Salvage therapy with single agent bendamustine for recurrent glioblastoma

Lipid-Based Nanocarriers in the Treatment of Glioblastoma Multiforme (GBM): Challenges and Opportunities

Glioblastoma multiforme (also known as glioblastoma; GBM) is one of the most malignant types of brain tumors that occurs in the CNS. Treatment strategies for glioblastoma are majorly comprised of surgical resection, radiotherapy, and chemotherapy along with combination therapy. Treatment of GBM is itself a tedious task but the involved barriers in GBM are one of the main impediments to move one step closer to the treatment of GBM. Basically, two of the barriers are of utmost importance in this regard, namely blood brain barrier (BBB) and blood brain tumor barrier (BBTB). This review will address different challenges and barriers in the treatment of GBM along with their etiology. The role and recent progress of lipid-based nanocarriers like liposomes, solid lipid nanocarriers (SLNs), nanostructured lipid carriers (NLCs), lipoplexes, and lipid hybrid carriers in the effective management of GBM will be discussed in detail.

Evaluation of two-stage designs of Phase 2 single-arm trials in glioblastoma: a systematic review

BACKGROUND

Due to economical and ethical reasons, the two-stage designs have been widely used for Phase 2 single-arm trials in oncology because the designs allow us to stop the trial early if the proposed treatment is likely to be ineffective. Nonetheless, none has examined the usage for published articles that had applied the two-stage designs in Phase 2 single-arm trials in brain tumor. A complete systematic review and discussions for overcoming design issues might be important to better understand why oncology trials have shown low success rates in early phase trials.

METHODS

We systematically reviewed published single-arm two-stage Phase 2 trials for patients with glioblastoma and high-grade gliomas (including newly diagnosed or recurrent). We also sought to understand how these two-stage trials have been implemented and discussed potential design issues which we hope will be helpful for investigators who work with Phase 2 clinical trials in rare and high-risk cancer studies including Neuro-Oncology. The systematic review was performed based on the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA)-statement. Searches were conducted using the electronic database of PubMed, Google Scholar and ClinicalTrials.gov for potentially eligible publications from inception by two independent researchers up to May 26, 2022. The followings were key words for the literature search as index terms or free-text words: "phase II trials", "glioblastoma", and "two-stage design". We extracted disease type and setting, population, therapeutic drug, primary endpoint, input parameters and sample size results from two-stage designs, and historical control reference, and study termination status.

RESULTS

Among examined 29 trials, 12 trials (41%) appropriately provided key input parameters and sample size results from two-stage design implementation. Among appropriately implemented 12 trials, discouragingly only 3 trials (10%) explained the reference information of historical control rates. Most trials (90%) used Simon's two-stage designs. Only three studies have been completed for both stages and two out of the three completed studies had shown the efficacy.

CONCLUSIONS

Right implementation for two-stage design and sample size calculation, transparency of historical control and experimental rates, appropriate selection on primary endpoint, potential incorporation of adaptive designs, and utilization of Phase 0 paradigm might help overcoming the challenges on glioblastoma therapeutic trials in Phase 2 trials.

Retrospective Study of the Safety and Efficacy of Anlotinib Combined With Dose-Dense Temozolomide in Patients With Recurrent Glioblastoma

Purpose

The purpose of this study was to retrospectively analyze the safety and clinical efficacy of anlotinib combined with dose-dense temozolomide (TMZ) as the first-line therapy in the treatment of recurrent glioblastoma (rGBM).

