Deferred use of bevacizumab for recurrent glioblastoma is not associated with diminished efficacy

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.

Clinical Outcome of Cytoreductive Surgery Prior to Bevacizumab for Patients with Recurrent Glioblastoma: A Single-center Retrospective Analysis

Bevacizumab (BEV) is a key anti-angiogenic agent used in the treatment for recurrent glioblastoma multiforme (GBM). The aim of this study was to investigate whether cytoreductive surgery prior to treatment with BEV contributes to prolongation of survival for patients with recurrent GBM. We retrospectively analyzed the treatment outcomes of 124 patients with recurrent GBM who were initially treated with the Stupp protocol between 2006 and 2019. Given that BEV has only been available in Japan since 2013, we grouped the patients into two groups according to the time of first recurrence: the pre-BEV group (N = 51) included patients who had recurrence before BEV approval, and the BEV group (N = 73) included patients with recurrence after BEV approval. The overall survival after first recurrence (OS-R) was analyzed according to the treatment strategy. Among 124 patients, 27 patients (19.4%) received cytoreductive surgery. There were nine cases in the pre-BEV group and 18 cases in the BEV group. Although the mean extent of resection for both groups was almost equal, OS-R was significantly different. The median OS-R was 8.1 m in the pre-BEV group and 16.3 m in the BEV group (P = 0.007). Multivariate analysis revealed that the unavailability of BEV postoperatively (P = 0.03) and decreasing performance status by surgery (P = 0.01) were significant poor prognostic factors for survival after surgery. With the advent of BEV, cytoreductive surgery might provide superior survival benefit at the time of GBM recurrence, especially in cases where surgery can be performed without deteriorating the patient's condition.

Strategies to better treat glioblastoma: antiangiogenic agents and endothelial cell targeting agents

Glioblastoma multiforme (GBM) is the most prevalent and aggressive form of glioma, with poor prognosis and high mortality rates. As GBM is a highly vascularized cancer, antiangiogenic therapies to halt or minimize the rate of tumor growth are critical to improving treatment. In this review, antiangiogenic therapies, including small-molecule drugs, nucleic acids and proteins and peptides, are discussed. The authors further explore biomaterials that have been utilized to increase the bioavailability and bioactivity of antiangiogenic factors for better antitumor responses in GBM. Finally, the authors summarize the current status of biomaterial-based targeting moieties that target endothelial cells in GBM to more efficiently deliver therapeutics to these cells and avoid off-target cell or organ side effects.

Bevacizumab versus alkylating chemotherapy in recurrent glioblastoma

BACKGROUND

The use of alkylating chemotherapy versus bevacizumab for recurrent glioblastoma remains controversial. Here, we tested the hypothesis that the activity of alkylators, but not that of bevacizumab, would be associated with the O⁶-methylguanine DNA methyltransferase (MGMT) promoter methylation status.

METHODS

We analyzed a cohort of patients treated at centers of the German Glioma Network or the University Hospital Zurich with alkylating agent-based chemotherapy (n = 260) or bevacizumab without or with irinotecan (n = 84) for first recurrence of glioblastoma. Outcome was stratified for O⁶-methylguanine DNA methyltransferase (MGMT) status and crossover to bevacizumab or alkylators at further progression.

RESULTS

Median post-recurrence survival-1 (PRS-1) for patients receiving alkylating agents at first recurrence was longer than with bevacizumab (11.1 versus 7.4 months, p < 0.001). The use of alkylators was associated with longer PRS-1 for patients with a methylated versus unmethylated MGMT promoter (p = 0.017). For patients receiving bevacizumab, PRS-1 was not different with or without MGMT promoter methylation. PRS-1 was longer in patients receiving alkylating chemotherapy compared to bevacizumab for patients with methylated (p < 0.001) or unmethylated MGMT promoter (p = 0.034). For patients with alkylators at first recurrence receiving bevacizumab at any further recurrence, PRS-1 was longer than in patients receiving bevacizumab first and alkylators thereafter (p = 0.002).

