Inhibition of placenta growth factor with TB-403: a novel antiangiogenic cancer therapy

INTRODUCTION: There is clinical evidence that therapies targeting the vascular endothelial growth factor pathway are effective in delaying cancer progression. However, tumors may be either intrinsically resistant or evolve resistance to such therapies. Hence, there is a need for new therapies targeting angiogenesis. AREAS COVERED: The data are obtained by searching in the PubMed database. The search terms used included antiangiogenic therapy, TB-403 (RO5323441), placenta growth factor (PlGF) and VEGFR-1 (Flt-1). We review preclinical data concerning the function and inhibition of PlGF and summarize data on expression of PlGF in cancer patients. Data from early-phase clinical trials of TB-403 (RO5323441), a monoclonal antibody inhibiting PlGF, are discussed. Future development strategies, therapeutic potentials and limitations of TB-403 are further evaluated. EXPERT OPINION: There are some conflicting data on the function of PlGF and the importance of its role in primary tumor growth. Data from some preclinical models of PlGF inhibition and early-phase clinical trials with TB-403 are, however, promising, although the true potential of the drug is yet to be determined. Further clinical development should be preceded by molecular studies in the context of well-designed preclinical models and/or small translational studies. Future challenges involve identifying predictive biomarkers.     

The use of desmoteplase (bat saliva) in the treatment of ischaemia

Introduction: In an era of ageing global populations and accumulation of cardiovascular risk factors, the importance of reperfusion/recanalisation therapies in treating vascular occlusive disease is growing. There are multiple thrombolytic agents available, including bat saliva-derived plasminogen activator.

Areas covered: A peer reviewed literature search was conducted and focus was on the data on the use of desmoteplase in the treatment of ischaemic stroke.

Expert opinion: Currently, there is not enough evidence for clinical use in ischaemic stroke and further Phase III studies are underway. At this stage, desmoteplase remains an investigational compound.     

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.     

Carfilzomib in multiple myeloma

Introduction: Advances in drug therapy for multiple myeloma (MM) during the previous decade have improved survival outcomes; however, the disease remains incurable as patients eventually relapse or become refractory to all available therapies. Therefore, there is a clear need for more effective and well-tolerated treatments.

Areas covered: We review preclinical and clinical data regarding the use of carfilzomib, a proteasome inhibitor that is structurally and mechanistically distinct from bortezomib, for the treatment of MM patients. Carfilzomib pharmacokinetics, pharmacodynamics, efficacy, safety and tolerability are summarized, based on Phase I/II trial data.

Expert opinion: Carfilzomib represents a significant advance in the management of relapsed and/or refractory MM patients, including those intolerant or resistant to bortezomib. High response rates have been demonstrated with carfilzomib as a single agent or in combination with alkylating agents, immunomodulators and corticosteroids, even among patients who have failed multiple prior therapies. Carfilzomib also has significant potential in the frontline setting, with encouraging response and survival rates observed for combination regimens. Further evaluation of carfilzomib-containing regimens is ongoing in Phase III trials and investigator-sponsored studies, which include combinations with novel investigational agents. These findings will shape the future role of carfilzomib for MM patients across multiple settings.     

Trastuzumab emtansine in breast cancer

Introduction: Trastuzumab emtansine (T-DM1) is a human epidermal growth factor receptor 2 (HER2)–targeted antibody–drug conjugate (ADC) composed of trastuzumab, a stable linker (MCC), and the cytotoxic agent DM1 (derivative of maytansine). Administration of T-DM1 leads to limited systemic exposure of free DM1, with no evidence of DM1 accumulation after repeated dosing.

Areas covered: Phase I and Phase II clinical trials with T-DM1 as a single agent and in combination with paclitaxel, docetaxel, and pertuzumab have shown substantial clinical activity and a favorable safety profile. A randomized, open-label, first-line trial comparing trastuzumab and docetaxel with single agent T-DM1 showed a significant improved progression-free survival for T-DM1.

Expert opinion: T-DM1 has successfully completed second-line Phase III development for advanced HER2-positive breast cancer. The Phase III EMILIA study demonstrated an overall survival benefit for T-DM1 compared to the combination of lapatinib and capecitabine in taxane-trastuzumab pretreated patients. T-DM1 may offer delivery on a personalized basis of very potent cytotoxic agents in a cellular selective manner.     

