Conatumumab: a novel monoclonal antibody against death receptor 5 for the treatment of advanced malignancies in adults

Introduction: Advanced malignancies that are refractory to standard chemotherapy have few treatment options. Conatumumab is an investigational, fully human monoclonal agonist antibody directed at human death receptor DR5, which is expressed in multiple advanced cancers.

Areas covered: The rationale for the use of conatumumab based on in vitro, in vivo, Phase I, and Phase II data will be discussed.

Expert opinion: Conatumumab, at a dose of 20 mg/kg every 2 weeks, has demonstrated acceptable safety and tolerability in patients with advanced tumors based on available and published data. Further clinical trials are underway evaluating the use of conatumumab in combination with chemotherapeutic and targeted agents.     

Zalutumumab in head and neck cancer

INTRODUCTION: Over 90% of head and neck cancers overexpress EGFR. This correlates with advanced disease stage and worse prognosis. Strategies to inhibit the EGFR pathway have been developed over the last decade. Zalutumumab is a recent high-affinity completely human IgG1k antibody targeting EGFR. AREAS COVERED: The mechanism of action and data on efficacy and safety of zalutumumab in head and neck cancer. EXPERT OPINION: Zalutumumab has demonstrated acceptable toxicity in head and neck cancer patients, with rash being the most common adverse event. The toxicity profile makes zalutumumab an attractive option for patients who are heavily pretreated and/or have poor performance status due to concurrent co-morbidities. As the molecule is fully human, the likelihood of hypersensitivity to the drug is low. Zalutumumab may be effective at low concentrations through antibody-dependent cellular cytotoxicity. Current data from Phase I and II trials identify zalutumumab as a promising drug for the treatment of locally advanced head and neck cancer and recent data from a Phase III randomized trial showed encouraging survival results compared with best supportive care. Results from other ongoing Phase III trials will provide clarification on zalutumumab as a treatment option. The clinical development of this compound has been suspended from June 2011 until a development and commercialization partner is found.     

The immunological era in melanoma treatment: new challenges for heat shock protein-based vaccine in the advanced disease

INTRODUCTION: Tumor-derived heat shock protein (HSP)-peptide complexes (HSPPCs) induced immunity against malignancies in preclinical trials, working across tumor types and bypassing the need to identify single immunogenic peptides. These results paved the way for the use of human gp96 obtained from autologous tumor samples as an anti-cancer vaccine. AREAS COVERED: Autologous tumor-derived HSP gp96 peptide complex (HSPPC-96) vaccine is emerging as a tumor- and patient-specific cancer vaccine, with confirmed activity in several malignancies. It has been tested in Phase III clinical trials in advanced melanoma and kidney cancer with evidence for efficacy in patients with earlier stage disease. HSPPC-96-based vaccine demonstrated an excellent safety profile, thus emerging as a novel therapeutic approach with a suggestive role in cancer therapy. This review summarizes work on the use of HSPPC-96 as an autologous anti-tumor vaccine in advanced melanoma. Data were retrieved by PubMed and Medline research and using the authors' personal experience. EXPERT OPINION: Further investigations are needed to understand the biological basis of immune functions in order to improve the clinical outcome of HSP-based cancer therapy. In the near future, the combination of HSP-based vaccines with other biological compounds might represent a successful strategy in the therapy of advanced melanoma.     

Trastuzumab emtansine: a novel antibody-drug conjugate for HER2-positive breast cancer

INTRODUCTION: Trastuzumab emtansine (T-DM1) is an antibody-drug conjugate (ADC) that combines intracellular delivery of the potent cytotoxic agent, DM1 (a derivative of maytansine) with the antitumor activity of trastuzumab. While there are several ADCs in Phase III development, T-DM1 is the only one in which the targeting antibody has antitumor properties. T-DM1 is also the only ADC that is directed toward the human EGFR 2 (HER2). Effective therapies are limited in HER2-positive advanced or metastatic breast cancer (MBC), particularly following progression on available HER2-targeted therapies. AREAS COVERED: The mechanisms of action, preclinical efficacy and clinical profile of T-DM1 are reported. The latest preclinical and clinical data for T-DM1 are examined. EXPERT OPINION: T-DM1 has significant antitumor potency in vitro and in vivo, which is maintained in tumors resistant to trastuzumab or lapatinib. In Phase I and II trials, T-DM1 provided objective tumor responses and was well tolerated across various lines of therapy in patients with HER2-positive MBC. In addition, it showed similar efficacy to trastuzumab plus docetaxel in first-line MBC. Ongoing trials (including two Phase III studies) are investigating T-DM1 as single-agent therapy or combined with other chemotherapeutic or biologic agents, and the results should help to define the place of T-DM1 within current treatment algorithms for HER2-positive disease.     

