Monoclonal antibodies currently in Phase II and III trials for multiple myeloma

Introduction: Despite the introduction of novel agents, such as thalidomide, lenalidomide and bortezomib, multiple myeloma (MM) remains an incurable disease and new therapies are needed. mAbs are a new promising anticancer treatment option.

Areas covered: This review will focus on mAbs that are currently under evaluation in Phase II and III clinical trials, as single agent and in combination with established treatment options.

Expert opinion: mAbs are a new strategy against MM, and they have demonstrated encouraging results in preclinical models. mAbs have a relatively benign side-effect profile and work synergistically with traditional chemotherapies and with immunomodulatory drugs and proteasome inhibitors.     

CD38 as an immunotherapeutic target in multiple myeloma

ABSTRACT

Introduction: Multiple myeloma (MM) is a currently incurable hematologic tumor with heterogeneous clinical behavior and prognosis. During the last years, survival improved due to a better understanding of MM biology and the development of novel drugs, although it still remains unsatisfactory in many cases: new drugs and treatment strategies are needed. CD38 is uniformly expressed at high levels on MM cells and, to a lesser extent, on the surface of normal hematopoietic and non-hematopoietic cells, making this molecule an interesting target for immunotherapeutic approaches.

Areas covered: This review discusses the preclinical and clinical experience on different immunotherapeutic agents targeting CD38 in MM.

Expert commentary: Monoclonal antibodies (mAbs) targeting CD38 are currently changing the treatment scenario in MM, allowing physicians to reach unprecedented results, especially when anti-CD38 mAbs are used in combination with consolidated MM treatments. Other immunotherapies targeting CD38 – such as conjugated anti-CD38 mAbs, bispecific antibodies stimulating T cells to eliminate CD38+ MM cells, and CD38-specific chimeric antigen receptor T cells – are interesting strategies, currently at earlier developmental stages.     

Allogeneic stem cell transplantation in multiple myeloma: immunotherapy and new drugs

Introduction: Autologous (auto) stem cell transplantation (SCT) and the development of new drugs have improved the survival of multiple myeloma (MM) patients. By contrast, though potentially curative, the use of allogeneic (allo)-SCT is controversial.

Areas covered: A review has been conducted to examine the current evidence for the use of allo-SCT in MM. We have examined novel cell therapies that may be exploited to induce myeloma-specific immune responses including the new promising frontier of chimeric antigen receptor (CAR)-T and -natural killer (NK) cells.

Expert opinion: One of the major controversies facing researchers in exploring the allo approach is the remarkable recent treatment improvement observed with second- and third-generation proteasome inhibitors and immunomodulatory drugs, monoclonal antibodies and deacetylase inhibitors. Despite these great advances, the disease remains to be incurable and allo-SCT may still play a role in the cure of MM. We think that allo-SCT conserves a role in MM and its curative potential in high-risk patients should be explored in the setting of control clinical trials. Novel cell therapies such as CAR technologies may open new avenues of research toward a potential cure. Data from currently ongoing prospective studies will be helpful to clarify pending clinical questions.     

Ofatumumab,a human anti-CD20 monoclonal antibody

Importance of the field: Since relapse of chronic lymphocytic leukemia (CLL), and refractoriness to treatment following relapse, is inevitable after initial treatment, development of novel treatment strategies is necessary.

Areas covered in this review: CD20 as a therapeutic target for CLL, successes and limitations of current anti-CD20 monoclonal antibody (mAb) therapy, and implications of preclinical and clinical developments of novel alternatives, including ofatumumab, that may enhance anti-CD20 mAb therapy are reviewed. The literature reviewed encompasses papers and congress abstracts from the past 13 years.

What the reader will gain: While rituximab combined with chemotherapy has considerably improved outcomes for some but not all CLL patients, single-agent use is limited in relapsed/refractory CLL. Novel anti-CD20 mAbs in development, such as ofatumumab, may bypass some limitations by virtue of alternative epitope binding and modified effector functions. Ofatumumab induces significant complement-dependent cell lysis in vitro, particularly in cells with low CD20 expression. The FDA recently approved ofatumumab for treatment of CLL refractory to fludarabine and alemtuzumab.

Take home message: CD20-targetting chemoimmunotherapeutic options have advanced treatment of CLL. Results for single-agent ofatumumab and other new CD20 mAbs, in different lines of therapy and in combination with chemotherapy, will guide optimal use of these alternative therapies for B-cell malignancies.     

