The interventional effect of new drugs combined with the Stupp protocol on glioblastoma: A network meta-analysis

Methods behind oncolytic virus-based DC vaccines in cancer: Toward a multiphase combined treatment strategy for Glioblastoma (GBM) patients

Glioblastoma (GBM) remains an orphan cancer disease with poor outcome. Novel treatment strategies are needed. Immunotherapy has several modes of action. The addition of active specific immunotherapy with dendritic cell vaccines resulted in improved overall survival of patients. Integration of DC vaccination within the first-line combined treatment became a challenge, and immunogenic cell death immunotherapy during chemotherapy was introduced. We used a retrospective analysis using real world data to evaluate the complex combined treatment, which included individualized multimodal immunotherapy during and after standard of care, and which required adaptations during treatment, and found a further improvement of overall survival. We also discuss the use of real world data as evidence. Novel strategies to move the field of individualized multimodal immunotherapy forward for GBM patients are reviewed.

Efficacy and Safety of Bevacizumab Combined with Other Therapeutic Regimens for Treatment of Recurrent Glioblastoma: A Network Meta-analysis

BACKGROUND

Despite the fact that bevacizumab (Bev) has been approved to treat recurrent glioblastoma, patients have failed to demonstrate a significant overall survival (OS) advantage. In recent years, the advent of more Bev combination regimens seems to bring new hope for patients; nevertheless, there is still a lack of intuitive comparison among these therapies.

OBJECTIVE

To explore the efficacy and safety of various Bev combination regimens in patients with recurrent glioblastoma and to further explore the differences in the efficacy of each treatment in randomized controlled trials (RCTs) and nonrandomized controlled trials (non-RCTs).

METHODS

We comprehensively searched the PubMed, Cochrane Library, and OVID databases for relevant RCTs and non-RCTs of Bev in combined regimens for recurrent glioblastoma. The Cochrane quality assessment method was used to assess the quality of RCTs, and the Newcastle-Ottawa scale was used to assess the quality of non-RCTs. Excel software was used to extract data from the literature, and a network meta-analysis was performed using RevMan 5.3 and Stata 16 statistical software.

RESULTS

In patients with recurrent glioblastoma, the 6-month OS of patients receiving bevacizumab combination therapy was ranked from high to low as follows: Bev + rindopepimut, Bev + lomustine (CCNU), CCNU, tumor treating fields + Bev, Bev, Bev + irinotecan (Iri), Bev + temozolomide (TMZ), Bev + vorinostat, Bev + onartuzumab, Bev + dasatinib, Bev + carboplatin, Bev + trebananib, Bev + VB-111, TMZ, PCV, VB-111, and carboplatin. The 6-month progression-free survival from high to low was ranked as follows: Bev + CCNU, Bev + rindopepimut, Bev + dasatinib, Bev + vorinostat, Bev, Bev + Iri, Bev + TMZ, CCNU, Bev + carboplatin, TMZ, Bev + VB-111, PCV, Bev + trebananib, carboplatin, and VB-111. We compared the total incidence of serious adverse events (≥3) and found that Bev + vorinostat and Bev + trebananib were safer than Bev, while other regimens were not as safe as Bev. A descriptive analysis showed that Bev + rindopepimut also appeared to be safer than Bev. In subgroup analysis, among RCTs, Bev + CCNU therapy had the highest 6-month OS and 6-month progression-free survival. Among non-RCTs, Bev + Iri therapy showed the highest 6-month OS and good 6-month progression-free survival.

CONCLUSIONS

Both Bev + CCNU and Bev + rindopepimut could be considered as effective therapies for treating the recurrent glioblastoma according to the network meta-analysis results. Among them, Bev + rindopepimut therapy seems to be safer and more effective. Moreover, we found that Bev + Iri also appeared to be an effective therapy in a retrospective study.

Systematic review and network meta-analysis of the efficacy of existing treatments for patients with recurrent glioblastoma

Background

Despite advances in the treatment of cancers over the last years, treatment options for patients with recurrent glioblastoma (rGBM) remain limited with poor outcomes. Many regimens have been investigated in clinical trials; however, there is a lack of knowledge on comparative effectiveness. The aim of this systematic review is to provide an overview of existing treatment strategies and to estimate the relative efficacy of these regimens in terms of progression-free survival (PFS) and overall survival (OS).