Lapatinib: a novel dual tyrosine kinase inhibitor with activity in solid tumors

OBJECTIVE: To review the pharmacology, pharmacokinetics, clinical trials, adverse effects, and drug interactions of lapatinib. DATA SOURCES: A PubMed search was conducted (1966-August 2005) using the following terms: lapatinib, GW572016, and dual tyrosine kinase inhibitor. Additional information sources included meeting abstracts, clinical trial data, and bibliographies from articles identified through PubMed. STUDY SELECTION AND DATA EXTRACTION: Preclinical and clinical trials that evaluated lapatinib in cell culture, animal models, and human subjects were selected from the data sources. Pivotal in vitro data and all in vivo data published regarding lapatinib were included. DATA SYNTHESIS: The development of tyrosine kinase inhibitors has resulted from a search for targeted cancer therapeutics made possible by recent gains in our understanding of tumor cell biology. Lapatinib is a dual tyrosine kinase inhibitor selective for inhibition of epidermal growth factor receptor and human epidermal growth factor receptor-2 autophosphorylation, leading to suppression of proliferation pathways of solid tumors. Lapatinib has shown clinical activity in solid tumors, with the most notable in advanced or metastatic breast cancer, including tumors refractory to trastuzumab. It has a mild adverse effect profile, with the most common adverse events being diarrhea and rash. CONCLUSIONS: Lapatinib has novel, dual tyrosine kinase inhibitory properties selective for factors overexpressed in some solid tumors. Results from preclinical and Phase I/II trials indicate activity in the treatment of solid tumors, especially advanced or metastatic breast cancer. Application for approval is anticipated pending results of ongoing Phase III trials.     

The technique of reversing ventricular fibrillation: improve the odds of success with this five-phase approach

Early, repeated defibrillation is the key to managing ventricular fibrillation (VF). To maximize the likelihood of success, use this five-phase approach, modified from the advanced cardiac life support protocols. Phase I: When a patient is found in VF and with no pulse or signs of life, attempt electrical reversion with a 200-wsec shock, followed if necessary by a 300-wsec and a 360-wsec shock. Phase II: Manage reversible causes of VF with orotracheal intubation, hyperventilation, and epinephrine. Phase III: Use intravenous lidocaine aggressively, followed by a 360-wsec shock. Phase IV: Give bretylium and magnesium sulfate by intravenous push, again followed by a 360-wsec shock. Phase V: Treat refractory VF with repeated 360-wsec shocks, and give further doses of the anti-arrhythmic agents.     

Role of MetMAb (OA-5D5) in c-MET active lung malignancies

INTRODUCTION: MetMAb (OA-5D5) is a one-armed monoclonal antibody developed to bind to and inhibit c-MET receptor tyrosine kinase. Though only in early clinical testing, this agent holds great promise in diseases thought to be driven by c-MET activation, as evidenced by the Phase II results in NSCLC where a benefit in overall survival was observed in patients with MET-diagnostic-positive disease. Thus far, both alone and in combination with other targeted agents, this drug has been well tolerated and no new significant safety signals have been identified. AREAS COVERED: This review summarizes the structure and function of the c-MET receptor and its ligand hepatic growth factor (HGF), provides an overview of select targeted monotherapies developed to interfere in the MET-HGF signaling pathway, discusses pre-clinical and clinical data surrounding MetMAb, and concludes with an expert opinion regarding this novel agent. EXPERT OPINION: MetMAb has been well tolerated and based on Phase II data testing it, in combination with erlotinib in advanced NSCLC, may have a role in improving survival in patients with disease driven by c-MET activation. However, Phase III validation is underway and the results of these studies will help elucidate which patients will benefit most from this novel agent.     

