methods

Medical records of 452 vaccinated patients were reviewed and only six patients receiving surgical treatment were identified. Further information about these six patients was obtained from source documents, including medical records and operative reports using an observational list that included different variables. Post-surgical wound healing complications were identified using the National Cancer Institute Common Toxicity Criteria for Adverse Events (NCI-CTC) version 3.0.

Results

None of the six patients operated on presented adverse events related to the wound healing, that is to say, no wound dehiscence, wound infection, delayed wound healing, fistula formation, abscess formation or hemorrhage/bleeding associated with surgery during treatment with CIMAvax® EGF occurred.

Conclusions

These results suggest that the use of CIMAvax® EGF does not produce a deleterious effect in the wound healing process.

Beyond the standard of care: a review of novel immunotherapy trials for the treatment of lung cancer

BACKGROUND

Lung cancer is the most common cause of cancer-related death in the United States, yet traditional chemotherapy fails to provide long-term benefit for many patients. New approaches are needed to improve overall survival beyond the current standard of care.

METHODS

This review discusses recent clinical trials using immunotherapy techniques to treat both non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC) and highlights ongoing immunotherapy research efforts at our center.

RESULTS

For NSCLC, phase II clinical trials have examined allogeneic vaccines that target either mucin 1 (MUC1), epidermal growth factor or melanoma-associated antigen 3. These vaccines are now undergoing larger phase III trials. An autologous cellular therapy directed against transforming growth factor beta-2 and a recombinant protein with antitumor properties have also shown promise in prolonging survival in NSCLC in phase II trials. The monoclonal antibodies ipilimumab, BMS-936558 (anti-PD-1), and BMS936559 (anti-PD-L1) lead to enhanced T-cell-mediated antitumor effects and have produced objective responses in early-phase clinical trials. Studies for SCLC also exist, such as a novel vaccine therapy targeting p53.

CONCLUSIONS

Recent clinical trials in lung cancer demonstrate the potential of immunotherapeutics to increase overall survival in patients with lung cancer compared with the current standard of care.

Current clinical immunotherapy targets in advanced nonsmall cell lung cancer (NSCLC)

NSCLC remains one of the most challenging malignancies to treat. Despite the introduction of innovative therapies over the last decade, the 5-year survival of NSCLC is still <20%. Clearly, novel, therapeutic approaches are required. Targeting the immune system to derive meaningful clinical benefit has proved successful in various malignancies in recent years. As a result, there is renewed focus on the use of immunotherapy in lung cancer. In this review, we provide an overview of current immune-modulatory approaches in the treatment of NSCLC.

Concomitant combination of active immunotherapy and carboplatin- or paclitaxel-based chemotherapy improves anti-tumor response

Recent preclinical evidence substantially supports the successful combination of chemotherapies and active immunotherapy for cancer treatment. These data sustain the effect of sequential combination schemes (vaccine plus chemotherapy or vice versa), which could be difficult to implement in clinical practice. Since chemotherapy is the standard treatment for most cancers, ethical issues forbid its delay and make difficult the evaluation of other treatments such as using an immunotherapeutic agent. Besides, vaccines must be applied as soon as possible to advanced cancer patients, in order to give them time to develop an effective immune response. Thus, a clinically attractive scenario is the concomitant application of treatments. However, little is known about the specific effect of different chemotherapeutic agents when combined with a cancer vaccine in such concomitant treatment. In this work, we analyze the influence of high-dose carboplatin or paclitaxel in the generation of a specific immune response when administered concomitantly with an OVA vaccine. Interestingly, neither carboplatin nor paclitaxel affects the humoral and CTL in vivo response generated by the vaccine. Moreover, an enhancement of the overall anti-tumor effect was observed in animals treated with OVA/CF vaccine combined with cytotoxic drugs. Moreover, the effect of the concomitant treatment was tested using a tumor-related antigen, the epidermal growth factor (EGF). Animals administered with EGF-P64k/Montanide and cytotoxic agents showed an antibody response similar to that from control animals. Therefore, our study suggests that carboplatin and paclitaxel can be concomitantly combined with active immunotherapies in the clinical practice of advanced cancer patients.

Cancer targeting vaccines: surrogate measures of activity

Recent FDA approval of sipuleucel-T and Ipilimumab as indicated immunologic therapy in patients with advanced prostate cancer and melanoma, respectively, has established a foothold for broader utilization of vaccine based technology in managing cancer.  Despite difficulty of cell harvest and processing with sipuleucel-T and modest toxicity to Ipilimumab, when matched up with the appropriate cancer patient these immunologic approaches have provided significant benefit and have stimulated exciting forward progress in the development of new potent and less toxic (more targeted) vaccines.  However, surrogate measures of activity to optimally define more sensitive subset populations and to determine length of treatment time in order to optimize management with other treatment options remain elusive.  Key clinically tested vaccines under development which demonstrate correlation of patient benefit to induced immune responsiveness will be discussed.  Results suggest with some vaccines correlation of patient benefit and surrogate measures of activity actually do exist.  Examples will be discussed.