CONCLUSIONS

This study confirms limited value of bevacizumab in recurrent glioblastoma independent of MGMT status. Alkylating agents have activity in recurrent glioblastoma, especially in the context of MGMT promoter methylation.

Long-term survival in patients with recurrent glioblastoma treated with bevacizumab: a multicentric retrospective study

PURPOSE

Recurrence of glioblastoma (GB) occurs in most patients after standard concomitant temozolomide-based radiochemotherapy (CTRC). Bevacizumab (BV), an anti-VEGF antibody, has an effect on progression-free survival (PFS) but not on overall survival (OS). However, a small part of the patients experience a survival, longer than expected. This retrospective study aims to characterize long responder (LR) patients treated with BV for a first or second GBM recurrence.

METHODS

Medical records from patients (814) who received BV for a first or second recurrence of primary glioblastoma between September 2010 and September 2015, and initially treated by CTRC were analyzed. Patients, who had at least a stable disease according to RANO criteria at 12 months from the start of BV, were included. Patients who had, a secondary GB, or received BV in neoadjuvant or adjuvant setting were excluded.

RESULTS

We focused on 65 LR patients without progression 12 months after the first injection of BV (8%). Median PFS was 21.7 months [95% CI (19.3; 27.2)] and median OS was 31.1 months [95% CI (24.3; 37.5)] from the start of BV. No prognostic factor was associated with OS in multivariate analysis. Karnofsky performance status, neurological status and corticosteroid dose were stable at 12 months.

CONCLUSIONS

Our results highlight that among patients receiving bevacizumab in first or second recurrence, one patient out of twelve could be classified as LR. A median OS of 31.1 months from the start of BV could be expected in this subpopulation. These findings reinforce the potential benefit of the use of BV in the situation of recurrence. 256 words.

Patterns of long-term survivorship following bevacizumab treatment for recurrent glioma: a case series

Aim:

Long-term survivors (LTS) after glioma recurrence while on bevacizumab (Bev) therapy are rarely reported in the current literature. The purpose of this case series is to confirm the existence of and describe a large cohort of recurrent glioma LTS treated with Bev (Bev-LTS).

Patients & methods:

We identified Bev-LTS as patients with post-Bev initiation survival times of ≥3 years among 1397 Bev treated recurrent glioma patients.

Results:

Among 962 grade-IV, 221 grade III, and 214 grade II Bev-treated glioma patients, we identified 28 (2.9%), 14 (6.3%) and 8 (3.7%) Bev-LTS patients, respectively. 45 Bev-LTS patients recurred on Bev, with 36 of those patients continuing therapy.

Conclusion:

Our study shows that a small portion of grade-IV, -III, and -II glioma patients can have long-term survival on Bev therapy even after Bev recurrence.

Multimodal treatment for local recurrent malignant gliomas: Resurgery and/or reirradiation followed by chemotherapy