Methods

We conducted a systematic review to identify randomized controlled trials (RCTs) investigating any treatment regimen in adult patients suffering from rGBM. Connected studies reporting at least one of our primary outcomes were included in a Bayesian network meta-analysis (NMA) estimating relative treatment effects.

Results

Forty RCTs fulfilled our inclusion criteria evaluating the efficacy of 38 drugs as mono- or combination therapy. Median OS ranged from 2.9 to 18.3 months; median PFS ranged from 0.7 to 6 months. We performed an NMA including 24 treatments that were connected within a large evidence network. Our NMA indicated improvement in PFS with most bevacizumab (BV)-based regimens compared to other regimens. We did not find any differences in OS between treatments.

Conclusion

This systematic review provides a comprehensive overview of existing treatment options for rGBM. The NMA provides relative effects for many of these treatment regimens, which have not been directly compared in RCTs. Overall, outcomes for patients with rGBM remain poor across all treatment options, highlighting the need for innovative treatment options.

Optimal treatment strategy for adult patients with newly diagnosed glioblastoma: a systematic review and network meta-analysis

To compare the efficacy and safety of treatments based on the Stupp protocol for adult patients with newly diagnosed glioblastoma and to determine the optimal treatment option for patients with different O-6-methylguanine-DNA methyltransferase (MGMT) promoter methylation statuses. We estimated hazard ratios (HRs) for overall survival (OS) and odds ratios (ORs) for adverse events of grade 3 or higher (AEs ≥ 3). Twenty-one randomized controlled trials involving 6478 patients treated with 21 different treatment strategies were included. Results of the pooled HRs indicated tumor-treating fields (TTF) combined with the Stupp protocol resulted in the most favorable OS for patients with and without MGMT promoter methylation. Subgroup analyses by the two MGMT promoter statuses indicated that lomustine-temozolomide plus radiotherapy or TTF combination therapy was associated with the best OS for patients with methylated MGMT promoter (HR, 1.03; 95% credible interval [CI], 0.54-1.97), and standard cilengitide combination therapy or TTF combination treatment was associated with the best OS for patients with unmethylated MGMT promoter (HR, 1.05; 95% CI, 0.67-1.64). Regarding AEs ≥ 3, there were no significant differences in pooled ORs. However, Bayesian ranking profiles that demonstrated intensive cilengitide combination therapy and TTF combination therapy have a similar possibility to cause the least toxicity. These results indicated that TTF combination therapy was associated with increased survival, irrespective of the MGMT promoter methylation status, and a relatively tolerated safety profile compared with other combination treatments. The optimal treatment option for glioblastoma patients with different MGMT promoter methylation statuses was different.

Personalized neoantigen vaccines: a glimmer of hope for glioblastoma

INTRODUCTION

Glioblastoma multiforme (GBM) is the most prevalent primary brain tumor. In spite of the rigorous multimodal treatment involving surgery and radiochemotherapy, GBM has a dismal prognosis and rapid relapsing potential. Hence, search for novel therapeutic agents still continues. Neoantigens are the tumor-specific antigens which arise due to somatic mutations in the tumor genome. In recent years, personalized vaccine approach targeting neoantigens has been explored widely in cancer immunotherapy and several efforts have also been made to revolutionize the immunotherapy of cold tumors such as GBM using neoantigen targeted vaccines.

AREAS COVERED

In this review, we discuss the clinical application of personalized neoantigen targeted vaccine strategy in GBM immunotherapy. While discussing this strategy, we brief about the current challenges faced in GBM treatment by the novel immunotherapeutics.

EXPERT OPINION

To date, very few vaccines developed for GBM have reached till phase III clinical development. Early-phase clinical trials of GBM neoantigen vaccines have shown promising clinical outcomes and therefore, its rapid clinical development is warranted. Advent of newer and faster techniques such as next-generation sequencing will drive the faster clinical development of multiplex neoantigen vaccines and hence, increase in the clinical trials is expected.