Galiximab: a review

Importance of the field: A significant number of patients relapse or do not respond to rituximab due to intrinsic or acquired resistance. Hence, mAbs targeting other cell surface antigens on B-cell lymphomas are being studied. CD80 is a glycoprotein expressed on Hodgkin's lymphoma, mature B-cell lymphomas and immunoeffector cells which may have T-regulatory, in addition to direct antitumor activity. CD80 serves as an attractive target in the continued development of mAbs against lymphoma.

Areas covered in this review: Preclinical studies with galiximab, an anti-CD80 primatized mAb, have been encouraging and have demonstrated antitumor activity against various B-cell lymphoma models, both as a single agent as well as in combination with rituximab. Data were reviewed from a PubMed literature search from 1975 to 2009 and also included a review of abstracts from published proceedings of annual meetings from the American Society of Hematology and International Conference of Malignant Lymphoma, Lugano.

What the reader will gain: Readers will gain a better understanding of mechanisms of action (both documented and proposed) of galiximab. An update of currently available clinical data will be presented.

Take home message: Data from completed clinical trials are promising and galiximab is being studied in both upfront and relapsed settings with the potential of being incorporated into the future treatment of B-cell lymphoma.     

B cell maturation antigen (BCMA)-based immunotherapy for multiple myeloma

ABSTRACT

Introduction: B cell maturation antigen (BCMA) contributes to MM pathophysiology and is a target antigen for novel MM immunotherapy. Complete responses have been observed in heavily pretreated MM patients after treatment with BCMA antibody-drug conjugates (ADC), chimeric antigen receptor T, and bi-specific T cell engagers (BiTE®). These and other innovative BCMA-targeted therapies transform the treatment landscape and patient outcome in MM.

Areas covered: The immunobiological rationale for targeting BCMA in MM is followed by key preclinical studies and available clinical data on efficacy and safety of therapies targeting BCMA from recent phase I/II studies.

Expert opinion: BCMA is the most selective MM target antigen, and BCMA-targeted approaches have achieved high responses even in relapse and refractory MM as a monotherapy. Long-term follow-up and correlative studies using immuno-phenotyping and -sequencing will delineate mechanisms of overcoming the immunosuppressive MM bone marrow microenvironment to mediate additive or synergistic anti-MM cytotoxicity. Moreover, they will delineate cellular and molecular events underlying the development of resistance underlying relapse of disease. Most importantly, targeted BCMA-based immunotherapies used earlier in the disease course and in combination (adoptive T cell therapy, mAbs/ADCs, checkpoint and cytokine blockade, and vaccines) have great promise to achieve long-term disease control and potential cure.     

HER2 as a target for breast cancer therapy

Importance of the field: Differential levels of HER2 expression in normal versus HER2-overexpressing breast carcinomas, together with the demonstration of a key role for HER2 in tumor progression, make HER2 an ideal target for specific therapeutic approaches.

Areas covered in this review: This review considers the clinical value of trastuzumab and lapatinib, the two HER2-targeted therapies approved for clinical practice. References were chosen by searching the PubMed and MEDLINE datasets using as search term: ‘HER2’, in association with ‘prognosis’, ‘response’, ‘trastuzumab’, ‘lapatinib’ and ‘resistance’.

What the reader will gain: This review deals with HER2 as a target for breast carcinoma treatment, focusing on anti-HER2 therapies used in clinical practice, their merits and shortcomings.

Take home message: The benefit of anti-HER2 therapies demonstrated in clinical trials indicates that HER2 is, to date, one of the most promising molecules for targeted therapy. Nevertheless, since tumor cells utilizing alternative growth signaling pathways through transmembrane receptors as well as intracellular signaling transduction molecules can bypass HER2 blockade, a future ambitious aim is the successful combination of anti-HER2 strategies with drugs directed to molecules that contribute to anti-HER2 resistance.     

Biological therapies for the treatment of cutaneous wounds: Phase III and launched therapies

Introduction: Normal wound healing mechanisms can be overwhelmed in the setting of complex acute and chronic tissue injury. Biological therapies are designed to augment and/or restore the body's natural wound healing abilities. There are a variety of available and emerging technologies utilizing this approach that have demonstrated the ability to augment wound healing.

Areas covered: In this review, the clinical data on launched and emerging biological therapies for wound healing applications are summarized. The methodologies discussed include biological skin equivalents, growth factors/small molecules and stem cell-based therapies.

