Phase II study of single-agent bevacizumab in Japanese patients with recurrent malignant glioma

Efficacy of radioactive hypoxia-targeting therapeutic agent 64Cu-ATSM on recurrent malignant glioma: a study protocol for a phase-III, investigator-sponsored, randomized controlled trial

Previously, we conducted the phase I study of 64Cu-ATSM, which is Cu-diacetyl-bis (N4-methylthiosemicarbazone) radiolabeled with Cu-64, for patients with brain tumors and determined the maximum tolerated dose. We started a subsequent multicenter, randomized, open-label phase III study to evaluate the efficacy of 64Cu-ATSM as an investigator-initiated registration-directed trial for recurrent or residual malignant glioma (protocol No. NCCH2301, STEP-64). Patients will be randomized to either the control or study arm (64Cu-ATSM). A large-scale randomized trial seems difficult to perform for patients with brain tumors because of small sample sizes. Therefore, we designed a small randomized trial with 56 patients. Furthermore, as a pragmatic approach in the control arm, physicians can choose treatments depending on the patient's condition among the clinically available options, where the drugs used are not regarded as investigational. The trial was registered in the Japan Registry of Clinical Trials as jRCT2031240090.

Treatment mechanism and research progress of bevacizumab for glioblastoma

Hypervascularization is a notable pathological hallmark of glioblastoma (GBM). Bevacizumab (Bev) remains the sole antiangiogenic agent approved by the U.S. Food and Drug Administration (FDA) for GBM treatment. The approval for this indication was supported by several phase II studies demonstrating that Bev significantly improved progression-free survival and the best imaging response in patients with recurrent GBM. Three large phase III randomized controlled trials reported that Bev did not significantly extend overall survival (OS). Nevertheless, Bev has been shown to delay the deterioration of patients' quality of life by postponing tumor progression. This review synthesizes findings from recent investigations exploring Bev in combination with targeted therapies, immunotherapy, or reirradiation. Additionally, this review discusses dosing regimens, administration, treatment failure patterns, third-line therapeutic applications, and prognostic markers of Bev. By synthesizing current evidence, this review aims to inform clinical decision-making for neuro-oncology clinicians.

Outcomes of awake surgery for recurrent glioblastoma: A single-institution retrospective analysis

BACKGROUND

Awake surgery facilitates maximal safe resection of brain tissue in cases of glioma, but its effectiveness for recurrent glioblastoma (GBM) remains unestablished. In this study, we investigate the safety, success rate of mapping, and surgical outcomes of awake surgery for recurrent GBM.

METHODS

This study included glioma cases that underwent awake surgery at our hospital between March 2010 and February 2023 and met the following criteria: (1) cases with a pathologic diagnosis of glioblastoma or astrocytoma, isocitrate dehydrogenase-mutant, WHO grade 4 at recurrence, and (2) cases in which this was the second surgery in the course of treatment. We retrospectively analyzed the clinical features, mapping response, resection rate, postoperative complications, overall survival (OS), and progression-free survival (PFS).

RESULTS

Forty-one cases were analyzed. The median age was 47 years, and 24 patients (58.5 %) were male. Awake mapping was successfully completed in 35 cases (85.4 %). A positive response to mapping was observed in 20 cases (48.8 %), which limited resection in 15 cases (36.6 %). The extent of resection was gross total resection in 20 cases (48.8 %), subtotal resection in 11 cases (26.8 %), partial resection in 8 cases (19.5 %), and biopsy in 2 cases (4.9 %). Acute-phase neurological deficits developed in 10 cases (24.4 %), but sequelae or symptom exacerbations were observed in 2 cases (4.9 %). The median post-recurrence OS and PFS were 18.7 months and 7.2 months, respectively.

CONCLUSIONS

Awake mapping for recurrent GBM demonstrated a low complication rate and facilitated tumor resection without exacerbating neurological symptoms. Awake surgery for recurrent GBM may contribute to prolonged survival.

Characteristics of adverse reactions of three anti-glioma drugs in WHO-VigiAccess

Introduction

Antitumor medications such as Avastin, Berubicin, and Temozolomide have fundamentally transformed the treatment landscape for gliomas by exhibiting potent pharmacological effects on both high-grade and low-grade gliomas. This study aims to determine which anti-glioma medication presents the lowest risk for personalized use in clinical patients by assessing the adverse drug reactions (ADRs) associated with these medications as reported in the World Health Organization (WHO) VigiAcess database, and by comparing the characteristics of adverse responses among the three drugs.

Methods

This investigation employs a retrospective descriptive analysis method. We compiled ADR reports for three commercially available anti-glioma medications from WHO-VigiAccess, gathering data on the disease systems and symptoms associated with ADRs, as well as the age, gender, and geographic characteristics of the patients represented in the reports. To provide a reference for clinical treatment, we analyzed the similarities and differences in the adverse reactions of the three medications by calculating the proportion of adverse reactions recorded for each drug.

Results

A total of 132,471 adverse events (AEs) associated with three anti-glioma drugs were reported in VigiAccess. The analysis revealed that the ten most frequently reported AEs included bone marrow suppression, myalgia, leukopenia, thrombocytopenia, nausea, vomiting, death, rhabdomyolysis, disease progression, and a decrease in neutrophil count. The five most common categories of AEs related to anti-glioma drugs were blood and lymphatic system diseases (20,233 cases, 15.2%), general disorders and administration site conditions (26,973 cases, 20.3%), gastrointestinal dysfunction (22,061 cases, 16.7%), necessitating further investigations (18,285 cases, 13.8%), and musculoskeletal and connective tissue diseases (30,695 cases, 23.1%). Notably, the adverse events associated with Avastin were more pronounced in the category of musculoskeletal and connective tissue diseases compared to the other two drugs. Furthermore, Berubicin exhibited a particularly high proportion of blood and lymphatic system disease AEs, reaching 45.6%, which was significantly greater than those observed for the other two drugs.

Conclusion

There is limited correlation between antineoplastic medications and ADRs. Current comparative observational studies indicate that these inhibitors are associated with both common and specific adverse effects documented in the ADR reports submitted to the World Health Organization (WHO).

Re-irradiation combined with bevacizumab for recurrent glioblastoma beyond bevacizumab failure: survival outcomes and prognostic factors

The combination of re-irradiation and bevacizumab has emerged as a potential therapeutic strategy for patients experiencing their first glioblastoma multiforme (GBM) recurrence. This study aims to assess the effectiveness of the re-irradiation and bevacizumab combination in treating second-progression GBM patients who are resistant to bevacizumab monotherapy. This retrospective study enrolled 64 patients who developed a second progression after single-agent bevacizumab therapy. The patients were divided into two groups: 35 underwent best supportive care (none-ReRT group), and 29 received bevacizumab and re-irradiation (ReRT group). The study measured the overall survival time after bevacizumab failure (OST-BF) and re-irradiation (OST-RT). Statistical tests were used to compare categorical variables, evaluate the difference in recurrence patterns between the two groups, and identify optimal cutoff points for re-irradiation volume. The results of the Kaplan-Meier survival analysis indicated that the re-irradiation (ReRT) group experienced a significantly higher survival rate and longer median survival time than the non-ReRT group. The median OST-BF and OST-RT were 14.5 months and 8.8 months, respectively, for the ReRT group, while the OST-BF for the none-ReRT group was 3.9 months (p < 0.001). The multivariable analysis identified the re-irradiation target volume as a significant factor for OST-RT. Moreover, the re-irradiation target volume exhibited excellent discriminatory ability in the area under the curve (AUC) analysis, with an optimal cutoff point of greater than 27.58 ml. These findings suggest that incorporating re-irradiation with bevacizumab therapy may be a promising treatment strategy for patients with recurrent GBM resistant to bevacizumab monotherapy. The re-irradiation target volume may serve as a valuable selection factor in determining which patients with recurrent GBM are likely to benefit from the combined re-irradiation and bevacizumab treatment modality.

Venous Thromboembolism in Cancer Patients Undergoing Chemotherapy: A Systematic Review and Meta-Analysis

Objective: Venous thromboembolism (VTE) is a life-threatening complication that may exacerbate cancer prognosis. Whilst some studies indicate an increased risk of VTE in cancer patients undergoing chemotherapy, the prevalence estimates on the pooled prevalence of VTE in cancer patients undergoing chemotherapy are not known. This study aims to calculate the pooled prevalence of VTE in chemotherapy-treated cancer patients. Methods: Studies on VTE occurrence in cancer patients undergoing chemotherapy were retrieved after database search. The terms used included “cancer”, “chemotherapy”, and “venous thromboembolism”. A random-effects meta-analysis was conducted to obtain a pooled estimate of VTE prevalence in cancer patients undergoing chemotherapy. Results: A total of 102 eligible studies involving 30,671 patients (1773 with VTE, 28,898 without) were included in the meta-analysis. The pooled estimate of VTE prevalence was found to be 6%, ranging from 6% to 7% (ES 6%; 95% CI 6−7%; z = 18.53; p < 0.001). Conclusions: The estimated pooled prevalence rate of VTEs was 6% in cancer patients undergoing CRT, which was higher than the overall crude prevalence rate (5.78%). Comprehensive cancer care should consider stratified VTE risk assessment based on cancer phenotype, given that certain phenotypes of cancer such as bladder, gastric and ovarian posing particularly high risks of VTE.