The Small Molecule Ephrin Receptor Inhibitor, GLPG1790, Reduces Renewal Capabilities of Cancer Stem Cells, Showing Anti-Tumour Efficacy on Preclinical Glioblastoma Models

Therapies against glioblastoma (GBM) show a high percentage of failure associated with the survival of glioma stem cells (GSCs) that repopulate treated tumours. Forced differentiation of GSCs is a promising new approach in cancer treatment. Erythropoietin-producing hepatocellular (Eph) receptors drive tumourigenicity and stemness in GBM. We tested GLPG1790, a first small molecule with inhibition activity versus inhibitor of various Eph receptor kinases, in preclinical GBM models using in vitro and in vivo assays. GLPG1790 rapidly and persistently inhibited Ephrin-A1-mediated phosphorylation of Tyr⁵⁸⁸ and Ser⁸⁹⁷, completely blocking EphA2 receptor signalling. Similarly, this compound blocks the ephrin B2-mediated EphA3 and EphB4 tyrosine phosphorylation. This resulted in anti-glioma effects. GLPG1790 down-modulated the expression of mesenchymal markers CD44, Sox2, nestin, octamer-binding transcription factor 3/4 (Oct3/4), Nanog, CD90, and CD105, and up-regulated that of glial fibrillary acidic protein (GFAP) and pro-neural/neuronal markers, βIII tubulin, and neurofilaments. GLPG1790 reduced tumour growth in vivo. These effects were larger compared to radiation therapy (RT; U251 and T98G xenografts) and smaller than those of temozolomide (TMZ; U251 and U87MG cell models). By contrast, GLPG1790 showed effects that were higher than Radiotherapy (RT) and similar to Temozolomide (TMZ) in orthotopic U87MG and CSCs-5 models in terms of disease-free survival (DFS) and overall survival (OS). Further experiments were necessary to study possible interactions with radio- and chemotherapy. GLPG1790 demonstrated anti-tumor effects regulating both the differentiative status of Glioma Initiating Cells (GICs) and the quality of tumor microenvironment, translating into efficacy in aggressive GBM mouse models. Significant common molecular targets to radio and chemo therapy supported the combination use of GLPG1790 in ameliorative antiglioma therapy.

Non-genomic Actions of Thyroid Hormones Regulate the Growth and Angiogenesis of T Cell Lymphomas

T-cell lymphomas (TCL) are a heterogeneous group of aggressive clinical lymphoproliferative disorders with considerable clinical, morphological, immunophenotypic, and genetic variation, including ~10-15% of all lymphoid neoplasms. Several evidences indicate an important role of the non-neoplastic microenvironment in promoting both tumor growth and dissemination in T cell malignancies. Thus, dysregulation of integrin expression and activity is associated with TCL survival and proliferation. We found that thyroid hormones acting via the integrin αvβ3 receptor are crucial factors in tumor microenvironment (TME) affecting the pathophysiology of TCL cells. Specifically, TH-activated αvβ3 integrin signaling promoted TCL proliferation and induced and an angiogenic program via the up-regulation of the vascular endothelial growth factor (VEGF). This was observed both on different TCL cell lines representing the different subtypes of human hematological malignancy, and in preclinical models of TCL tumors xenotransplanted in immunodeficient mice as well. Moreover, development of solid tumors by inoculation of murine TCLs in syngeneic hyperthyroid mice, showed increased tumor growth along with increased expression of cell cycle regulators. The genomic or pharmacological inhibition of integrin αvβ3 decreased VEGF production, induced TCL cell death and decreased in vivo tumor growth and angiogenesis. Here, we review the non-genomic actions of THs on TCL regulation and their contribution to TCL development and evolution. These actions not only provide novel new insights on the endocrine modulation of TCL, but also provide a potential molecular target for its treatment.

Comparative effect of immunotherapy and standard therapy in patients with high grade glioma: a meta-analysis of published clinical trials

Immunotherapy holds great promise in the treatment of high grade glioma (HGG). We performed a comprehensive meta-analysis of clinical trials involving dendritic cell (DC) therapy and viral therapy (VT) for the treatment of HGG, in order to assess their clinical impact in comparison to standard treatments in terms of overall survival (OS) and progression-free survival (PFS). To our knowledge, this is the first meta-analysis to evaluate VT for the treatment of HGG, allowing comparison of different immunotherapeutic approaches. Thirteen eligible studies of 1043 cases were included in the meta-analysis. For DC vaccination, in terms of OS, both newly diagnosed patients (HR, 0.65) and patients who suffered from recurrent HGGs (HR = 0.63) presented markedly improved results compared to the control groups. PFS was also improved (HR = 0.49) but was not statistically significant (p = 0.1). A slight improvement was observed for newly diagnosed patients receiving VT in terms of OS (HR = 0.88) while PFS was inferior for patients in the experimental arm (HR = 1.16). Our results show that DC therapy greatly improves OS for patients with both newly diagnosed and recurrent HGGs. VT, however, did not provide any statistically significant improvements in terms of OS and PFS for patients with newly diagnosed HGGs.