Expert opinion: While many products possess convincing clinical data demonstrating their efficacy in comparison to standard treatment options, more robust, controlled studies are needed to determine the relative value among established and emerging biological therapies. Future bioengineering and stem cell-based approaches are of particular interest due to the simultaneous correction of multiple deficiencies present in the nonhealing wound.     

Inhibiting the inhibitors: evaluating agents targeting cancer immunosuppression

Importance of the field: Immunotherapy of cancer has not improved disease-free or overall patient survival. The lack of concordance between immunological and clinical responses in cancer immunotherapy trials is thought to result from the pervasive presence of tumor-driven immune suppression that allows tumor to escape and that has not been adequately targeted by current therapies.

Areas covered in this review: Because multiple mechanisms of tumor induced suppression have been identified and shown to contribute to tumor escape, the opportunity arises to interfere with these mechanisms. A range of known tumor-derived inhibitors can now be blocked or neutralized by biologic or metabolic agents. Used alone or in combination with each other or with conventional cancer therapies, these agents offer novel therapeutic strategies for the control of tumor escape.

What the reader will gain: This review deals with currently available inhibitors for counteracting tumor immune escape. The restoration of effective anti-tumor immunity in patients with cancer will require new approaches aiming at: i) protection of immune cells from adverse effects of myeloid-derived suppressor cells, regulatory T cells or inhibitory factors thus enhancing effector functions; and ii) prolonging survival of central memory T cells, thus ensuring long-term protection.

Take home message: Inhibitors of mechanisms responsible for tumor escape could restore anti-tumor immune responses in patients with cancer.     

Ustekinumab: targeting the IL-17 pathway to improve outcomes in psoriatic arthritis

ABSTRACT

Introduction: Autologous Stem Cell Transplantation (ASCT) represents the standard treatment in eligible “de-novo” multiple myeloma (MM) patients.

Areas covered: ASCT may be single or tandem, and a single ASCT can be followed by an allogeneic (Allo)-SCT. A systematic review has been conducted to examine the current evidence for the efficacy of using a tandem transplant strategy in MM.

Expert opinion: A tandem ASCT approach should be considered for all patients, although the benefit from the second ASCT in patients who are in complete remission or experience a very good partial response should be answered in a clinical trial. Recent results with the new induction regimens indicate that there is a role for tandem ASCT in the presence of adverse cytogenetic abnormalities. Planned AlloSCT after ASCT has not been found to be superior in the majority of studies and is not recommended outside of a clinical trial. However, single or tandem ASCT are both appropriate options and participation in prospective clinical trials should be encouraged to resolve the debate in the era of novel agents for MM.     

Anti-CD37 antibodies for chronic lymphocytic leukemia

Introduction: Immunotherapy using mAbs is a safe and effective method for the treatment of chronic lymphocytic leukemia (CLL) and other lymphoid malignancies. In recent years, mAbs based on selective B-cell depletion – rituximab, ofatumumab and obinutuzumab – have been approved for use in CLL therapy. More recently, CD37, a member of the tetraspanin superfamily of cell surface antigens, has been considered as a target for B-cell malignancies.

Areas covered: The results of preclinical and early clinical studies suggest that in patients with CLL, newer anti-CD37 agents, otlertuzumab (formerly known as TRU-016), BI 836826, IMGN529 and ¹⁷⁷Lu-tetulomab can be useful in the treatment of this disease.

Expert opinion: CD37 may offer advantages over CD20 as a target for CLL cells. It is selectively expressed on normal mature B cells and by most B-cell malignancies. Anti-CD37 antibodies may be useful for patients resistant or refractory to anti-CD20 mAb therapy or relapsing after such treatment. The development of these agents into a clinically useful therapy for CLL is probably many years away and will be followed with great interest by laboratory investigators and clinicians.     

PMN-MDSC and arginase are increased in myeloma and may contribute to resistance to therapy

Objectives: Despite improvement in overall response due to the introduction of the first-in-class proteasome inhibitor bortezomib (btz), multiple myeloma (MM) is still an incurable disease due to the immune-suppressive bone marrow (BM) environment. Thus, the authors aimed to identify the role of CD11b⁺CD15⁺CD14^?HLA-DR^? granulocytic-like myeloid-derived suppressor cells (PMN-MDSC) in MM patients treated up-front with novel agents.

Methods: In MM cell lines and primary cells derived by patients affected by MGUS and MM, we investigated sensitivity to bortezomib and lenalidomide in presence of Arg-1 and PMN-MDSC.