Bevacizumab beyond Progression for Newly Diagnosed Glioblastoma (BIOMARK): Phase II Safety, Efficacy and Biomarker Study

We evaluated the efficacy and safety of bevacizumab beyond progression (BBP) in Japanese patients with newly diagnosed glioblastoma and explored predictors of response to bevacizumab. This phase II study evaluated a protocol-defined primary therapy by radiotherapy with concurrent and adjuvant temozolomide plus bevacizumab, followed by bevacizumab monotherapy, and secondary therapy (BBP: bevacizumab upon progression). Ninety patients received the protocol-defined primary therapy (BBP group, n = 25). Median overall survival (mOS) and median progression-free survival (mPFS) were 25.0 and 14.9 months, respectively. In the BBP group, in which O⁶-methylguanine-DNA methyltransferase (MGMT)-unmethylated tumors predominated, mOS and mPFS were 5.8 and 1.9 months from BBP initiation and 16.8 and 11.4 months from the initial diagnosis, respectively. The primary endpoint, the 2-year survival rate of the BBP group, was 27.0% and was unmet. No unexpected adverse events occurred. Expression profiling using RNA sequencing identified that Cluster 2, which was enriched with the genes involved in macrophage or microglia activation, was associated with longer OS and PFS independent of the MGMT methylation status. Cluster 2 was identified as a significantly favorable independent predictor for PFS, along with younger age and methylated MGMT. The novel expression classifier may predict the prognosis of glioblastoma patients treated with bevacizumab.

Congress of Neurological Surgeons systematic review and evidence-based guidelines update on the role of targeted therapies and immunotherapies in the management of progressive glioblastoma

The following questions and recommendations are pertinent to the following: TARGET POPULATION: These recommendations apply to adults with progressive GBM who have undergone standard primary treatment with surgery and/or chemoradiation. QUESTION 1: In adults with progressive glioblastoma is the use of bevacizumab as monotherapy superior to standard salvage cytotoxic chemotherapy as measured by progression free survival and overall survival?

RECOMMENDATION

Level III: Treatment with bevacizumab is suggested in the treatment of progressive GBM, as it provides improved disease control compared to historical controls as measured by best imaging response and progression free survival at 6 months, while not providing evidence for improvement in overall survival. QUESTION 2: In adults with progressive glioblastoma is the use of bevacizumab as combination therapy with cytotoxic agents superior to standard salvage cytotoxic chemotherapy as measured by progression free survival and overall survival?

RECOMMENDATION

Level III: There is insufficient evidence to show benefit or harm of bevacizumab in combination with cytotoxic therapies in progressive glioblastoma due to a lack of evidence supporting a clearly defined benefit without significant toxicity. QUESTION 3: In adults with progressive glioblastoma is the use of bevacizumab as a combination therapy with targeted agents superior to standard salvage cytotoxic chemotherapy as measured by progression free survival and overall survival?

RECOMMENDATION

There is insufficient evidence to support a recommendation regarding this question. QUESTION 4: In adults with progressive glioblastoma is the use of targeted agents as monotherapy superior to standard salvage cytotoxic chemotherapy as measured by progression free survival and overall survival?

RECOMMENDATION

There is insufficient evidence to support a recommendation regarding this question. QUESTION 5: In adults with progressive glioblastoma is the use of targeted agents in combination with cytotoxic therapies superior to standard salvage cytotoxic chemotherapy as measured by progression free survival and overall survival?

RECOMMENDATION

There is insufficient evidence to support a recommendation regarding this question. QUESTION 6: In adults with progressive glioblastoma is the use of immunotherapy monotherapy superior to standard salvage cytotoxic chemotherapy as measured by progression free survival and overall survival?

RECOMMENDATION

There is insufficient evidence to support a recommendation regarding this question. QUESTION 7: In adults with progressive glioblastoma is the use of immunotherapy in combination with targeted agents superior to standard salvage cytotoxic chemotherapy as measured by progression free survival and overall survival?

RECOMMENDATION

There is insufficient evidence to support a recommendation regarding this question. QUESTION 8: In adults with progressive glioblastoma is the use of immunotherapy in combination with bevacizumab superior to standard salvage cytotoxic chemotherapy as measured by progression free survival and overall survival?

RECOMMENDATION

There is insufficient evidence to support a recommendation regarding this question.

Therapeutic Options in Neuro-Oncology

One of the biggest challenges in neuro-oncology is understanding the complexity of central nervous system tumors, such as gliomas, in order to develop suitable therapeutics. Conventional therapies in malignant gliomas reconcile surgery and radiotherapy with the use of chemotherapeutic options such as temozolomide, chloroethyl nitrosoureas and the combination therapy of procarbazine, lomustine and vincristine. With the unraveling of deregulated cancer cell signaling pathways, targeted therapies have been developed. The most affected signaling pathways in glioma cells involve tyrosine kinase receptors and their downstream pathways, such as the phosphatidylinositol 3-kinases (PI3K/AKT/mTOR) and mitogen-activated protein kinase pathways (MAPK). MAPK pathway inhibitors include farnesyl transferase inhibitors, Ras kinase inhibitors and mitogen-activated protein extracellular regulated kinase (MEK) inhibitors, while PI3K/AKT/mTOR pathway inhibitors are divided into pan-inhibitors, PI3K/mTOR dual inhibitors and AKT inhibitors. The relevance of the immune system in carcinogenesis has led to the development of immunotherapy, through vaccination, blocking of immune checkpoints, oncolytic viruses, and adoptive immunotherapy using chimeric antigen receptor T cells. In this article we provide a comprehensive review of the signaling pathways underlying malignant transformation, the therapies currently used in the treatment of malignant gliomas and further explore therapies under development, including several ongoing clinical trials.

Congress of Neurological Surgeons Systematic Review and Evidence-Based Guidelines on the Management of Progressive Glioblastoma in Adults: Update of the 2014 Guidelines

BACKGROUND

The Institute of Medicine best practice recommendation to review guidelines every 5 years is followed by the Congress of Neurological Surgeons Guidelines Committee. The aim of this work was to provide an updated literature review and evidence-based recommendations on the topic of diagnosis and treatment of patients with progressive glioblastoma (pGBM).

OBJECTIVE

To review the literature published since the last guidelines on pGBM dated 2014, with literature search ending in June 2012.

METHODS

PubMed, Embase, and Cochrane were searched for the period July 1, 2012, to March 31, 2019, using search terms and search strategies to identify pertinent abstracts. These were then screened using published exclusion/inclusion criteria to identify full-text review articles. Evidence tables were constructed using data derived from full-text reviews and recommendations made from the evidence derived.

RESULTS

From the total 8786 abstracts identified by the search, 237 full-text articles met inclusion/exclusion criteria and were included in this update. Two new level II recommendations derived from this work. For the diagnosis of patients with GBM, the use of diffusion-weighted images is recommended to be included in the magnetic resonance images with and without contrast used for surveillance to detect pGBM. For the treatment of patients with pGBM, repeat cytoreductive surgery is recommended to improve overall survival. An additional 21 level III recommendations were provided.

CONCLUSION

Recent published literature provides new recommendations for the diagnosis and treatment of pGBM. The Central Nervous System Guidelines Committee will continue to pursue timely updates to further improve the care of patients with diagnosis.https://www.cns.org/guidelines/browse-guidelines-detail/guidelines-management-of-progressive-glioblastoma.

Efficacy and safety of bevacizumab combined with temozolomide in the treatment of recurrent malignant gliomas and its influence on serum tumor markers

OBJECTIVE

To determine the efficacy and safety of bevacizumab (Bz) combined with temozolomide (TMZ) in the treatment of recurrent malignant gliomas and its influence on serum tumor markers (STMs).

METHODS

The clinical data of 73 patients with recurrent malignant gliomas admitted to the First People's Hospital of Shuangliu District from April 2016 to June 2018 were analyzed retrospectively. Patients were divided into two groups according to different therapies: the control group (n=33) treated with TMZ, and the research group (n=40) treated with Bz combined with TMZ (Bz+TMZ). The overall response rate (ORR), disease control rate (DCR) and incidence of adverse reactions (ARs) were observed after 4 courses of treatment. The levels of STMs were detected. Additionally, the Karnofsky Performance Scale (KPS) score and quality of life (QoL) before and after treatment were compared between the two groups. The 1-year and 2-year survival rates as well as median survival time (MST) were also compared after 2-year follow-up. Treatment satisfaction was recorded and compared.