Patients and Methods

We collected the clinical data of 20 patients with rGBM. All patients received anlotinib (12 mg daily, orally for 2 weeks, discontinued for 1 week, repeated every 3 weeks) combined with dose-dense TMZ (100 mg/m², 7 days on with 7 days off) until the disease progressed (PD) or adverse effects (AEs) above grade 4 appeared. Grade 3 AEs need to be restored to grade 2 before continuing treatment, and the daily dose of anlotinib is reduced to 10 mg. The patients were reexamined by head magnetic resonance imaging (MRI) every 1 to 3 months. The therapeutic effect was evaluated according to Response Assessment in Neuro-Oncology (RANO) criteria. The survival rate was analyzed by Kaplan-Meier survival curve analysis. The baseline of all survival index statistics was the start of anlotinib combined with dose-dense of TMZ. National Cancer Institute-Common Terminology Criteria Adverse Events version 4.0 (NCI-CTCAE 4.0) was used to evaluate AEs.

Results

Twenty cases of rGBM were evaluated according to the RANO criteria after treatment with anlotinib and dose-dense TMZ, including five cases of stable disease (SD), thirteen cases of partial response (PR), one case of complete response (CR), and one case of PD. The median follow-up time was 13.4 (95% CI, 10.5–16.3) months. The 1-year overall survival (OS) rate was 47.7%. The 6-month progression-free survival (PFS) rate was 55%. In the IDH wild type group, the median PFS and median OS were 6.1 and 11.9 months, respectively. We observed that AEs associated with treatment were tolerable. One patient stopped taking the drug because of cerebral infarction. There were no treatment-related deaths.

Conclusion

Anlotinib combined with dose-dense TMZ for the first-line therapy showed good efficacy in OS, PFS, ORR, and DCR in the treatment of rGBM, and the AEs were tolerant. Randomized controlled clinical trials investigating the treatment of rGBM with anlotinib are necessary.

Intracranial Involvement in Multiple Myeloma Presenting as a Cranial Nerve Palsy

Multiple myeloma (MM) is characterized by the neoplastic proliferation of plasma cells producing a monoclonal immunoglobulin. Neurological complications in MM most frequently occur due to spinal cord compression by bony lesions, paraprotein-related neuropathy, hypercalcemia, hyperviscosity, or amyloidosis. Intracranial involvement is a rare complication of MM occurring in only 1% of patients. It can manifest as a solitary cerebral lesion, intra-parenchymal infiltration, or diffuse leptomeningeal disease. We present a case of a leptomeningeal myeloma in a 71-year-old woman with known relapsed MM presenting with a right sixth nerve palsy. Our patient was receiving spinal irradiation for a paraspinal plasmacytoma when she complained of double vision. Clinical exam revealed a right sixth nerve palsy. MRI revealed diffuse abnormal leptomeningeal thickening and enhancement typical for diffuse leptomeningeal infiltration. She was treated with whole brain irradiation and intrathecal methotrexate combined with a lenalidomide and dexamethasone chemotherapeutic regimen but unfortunately she passed away 5 weeks after onset of visual symptoms. MM involving the central nervous system (CNS) is a rare complication of MM and carries a poor prognosis with an average survival of 3 months. Due to its rarity, treatment of CNS MM is very heterogeneous. Thus case reporting is important to accumulate data on this rare presentation.

Clinical response and pharmacokinetics of bendamustine as a component of salvage R-B(O)AD therapy for the treatment of primary central nervous system lymphoma (PCNSL)

Background

A relatively high proportion of patients diagnosed with primary CNS lymphoma will experience recurrent disease, yet therapy options are limited in salvage therapy. This is the first study to evaluate a bendamustine-based combination regimen for the treatment of relapsed/refractory PCNSL and to characterize bendamustine pharmacokinetics in the human CSF.

Methods

Patients received bendamustine 75 mg/m² for two days as part of R-B(O)AD administered intravenously every 4 weeks for up to 4 cycles. Response and adverse events of the regimen were assessed. A sparse sampling strategy and population based modeling approach was utilized for evaluation of plasma and CSF levels of bendamustine.