Active-specific immunotherapy for non-small cell lung cancer

Non-small cell lung cancer constitutes about 85% of all newly diagnosed cases of lung cancer and continues to be the leading cause of cancer-related deaths worldwide. Standard treatment for this devastating disease, such as systemic chemotherapy, has reached a plateau in effectiveness and comes with considerable toxicities. For all stages of disease fewer than 20% of patients are alive 5 years after diagnosis; for metastatic disease the median survival is less than one year. Until now, the success of active-specific immunotherapy for all tumor types has been sporadic and unpredictable. However, the active-specific stimulation of the host's own immune system still holds great promise for achieving non-toxic and durable antitumor responses. Recently, sipuleucel-T (Provenge(®); Dendreon Corp., Seattle, WA) was the first therapeutic cancer vaccine to receive market approval, in this case for advanced prostate cancer. Other phase III clinical trials using time-dependent endpoints, e.g. in melanoma and follicular lymphoma, have recently turned out positive. More sophisticated specific vaccines have now also been developed for lung cancer, which, for long, was not considered an immune-sensitive malignancy. This may explain why advances in active-specific immunotherapy for lung cancer lag behind similar efforts in renal cell cancer, melanoma or prostate cancer. However, various vaccines are now being evaluated in controlled phase III clinical trials, raising hopes that active-specific immunotherapy may become an additional effective therapy for patients with lung cancer. This article reviews the most prominent active-specific immunotherapeutic approaches using protein/peptide, whole tumor cells, and dendritic cells as vaccines for lung cancer.

CIMAvax EGF vaccine for stage IIIb/IV non-small cell lung carcinoma

This case report documents the use of the CIMAvax Epidermal Growth Factor vaccine regimen in a 54 y old female with stage IIIb non-small cell lung carcinoma. Even after 48 mo since diagnosis her ECOG performance remains at zero. Further, this report documents a reaction to the vaccine of grade 3 severity not previously documented.

The potential beneficial effects of drugs on the immune response to vaccination

Many immunotherapeutic agents in phase II cancer studies have given optimistic results, which were not confirmed in larger randomized studies. Here we explore the evidence that, contrary to previous opinion, many chemotherapeutic agents and other classes of drugs may enhance the response to therapeutic vaccines by reducing inflammation and/or by inhibiting regulatory T lymphocytes or myeloid-derived suppressor cells. In addition, some of these agents, such as the immunomodulatory drugs, may produce marked costimulatory activities as in the case of lenalidomide, which also has marked anti-inflammatory properties. With the first approval for a vaccine-based therapy for prostate cancer, we propose that many more vaccines will be able to achieve approval, especially when combined with the optimal chemotherapy and/or immunomodulatory drug schedule.

Therapeutic vaccination with an EGF-based vaccine in lung cancer: a step in the transition to a chronic disease

The trend of increased survival in advanced tumors suggests the possibility of the transformation of cancer into a chronic disease. That goal will require therapeutic weapons with low toxicity that can be used chronically. Here we summarize the development of a therapeutic vaccine consisting in recombinant EGF chemically linked to a protein from Neisseria meningitides. In mice, the vaccine elicited antibodies to self-EGF and had anti-tumor activity. Clinical trials have shown that the vaccine is also immunogenic and well tolerated in humans. The vaccination produced a decrease in plasma EGF concentration. Advanced lung cancer patients eliciting high antibody titers of EGF had better survival. The vaccine can be used long term and integrated with other treatment modalities.

Safety, immunogenicity and preliminary efficacy of multiple-site vaccination with an Epidermal Growth Factor (EGF) based cancer vaccine in advanced non small cell lung cancer (NSCLC) patients

The prognosis of patients with advanced non small cell lung (NSCLC) cancer remains dismal. Epidermal Growth Factor Receptor is over-expressed in many epithelial derived tumors and its role in the development and progression of NSCLC is widely documented. CimaVax-EGF is a therapeutic cancer vaccine composed by human recombinant Epidermal Growth Factor (EGF) conjugated to a carrier protein, P64K from Neisseria Meningitides. The vaccine is intended to induce antibodies against self EGF that would block EGF-EGFR interaction. CimaVax-EGF has been evaluated so far in more than 1000 advanced NSCLC patients, as second line therapy. Two separate studies were compared to assess the impact of high dose vaccination at multiple anatomic sites in terms of immunogenicity, safety and preliminary efficacy in stage IIIb/IV NSCLC patients. In both clinical trials, patients started vaccination 1 month after finishing first line chemotherapy. Vaccination at 4 sites with 2.4 mg of EGF (high dose) was very safe. The most frequent adverse events were grade 1 or 2 injection site reactions, fever, headache and vomiting. Patients had a trend toward higher antibody response. The percent of very good responders significantly augmented and there was a faster decrease of circulating EGF. All vaccinated patients and those classified as good responders immunized with high dose at 4 sites, had a large tendency to improved survival.

Clinical outcome of patients with various advanced cancer types vaccinated with an optimized cryptic human telomerase reverse transcriptase (TERT) peptide: results of an expanded phase II study

BACKGROUND

TERT (telomerase reverse transcriptase) plays a critical role in tumor cell growth and survival. In an expanded phase II study, we evaluated the immunological and clinical responses to the TERT-targeting Vx-001 vaccine in patients with advanced solid tumors.

METHODS

HLA-A*0201-positive patients received two subcutaneous injections of the optimized TERT(572Y) peptide followed by four injections of the native TERT(572) peptide, every 3 weeks. Peptide-specific immune responses were evaluated by enzyme-linked immunosorbent spot at baseline, and after the second and the sixth vaccinations.

RESULTS

Fifty-five patients were enrolled and 34 (62%) completed the six vaccinations. A TERT-specific T-cell immune response was observed in 55% and 70% of patients after the second and the sixth vaccinations, respectively. The disease control rate (DCR) was 36% [95% confidence interval (CI) 24% to 49%], including one complete and one partial response. Immunologically responding patients had a better clinical outcome than nonresponders [DCR: 44% versus 14% (P = 0.047); progression-free survival (PFS): 5.2 versus 2.2 months (P = 0.0001) and overall survival: 20 versus 10 months (P = 0.041)]. Multivariate analysis revealed that the immunological response was an independent variable associated with increased PFS (hazard ratio = 3.35; 95% CI 1.7-6.7).

CONCLUSION

Vx-001 vaccine was well tolerated and induced a TERT-specific immunological response, which was significantly correlated with improved clinical outcome.