Results: The authors found that PMN-MDSC and their function through increased arginase-1 (Arg-1) are associated with MM progression. When the authors assessed cell viability of the human myeloma cell lines MM1.s, OPM2 and U266 treated with 5–20 nM btz for 24 h in PMN-MDSC conditioned media, they disclosed that amount of Arg-1 and Arg-1 inhibition could affect btz sensitivity in-vitro.

PMN-MDSC and Arg-1 were increased in peripheral blood of newly diagnosed MM patients compared to healthy subjects. PMN-MDSC and arginase were reduced after exposure to lenalidomide-based regimen but increased after btz-based treatment.

Conclusion: In MM, Arg-1 is mainly expressed by PMN-MDSC. PMN-MDSC and Arg-1 are reduced in vivo after lenalidomide but not bortezomib treatment.     

树突状细胞疫苗治疗多发性骨髓瘤的研究进展

近年来多发性骨髓瘤的发病率不断上升,但目前对于多发性骨髓瘤仍然没有很好的治疗方法。树突状细胞是一类抗原呈递细胞,具有启动和调控免疫反应的能力。利用肿瘤抗原冲击树突状细胞的免疫治疗策略已被证明是安全的并且对许多肿瘤具有一定的治疗效果。本文综述了多发性骨髓瘤相关的各种肿瘤抗原类型及树突状细胞免疫治疗多发性骨髓瘤的临床实验,并且分析了树突状细胞免疫治疗在未来实验研究方面的前景。     

Assessment and management of cytokine release syndrome and neurotoxicity following CD19 CAR-T cell therapy

ABSTRACT

Introduction: The success of CD19 chimeric antigen receptor (CAR)-T cell therapy for treatment of CD19 positive malignancies has led to the FDA approval of two CD19 CAR-T cell products, tisagenlecleucel and axicabtagene ciloleucel, and ongoing clinical trials of new products. Cytokine release syndrome (CRS) and neurotoxicity are common toxicities associated with CD19 CAR-T cell therapies.

Areas covered: This review will discuss CRS and neurotoxicity associated with CD19 CAR-T cell therapies, including clinical presentation, risk factors, pathophysiology, and therapeutic or prophylactic interventions.

Expert opinion: In conjunction with improved understanding of the pathophysiology of CRS and neurotoxicity, we expect that the recent development of consensus guidelines for the evaluation of these toxicities will enhance management of patients undergoing CD19 CAR-T cell therapies.     

Monoclonal antibodies for the treatment of osteoarthritis

ABSTRACT

Introduction: Osteoarthritis (OA) is a multifactorial chronic joint disease, and so far, there are no approved disease-modifying anti-OA drugs (DMOADs). There is an urgent need to develop therapies for different phenotypes of OA. Monoclonal antibodies (mAb) may slow structural progression, control inflammation and relieve pain, and thus have the potential to be DMOADs.

Areas covered: In this review, the authors searched the literature on PubMed, EMBASE and the Cochrane Library using keywords, including mAbs, biological agents, OA and osteoarthritis, electronically up to May 2016. They also included abstracts of international conferences. Furthermore, they reviewed experimental and clinical studies of various mAbs targeting different pathological mechanisms of OA, including ADAMTS, Interleukine-1, tumour necrosis factor, never growth factor and vascular endothelial growth factor.

Expert opinion: MAbs for the treatment of OA are under intense investigation and the results for some mAbs (e.g., anti-nerve growth factor mAbs, anti- vascular endothelial growth factor mAbs) are promising. The authors believe that mAb therapy can be a targeted therapeutic approach for the treatment of OA. Future clinical trials are required to evaluate the therapeutic efficacy of these agents by the appropriate selection of specific phenotype for targeted therapy based on the mechanism of drug action.     

Anti-EGFR and antiangiogenic monoclonal antibodies in metastatic non-small-cell lung cancer

ABSTRACT

Introduction: In recent years, several clinical trials have evaluated the efficacy and safety of biological therapies in lung cancer. Epidermal growth factor receptor (EGFR) and the axis vascular endothelial growth factor receptor (VEGF/VEGFR) are targeted by small molecules and monoclonal antibodies (mAbs), especially in non-squamous non-small-cell lung cancer (NSCLC).

Areas covered: The current state of the art of anti-EGFR and antiangiogenic monoclonal antibodies in metastatic NSCLC is reviewed and discussed.