Results

Ten patients were enrolled into study of whom 70% were of refractory disease and with high IELSG prognostic risk scores. The ORR of R-BOAD was 50% (95% CI, 0.24 to 0.76) with one patient achieving CR and four PR. Primary toxicity of the regimen was reversible myelosuppression, mostly grade 3 or 4 neutropenia. The C_max mean for plasma and CSF were 2669 ng/mL and 0.397 ng/mL, respectively, and patients with response at deep tumor sites displayed higher trends in peak exposure. Pharmacokinetic data was best described by a four-compartment model with first-order elimination of drug from central plasma and CSF compartments.

Conclusions

R-BOAD is an effective salvage option for PCNSL, but with significant hematologic toxicity. Bendamustine CSF levels are minimal; however correspond to plasma exposure and response.

Trial registration

ClinicalTrials.gov NCT03392714; retrospectively registered January 8, 2018.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4632-y) contains supplementary material, which is available to authorized users.

Retrospective study of nivolumab for patients with recurrent high grade gliomas

INTRODUCTION

Patients with recurrent high-grade gliomas (HGG) have limited treatment options. HGG utilize the PD-1 pathway to evade immune responses. Checkpoint inhibitors have demonstrated safety and clinical activity in patients with recurrent glioblastoma. We explored the efficacy of nivolumab in recurrent HGG with a primary objective of progression free survival (PFS) and overall survival (OS).

METHODS

We retrospectively analyzed HGG patients treated with nivolumab in our institution. We included patients with advanced HGG who received nivolumab at their oncologist's decision. Patients received nivolumab 3 mg/kg every 2 weeks until confirmed progression, intolerable toxicity, death, or physician decision. Radiographic assessments were performed every 8 weeks.

RESULTS

Between April 2015 and October 2017, 50 HGG patients received nivolumab. 43 patients received nivolumab with bevacizumab. 44 patients were bevacizumab refractory and 7 patients received nivolumab monotherapy. All had received prior radiation and chemotherapy. 39 adverse events (AEs) were noted [most commonly fatigue (16%) and constipation (10%)]. 4 (8%) patients experienced grade 3-4 AEs. 36 (72%) patients experienced stable disease (SD) at the 2-month assessment. Median duration of SD was 4.3 months (5.1 months in the bevacizumab naïve, 3.8 months in the bevacizumab refractory). Median PFS was 4.3 months (95% CI 3.5-5.3); median OS was 6.5 months (95% CI 6.0-8.8).

CONCLUSION

Treatment with nivolumab therapy was associated with a manageable safety profile. In a subset of patients, there was disease stabilization in heavily pre-treated recurrent HGG.

The first-in-class alkylating deacetylase inhibitor molecule tinostamustine shows antitumor effects and is synergistic with radiotherapy in preclinical models of glioblastoma

Background

The use of alkylating agents such as temozolomide in association with radiotherapy (RT) is the therapeutic standard of glioblastoma (GBM). This regimen modestly prolongs overall survival, also if, in light of the still dismal prognosis, further improvements are desperately needed, especially in the patients with O6-methylguanine-DNA-methyltransferase (MGMT) unmethylated tumors, in which the benefit of standard treatment is less. Tinostamustine (EDO-S101) is a first-in-class alkylating deacetylase inhibitor (AK-DACi) molecule that fuses the DNA damaging effect of bendamustine with the fully functional pan-histone deacetylase (HDAC) inhibitor, vorinostat, in a completely new chemical entity.

Methods

Tinostamustine has been tested in models of GBM by using 13 GBM cell lines and seven patient-derived GBM proliferating/stem cell lines in vitro. U87MG and U251MG (MGMT negative), as well as T98G (MGMT positive), were subcutaneously injected in nude mice, whereas luciferase positive U251MG cells and patient-derived GBM stem cell line (CSCs-5) were evaluated the orthotopic intra-brain in vivo experiments.