Studying communication in oncologist-patient encounters: the SCOPE Trial

STUDY OBJECTIVE: Most oncologists have not received adequate training in physician-patient communication, and existing effective courses tend to be time and resource intensive. We are developing and testing a tailored CD-ROM educational intervention that includes feedback on oncologists' own audio-recorded conversations with their advanced cancer patients. In this report, we describe the study methods and identify challenges to implementation and how these were overcome. STUDY DESIGN: A three-phase, randomized, controlled trial. In Phase 1, we audio-recorded oncologist-patient clinic encounters. In Phase 2, oncologists were randomly assigned to a communication CD-ROM intervention or control. Phase 3 consisted of audio-recording all participating oncologists conversing with a new sample of patients, two to 12 months after the intervention, to assess its effectiveness. SETTING: Oncology clinics at Duke University Medical Center (DUMC) and the Durham Veterans Affairs Medical Center (DVAMC) in Durham, NC, and the University of Pittsburgh Medical Center (UPMC) in Pittsburgh, PA. PARTICIPANTS: Medical, radiation and gynecological oncologists and their patients with advanced cancer. INTERVENTION: A tailored CD-ROM that contains an interactive educational interface with reference materials and video-clips of model conversations, along with the oncologists' own Phase 1 audio-recorded conversations. CONCLUSION: We present challenges and solutions to oncologist recruitment, identifying appropriate patients with advanced cancer, adapting to clinic flow, and developing a self-administered communications intervention.     

Oncolytic vaccinia virus for the treatment of cancer

INTRODUCTION: Gene therapy offers promising approaches for the development of anticancer agents with new modes of action. Among gene therapy vectors, vaccinia virus has emerged as an attractive agent especially when used as an oncolytic virus. AREAS COVERED: This review describes the use of vaccinia virus in cancer therapy as a gene therapy vector, as an oncolytic virus and in the generation of oncolysates. The main achievements of each field are summarized with a special emphasis on vaccinia as an oncolytic vector and its combination therapies. The virus that has advanced furthest in clinical trials, GM-CSF expressing JX-594, is described in detail and its preclinical and clinical data are reviewed. EXPERT OPINION: Vaccinia virus has great potential in cancer gene therapy, especially when used as an oncolytic virus. In particular, JX-594 has shown promising preclinical and clinical data, and a multi-continental randomized Phase III trial in hepatocellular carcinoma is expected to start soon.     

Necitumumab in the treatment of advanced non-small cell lung cancer: translation from preclinical to clinical development

INTRODUCTION: Treatment outcomes in unselected patients with advanced NSCLC remain disappointing with platinum-based chemotherapy. The addition of monoclonal antibodies targeting EGFR to standard first-line therapy is a validated strategy and has been associated with statistically significant survival advantage in advanced NSCLC. Necitumunab is a fully human IgG1 monoclonal antibody targeting EGFR, having the potential benefit of lower hypersensitivity reaction risk as compared with cetuximab and also equivalent antibody-dependent cell-mediated cytotoxicity. AREAS COVERED: This paper reviews literature on preclinical and early clinical development of necitumumab that is available in PubMed and published abstracts from conferences, as well as ongoing trials as specified by clinicaltrials.gov. Recently, the Phase III clinical trial evaluating the addition of necitumumab to pemetrexed and cisplatin in non-squamous NSCLC was prematurely closed due to concerns about the increased risk of thromboembolic events in the experimental arm. Accrual in the Phase III trial of necitumumab in combination with gemcitabine and cisplatin in squamous NSCLC is ongoing. EXPERT OPINION: Results of the ongoing large randomized trials will be instrumental in determining the drug's clinical significance and, with the analysis of potential molecular predictive factors, are expected to bring valuable additions to future therapeutic strategies in NSCLC.     