Current opinion on bevacizumab on endometrial cancer treatment

Introduction: Advanced or recurrent endometrial cancer is still a challenge for clinicians as it has a poor prognosis despite treatment efforts. Thus, there is an urgent need for new agents with activity in this subset of patients. The increased knowledge of the molecular aspects of endometrial carcinogenesis has led to the development of molecular targeted therapies and in particular anti-angiogenic drugs. One of the most promising of these agents is bevacizumab, a recombinant humanized immunoglobulin monoclonal antibody to VEGF.

Areas covered: The objective of this paper is to discuss the role of angiogenesis in endometrial cancer and analyze the rational of bevacizumab use, alone or in combination with other therapies, in endometrial cancer patients. We reviewed the most important preclinical and clinical studies published on this topic up to March 2014.

Expert opinion: Bevacizumab in combination with others targeted therapies, chemotherapy or radiotherapy demonstrated promising anti-tumor activity. Despite the good oncological outcomes of these recent clinical experiences, caution must be used in light of significant toxicity reported in this subset of heavily pre-treated patients. The identification of biomarkers able to predict either the efficacy or toxicity of anti-angiogenic drugs is a compelling need.     

Remestemcel-L for acute graft-versus-host disease therapy

Introduction: Remestemcel-L (Prochymal®, Osiris) is an off-the-shelf adult mesenchymal stromal cell product that has been applied to acute graft-versus-host disease (aGvHD) for its immunomodulatory properties.

Areas covered: This article discusses preclinical and clinical studies supporting the use of remestemcel-L in aGvHD as well as the current regulatory status. This information was based upon a PubMed and Internet search.

Expert opinion: Phase II studies suggest remestemcel-L may have clinical activity in aGvHD and confirm tolerability. However, these results must be interpreted cautiously with any use of remestemcel-L optimally occurring in the context of a clinical trial. Further clarity will be obtained when the results of a completed Phase III study are published. There is a small market for remestemcel-L in aGvHD. A possible future scenario is that a more prevalent indication is found and remestemcel-L is approved for that indication, but use continues for aGvHD.     

Clinical experience with ramucirumab: outcomes in breast cancer

Introduction: Monoclonal antibodies and small molecules targeting the VEGF pathway are part of the arsenal to treat malignant tumors. Antiangiogenesis therapies has been studied in breast cancer with partial success, reflected by the approval of bevacizumab in Europe but not in United States, for metastatic breast cancer (mBC). Ramucirumab is a mAb against VEGFR-2 interfering with the normal activation of this receptor by its natural ligand VEGF.

Areas covered: This article will review the preclinical data available to date for ramucirumab, as well as survey the main clinical trials of antiangiogenic agents reported in breast cancer, focusing on Phase III clinical trials. It will also review the clinical trial data for ramucirumab in mBC, including the design of the Phase II trials, and report on the preliminary results of the TRIO-012 trial. This trial did not meet its primary end point in progression-free survival and has to be considered as a negative trial.

Expert opinion: Despite preliminary positive data with ramucirumab in other metastatic solid tumors reported to date, the results of TRIO-012 discourage pursuing more efforts with ramucirumab in mBC unless predictive and reproducible biomarkers can be established to select those patients who are most likely to benefit from it.     

Is there still a role for abatacept in the treatment of lupus?

Introduction: The quest for safer and more effective treatments for systemic lupus erythematosus (SLE) has led to the development of many new biologic therapies. Abatacept is the first drug targeting co-stimulation between T cells and antigen presenting cells, with abundant pre-clinical evidence to support its use in SLE.

Areas covered: This review will present the relevant aspects of lupus pathophysiology pertaining to the mechanism of action of abatacept, a summary of murine studies and the latest human clinical trials.

Expert opinion: Abatacept has demonstrated efficacy in both rheumatoid arthritis and psoriatic arthritis, and earlier studies have suggested tantalising evidence of efficacy in SLE. However, the latest randomised double-blinded study showed disappointingly negative results, much like the case of rituximab in SLE. Currently, abatacept remains a possible therapeutic option as an off-label therapy, and it is a part of our therapeutic armamentarium in difficult cases. The need to find appropriate definitions of response and optimal study design continues to be paramount in the field of lupus therapies.     