The therapeutic management of recurrent malignant gliomas (MGs) is not determined. Therefore, the efficacy of a multimodal approach and a combination systemic therapy was investigated. A retrospective analysis of 26 MGs patients at first relapse treated with multimodal therapy (chemotherapy plus surgery and/or reirradiation) or chemotherapy alone was performed. Second-line chemotherapy consisted of fotemustine (FTM) in combination with bevacizumab (BEV) (cFTM/BEV) or followed by third-line BEV (sFTM/BEV). Subgroup analyses were performed. Multimodal therapy provided a higher overall response rate (ORR) (73 vs. 47%), disease control rate (DCR) (82 vs. 67%), median progression-free survival (mPFS) (11 vs. 7 months; P=0.08) and median overall survival (mOS) (13 vs. 8 months; P=0.04) compared with chemotherapy. Concomitant FTM/BEV resulted in higher ORR (84 vs. 36%), DCR (92 vs. 57%), mPFS (10 vs. 5 months; P=0.22) and mOS (11 vs. 5.2 months; P=0.15) compared with sFTM/BEV. Methylated patients did not experience additional survival benefits with multimodality treatment but had higher mPFS (10 vs 7.1 months; P=0.33) and mOS (11 vs. 8 months; P=0.33) with cFTM/BEV. Unmethylated patients experienced the greatest survival benefit with the multimodal approach (mPFS: 10 vs. 5 months; mOS 11 vs 6 months; both P=0.02) and cFTM/BEV (mPFS: 5 vs. 2 months; mOS 6 vs. 3.2 months; both P=0.01). In conclusion, in recurrent MGs, multimodal therapy and cFTM/BEV provide survival and response benefits. Methylated patients benefit from a cFTM/BEV but not from a multimodal approach. Notably, unmethylated patients had the highest survival benefit with the two strategies.

Dose-dense temozolomide for recurrent high-grade gliomas: a single-center retrospective study

There are limited treatment modalities after high-grade gliomas recurrence. MGMT depletion modulated by dose-dense temozolomide (ddTMZ) remains a debated therapy for initial TMZ responders. Patients were selected retrospectively from our practice with diagnosis of high-grade gliomas (WHO grade III or IV), and were followed since the start of ddTMZ until death or change of therapy. Twenty-one patients were reviewed, with a median age of 47 (25-61) years and a median of 5.8 (1.5-38.8) cycles of ddTMZ. The majority were males (71.4%). Sixty-six percent received 21 on/28 off ddTMZ schedule, 28.6% daily, and 1 patient received a 7 days on/7 days off schedule. IDH mutation status was available for 18 (85.7%) patients, with 7 (33.3%) IDH mutant and 11 (52.5%) IDH wild type. MGMT methylation was assessed in 6 (28.6%) of the patients, being MGMT methylated in 3 (14.3%) patients, and non-methylated in 3 (14.3%) patients. The majority of patients (57.1%) were receiving ddTMZ in addition to other forms of therapy, including either bevacizumab (38.1%) or tumor-treating fields (TTFields) (19.1%). Overall ddTMZ was well tolerated, with few adverse events reported. The estimated median overall survival after ddTMZ start was 11 months. Median progression-free survival (PFS) was 6 months. Outcomes did not vary between patients receiving ddTMZ alone or those using TTFields or bevacizumab as concomitant therapy, but there was a trend to longer survival with the use of concomitant TTFields. Our results demonstrate benefit of ddTMZ after previous treatment with standard TMZ dosing with no apparent increase in treatment-related toxicities. In summary, ddTMZ should be considered in TMZ responsive patients and warrants further investigation.

Effectiveness of lomustine and bevacizumab in progressive glioblastoma: a meta-analysis

Background

Glioblastomas (GBMs) are the most aggressive type of glial brain tumors. Despite aggressive treatment with surgery and chemoradiation, GBMs invariably relapse and tumors are progressive. Controversy remains on optimal treatment of patients with recurrent GBMs. Data from previous trials have suggested that the addition of bevacizumab (BEV) to lomustine (CCNU) might improve overall survival (OS) as compared with that with monotherapies. The aim of this study was to compare the efficacy of BEV in addition to CCNU versus single-agent therapy in patients with recurrent GBM.

Methods

Electronic databases were searched for eligible literature updated in December 2017. Trials assessing the effectiveness of CCNU and BEV in progressive GBM were included, of which the main outcomes were progression-free survival (PFS) and OS. All the data were pooled with the corresponding 95% confidence intervals (CIs) using RevMan software. Sensitivity and heterogeneity were quantitatively evaluated.