RESULTS

After treatment, the research group exhibited better ORR and DCR than the control group; The incidence of ARs differed insignificantly between the two arms; The serum levels of Vascular endothelial growth factor (VEGF), epidermal growth factor (EGF) and transforming growth factor β (TGF-β) in the research group were statistically lower than those in the control group; The KPS score and QoL score increased significantly in both arms, and were higher in the research group compared with the control group; the research group was also superior to the control group in treatment satisfaction. The research group showed higher 1-year and 2-year survival rates than the control group.

CONCLUSIONS

BZ+TMZ is effective in treating recurrent malignant gliomas, which can improve the QoL and survival of patients.

Efficacy and safety of bevacizumab in the treatment of adult gliomas: a systematic review and meta-analysis

OBJECTIVE

To assess the efficacy and safety of bevacizumab (BEV) in patients with glioma.

DESIGN

Systematic review and meta-analysis.

PARTICIPANTS

Adults aged 18 years and above, whose histology was confirmed to be malignant glioma.

PRIMARY AND SECONDARY OUTCOME MEASURES

The main indicators included progression-free survival (PFS) rate and overall survival (OS) rate, and the secondary indicators were adverse reactions.

RESULTS

A total of 11 clinical centre trials were included in this study for meta-analysis, including 2392 patients. The results of the meta-analysis showed that the median PFS rate of the BEV group was significantly higher than that of the non-BEV group (p<0.00001). When comparing PFS between two groups, we found that the PFS in the BEV group was higher than that in the non-BEV group at 6 months (OR 3.31, 95% CI 2.74 to 4.00, p<0.00001), 12 months (OR 2.05, 95% CI 1.70 to 2.49, p<0.00001) and 18 months (OR 1.31, 95% CI 1.02 to 1.69, p=0.03). But at 24 months (OR 0.83, 95% CI 0.50 to 1.37, p=0.47), there was no significant difference between the two groups. At 30 months (OR 0.62, 95% CI 0.39 to 0.97, p=0.04), the PFS of the BEV group was lower than that of the non-BEV group. Moreover, The results showed that BEV had no significant effect on improving OS, but the adverse reaction in BEV group was significantly higher than that in non-BEV group.

CONCLUSION

The evidence suggests that BEV can significantly prolong the PFS of patients with glioma within 18 months and shorten the PFS of patients after 30 months. This limitation may be related to the subgroup of patients, the change of recurrence mode, the optimal dose of drug, the increase of hypoxia, the enhancement of invasiveness and so on. Therefore, it is necessary to carry out more samples and higher quality large-scale research in the future.

Novel Ion Channel Targets and Drug Delivery Tools for Controlling Glioblastoma Cell Invasiveness

Comprising more than half of all brain tumors, glioblastoma multiforme (GBM) is a leading cause of brain cancer-related deaths worldwide. A major clinical challenge is presented by the capacity of glioma cells to rapidly infiltrate healthy brain parenchyma, allowing the cancer to escape control by localized surgical resections and radiotherapies, and promoting recurrence in other brain regions. We propose that therapies which target cellular motility pathways could be used to slow tumor dispersal, providing a longer time window for administration of frontline treatments needed to directly eradicate the primary tumors. An array of signal transduction pathways are known to be involved in controlling cellular motility. Aquaporins (AQPs) and voltage-gated ion channels are prime candidates as pharmacological targets to restrain cell migration in glioblastoma. Published work has demonstrated AQPs 1, 4 and 9, as well as voltage-gated potassium, sodium and calcium channels, chloride channels, and acid-sensing ion channels are expressed in GBM and can influence processes of cell volume change, extracellular matrix degradation, cytoskeletal reorganization, lamellipodial and filopodial extension, and turnover of cell-cell adhesions and focal assembly sites. The current gap in knowledge is the identification of optimal combinations of targets, inhibitory agents, and drug delivery systems that will allow effective intervention with minimal side effects in the complex environment of the brain, without disrupting finely tuned activities of neuro-glial networks. Based on published literature, we propose that co-treatments using AQP inhibitors in addition to other therapies could increase effectiveness, overcoming some limitations inherent in current strategies that are focused on single mechanisms. An emerging interest in nanobodies as drug delivery systems could be instrumental for achieving the selective delivery of combinations of agents aimed at multiple key targets, which could enhance success in vivo.

Regulation of autophagy as a therapeutic option in glioblastoma

Around three out of one hundred thousand people are diagnosed with glioblastoma multiforme, simply called glioblastoma, which is the most common primary brain tumor in adults. With a dismal prognosis of a little over a year, receiving a glioblastoma diagnosis is oftentimes fatal. A major advancement in its treatment was made almost two decades ago when the alkylating chemotherapeutic agent temozolomide (TMZ) was combined with radiotherapy (RT). Little progress has been made since then. Therapies that focus on the modulation of autophagy, a key process that regulates cellular homeostasis, have been developed to curb the progression of glioblastoma. The dual role of autophagy (cell survival or cell death) in glioblastoma has led to the development of autophagy inhibitors and promoters that either work as monotherapies or as part of a combination therapy to induce cell death, cellular senescence, and counteract the ability of glioblastoma stem cells (GSCs) for initiating tumor recurrence. The myriad of cellular pathways that act upon the modulation of autophagy have created contention between two groups: those who use autophagy inhibition versus those who use promotion of autophagy to control glioblastoma growth. We discuss rationale for using current major therapeutics, their molecular mechanisms for modulation of autophagy in glioblastoma and GSCs, their potentials for making strides in combating glioblastoma progression, and their possible shortcomings. These shortcomings may fuel the innovation of novel delivery systems and therapies involving TMZ in conjunction with another agent to pave the way towards a new gold standard of glioblastoma treatment.

Efficacy and safety of nivolumab in Japanese patients with first recurrence of glioblastoma: an open-label, non-comparative study

BACKGROUND

An open-label, non-comparative study assessed the efficacy and safety of nivolumab in Japanese patients with first recurrence glioblastoma.

METHODS

Patients with first recurrence of histologically confirmed World Health Organization Grade IV glioma, after treatment with temozolomide and radiotherapy, received nivolumab 3 mg/kg every 2 weeks until confirmed disease progression (Response Assessment in Neuro-Oncology criteria) or toxicity. Primary endpoint was 1-year overall survival rate assessed by Bayesian approach. The prespecified efficacy criterion was that the Bayesian posterior probability threshold for exceeding the 1-year overall survival of bevacizumab (34.5%) from the Japanese phase 2 study (JO22506) would be 93%.

RESULTS

Of the 50 enrolled patients, 44 (88.0%) had recurrent malignant glioma (glioblastoma, gliosarcoma), and of these, 26 (59.1%) had at least one measurable lesion at baseline. The Bayesian posterior mean 1-year overall survival (90% Bayesian credible intervals) with nivolumab was 54.4% (42.27-66.21), and the Bayesian posterior probability of exceeding the threshold of the 1-year overall survival rate of bevacizumab (34.5%) was 99.7%. Median (90% confidence interval) overall and progression-free survival was 13.1 (10.4-17.7) and 1.5 (1.4-1.5) months, respectively. One partial response was observed (objective response rate 1/26 evaluable patients [3.8%]). Treatment-related adverse event rates were 14.0% for Grade 3-4 and 2.0% for Grade 5; most adverse events resolved and were manageable.

CONCLUSIONS

The 1-year overall survival with nivolumab monotherapy in Japanese patients with glioblastoma met the prespecified efficacy criterion. The safety profile of nivolumab was consistent with that observed in other tumor types.

CLINICAL TRIAL REGISTRATION

JapicCTI-152967.

Outcomes of salvage fractionated re-irradiation combined with bevacizumab for recurrent high-grade gliomas that progressed after bevacizumab treatment*

BACKGROUND

There is no standard treatment for patients with recurrent high-grade gliomas who progress after bevacizumab treatment. We evaluated the outcomes of re-irradiation combined with bevacizumab for patients refractory to bevacizumab.

METHODS

Between January 2015 and September 2019, patients with progression after bevacizumab treatment were treated with re-irradiation combined with bevacizumab (25 Gy in five fractions).

RESULTS

Fourteen patients [glioblastoma, isocitrate dehydrogenase (IDH) wild type (N = 6), glioblastoma, IDH mutant (N = 4), anaplastic astrocytoma, IDH wild type (N = 1), anaplastic astrocytoma, IDH mutant (N = 1), glioblastoma, not otherwise specified (N = 1) and radiologically diagnosed brainstem glioma (N = 1)] were included in this study. The median survival and progression-free survival times after re-irradiation combined with bevacizumab were 6.1 and 3.8 months, respectively. The 6-month survival and progression-free survival rates were 54.5 and 15.7%, respectively. Patients with a Karnofsky performance status of ≥70 tended to have longer median survival time (9.3 vs. 5.4 months, respectively; P = 0.058) and had a significantly longer median progression-free survival time (4.2 vs. 3.7 months, respectively; P = 0.046) than those with a Karnofsky performance status of <70. Four patients (28.6%) achieved a complete or partial radiological response, and three patients (21.4%) had an improved Karnofsky performance status after re-irradiation combined with bevacizumab. Grade 3/4 toxicities included leukopenia in four patients (28.6%), hypertension in three (21.4%), proteinuria in one (7.1%) and gastrointestinal hemorrhage in one (7.1%).