Ipilimumab in prostate cancer

Introduction: Immune checkpoint inhibitors, such as ipilimumab, are a new class of immunotherapeutic agents that have shown significant efficacy in melanoma. A number of ongoing clinical trials are investigating the role of ipilimumab in prostate cancer, either alone or in combination with immunomodulating agents such as radiation and chemotherapy, and in combination with cancer vaccines.

Areas covered: This article reviews the molecular basis, preclinical and clinical evidence on the safety and efficacy of ipilimumab in prostate cancer. Medical literature search using MEDLINE and online abstracts database of national meetings form the basis of this article.

Expert opinion: A number of preliminary clinical studies suggest the potential therapeutic utility of immune checkpoint inhibitors such as ipilimumab in prostate cancer. Pending the results of large-scale studies, the rationale of combining ipilimumab with standard anticancer therapeutics such as radiation, cytotoxic chemotherapy and other immunotherapeutic agents can be of great value in reducing mortality and morbidity in prostate cancer.     

Pegylated-IFNα2a for HIV/hepatitis C virus coinfected patients: out with the old,in with the new

Introduction: Liver disease is a major burden in patients co-infected with HIV and hepatitis C virus (HCV). From the time of its approval, pegylated-IFNα-2a (pegIFN-α2a) has played a major role in treatment of HCV in HIV/HCV co-infection.

Areas covered: This article briefly summarizes the epidemiology of HCV/HIV co-infection, the pharmacokinetic, and pharmacodynamic properties of pegIFN-α2a. Results from clinical trials investigating therapies containing pegIFN-α2a for HIV/HCV co-infected patients will be discussed with a focus on efficacy and safety.

Expert opinion: PegIFN-α2a has improved rates of sustained virologic response for co-infected patients. In combination with direct-acting antivirals (DAA), the disparity between mono- and co-infected patients is beginning to disappear. For the first time, IFN-free regimens are available in clinical practice. It is unlikely that pegIFN-α2a will continue to be a critical component in treatments for HCV in the general co-infected population.     

Update of cetuximab for non-melanoma skin cancer

Introduction: Non-melanoma skin cancer (NMSC) has become the most common malignancy in humans. Targeted therapies are recent developments for these tumors. Monoclonal antibody cetuximab has proven its efficacy and has improved tolerability compared to classical chemotherapy protocols, and this prompted us to analyze new data on the use of cetuximab in cutaneous NMSC.

Areas covered: The monoclonal antibody cetuximab against epidermal growth factor receptor (EGFR) has been investigated for its use in NMSC during the years between 2011 and 2013. A PUBMED research 2011 – 2013 has been conducted using the following terms: ‘Non-melanoma skin cancer AND cetuximab’, ‘cutaneous squamous cell carcinoma AND cetuximab’, and ‘basal cell carcinoma AND cetuximab’ and ‘cetuximab AND skin toxicity’. Available data were analyzed – irrespective of their level of evidence, that is, case reports and case series were included.

Expert opinion: Current evidence of cetuximab's efficacy in NMSC was mainly obtained in cutaneous squamous cell carcinoma (SCC) and to a lesser extent in basal cell carcinoma (BCC). Response rates vary for neoadjuvant, adjuvant, monotherapy and combined therapy with cetuximab. Limitations are the low number of patients treated (33 patients with SCC, 4 patients with BCC) and the low quality of studies reported. Management of cutaneous toxicities of EGFR inhibitors is necessary, and guidelines are available. Proactive therapy might also prevent skin toxicity of higher grades, with EGFR inhibitor cetuximab as an option for recurrent or advanced NMSC of the skin. It seems to be justified particularly in very high risk epithelial tumors. There is an urgent need for Phase III trials. In the future, combined drug therapy with other monoclonal antibodies and/or radiotherapy may further improve efficacy and response rates for NMSC.     

Belagenpumatucel-L for the treatment of non-small cell lung cancer

Introduction: Immunotherapy has become a promising approach for the treatment of NSCLC. In order to stimulate the host immune system against tumour antigens, several cancer vaccines have been generated and evaluated. Belagenpumatucel-L is a whole tumour cell vaccine expressing the antisense strand of the TGF-β2 gene.