The use of an antibody drug conjugate, glembatumumab vedotin (CDX-011), for the treatment of breast cancer

INTRODUCTION: Breast cancer (BC) is the most common malignancy in women in the USA. Despite the multi-modality treatments that are currently available, advanced BC has a persistent and unacceptable mortality rate. The need for new therapeutic strategies is extremely high. Experimental approaches with targeted therapies such as antibody drug conjugates provide hope for future treatment possibilities. AREAS COVERED: The development status and the possible role of antibody-mediated cytotoxic therapy are discussed in the setting of advanced BC. An overview of, mechanism of action, preclinical and Phase I/II results of glembatumumab vedotin (CDX-011) are discussed. EXPERT OPINION: The evidence that the glycoprotein NBM (GPNMB) target is a relevant target in BC, along with data showing that CDX-011 is safe and active in patients with advanced BC, provide a strong rationale to continue to explore this drug in patients with GPNMB-expressing breast tumors.     

Trastuzumab emtansine: a novel antibody-drug conjugate for HER2-positive breast cancer

Introduction: Trastuzumab emtansine (T-DM1) is an antibody–drug conjugate (ADC) that combines intracellular delivery of the potent cytotoxic agent, DM1 (a derivative of maytansine) with the antitumor activity of trastuzumab. While there are several ADCs in Phase III development, T-DM1 is the only one in which the targeting antibody has antitumor properties. T-DM1 is also the only ADC that is directed toward the human EGFR 2 (HER2). Effective therapies are limited in HER2-positive advanced or metastatic breast cancer (MBC), particularly following progression on available HER2-targeted therapies.

Areas covered: The mechanisms of action, preclinical efficacy and clinical profile of T-DM1 are reported. The latest preclinical and clinical data for T-DM1 are examined.

Expert opinion: T-DM1 has significant antitumor potency in vitro and in vivo, which is maintained in tumors resistant to trastuzumab or lapatinib. In Phase I and II trials, T-DM1 provided objective tumor responses and was well tolerated across various lines of therapy in patients with HER2-positive MBC. In addition, it showed similar efficacy to trastuzumab plus docetaxel in first-line MBC. Ongoing trials (including two Phase III studies) are investigating T-DM1 as single-agent therapy or combined with other chemotherapeutic or biologic agents, and the results should help to define the place of T-DM1 within current treatment algorithms for HER2-positive disease.     

The immunological era in melanoma treatment: new challenges for heat shock protein-based vaccine in the advanced disease

Introduction: Tumor-derived heat shock protein (HSP)–peptide complexes (HSPPCs) induced immunity against malignancies in preclinical trials, working across tumor types and bypassing the need to identify single immunogenic peptides. These results paved the way for the use of human gp96 obtained from autologous tumor samples as an anti-cancer vaccine.

Areas covered: Autologous tumor-derived HSP gp96 peptide complex (HSPPC-96) vaccine is emerging as a tumor- and patient-specific cancer vaccine, with confirmed activity in several malignancies. It has been tested in Phase III clinical trials in advanced melanoma and kidney cancer with evidence for efficacy in patients with earlier stage disease. HSPPC-96-based vaccine demonstrated an excellent safety profile, thus emerging as a novel therapeutic approach with a suggestive role in cancer therapy. This review summarizes work on the use of HSPPC-96 as an autologous anti-tumor vaccine in advanced melanoma. Data were retrieved by PubMed and Medline research and using the authors' personal experience.

Expert opinion: Further investigations are needed to understand the biological basis of immune functions in order to improve the clinical outcome of HSP-based cancer therapy. In the near future, the combination of HSP-based vaccines with other biological compounds might represent a successful strategy in the therapy of advanced melanoma.     

Abagovomab for ovarian cancer

INTRODUCTION: Ovarian cancer (OC) is the fifth most common cancer in women. Unfortunately, more than 70% of cases are detected at an advanced stage with a risk of recurrence, after front line therapy, of over 75%. The need for new therapeutic strategies is extremely high. AREAS COVERED: The development status and the possible role of specific immunotherapy of abagovomab are discussed in the context of the possible therapeutic options for maintenance therapy in advanced OC. An overview of abagovomab, generation and mechanism of action, Phase I/II results and the status of the Phase II/III ongoing trial is given. EXPERT OPINION: Abagovomab stimulates the humoral immune response and the cell-mediated immune response in the studies conducted to date. In the proof of concept (POC) study abagovomab prolonged overall survival in those OC recurrent patients who showed an immune response. Abagovomab has an excellent safety and tolerability profile. These characteristics make abagovomab an optimal candidate for a maintenance treatment for OC patients after frontline therapy. The final results of the Phase II/III pivotal study evaluating abagovomab in this setting will be available in the first half of 2011.     