CONCLUSIONS

Re-irradiation combined with bevacizumab for patients with recurrent high-grade gliomas who progress after bevacizumab treatment was feasible. Re-irradiation combined with bevacizumab is a potential treatment option, especially for patients with a Karnofsky performance status of ≥70.

Novel Receptor Tyrosine Kinase Pathway Inhibitors for Targeted Radionuclide Therapy of Glioblastoma

Glioblastoma (GB) remains the most fatal brain tumor characterized by a high infiltration rate and treatment resistance. Overexpression and/or mutation of receptor tyrosine kinases is common in GB, which subsequently leads to the activation of many downstream pathways that have a critical impact on tumor progression and therapy resistance. Therefore, receptor tyrosine kinase inhibitors (RTKIs) have been investigated to improve the dismal prognosis of GB in an effort to evolve into a personalized targeted therapy strategy with a better treatment outcome. Numerous RTKIs have been approved in the clinic and several radiopharmaceuticals are part of (pre)clinical trials as a non-invasive method to identify patients who could benefit from RTKI. The latter opens up the scope for theranostic applications. In this review, the present status of RTKIs for the treatment, nuclear imaging and targeted radionuclide therapy of GB is presented. The focus will be on seven tyrosine kinase receptors, based on their central role in GB: EGFR, VEGFR, MET, PDGFR, FGFR, Eph receptor and IGF1R. Finally, by way of analyzing structural and physiological characteristics of the TKIs with promising clinical trial results, four small molecule RTKIs were selected based on their potential to become new therapeutic GB radiopharmaceuticals.

Accelerator-based BNCT for patients with recurrent glioblastoma: a multicenter phase II study

Background

Boron neutron capture therapy (BNCT) utilizes tumor-selective particle radiation. This study aimed to assess the safety and efficacy of accelerator-based BNCT (AB-BNCT) using a cyclotron-based neutron generator (BNCT 30) and ¹⁰B-boronophenylalanine (SPM-011) in patients with recurrent malignant glioma (MG) (primarily glioblastoma [GB]).

Methods

This multi-institutional, open-label, phase II clinical trial involved 27 recurrent MG cases, including 24 GB cases, who were enrolled from February 2016 to June 2018. The study was conducted using the abovementioned AB-BNCT system, with 500 mg/kg SPM-011 (study code: JG002). The patients were bevacizumab-naïve and had recurrent MG after standard treatment. The primary endpoint was the 1-year survival rate, and the secondary endpoints were overall survival (OS) and progression-free survival (PFS). Results were compared to those of a previous Japanese domestic bevacizumab trial for recurrent GB (JO22506).

Results

The 1-year survival rate and median OS of the recurrent GB cases in this trial were 79.2% (95% CI: 57.0–90.8) and 18.9 months (95% CI: 12.9–not estimable), respectively, whereas those of JO22506 were 34.5% (90% CI: 20.0–49.0) and 10.5 months (95% CI: 8.2–12.4), respectively. The median PFS was 0.9 months (95% CI: 0.8–1.0) by the RANO criteria. The most prominent adverse event was brain edema. Twenty-one of 27 cases were treated with bevacizumab following progressive disease.

Conclusions

AB-BNCT demonstrated acceptable safety and prolonged survival for recurrent MG. AB-BNCT may increase the risk of brain edema due to re-irradiation for recurrent MG; however, this appears to be controlled well with bevacizumab.

Transcriptome analysis revealed CENPF associated with glioma prognosis

Gliomas are common malignant tumors of the central nervous system. Despite the surgical resection and postoperative radiotherapy and chemotherapy, the prognosis of glioma remains poor. Therefore, it is important to reveal the molecular mechanisms that promotes glioma progression. Microarray datasets were obtained from the Gene Expression Omnibus (GEO) database. The GEO2R tool was used to identify 428 differentially expressed genes (DEGs) and a core module from three microarray datasets. Heat maps were drawn based on DEGs. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were performed using the DAVID database. The core module was significantly involved in several KEGG pathways, such as "cell cycle", "viral carcinogenesis", "progesterone-mediated oocyte maturation", "p53 signaling pathway". The protein-protein interaction (PPI) networks and modules were built using the STRING database and the MCODE plugin, respectively, which were visualized using Cytoscape software. Identification of hub genes in the core module using the CytoHubba plugin. The top modular genes AURKA, CDC20, CDK1, CENPF, and TOP2A were associated with glioma development and prognosis. In the Human Protein Atlas (HPA) database, CDC20, CENPF and TOP2A have significant protein expression. Univariate and multivariate cox regression analysis showed that only CENPF had independent influencing factors in the CGGA database. GSEA analysis found that CENPF was significantly enriched in the cell cycle, P53 signaling pathway, MAPK signaling pathway, DNA replication, spliceosome, ubiquitin-mediated proteolysis, focal adhesion, pathway in cancer, glioma, which was highly consistent with previous studies. Our study revealed a core module that was highly correlated with glioma development. The key gene CENPF and signaling pathways were identified through a series of bioinformatics analysis. CENPF was identified as a candidate biomarker molecule.

A Single Arm Prospective Pilot Study Examining the Efficacy and Safety of Bevacizumab Single Maintenance Therapy Following Platinum-Based Chemotherapy in Patients with Advanced or Recurrent Cervical Cancer

Although the addition of bevacizumab to platinum-based combination chemotherapy has been recommended as a standard regimen for patients with advanced or recurrent cervical cancer, there is no clear evidence regarding the effectiveness of bevacizumab monotherapy as salvage chemotherapy. This study prospectively examined the efficacy and safety of switching from platinum-based chemotherapy combined with bevacizumab to single maintenance therapy in patients with advanced or recurrent cervical cancer. Patients were first treated with standard combination chemotherapy. However, if chemotherapy was discontinued because of an adverse event, bevacizumab monotherapy was continued for patients who agreed to participate in this study and provided written informed consent. The study protocol was approved by the Independent Review Board of Tohoku University School of Medicine (reception number 2017-1-540). A total of 15 patients (median age of 55 years, range 33-69 years) participated in this study. The median number of cycles of bevacizumab single maintenance administration was 8, and the main reasons for discontinuation were disease progression and adverse events. Bevacizumab single maintenance therapy had a disease control rate of 53.3% (CR 40%, PR 6.7%, SD 6.7%). The most frequent grade 3/4 clinical adverse events were proteinuria (5/15) and hypertension (4/15). No treatment-related deaths occurred. Bevacizumab single maintenance therapy was effective as salvage chemotherapy in patients with advanced or recurrent cervical cancer, and the safety profile was generally consistent with those reported in previous studies of bevacizumab monotherapy.

Safety and efficacy of VB-111, an anticancer gene therapy, in patients with recurrent glioblastoma: results of a phase I/II study

BACKGROUND

VB-111 is a non-replicating adenovirus carrying a Fas-chimera transgene, leading to targeted apoptosis of tumor vascular endothelium and induction of a tumor-specific immune response. This phase I/II study evaluated the safety, tolerability, and efficacy of VB-111 with and without bevacizumab in recurrent glioblastoma (rGBM).

METHODS

Patients with rGBM (n = 72) received VB-111 in 4 treatment groups: subtherapeutic (VB-111 dose escalation), limited exposure (LE; VB-111 monotherapy until progression), primed combination (VB-111 monotherapy continued upon progression with combination of bevacizumab), and unprimed combination (upfront combination of VB-111 and bevacizumab). The primary endpoint was median overall survival (OS). Secondary endpoints were safety, overall response rate, and progression-free survival (PFS).

RESULTS

VB-111 was well tolerated. The most common adverse event was transient mild-moderate fever. Median OS time was significantly longer in the primed combination group compared with both LE (414 vs 223 days; hazard ratio [HR], 0.48; P = 0.043) and unprimed combination (414 vs 141.5 days; HR, 0.24; P = 0.0056). Patients in the combination phase of the primed combination group had a median PFS time of 90 days compared with 60 in the LE group (HR, 0.36; P = 0.032), and 63 in the unprimed combination group (P = 0.72). Radiographic responders to VB-111 exhibited characteristic, expansive areas of necrosis in the areas of initial enhancing disease.

CONCLUSIONS

Patients with rGBM who were primed with VB-111 monotherapy that continued after progression with the addition of bevacizumab showed significant survival and PFS advantage, as well as specific imaging characteristics related to VB-111 mechanism of action. These results warrant further assessment in a randomized controlled study.