Results

We demonstrated that tinostamustine possesses stronger antiproliferative and pro-apoptotic effects than those observed for vorinostat and bendamustine alone and similar to their combination and irrespective of MGMT expression. In addition, we observed a stronger radio-sensitization of single treatment and temozolomide used as control due to reduced expression and increased time of disappearance of γH2AX indicative of reduced signal and DNA repair. This was associated with higher caspase-3 activation and reduction of RT-mediated autophagy. In vivo, tinostamustine increased time-to-progression (TTP) and this was additive/synergistic to RT. Tinostamustine had significant therapeutic activity with suppression of tumor growth and prolongation of DFS (disease-free survival) and OS (overall survival) in orthotopic intra-brain models that was superior to bendamustine, RT and temozolomide and showing stronger radio sensitivity.

Conclusions

Our data suggest that tinostamustine deserves further investigation in patients with glioblastoma.

Electronic supplementary material

The online version of this article (10.1186/s13045-018-0576-6) contains supplementary material, which is available to authorized users.

Prolonged survival in patients with breast cancer and a history of brain metastases: results of a preplanned subgroup analysis from the randomized phase III BEACON trial

Purpose

Conventional chemotherapy has limited activity in patients with breast cancer and brain metastases (BCBM). Etirinotecan pegol (EP), a novel long-acting topoisomerase-1 inhibitor, was designed using advanced polymer technology to preferentially accumulate in tumor tissue including brain metastases, providing sustained cytotoxic SN38 levels.

Methods

The phase 3 BEACON trial enrolled 852 women with heavily pretreated locally recurrent or metastatic breast cancer between 2011 and 2013. BEACON compared EP with treatment of physician’s choice (TPC; eribulin, vinorelbine, gemcitabine, nab-paclitaxel, paclitaxel, ixabepilone, or docetaxel) in patients previously treated with anthracycline, taxane, and capecitabine, including those with treated, stable brain metastases. The primary endpoint, overall survival (OS), was assessed in a pre-defined subgroup of BCBM patients; an exploratory post hoc analysis adjusting for the diagnosis-specific graded prognostic assessment (GPA) index was also conducted.

Results

In the trial, 67 BCBM patients were randomized (EP, n = 36; TPC, n = 31). Treatment subgroups were balanced for baseline characteristics and GPA indices. EP was associated with a significant reduction in the risk of death (HR 0.51; P < 0.01) versus TPC; median OS was 10.0 and 4.8 months, respectively. Improvement in OS was observed in both poorer and better GPA prognostic groups. Survival rates at 12 months were 44.4% for EP versus 19.4% for TPC. Consistent with the overall BEACON population, fewer patients on EP experienced grade ≥3 toxicity (50 vs. 70%).

Conclusions

The significant improvement in survival in BCBM patients provides encouraging data for EP in this difficult-to-treat subgroup of patients. A phase three trial of EP in BCBM patients is underway (ClinicalTrials.gov NCT02915744).

Electronic supplementary material

The online version of this article (doi:10.1007/s10549-017-4304-7) contains supplementary material, which is available to authorized users.

Nivolumab for patients with recurrent glioblastoma progressing on bevacizumab: a retrospective case series

A single institution retrospective evaluation of nivolumab following disease progression on bevacizumab in adults with recurrent glioblastoma (GBM) with an objective of determining progression free survival (PFS). There is no accepted therapy for recurrent GBM after failure of bevacizumab. 16 adults, ages 52-72 years (median 62), with recurrent GBM were treated. All patients had previously been treated with surgery, concurrent radiotherapy and temozolomide, and post-radiotherapy temozolomide. Bevacizumab (with or without lomustine) was administered to all patients at first recurrence. Patients were treated with nivolumab only (3 mg/kg) once every 2 weeks at second recurrence. One cycle of nivolumab was defined as 2 treatments. Neurological evaluation was performed bi-weekly and neuroradiographic assessment every 4 weeks. A total of 37 treatment cycles (median 2) were administered of nivolumab in which there were 14 Grade 2 adverse events (AEs) and Grade 3 AEs in two patients. No Grade 4 or 5 AEs were seen. Following 1 month of nivolumab, seven patients demonstrated progressive disease and discontinued therapy. No patient demonstrated a response though nine patients demonstrated neuroradiographic stable response. Survival in the entire cohort ranged from 2 to 6 months with a median of 3.5 months (CI 2.8, 4.2). Median and 6-month PFS at 6 months was 2.0 months (range 1-5 months; CI 1.3, 2.7) and 0% respectively. Nivolumab salvage therapy demonstrated no survival advantage in patients with recurrent bevacizumab refractory GBM emphasizing a continued unmet need in neuro-oncology.