Results

Three randomized clinical trials were identified, including 574 patients (combination group: 358, monotherapies group: 216). The combination group treated with BEV and CCNU showed improvement in PFS (OR = 0.49; 95% CI, 0.41–0.59; p < 0.00001). No significant differences were, however, found in patients in terms of the OS (OR = 0.84; 95% CI, 0.68–1.03; p = 0.09).

Conclusion

Although treatment with CCNU plus BEV prolonged PFS, it did not confer OS advantage over monotherapies in patients with progressive GBM. The encouraging results of the addition of CCNU to BEV warrant investigation in further randomized trials.

Pivotal therapeutic trials for infiltrating gliomas and how they affect clinical practice

The therapeutic landscape of the management of low- and high-grade infiltrating gliomas continues to evolve. Daily clinical decision making in neuro-oncology clinics across the US is frequently challenging, especially for anaplastic and low grade primary brain tumors. The focus of this review is centered on treatments which are approved by the FDA and/or featured in the NCCN Guidelines. Systemic therapy trials using a variety of agents such as temozolomide, bevacizumab, and procarbazine, lomustine, vincristine (PCV), and lastly trials of local therapies including surgical trials using carmustine impregnated wafers as well as trials investigating the administration of tumor treating fields are evaluated. Pivotal trials on the treatment of the primary brain tumors are discussed in detail along with associated correlative studies.

Management of glioblastoma in elderly patients

Glioblastoma (GBM) is the most common primary malignant brain tumor in adults over 55years of age. The median age of diagnosis for patients with GBM is 64years old, with the incidence of patients between 75 and 85 increasing. The optimal treatment paradigm for elderly GBM patients continues to evolve due to the higher frequency of age-related and/or medical co-morbidities. Geriatric GBM patients have historically been excluded from larger, controlled clinical trials due to their presumed decreased likelihood of a sustained treatment response and/or a prolonged good outcome. Here, we highlight current treatment considerations of elderly GBM patients with respect to surgical, radiotherapeutic and systemic modalities, with considerations for improving future clinical outcomes for this patient population.

Clinical outcomes in recurrent glioblastoma with bevacizumab therapy: An analysis of the literature

Bevacizumab (BEV) is a common treatment for recurrent glioblastoma (GBM). After progression on BEV, there is no consensus on subsequent therapy, as multiple chemotherapy trials have failed to demonstrate discernible activity for salvage. A previous review (995 patients) estimated a progression free survival (PFS) on BEV of 4.2months (SD±2.1) with an overall survival (OS) after progression on BEV at 3.8months (SD±1). We endeavored to establish a more rigorous historical control, both as a benchmark for efficacy, and a prognostic tool for clinical practice. A comprehensive literature review was performed utilizing PubMed and societal presentation abstracts. A total 2388 patients from 53 arms of 42 studies were analyzed in three groups: 1) thirty-two studies in which survival post-BEV was determined by subtracting PFS from OS (2045 patients): PFS on BEV=4.38months (95% CI 4.09-4.68); OS post-BEV=3.36months (95% CI 3.12-3.66); 2) two studies (94 patients) in which OS post-BEV is reported: OS=3.26 (95% CI 2.39-4.42); 3) eight studies of salvage therapy after progression on BEV (249 patients): of OS post-BEV=4.46months (95% CI 3.68-5.54). These estimates provide a firm historical control for PFS on BEV, as well as OS after disease progression on BEV therapy.

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.

Outcomes and prognoses of patients with ovarian cancer using bevacizumab: 6-year experience in a tertiary care hospital of northern Taiwan

Purpose

Bevacizumab (BEV) has been used for ovarian cancer (OC) for years in Taiwan, but the associated data related to outcome is scant. This retrospective study reviewed patients with OC treated with BEV and analyzed their results.