The Safety and Efficacy of Bevacizumab for Radiosurgery - Induced Steroid - Resistant Brain Edema; Not the Last Part in the Ship of Theseus

Background

Radiation-induced brain edema (RIBE) is a serious complication of radiation therapy. It may result in dramatic clinico-radiological deterioration. At present, there are no definite guidelines for management of the complication. Corticosteroids are the usual first line of treatment, which frequently fails to provide long-term efficacy in view of its adverse complication profile. Bevacizumab has been reported to show improvement in cases of steroid-resistant radiation injury. The objective of this study is to evaluate the role of Bevacizumab in post-radiosurgery RIBE.

Material and Methods

Since 2012, 189 out of 1241 patients who underwent radiosurgery at our institution developed post-radiosurgery RIBE, 17 of which did not respond to high-dose corticosteroids. We systematically reviewed these 17 patients of various intracranial pathologies with clinic-radiological evidence of RIBE following gamma knife radiosurgery (GKRS). All patients received protocol-based Bevacizumab therapy. The peer-reviewed literature was evaluated.

Results

82 percent of the patients showed improvement after starting Bevacizumab. The majority began to improve after the third cycle started improvement after the third cycle of Bevacizumab. Clinical improvement preceded radiological improvement by an average of eight weeks. The first dose was 5 mg/kg followed by 7.5-10 mg/kg at with two-week intervals. Bevacizumab needs to be administered for an average of seven cycles (range 5-27, median 7) for best response. Steroid therapy could be tapered in most patients by the first follow-up. One patient did not respond to Bevacizumab and needed surgical decompression for palliative care. One noncompliant patient died due to radiation injury.

Conclusion

Bevacizumab is a effective and safe for treatment of RIBE after GKRS. A protocol-based dose schedule in addition to frequent clinical and radiological evaluations are required. Bevacizumab should be considered as an early treatment option for RIBE.

Safety and effectiveness of bevacizumab in Japanese patients with malignant glioma: a post-marketing surveillance study

Objective

This surveillance study was conducted to verify the post-market safety and effectiveness of bevacizumab, which was approved in Japan in 2013 for the treatment of patients with newly diagnosed and or recurrent malignant glioma.

Methods

This was a prospective, observational, multicenter post-marketing surveillance study. Patients with newly diagnosed or recurrent malignant glioma scheduled for bevacizumab treatment were enrolled. The incidence and severity of adverse drug reactions were calculated. The effectiveness of bevacizumab was assessed by the 1-year survival rate and the overall survival rate.

Results

The safety analysis set and the effectiveness analysis set each comprised 258 of the 268 enrolled patients: tumours were newly diagnosed in 80 patients (31%) and recurrent in 178 patients (68.9%). The incidence of grade ≥ 3 adverse drug reactions was 15.1%. Adverse drug reactions of special interest included 14 cerebral bleeding events and 11 infections. Of the 80 patients with newly diagnosed malignant glioma, 44 (55%) were alive throughout the 18-month observation period. The 1-year survival rate for patients with newly diagnosed glioblastoma was 78%. Median overall survival was not calculated, but 51.2% of patients were alive at the last date of observation of the last observed patient. In patients with recurrent glioblastoma, the 1-year survival rate was 38.9%, and the median overall survival was 10.2 months.

Conclusions

The results suggest no new safety concerns, and the effectiveness might be similar to previously reported data in clinical trials. Therefore, bevacizumab is considered as one of the treatment options for patients with malignant glioma in real-world clinical practice.

The evolving role of antiangiogenic therapies in glioblastoma multiforme: current clinical significance and future potential

Introduction: Glioblastoma multiforme (GBM) is the most common primary malignant brain tumor in adults, but its prognosis remains poor despite significant advances in our understanding of its molecular biology and investigation of numerous treatment modalities. Despite conventional treatment consisting of surgical resection, radiotherapy, and temozolomide marginally prolonging survival, most GBM patients die within 2 years of initial diagnosis. Bevacizumab (Bev) is the best-studied antiangiogenic agent for GBM and currently the only FDA-approved second-line treatment. Areas covered: Areas covered in this review include the molecular pathways of angiogenesis in glioblastoma, specifically the overexpression of vascular endothelial growth factor (VEGF) and robust formation of tumor neovasculature. In addition, this review covers pharmacological targeting of this process as a longstanding attractive clinical strategy, specifically by Bev. Expert opinion: This review attempts to discuss the history of early studies of antiangiogenic treatment for GBM that eventually failed in subsequent studies and the evolving modern role of Bev in the course of treatment for a variety of indications, including symptom control, reduced glucocorticoid use, and improved quality of life.

A Pilot Study of Vaccine Therapy with Multiple Glioma Oncoantigen/Glioma Angiogenesis-Associated Antigen Peptides for Patients with Recurrent/Progressive High-Grade Glioma

High-grade gliomas (HGGs) carry a dismal prognosis despite current treatments. We previously confirmed the safety and immunogenicity of a vaccine treatment targeting tumor angiogenesis with synthetic peptides, for vascular endothelial growth factor receptor (VEGFR) epitopes in recurrent HGG patients. In this study, we evaluated a novel vaccine therapy targeting not only tumor vasculature but also tumor cells, using multiple glioma oncoantigen (GOA)/glioma angiogenesis-associated antigen (GAAA) peptides in HLA-A2402+ recurrent/progressive HGG patients. The vaccine included peptide epitopes from four GOAs (LY6K, DEPDC1, KIF20A, and FOXM1) and two GAAAs (VEGFR1 and VEGFR2). Ten patients received subcutaneous vaccinations. The primary endpoint was the safety of the treatment. T-lymphocyte responses against GOA/GAAA epitopes and treatment response were evaluated secondarily. The treatment was well tolerated without any severe systemic adverse events. The vaccinations induced immunoreactivity to at least three vaccine-targeted GOA/GAAA in all six evaluable patients. The median overall survival time in all patients was 9.2 months. Five achieved progression-free status lasting at least six months. Two recurrent glioblastoma patients demonstrated stable disease. One patient with anaplastic oligoastrocytoma achieved complete response nine months after the vaccination. Taken together, this regimen was well tolerated and induced robust GOA/GAAA-specific T-lymphocyte responses in recurrent/progressive HGG patients.

A pilot study of peptide vaccines for VEGF receptor 1 and 2 in patients with recurrent/progressive high grade glioma

Object

Early-phase clinical studies of glioma vaccines have shown feasibility and encouraging preliminary clinical activity. A vaccine that targets tumor angiogenesis factors in glioma microenvironment has not been reported. Therefore, we performed a pilot study to evaluate the safety and immunogenicity of a novel vaccination targeting tumor angiogenesis with synthetic peptides for vascular endothelial growth factor (VEGF) receptor epitopes in patients with recurrent/progressive high grade gliomas.

Methods

Eight patients received intranodal vaccinations weekly at a dose of 2mg/kg bodyweight 8 times. T-lymphocyte responses against VEGF receptor (VEGFR) epitopes were assessed by enzyme linked immunosorbent spot assays.

Results

This treatment was well-tolerated in patients. The first four vaccines induced positive immune responses against at least one of the targeted VEGFR epitopes in the peripheral blood mononuclear cells in 87.5% of patients. The median overall survival time in all patients was 15.9 months. Two achieved progression-free status lasting at least 6 months. Two patients with recurrent GBM demonstrated stable disease. Plasma IL-8 level was negatively correlated with overall survival.

Conclusion

These data demonstrate the safety and immunogenicity of VEGFR peptide vaccines targeting tumor vasculatures in high grade gliomas.

Nivolumab with or without ipilimumab in patients with recurrent glioblastoma: results from exploratory phase I cohorts of CheckMate 143

Background

Immunotherapies have demonstrated efficacy across a diverse set of tumors supporting further evaluation in glioblastoma. The objective of this study was to evaluate the safety/tolerability and describe immune-mediated effects of nivolumab ± ipilimumab in patients with recurrent glioblastoma. Exploratory efficacy outcomes are also reported.

Methods

Patients were randomized to receive nivolumab 3 mg/kg every 2 weeks (Q2W; NIVO3) or nivolumab 1 mg/kg + ipilimumab 3 mg/kg every 3 weeks (Q3W) for 4 doses, then nivolumab 3 mg/kg Q2W (NIVO1+IPI3). An alternative regimen of nivolumab 3 mg/kg + ipilimumab 1 mg/kg Q3W for 4 doses, then nivolumab 3 mg/kg Q2W (NIVO3+IPI1) was investigated in a nonrandomized arm.

Results

Forty patients were enrolled (NIVO3, n = 10; NIVO1+IPI3, n = 10; NIVO3+IPI1, n = 20). The most common treatment-related adverse events (AEs) were fatigue (NIVO3, 30%; NIVO1+IPI3, 80%; NIVO3+IPI1, 55%) and diarrhea (10%, 70%, 30%, respectively). AEs leading to discontinuation occurred in 10% (NIVO3), 30% (NIVO1+IPI3), and 20% (NIVO3+IPI1) of patients. Three patients achieved a partial response (NIVO3, n = 1; NIVO3+IPI1, n = 2) and 8 had stable disease for ≥12 weeks (NIVO3, n = 2; NIVO1+IPI3, n = 2; NIVO3+IPI1, n = 4 [Response Assessment in Neuro-Oncology criteria]). Most patients (68%) had tumor-cell programmed death ligand-1 expression ≥1%. Immune-mediated effects mimicking radiographic progression occurred in 2 patients.