Areas covered: The purpose of this article is to review the most relevant findings of clinical trials testing belagenpumatucel-L in advanced NSCLC patients.

Expert opinion: Although the Phase III trial investigating belagenpumatucel-L in stage III/IV patients did not meet its primary end point, a survival benefit was observed in several subgroups of patients. Further studies are needed in order to select patients who may benefit from this vaccine.     

Ipilimumab in the treatment of advanced melanoma – a clinical update

Introduction: Ipilimumab has become an important treatment option for patients with advanced melanoma; however, active research perseveres to resolve many clinical practice issues and to further improve the therapeutic index of this agent.

Areas covered: This article aims to provide an update on long-term data, current challenge and recent progress relating to the clinical application of ipilimumab in the treatment of advanced melanoma. A literature search using PubMed database was conducted using search words ipilimumab, melanoma, treatment sequencing, adjuvant therapy, combination therapy, and biomarkers. Data were also obtained from meeting abstracts and clinical trial registries.

Expert opinion: Signal of clinical activity as adjuvant therapy in patients with resected high-risk melanoma begins to emerge, but longer follow-up is required for confirmation. Many issues, such as optimal dosing schedules and therapeutic sequences, remain unraveled. At present, treatment should be individualized based on patient- and disease-specific factors. Immunotherapy like ipilimumab still represents the best treatment option for durable remission; however, targeted therapies are more appropriate for patients with BRAF V600-mutated tumor who are symptomatic or have rapidly growing disease. With novel therapeutic options in the pipeline, the role of ipilimumab continues to evolve in the rapidly changing treatment landscape of advanced melanoma. Most likely, this agent will be utilized in combinatorial or sequential approach.     

Contemporary use of bevacizumab in ovarian cancer

Introduction: Ovarian cancer remains the most lethal gynecologic malignancy. Although standard platinum-based chemotherapy results in high response rates, more than 70% of patients with advanced disease will experience recurrence within 5 years. Therefore, novel treatment strategies to increase primary efficacy, decrease recurrence after primary treatment and improve the response rate for recurrent disease are needed.

Areas covered: This review covers antiangiogenesis therapy and the efficacy of bevacizumab as primary treatment and in platinum-sensitive and resistant recurrent disease.

Expert opinion: The evidence provided from Phase III trials has supported the efficacy of bevacizumab in primary and recurrent ovarian cancer management. Future investigation is needed to improve clinical performance (via biomarkers of efficacy, early discontinuation, additional agents, etc.), as well as, more sensitive tools to assess direct patient impact.     

Pidilizumab in the treatment of diffuse large B-cell lymphoma

Introduction: The programmed death-1 (PD-1) immune checkpoint pathway is an emerging target in the treatment of hematologic malignancies. Pidilizumab is an mAb that binds to PD-1 and is a safe and well-tolerated therapy. Recent data have shown clinical activity utilizing this strategy in diffuse large B-cell lymphoma (DLBCL).

Areas covered: The role of PD-1 expression in hematologic malignancies is explored. Recent clinical trials including the results of a Phase I trial in hematologic malignancies and a Phase II trial of pidilizumab following autologous hematopoietic stem-cell transplant (AHSCT) are reviewed.

Expert opinion: We review data that suggest that PD-1 is a promising target in the treatment and management of DLBCL. Changes in immune subsets following administration of pidilizumab are felt to represent on-target responses. The improvement in progression-free survival (PFS) following AHSCT supports a response to therapy. Importantly, the improvement in PFS for patients with positive FDG-PET/CT following AHSCT indicating residual disease further supports direct activity of pidilizumab in DLBCL.     

Adalimumab in the treatment of plaque-type psoriasis and psoriatic arthritis

Introduction: Psoriasis and psoriatic arthritis (PsA) are chronic immune-mediated diseases, and TNF-α (tumor necrosis factor) is a pro-inflammatory cytokine that plays a critical role in the pathogenesis of these conditions. Adalimumab is an anti-TNF-α drug widely used for the treatment of both psoriasis and PsA. Controlled clinical trials demonstrated that adalimumab is characterized by a high degree of clinical response. The aim of this review is to report the safety, efficacy, and recent findings in the treatment of psoriasis and PsA with adalimumab.