Patients and methods

All patients with OC treated with BEV from 2009 to 2015 in the Linkou branch of Chang Gung Memorial Hospital in Northern Taiwan were included. According to the means of administration, the patients were classified into 6 groups as follows: A—BEV plus chemotherapy (C/T) for initial platinum-resistant (PR) recurrent OC, B—BEV plus C/T for initial platinum-sensitive (PS) recurrent OC, C—BEV alone for recurrent OC, D—BEV plus 1^st adjuvant C/T, E—BEV plus neoadjuvant C/T, and F—intraperitoneal (IP) BEV. Progression-free survival (PFS), overall survival (OS), hazard ratios (HRs), overall response rate (ORR), and mean number of BEV cycles were analyzed for groups A to E. Clinical improvement of ascites was assessed for group F.

Results

A comparison of early use (only one round of prior C/T) versus late use (multiple rounds of prior C/T) in patients of groups A and B showed a superior PFS (8.27 vs. 3.67, p = 0.037) in the early use group. No significant differences were found between groups A and B (PFS: 4.24 vs. 4.17 months, p = 0.690; OS: 10.06 vs. 9.93 months, p = 0.819; mean BEV cycles: 4.63 vs. 5.0 p = 0.992; ORR: 48.1% vs. 53.5%, p = 0.425). Comparing the response and non-response subgroups of patients in groups A and B, a better outcome was associated with endometrioid type cell (HR = 0.28, p = 0.008), good ECOG performance status (HR = 0.51, p = 0.005), and lack of ascites (HR = 0.67, p = 0.004). Comparing group C with groups A plus B, the BEV alone group had a poorer PFS (1.02 VS. 4.19, p = 0.04) and OS (1.42 VS. 9.99 p = 0.001) than the BEV plus C/T group. In group F, a good clinical benefit rate (85.6%) of ascites improvement was noted. Two patients had grade 5 gastrointestinal bleeding and venous/arterial thromboembolic events after administration of BEV. Grade 3 neutropenia and thrombocytopenia occurred more frequently in our study.

Conclusion

Early use of BEV combined with chemotherapy had a significant benefit in PFS for patients with recurrent OC. BEV plus chemotherapy was better than BEV alone for recurrent OC. In addition, IP BEV was helpful for improving clinical ascites.

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Zusammenfassung. Das Glioblastom rezidiviert regelmässig trotz multimodaler Erstlinientherapie innerhalb weniger Monate nach der Diagnose. Für diese Situation ist bislang noch kein Therapiestandard etabliert. Bevacizumab, ein Antikörper gegen den vaskulären endothelialen Wachstumsfaktor, weckte grosse Hoffnungen in der Therapie des Glioblastoms. Zwei Phase-III-Studien zeigten allerdings nur eine Verzögerung der Krankheitsprogression, nicht aber des Gesamtüberlebens, durch die Kombination der Standarderstlinientherapie mit Bevcizumab. Gleiches ergab die EORTC 26101-Rezidivtherapiestudie mit einer Kombination von Lomustin/Bevacizumab gegenüber einer Lomustin-Monotherapie. Zudem existieren widersprüchliche Beobachtungen zur Lebensqualität und Neurokognition. Trotz der insgesamt enttäuschenden Studienlage wird Bevacizumab aufgrund seines sehr guten palliativen Effektes von den Schweizer neuro-onkologischen Zentren als zugelassene Therapieoption in der Rezidivtherapie häufig eingesetzt. Vakzinierungs- und Immuntherapien eröffnen neue Einsatzmöglichkeiten für Bevacizumab in der Behandlung primärer Hirntumoren.