Conclusions

Nivolumab monotherapy was better tolerated than nivolumab + ipilimumab; the tolerability of the combination was influenced by ipilimumab dose. These safety and exploratory findings merit further investigation of immunotherapies in glioblastoma.

Effectiveness of Stereotactic Radiotherapy and Bevacizumab for Recurrent High-Grade Gliomas: A Potential Therapy for Isocitrate Dehydrogenase Wild-Type Recurrent High-Grade Gliomas

OBJECTIVE

This study aimed to evaluate the efficacy of stereotactic radiotherapy combined with bevacizumab (SRT-Bv) compared with Bv treatment for recurrent high-grade gliomas (HGGs).

METHODS

Data for patients with recurrent HGGs who received SRT and Bv (n = 29) or Bv (n = 29) between June 2014 and September 2016 were retrospectively analyzed. All patients received conventional radiotherapy (total, 60 Gy) before this study. SRT was administered at a median dose of 42 Gy in 3-7 fractions. The recurrence pattern was classified into 3 groups: in-field, marginal, and out-field.

RESULTS

The median overall survival in the SRT-Bv group was significantly longer than that in the Bv group (10.4 vs. 5.6 months; P = 0.02). In patients with isocitrate dehydrogenase wild-type tumors, the SRT-Bv treatment significantly prolonged survival more than the Bv treatment (10.9 vs. 8.2 months; P = 0.01). The World Health Organization grade and presence or absence of SRT were significant prognostic factors in the univariate analysis. Besides brain edema in 2 cases and asymptomatic subdural hematoma in 1 case, no other severe adverse effect due to SRT-Bv treatment was recorded. The pattern of recurrence was as follows: in-field, 2 cases (7%); marginal, 8 cases (28%); out-field, 11 cases (38%); no recurrence on radiologic findings, 6 cases (21%); and uncertain, 2 cases (7%).

CONCLUSIONS

SRT-Bv treatment significantly prolonged survival duration more than Bv treatment and provides good local control in patients with recurrent HGGs, especially those with isocitrate dehydrogenase wild-type tumors.

Bevacizumab in temozolomide refractory high-grade gliomas: single-centre experience and review of the literature

Background

Despite multidisciplinary treatment approaches, the prognosis for patients with high-grade glioma (HGG) is poor, with a median overall survival (OS) of 14.6 months for glioblastoma multiforme (GB). As high levels of vascular endothelial growth factor A (VEGF) are found in HGG, targeted anti-antiangiogenic therapy using the humanized monoclonal antibody bevacizumab (BEV) was studied in a series of clinical trials. Still, the discrepancy of BEV's efficacy with regard to initial clinical and radiological response and its reported failure to prolong survival remains to be explained. Here, we illustrate the effectiveness of BEV in recurrent HGG by summarizing our single-centre experience.

Methods

We have retrospectively investigated the effect of BEV in temozolomide refractory HGG in 39 patients treated at the University Hospital of Ulm, Germany.

Results

Median duration of BEV treatment was 12.5 weeks; 23% of patients received BEV for more than 6 months and 15% for more than 1 year, until clinical or radiological tumour progression led to discontinuation. Furthermore, Karnofsky performance status increased in 30.6% and steroid dose decreased in 39% of all patients.

Conclusions

The review of literature reveals that phase II and III studies support BEV as an effective therapy in recurrent HGG, at least with regard to progression-free survival (PFS), but landmark phase III trials failed to prove benefit concerning OS. Here, we discuss reasons that may account for this observation. We conclude that prolonging PFS with maintenance of neurological function and personal and economic independency justifies the off-label use of BEV.

A retrospective study of bevacizumab for treatment of brainstem glioma with malignant features

Brainstem glioma is impossible to resect completely, and patients with this type of glioma show a poor prognosis. Therefore, a more effective adjuvant therapy is required to prolong survival. Bevacizumab is an endothelial growth factor monoclonal antibody with strong anti-vascular effects, which may suppress tumor progression. We performed a retrospective study of data from 6 patients with brainstem glioma showing malignant features who were treated with bevacizumab. Tumor-associated lesions, as evaluated by T2 weighted or fluid-attenuated inversion-recovery magnetic resonance imaging, were reduced in all patients, although the timing of the start of bevacizumab administration and pretreatment were not uniform. Clinical symptoms improved in 4 patients and progression was inhibited in 2 patients. The Karnofsky performance status improved from 56.7 to 71.7 on average. The median reduction ratio of tumor-associated lesions was 76.3%, but tumor suppression did not last in any of the cases. Furthermore, 5 patients died of tumor progression, and 1 patient died of a complication of necrotizing colitis. The median progression-free survival after bevacizumab administration was 7 months. The median overall survival after diagnosis was 16.5 months. Bevacizumab might be a potential therapeutic option for progressive brainstem gliomas with malignant features.

Bevacizumab as a last-line treatment for glioblastoma following failure of radiotherapy, temozolomide and lomustine

In previous trials, bevacizumab failed to prolong the overall survival time in newly diagnosed glioblastoma and at the first recurrence. Randomized clinical trials at the second or further recurrence following the failure of radiotherapy, temozolomide and lomustine, and retrospective analyses focusing on this specific cohort, are not yet available. A total of 62 patients with glioblastoma who received bevacizumab after the failure of standard care, including radiotherapy, temozolomide and lomustine, were retrospectively identified. Patient characteristics, previous treatment details, concomitant therapy, response based on the Response Assessment in Neuro-Oncology criteria, and progression-free survival (PFS) and overall survival (OS) times and rates were evaluated. Furthermore, the PFS and OS times and rates were analyzed for responders and non-responders. Of the patients, 54.8% (n=34) responded to treatment [complete response (CR) 3.2%, n=2; partial response (PR) 51.6%, n=32]. The median PFS time was 3.5 months and the median OS time was 7.5 months. The PFS rate at 6 months was 21.5% and the OS rate at 12 months was 11.5%. Responders (CR or PR) experienced a superior median PFS time compared with non-responders (i.e. stable or progressive disease; 5.4 vs. 1.9 months; P<0.0001) and a superior PFS rate at 6 months (34.9 vs. 7.1%; P<0.0001). The median OS time (8.6 vs. 6.4 months; P<0.0001) and OS rate at 12 months (21.3 vs. 0%; P<0.0001) were also superior in patients who exhibited a response to bevacizumab treatment. In conclusion, the objective response rate and the PFS and OS times and rates indicate that bevacizumab has activity in patients with glioblastoma following the failure of radiotherapy, temozolomide, and lomustine. A randomized trial comparing bevacizumab with best supportive care in these patients is advised.

Bevacizumab for malignant gliomas: current indications, mechanisms of action and resistance, and markers of response

Vascular endothelial growth factor (VEGF) is an attractive target of antiangiogenic therapy in glioblastomas. Bevacizumab (Bev), a humanized anti-VEGF antibody, is associated with the improvement of progression-free survival and performance status in patients with glioblastoma. However, randomized trials uniformly suggest that these favorable clinical effects of Bev do not translate into an overall survival benefit. The mechanisms of action of Bev appear to include the inhibition of tumor angiogenesis, as well as indirect effects such as the depletion of niches for glioma stem cells and stimulation of antitumor immunity. Although several molecules/pathways have been reported to mediate adaptation and resistance to Bev, including the activation of alternative pro-angiogenic pathways, the resistance mechanisms have not been fully elucidated; for example, the mechanism that reinduces tumor hypoxia remains unclarified. The identification of imaging characteristics or biomarkers predicting the response to Bev, as well as the better understanding of the mechanisms of action and resistance, is crucial to improve the overall clinical outcome and optimize individual therapy. In this article, the authors review the results of important clinical trials/studies, the current understanding of the mechanisms of action and resistance, and the knowledge of imaging characteristics and biomarkers predicting the response to Bev.