Successful development and clinical translation of a novel anterior lamellar artificial cornea

Blindness due to corneal diseases is a common pathology affecting up to 23 million individuals worldwide. The tissue‐engineered anterior human cornea, which is currently being tested in a Phase I/II clinical trial to treat severe corneal trophic ulcers with preliminary good feasibility and safety results. This bioartificial cornea is based on a nanostructured fibrin–agarose biomaterial containing human allogeneic stromal keratocytes and cornea epithelial cells, mimicking the human native anterior cornea in terms of optical, mechanical, and biological behavior. This product is manufactured as a clinical‐grade tissue engineering product, fulfilling European requirements and regulations. The clinical translation process included several phases: an initial in vitro and in vivo preclinical research plan, including preclinical advice from the Spanish Medicines Agency followed by additional preclinical development, the adaptation of the biofabrication protocols to a good manufacturing practice manufacturing process, including all quality controls required, and the design of an advanced therapy clinical trial. The experimental development and successful translation of advanced therapy medicinal products for clinical application has to overcome many obstacles, especially when undertaken by academia or SMEs. We expect that our experience and research strategy may help future researchers to efficiently transfer their preclinical results into the clinical settings.     

Lapatinib: a dual inhibitor of EGFR and HER2 tyrosine kinase activity

Lapatinib (GW 572016) is an oral inhibitor of the tyrosine kinase activity of epidermal growth factor receptor (EGFR) and human EGFR-2 (HER2), which are both frequently altered in human malignant tumors. Being a multitargeting agent, it has the theoretical ability to provide more efficient antitumor activity and delay the onset of tumor resistance. Based on promising preclinical results, lapatinib is being extensively studied in cancer patients. In Phase I clinical trials, the side effect profile of lapatinib results are favorable, with a few patients experiencing serious toxicity. Phase II studies showed that lapatinib has meaningful clinical activity in the setting of HER2-positive advanced breast cancer patients. Unfortunately, its activity in epidermal growth factor receptor-dominated cancers, such as colorectal cancer or squamous cell carcinoma of the head and neck, is modest. An extensive program is now ongoing in breast cancer patients to establish the correct role of lapatinib in this clinical setting. Studies in breast cancer, as well as in other solid tumors are also collecting a large amount of biological data. Correlative studies will hopefully clarify predictive factors of lapatinib efficacy that can be applied in clinical practice in order to select patients for treatment.     

G17DT: an antigastrin immunogen for the treatment of gastrointestinal malignancy

G17DT (Gastrimmune) is an antigastrin-17 immunogen, raising antibodies that blockade gastrin-stimulated tumor growth. It has completed Phase III trials in patients with pancreatic cancer, and Phase III trials in gastric cancer are planned. Preclinical studies have confirmed that the G17DT-induced antibodies both reduce gastrin-17-stimulated gastric acid secretion and inhibit gastrin from interacting with the cholecystokinin-2 receptor. The efficacy of both passive and active immunization with G17DT has been established in a number of tumor systems, with additive effects demonstrated in combination chemotherapy in pancreatic, colon and gastric tumor models. Phase I/II studies in advanced gastrointestinal malignancies have shown no systemic or autoimmune reactions to active immunization with G17DT. The use of an optimized dose and dosing schedule has yielded a high proportion of antibody responders (70%), with minimal side effects and antibody titers measurable within 2 - 4 weeks. Phase II trials of G17DT in combination with chemotherapy have also been conducted in gastric and colorectal cancer. A Phase III, multicenter, double-blind, randomized, controlled trial of G17DT versus placebo in patients with advanced pancreatic cancer confirmed improved survival of patients in the G17DT group through an intention-to-treat analysis. The results of a randomized, double-blind, multinational, multicenter study of G17DT in combination with gemcitabine versus placebo and gemcitabine in patients with advanced pancreatic cancer failed to show improved overall survival except on subset analysis of patients with high antibody titers. Therefore, G17DT represents an emerging new modality for gastrointestinal malignancy.