Areas covered: This article reviews the results of Phase II, III, controlled, and observational clinical studies on adalimumab in the treatment of psoriasis and PsA. A systematic search was conducted using the Pubmed Medline database for primary articles.

Expert opinion: Treatment of psoriasis and PsA represents a therapeutic challenge for dermatologists and rheumatologists. The efficacy, tolerability, and safety profiles suggest adalimumab as a suitable anti-psoriatic drug in the long-term treatment of psoriasis and PsA. Management of long-term treatment, loss of efficacy, and comorbidities has been described.     

Brodalumab-an IL-17RA monoclonal antibody for psoriasis and psoriatic arthritis

Introduction: IL-17 is a growing target for autoimmune and inflammatory diseases. Brodalumab is a fully human anti-IL-17RA monoclonal antibody that has been investigated in a range of disease including psoriasis, psoriatic arthritis, rheumatoid arthritis, inflammatory bowel disease and asthma.

Areas covered: This review aims to summarize up-to-date pharmacological properties of brodalumab and the clinical efficacy and safety data presented in clinical trials. The focus of this review will be on psoriasis, psoriatic arthritis and rheumatoid arthritis although we will briefly touch on the other indications in which the drug has been studied as we feel it adds to our understanding of the IL-17 pathway and highlights areas where research is still needed.

Expert opinion: Brodalumab has shown good efficacy in psoriasis in small but extended studies with a moderate effect on psoriatic arthritis. Brodalumab studies are clearly negative in rheumatoid arthritis and inflammatory bowel disease. The data are equivocal in asthma; however, further studies in this disease are justifiable. The safety profile of this drug thus far is not worrisome although longer studies in more patients are needed.     

Evaluation of aflibercept in the treatment of metastatic colorectal cancer

Introduction: Colorectal cancer (CRC) is currently the third most common cancer worldwide, with up to 1 million new cases diagnosed each year. Despite improvements in clinical outcomes of patients with this tumor over the past decades, prognosis remains poor with a 5-year survival rate of < 10%. The currently available systemic chemotherapeutic options for patients with colon cancer consist essentially of fluoropyrimidine-based regimens, alone or in combination with oxaliplatin or irinotecan. The addition of the anti-vascular endothelial growth factor (VEGF) monoclonal antibody (mAb) bevacizumab to the above mentioned first- or second-line chemotherapies has demonstrated an improvement in overall survival and a delay in disease progression. Aflibercept is a recombinant protein from the domain 2 of the VEGF receptor-2 attached to the Fc portion of IgG1. In preclinical studies, aflibercept has demonstrated a more favorable pharmacokinetic profile. Aflibercept has been evaluated in a Phase III study in combination with irinotecan-based chemotherapy in patients with metastatic CRC refractory to oxaliplatin-based chemotherapy. The results of the VELOUR study showed that the addition of aflibercept produced an advantage in both progression-free and overall survival.

Areas covered: In this review article, we will look over the preclinical and clinical development of aflibercept.

Expert opinion: In our opinion research is moving forward on a good path; we have seen the recent approval of aflibercept, and in the following years we might have newer standard treatment options among the latest compounds under development.     

Mavrilimumab,a human monoclonal GM-CSF receptor-α antibody for the management of rheumatoid arthritis: a novel approach to therapy

Introduction: Mavrilimumab, formerly known as CAM-3001, a GM-CSF receptor-α antibody, is the first human monoclonal antibody to be used in Phase II studies (2011) to modulate the innate immunity pathway targeting GM-CSF signaling in moderate rheumatoid arthritis (RA).

Areas covered: Analysis of available clinical trial data on GM-CSF receptor-α antibody and medical literature search using MEDLINE for molecular mechanisms of pathogenesis of RA and its treatment forms the basis of this expert opinion review. The mavrilimumab Phase II double blind, randomized, placebo-controlled ascending dose trial demonstrated statistically significant achievement of primary and secondary end points in patients with moderate RA. The trial demonstrated significant clinical benefit in the 100 mg mavrilimumab cohort compared to the placebo group.

Expert opinion: The novel molecular targeting mechanism of mavrilimumab together with its demonstrated clinical efficacy, tolerability and safety profile in Phase II clinical trials in moderate RA, suggests significant potential utility for this drug to induce clinical remission, reduce flares and improve morbidity and mortality in patients with RA.