Phase I/II Study of Temozolomide Plus Nimustine Chemotherapy for Recurrent Malignant Gliomas: Kyoto Neuro-oncology Group

The objective of this phase I/II study was to examine the efficacy and toxicity profile of temozolomide (TMZ) plus nimustine (ACNU). Patients who had received a standard radiotherapy with one or two previous chemo-regimens were enrolled. In phase I, the maximum-tolerated dose (MTD) by TMZ (150 mg/m2/day) (Day 1-5) plus various doses of ACNU (30, 35, 40, 45 mg/m2/day) (Day 15) per 4 weeks was defined on a standard 3 + 3 design. In phase II, these therapeutic activity and safety of this regimen were evaluated. Forty-nine eligible patients were enrolled. The median age was 50 years-old. Eighty percent had a KPS of 70-100. Histologies were glioblastoma (73%), anaplastic astrocytoma (22%), anaplastic oligodendroglioma (4%). In phase I, 15 patients were treated at four cohorts by TMZ plus ACNU. MTD was TMZ (150 mg/m2) plus ACNU (40 mg/m2). In phase II, 40 patients were treated at the dose of cohort 3 (MTD). Thirty-five percent of patients experienced grade 3 or 4 toxicities, mainly hematologic. The overall response rate was 11% (4/37). Sixty-eight percent (25/37) had stable disease. Twenty-two percent (8/37) showed progression. Progression-free survival (PFS) rates at 6 and 12 months were 24% (95% CI, 12-35%) and 8% (95% CI, 4-15%). Median PFS was 13 months (95% CI, 9.2-17.2 months). Overall survival (OS) at 6 and 12 were 78% (95% CI, 67-89%) and 49% (95% CI, 33-57%). Median OS was 11.8 months (95% CI, 8.2-14.5 months). This phase I/II study showed a moderate toxicity in hematology and may has a promising efficacy in OS, without inferiority in PFS.

Effect of Bevacizumab Plus Temozolomide-Radiotherapy for Newly Diagnosed Glioblastoma with Different MGMT Methylation Status: A Meta-Analysis of Clinical Trials

BACKGROUND MGMT methylation status can influence the therapeutic effect and prognosis of glioblastoma (GBM). There are conflicting results from studies evaluating the efficacy of bevacizumab (BV) when it is combined with temozolomide (TMZ) and radiotherapy (RT) in patients diagnosed with GBM with different MGMT methylation status. MATERIAL AND METHODS Data were extracted from publications in PubMed, Embase, and The Cochrane Library, with the last search performed March 23, 2016. Data on overall survival (OS), progression-free survival (PFS), and MGMT methylation status were obtained. RESULTS Data from 3 clinical trials for a total of 1443 subjects were used for this meta-analysis. MGMT methylated and unmethylated patients showed improved PFS in the BV group (pooled HRs, 0.769, 95% CIs 0.604-0.978, P=0.032; 0.675, 95%CIs 0.466-0.979, P=0.038). For patients with either type of GBM, BV did not improve the OS based on the pooled HRs 1.132 (95% CIs 0.876-1.462; P=0.345) for methylated and 1.018 (95% CIs 0.879-1.179; P=0.345) for unmethylated. CONCLUSIONS Bevacizumab combined with temozolomide-radiotherapy correlated with improved PFS for treatment of patients with different MGMT methylation status of newly diagnosed GBM. There was insufficient evidence to determine the synergistic effects of combining BV with TMZ and RT on improving survival in patients with different MGMT methylation status.

Blood-brain barrier, cytotoxic chemotherapies and glioblastoma

INTRODUCTION

Glioblastomas (GBM) are the most common and aggressive primary malignant brain tumors in adults. The blood brain barrier (BBB) is a major limitation reducing efficacy of anti-cancer drugs in the treatment of GBM patients. Areas covered: Virtually all GBM recur after the first-line treatment, at least partly, due to invasive tumor cells protected from chemotherapeutic agents by the intact BBB in the brain adjacent to tumor. The passage through the BBB, taken by antitumor drugs, is poorly and heterogeneously documented in the literature. In this review, we have focused our attention on: (i) the BBB, (ii) the passage of chemotherapeutic agents across the BBB and (iii) the strategies investigated to overcome this barrier. Expert commentary: A better preclinical knowledge of the crossing of the BBB by antitumor drugs will allow optimizing their clinical development, alone or combined with BBB bypassing strategies, towards an increased success rate of clinical trials.

The Role of a Single Angiogenesis Inhibitor in the Treatment of Recurrent Glioblastoma Multiforme: A Meta-Analysis and Systematic Review

BACKGROUND

Currently, the standard treatment for newly diagnosed glioblastoma multiforme (GBM) is maximal safe surgical resection followed by radiation therapy with concurrent and adjuvant temozolomide. However, disease recurs in almost all patients, and the optimal salvage treatment for recurrent GBM remains unclear. We conducted a systematic review and meta-analysis of published clinical trials to assess the efficacy and toxicities of angiogenesis inhibitors alone as salvage treatment in these patients.

METHODS

Trials published between 1994 and 2015 were identified by an electronic search of public databases (MEDLINE, EMBASE, Cochrane library). Demographic data, treatment regimens, objective response rate (ORR), median progression-free survival (PFS), median overall survival (OS), 6-months PFS rate, 1-year OS and grade 3/4 toxicities were extracted. We also compared the main outcomes of interest between bevacizumab and other angiogenesis inhibitors. All analyses were performed using Comprehensive Meta Analysis software (Version 2.0).

RESULTS

A total of 842 patients were included for analysis: 343 patients were treated with bevacizumab, 386 with other angiogenesis inhibitors and 81 with thalidomide. The pooled ORR, 6-months PFS, and 1-year OS for recurrent GBM patients receiving angiogenesis inhibitors was 20.1%, 19.5% and 29.3%, respectively. The use of single agent bevacizumab in recurrent GBM significantly improved ORR and 6-months PFS when compared to other angiogenesis inhibitors [relative risk (RR) 2.93, 95% CI 1.38-6.21; p = 0.025; and RR 2.36 95% CI 1.46-3.82; p<0.001, respectively], while no significant difference in 1-year OS was found between the two groups (p = 0.07). when compared to thalidomide, bevacizumab treatment in recurrent GBM significantly improved ORR (RR 6.8, 95%CI: 2.64-17.6, p<0.001), but not for 6-months PFS (p = 0.07) and 1-year OS (p = 0.31). As for grade 3/4 toxicities, the common toxicity was hypertension with pooled incidence of 12.1%, while high-grade thromboembolic events (2.2%), hemorrhage (5.1%) and GI perforation (2.8%) associated with angiogenesis inhibitors were relatively low.

CONCLUSIONS

In comparison with other angiogenesis inhibitors and thalidomide, the use of single agent bevacizumab as salvage treatment for recurrent GBM patients improve ORR and 6-months PFS, but not for 1-year OS.

Therapeutic options in recurrent glioblastoma--An update

INTRODUCTION

Standards of care are not yet defined in recurrent glioblastoma.

METHODS

We reviewed the literature on clinical trials for recurrent glioblastoma available in PubMed and American Society of Clinical Oncology (ASCO) abstracts until June 2015.

RESULTS

Evidence is limited due to the paucity of randomized controlled studies. Second surgery or re-irradiation are options for selected patients. Alkylating chemotherapy such as nitrosoureas or temozolomide and the vascular endothelial growth factor (VEGF) antibody, bevacizumab, exhibit comparable single agent activity. Phase III data exploring the benefit of combining bevacizumab and lomustine are emerging. Novel approaches in the fields of targeted therapy, immunotherapy, and tumor metabolism are coming forward. Several biomarkers are being explored, but, except for O(6)-methylguanine DNA methyltransferase (MGMT) promoter methylation, none has assumed a role in clinical practice.

CONCLUSION

Proper patient selection, development of predictive biomarkers and randomized controlled studies are required to develop evidence-based concepts for recurrent glioblastoma.

Adverse event grading following CTCAE v3.0 underestimates hypertensive side effects in patients with glioma treated with Bevacizumab

Anti-VEGF therapy with Bevacizumab (BEV) is widely used in cases of relapsed high-grade glioma (HGG). Arterial hypertension is a known side effect of anti-VEGF therapy. 42 Patients with relapsed HGG were treated with BEV 10 mg/kg on days 1 and 15 of 28-day cycles in addition to treatment with 40 mg TMZ daily until disease progression, based on magnetic resonance imaging and/or worsening of clinical status. In a retrospective analysis, hypertensive side effects were evaluated as the primary endpoint, while survival information in addition to toxicity was analyzed as secondary endpoint. Grading which employs the Common Terminology Criteria for Adverse Events (CTCAE) version 4.0 detected hypertensive events with a significantly higher sensitivity than CTCAE version 3.0. The rate of severe hypertensive events observed as CTCAE ≥ °3 were 9.5 % in version 3.0 and 45.2 % in version 4.0. The results presented here indicate that CTCAE version 3.0 may underreport the incidence and grade of BEV-induced hypertension within clinical trials. As hypertension has not only long-term, but also severe short-term side effects, we suggest that arterial hypertension under BEV should be scored according to CTCAE version 4.0 to avoid clinically relevant hypertension-related adverse events in these patients.