First clinical results of a personalized immunotherapeutic vaccine against recurrent, incompletely resected, treatment-resistant glioblastoma multiforme (GBM) tumors, based on combined allo- and auto-immune tumor reactivity

Glioblastoma multiforme (GBM) patients have a poor prognosis. After tumor recurrence statistics suggest an imminent death within 1-4.5 months. Supportive preclinical data, from a rat model, provided the rational for a prototype clinical vaccine preparation, named Gliovac (or ERC 1671) composed of autologous antigens, derived from the patient's surgically removed tumor tissue, which is administered together with allogeneic antigens from glioma tissue resected from other GBM patients. We now report the first results of the Gliovac treatment for treatment-resistant GBM patients. Nine (9) recurrent GBM patients, after standard of care treatment, including surgery radio- and chemotherapy temozolomide, and for US patients, also bevacizumab (Avastin™), were treated under a compassionate use/hospital exemption protocol. Gliovac was given intradermally, together with human GM-CSF (Leukine(®)), and preceded by a regimen of regulatory T cell-depleting, low-dose cyclophosphamide. Gliovac administration in patients that have failed standard of care therapies showed minimal toxicity and enhanced overall survival (OS). Six-month (26 weeks) survival for the nine Gliovac patients was 100% versus 33% in control group. At week 40, the published overall survival was 10% if recurrent, reoperated patients were not treated. In the Gliovac treated group, the survival at 40 weeks was 77%. Our data suggest that Gliovac has low toxicity and a promising efficacy. A phase II trial has recently been initiated in recurrent, bevacizumab naïve GBM patients (NCT01903330).

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.

Current and investigational drug strategies for glioblastoma

Medical treatments for glioblastoma face several challenges. Lipophilic alkylators remain the mainstay of treatment, emphasising the primacy of good blood-brain barrier penetration. Temozolomide has emerged as a major contributor to improved patient survival. The roles of procarbazine and vincristine in the procarbazine, lomustine and vincristine (PCV) schedule have attracted scrutiny and several lines of evidence now support the use of lomustine as effective single-agent therapy. Bevacizumab has had a convoluted development history, but clearly now has no major role in first-line treatment, and may even be detrimental to quality of life in this setting. In later disease, clinically meaningful benefits are achievable in some patients, but more impressively the combination of bevacizumab and lomustine shows early promise. Over the last decade, investigational strategies in glioblastoma have largely subscribed to the targeted kinase inhibitor paradigm and have mostly failed. Low prevalence dominant driver lesions such as the FGFR-TACC fusion may represent a niche role for this agent class. Immunological, metabolic and radiosensitising approaches are being pursued and offer more generalised efficacy. Finally, trial design is a crucial consideration. Progress in clinical glioblastoma research would be greatly facilitated by improved methodologies incorporating: (i) routine pharmacokinetic and pharmacodynamic assessments by preoperative dosing; and (ii) multi-stage, multi-arm protocols incorporating new therapy approaches and high-resolution biology in order to guide necessary improvements in science.