Expert opinion: Bevacizumab and cetuximab are the most studied mAbs in NSCLC, but only bevacizumab is in clinical practice in the first-line setting. Necitumumab is a new anti-EGFR monoclonal antibody that improves survival when combined to cisplatin/gemcitabine chemotherapy and has been approved in first-line advanced NSCLC. Ramucirumab, an antiangiogenic drug binding with high affinity to VEGFR-2, improves the results of chemotherapy alone when administered with docetaxel and has been approved in second-line setting. Moreover, the novel combination of bevacizumab and erlotinib is very promising for the treatment of patients with NSCLC harbouring EGFR mutations. The association of antiangiogenic mAbs and immunotherapy is under investigation too.     

Pharmacotherapy and interventional treatments for secondary hyperparathyroidism: current therapy and future challenges

Importance of the field: Chronic kidney disease is frequently complicated by secondary hyperparathyroidism, which causes bone disease and vascular calcification, leading to increased risk of morbidity and mortality.

Areas covered in this review: This review covers treatment options for secondary hyperparathyroidism in patients receiving dialysis, particularly focusing on active vitamin D derivatives, calcimimetics and direct injection therapy into parathyroid glands. In addition, the potential of gene therapy is also described.

What the reader will gain: The reader will gain a comprehensive review of the effectiveness and role of available therapies for patients with secondary hyperparathyroidism, as well as the results of observational studies that address the effect of these treatments on clinical outcomes.

Take home message: Treatment with active vitamin D derivatives and calcimimetics allows adequate control of secondary hyperparathyroidism, which it is hoped will translate into improved clinical outcomes. These treatments appear to be effective even in patients with advanced disease, but patients who develop resistance to therapy should undergo parathyroid intervention, such as surgical parathyroidectomy and direct injection therapy. Gene therapy is not applicable to humans at present, but they will help clarify the molecular pathogenesis of secondary hyperparathyroidism.     

Gene therapy as future treatment of erectile dysfunction

Importance of the field: Erectile dysfunction (ED) is a major men's health problem. Although the high success rate of treating ED by phosphodiesterase 5 (PDE5) inhibitors has been reported, there are a significant number of ED patients who do not respond to currently available treatment modalities.

Areas covered in this review: To elucidate the current status of gene therapy applications for ED, gene therapy approaches for ED treatment are reviewed.

What the reader will gain: Gene therapy strategies that can enhance nitric oxide (NO) production or NO-mediated signaling pathways, growth factor-mediated nerve regeneration or K⁺ channel activity in the smooth muscle could be promising approaches for the treatment of ED. Although the majority of gene therapy studies are still in the preclinical phase, the first clinical trial using non-viral gene transfer of Ca²⁺-activated, large-conductance K⁺ channels into the corpus cavernosum of ED patients showed positive results.

Take home message: Gene therapy represents an exciting future treatment option for ED, especially for people with severe ED unresponsive to current first-line therapies such as PDE5 inhibitors although the long-term safety of both viral and non-viral gene therapies should be established.     

New era of biologic therapeutics in atopic dermatitis

Introduction: Atopic dermatitis (AD) is a common inflammatory skin disease regulated by genetic and environmental factors. Both skin barrier defects and aberrant immune responses are believed to drive cutaneous inflammation in AD. Existing therapies rely largely on allergen avoidance, emollients and topical and systemic immune-suppressants, some with significant toxicity and transient efficacy; no specific targeted therapies are in clinical use today. As our specific understanding of the immune and molecular pathways that cause different subsets of AD increases, a variety of experimental agents, particularly biologic agents that target pathogenic molecules bring the promise of safe and effective therapeutics for long-term use.

Areas covered: This paper discusses the molecular pathways characterizing AD, the contributions of barrier and immune abnormalities to its pathogenesis, and development of new treatments that target key molecules in these pathways. In this review, we will discuss a variety of biologic therapies that are in development or in clinical trials for AD, perhaps revolutionizing treatment of this disease.

Expert opinion: Biologic agents in moderate to severe AD offer promise for controlling a disease that currently lacks good and safe therapeutics posing a large unmet need. Unfortunately, existing treatments for AD aim to decrease cutaneous inflammation, but are not specific for the pathways driving this disease. An increasing understanding of the immune mechanisms underlying AD brings the promise of narrow targeted therapies as has occurred for psoriasis, another inflammatory skin disease, for which specific biologic agents have been demonstrated to both control the disease and prevent occurrence of new skin lesions. Although no biologic is yet approved for AD, these are exciting times for active therapeutic development in AD that might lead to revolutionary therapeutics for this disease.