Efficacy and safety of bevacizumab for the treatment of glioblastoma

Glioblastoma (GBM) is the most common and devastating primary malignant intracranial tumor in adults. The current first-line treatment for patients with newly diagnosed GBM is surgical resection followed by radiotherapy plus concomitant and adjuvant temozolomide. This treatment protocol may prolong the survival period of the patient, however it is not curative and more effective therapeutic strategies are required. GBM is a type of highly vascularized tumor with increased expression levels of vascular endothelial growth factor (VEGF), which is a significant mediator of angiogenesis. Since angiogenesis is essential for tumor growth, anti-angiogenic therapies hold potential for the treatment of GBM, and targeting VEGF has demonstrated promising results in previous studies. Bevacizumab (BEV) is a recombinant humanized monoclonal antibody that inhibits VEGF and is approved by the US Food and Drug Administration as a monotherapy treatment for patients with recurrent GBM and is associated with manageable toxicity. Previous studies have demonstrated that BEV may be an effective treatment for recurrent GBM, with prolonged progression-free survival and overall survival, and maintained patient quality of life and functional status. The present review article briefly outlines the mechanism of action of BEV and summarizes the current literature and clinical trial research on the role of BEV for the treatment of patients with recurrent and newly diagnosed GBM.

Bevacizumab for glioblastoma

Individuals with glioblastoma are often characterized by older age, advanced neurologic manifestations at the primary stage, and unresectable tumors, and these factors are associated with poor treatment outcomes. Administration of bevacizumab (BV, Avastin^®) promotes tumor regression and improves cerebral edema, and is expected to improve neurologic findings in many patients with malignant gliomas, including glioblastoma. Although the addition of BV to the conventional standard therapy (chemoradiotherapy with temozolomide) for newly diagnosed glioblastoma prolonged the progression-free survival time and the performance status of patients, it failed to extend overall survival time. However, more than 50% of glioblastoma patients show Karnofsky performance status ≤70 at initial presentation; therefore, BV should be used to improve or maintain their performance status as an initial treatment. Most of the adverse events of BV, except hypertension and proteinuria, occur as complications of glioblastoma, and explanation of the advantages and disadvantages of BV administration to patients is important. Herein, the efficacy, safety, and challenges of using BV for treating glioblastoma were reviewed.

Novel chemotherapeutics and other therapies for treating high-grade glioma

INTRODUCTION

Despite extensive research, high-grade glioma (HGG) remains a dire diagnosis with no change in the standard of care in almost a decade. However, recent advancements uncovering molecular biomarkers of brain tumors and tumor-specific antigens targeted by immunotherapies provide opportunities for novel personalized treatment regimens to improve survival.

AREAS COVERED

In this review, the authors provide a comprehensive overview of recent therapeutic advancements in HGG. Furthermore, they describe new molecular biomarkers and molecular classifications, in addition to updated research on bevacizumab, targeted molecular therapies, immunotherapy and alternative delivery methods that overcome the blood-brain barrier to reach the target tumor tissue. Challenges regarding each therapy are also outlined. The authors also provide some insight into a novel non-chemotherapeutic treatment for malignant glioma, NovoTTFA, as well as a summary of current treatment options for recurrence.

EXPERT OPINION

Current research for treating malignant gliomas are paving the path to personalized therapy, including immunotherapy, that involve integrated genomic and histolopathologic data, as well as a multi-modal treatment regimen. Immunotherapy will potentially be the next addition to the current standard of care, specialized to the antigens presented on the tumors. The results of the current trials of multi-antigen vaccines are eagerly anticipated.

Glioblastoma multiforme: Pathogenesis and treatment

Each year, about 5-6 cases out of 100,000 people are diagnosed with primary malignant brain tumors, of which about 80% are malignant gliomas (MGs). Glioblastoma multiforme (GBM) accounts for more than half of MG cases. They are associated with high morbidity and mortality. Despite current multimodality treatment efforts including maximal surgical resection if feasible, followed by a combination of radiotherapy and/or chemotherapy, the median survival is short: only about 15months. A deeper understanding of the pathogenesis of these tumors has presented opportunities for newer therapies to evolve and an expectation of better control of this disease. Lately, efforts have been made to investigate tumor resistance, which results from complex alternate signaling pathways, the existence of glioma stem-cells, the influence of the blood-brain barrier as well as the expression of 0(6)-methylguanine-DNA methyltransferase. In this paper, we review up-to-date information on MGs treatment including current approaches, novel drug-delivering strategies, molecular targeted agents and immunomodulative treatments, and discuss future treatment perspectives.

Use of ERC-1671 Vaccine in a Patient with Recurrent Glioblastoma Multiforme after Progression during Bevacizumab Therapy: First Published Report

Glioblastoma multiforme is a highy aggressive tumor that recurs despite resection, focal beam radiation, and temozolamide chemotherapy. ERC-1671 is an experimental treatment strategy that uses the patient's own immune system to attack the tumor cells. The authors report preliminary data on the first human administration of ERC-1671 vaccination under a single-patient, compassionate-use protocol. The patient survived for ten months after the vaccine administration without any other adjuvant therapy and died of complications related to his previous chemotherapies.

The future of high-grade glioma: Where we are and where are we going

High-grade glioma (HGG) are optimally treated with maximum safe surgery, followed by radiotherapy (RT) and/or systemic chemotherapy (CT). Recently, the treatment of newly diagnosed anaplastic glioma (AG) has changed, particularly in patients with 1p19q codeleted tumors. Results of trials currenlty ongoing are likely to determine the best standard of care for patients with noncodeleted AG tumors. Trials in AG illustrate the importance of molecular characterization, which are germane to both prognosis and treatment. In contrast, efforts to improve the current standard of care of newly diagnosed glioblastoma (GB) with, for example, the addition of bevacizumab (BEV), have been largely disappointing and furthermore molecular characterization has not changed therapy except in elderly patients. Novel approaches, such as vaccine-based immunotherapy, for newly diagnosed GB are currently being pursued in multiple clinical trials. Recurrent disease, an event inevitable in nearly all patients with HGG, continues to be a challenge. Both recurrent GB and AG are managed in similar manner and when feasible re-resection is often suggested notwithstanding limited data to suggest benefit from repeat surgery. Occassional patients may be candidates for re-irradiation but again there is a paucity of data to commend this therapy and only a minority of selected patients are eligible for this approach. Consequently systemic therapy continues to be the most often utilized treatment in recurrent HGG. Choice of therapy, however, varies and revolves around re-challenge with temozolomide (TMZ), use of a nitrosourea (most often lomustine; CCNU) or BEV, the most frequently used angiogenic inhibitor. Nevertheless, no clear standard recommendation regarding the prefered agent or combination of agents is avaliable. Prognosis after progression of a HGG remains poor, with an unmet need to improve therapy.

Single-agent bevacizumab is an effective treatment in recurrent glioblastoma

The aim of this study was to evaluate the efficiency and safety of single-agent bevacizumab therapy for recurrent glioblastoma multiforme (GBM). We identified patients with histologically confirmed glioblastoma and World Health Organization Grade III glioma who were previously treated with temozolomide plus radiotherapy and received 10 mg/kg bevacizumab intravenous infusion every 2 weeks until disease progression for recurrent disease. A total 24 patients included to this study. Twenty-two patients had GBM, and two patients had WHO grade III glioma. No complete response was observed, five patients (20.8 %) had partial response, nine patients (37.5 %) had stable diseases, and ten patients (41.7 %) had progressive diseases. The overall response rate was 20.8 %. The 6-month PFS rate (PFS6) and median PFS were determined as 37.5 % and 4.1 months, respectively. Median OS was 6.4 months. Performance status of 17 (70.8 %) patients was improved following bevacizumab regimen. Univariate analysis showed that improvement in performance status (IPS) following bevacizumab therapy was a significant predictor of both PFS (p < 0.001) and OS (p < 0.020). Bevacizumab-related adverse effects were observed in 13 (54.1 %) patients. Grade 3-4 toxicity was observed in 4 (16.6 %) patients. Therapy interruptions were experienced in two patients due to adverse effects. Single-agent bevacizumab is an effective and safe treatment alternative in recurrent GBM. IPS following bevacizumab therapy was a significant predictor of both PFS and OS.

Incorporation of biomarkers in phase II studies of recurrent glioblastoma

The survival trends for glioblastoma (GBM) patients have remained largely static, reflecting a lack of improvement in the therapeutic options for patients. Less than 5 % of newly diagnosed GBM survives more than 5 years. Tumor relapse is nearly universal and the majority of patients do not respond to further systemic therapy. The results from phase II studies conducted with recurrent GBM patients have not translated to successful confirmatory studies and thus we have reached a significant roadblock in the development of new treatments for patients with recurrent GBM. The development of new, active, and potentially targeted drugs for the treatment of recurrent GBM represents a major unmet need. The incorporation of diagnostic/companion biomarker combinations into the phase II studies and appropriate stratification of the patients is lagging significantly behind other larger cancer groups such as breast, non-small cell lung cancer, and melanoma. We herein carried out a systematic review of the phase II clinical studies conducted in patients with recurrent GBM (2010-2013 inclusive) to assess the degree of biomarker incorporation within the clinical trial design.