Salvage therapy with bendamustine for methotrexate refractory recurrent primary CNS lymphoma: a retrospective case series

There is comparatively limited therapy for recurrent primary central nervous system lymphoma (PCNSL). Salvage therapies include re-challenge with high-dose methotrexate (HD-MTX), whole brain radiotherapy, temozolomide, topotecan and premetrexed. Bendamustine is a novel bifunctional alkylator with established activity in B cell systemic lymphomas but never previously evaluated in PCNSL. The objective of the current study was to assess response and toxicity of bendamustine in recurrent PCNSL following prior salvage therapy in a retrospective case series. Twelve adults [six males; six females: median age 59 years (range 43-74)] with HD-MTX refractory recurrent PCNSL were treated with bendamustine. All patients were treated at second recurrence following failure of prior salvage therapy. A cycle of bendamustine was defined as two consecutive days of treatment (100 mg/m(2)/day) administered once every 4 weeks (maximum number of cycles 6). Toxicities seen were Grade 2 (24 episodes in 10 patients) and 3 (10 episodes in 5 patients) only and included lymphopenia (8 patients), hyperglycemia (7 patients), fatigue (7 patients) and nausea (4 patients). The median number of cycles of therapy was 3.5 (range 1-6). Radiographic response was progressive disease in 5 (42%), stable disease in 1 (8%), partial response in 3 (25%) and complete response in 3 (25%). Median progression free survival (PFS) was 3.5 months (range 1-14 months) and 6-month PFS was 33 %. In this small retrospective series of select patients with recurrent PCNSL refractory to HD-MTX, bendamustine appears to have modest single agent activity with manageable toxicity. Confirmation in a larger series of similar patients is required.

Role for cytotoxic chemotherapy in patients with recurrent glioblastoma progressing on bevacizumab: a retrospective case series

One hundred patients, aged 36-84 years (median 62 years) with recurrent glioblastoma (GBM), were treated previously with surgery, concurrent radiotherapy and temozolomide and postradiotherapy temozolomide followed by single-agent bevacizumab (BEV) at either first (60 patients) or second recurrence (40 patients). Patients were then treated following progression on BEV only with BEV and carboplatin (75 patients), cyclophosphamide (15 patients) or BCNU (ten patients; BEV+). Three hundred and sixteen treatment cycles (median: 2; range: 1-9) were administered of BEV+. There were 74 grade 3 adverse events in 29 patients (29%) and 20 grade 4 adverse events in ten patients (10%). Following 2 months of BEV+, 60 patients (60%) demonstrated progressive disease and discontinued therapy. Forty patients (40%) had neuroradiographic stable disease. Survival ranged from 1 to 12 months (median: 4 months). Median and 6-month progression free survival was 2.5 months and 5%, respectively. BEV plus a cytotoxic chemotherapy demonstrated limited efficacy in BEV-refractory GBM and emphasizes an unmet need in neuro-oncology in adults with BEV-refractory GBM.

State of the art and perspectives in the treatment of glioblastoma

Glioblastoma is the most common malignant primary brain tumor. Cures are rare and median survival varies from several to 22 months. Standard treatment for good performance patients consists of maximal safe surgical resection followed by radiotherapy with concurrent temozolomide (TMZ) chemotherapy and six cycles of postradiotherapy TMZ. At recurrence, treatment options include repeat surgery (with or without Gliadel wafer placement), reirradiation or systemic therapy. Most patients with good performance status are treated with cytotoxic chemotherapy or targeted biologic therapy following or in lieu of repeat surgery. Cytotoxic chemotherapy options include nitrosoureas, rechallenge with TMZ, platins, phophoramides and topoisomerase inhibitors, although efficacy is limited. Despite the intense effort of developing biologic agents that target angiogenesis and growth and proliferative pathways, bevacizumab is the only agent that has shown efficacy in clinical trials. It was awarded accelerated approval in the USA after demonstrating an impressive radiographic response in two open-label, prospective Phase II studies. Two randomized, Phase III trials of upfront bevacizumab have completed and may demonstrate survival benefit; however, results are pending at this time. Given the limited treatment options at tumor recurrence, consideration for enrollment on a clinical trial is encouraged.