Efficacy of bevacizumab therapy in recurrent malignant gliomas in relation to the prior recurrence pattern or tumor location

Although promising preliminary results have been widely observed with bevacizumab for recurrent malignant gliomas, many unanswered questions remain to be resolved to achieve an optimal outcome. No predictive biomarkers of a survival benefit from bevacizumab have been established, and no consensus exists about the response or survival benefit regarding the prior recurrence pattern or tumor location. Here we retrospectively analyzed the clinical benefit from bevacizumab for recurrent malignant gliomas in relation to the prior recurrence pattern or tumor location. Thirty-one consecutive patients with recurrent malignant gliomas who were treated with bevacizumab were investigated. The treatment response and survival benefit from bevacizumab were analyzed in association with age, sex, Karnofsky performance status, prior pathological diagnosis, prior recurrence pattern, primary location of tumor, recurrence status, and expression of angiogenic and hypoxic markers. The group with leptomeningeal dissemination had a significantly shorter median overall survival with bevacizumab (OS_Bev) (6.0months, 95% confidence interval (CI) 1.4-10.7) compared to those in the local/distant group (11.8months, 95% CI 6.1-17.4). The median OS_Bev of the infratentorial tumor group and supratentorial tumor group were 9.2months (95% CI 5.0-13.4) and 10.4months (95% CI 6.6-14.3), respectively. With multivariate analysis, the prior recurrence pattern was the only independent prognostic factor of OS_Bev. Patients with leptomeningeal dissemination of recurrent malignant glioma experienced minimal benefit from bevacizumab. Therefore, in the context of cost effectiveness, bevacizumab is not recommended for patients with leptomeningeal dissemination.

Prolonged survival after bevacizumab rechallenge in glioblastoma patients with previous response to bevacizumab†

Background

The use of bevacizumab for recurrent glioblastoma is controversial. Here we show data on patients who responded to bevacizumab, then stopped bevacizumab for any reason other than progression and were rechallenged with bevacizumab at the time of subsequent progression.

Methods

This retrospective study included 28 patients, classified in 2 cohorts: those for whom the first exposure to bevacizumab (BEV-1) was first-line treatment for newly diagnosed glioblastoma (Bev-F; N = 12) and those for whom BEV-1 was second- or third-line treatment for recurrent disease after standard treatment (Bev-S; N = 16).

Results

All patients received standard radiotherapy plus temozolomide. Bev-F patients also received concomitant bevacizumab. All 28 patients received a total of 57 treatment lines with bevacizumab (12 first-line and 45 second- or further-line). Twenty-nine lines were rechallenges (BEV-2 [N = 26] or BEV-3 [N = 3]). Objective response to rechallenge was 58.6% and clinical benefit was 89.6%. Overall survival (OS) was 55 months for RPA class IV and 26.7 months for RPA class V patients (P = .01). OS was 26.7 months for Bev-F patients and 52.1 months for Bev-S patients (P = .004). Post-progression survival was 20 months for Bev-F patients and 39.6 months for Bev-S patients (HR = 0.26; P = .007).

Conclusion

This is the largest study to examine the impact of a bevacizumab rechallenge in glioblastoma patients who had responded to previous bevacizumab treatment but who stopped before progression. Our findings indicate that these patients can attain a second response or clinical benefit from re-introduction of bevacizumab. The potential benefit from intermittent versus continuous treatment warrants comparison in clinical trials.

Management of glioblastoma after recurrence: A changing paradigm

Glioblastoma remains the most common primary brain tumor after the age of 40years. Maximal safe surgery followed by adjuvant chemoradiotherapy has remained the standard treatment for glioblastoma (GBM). But recurrence is an inevitable event in the natural history of GBM with most patients experiencing it after 6-9months of primary treatment. Recurrent GBM poses great challenge to manage with no well-defined management protocols. The challenge starts from differentiating radiation necrosis from true local progression. A fine balance needs to be maintained on improving survival and assuring a better quality of life. Treatment options are limited and ranges from re-excision, re-irradiation, systemic chemotherapy or a combination of these. Re-excision and re-irradiation must be attempted in selected patients and has been shown to improve survival outcomes. To facilitate the management of GBM recurrences, a treatment algorithm is proposed.

The earlier the better? Bevacizumab in the treatment of recurrent MGMT-non-methylated glioblastoma

PURPOSE

The adequate second-line therapy of patients with glioblastoma (GBM) is a matter of ongoing debate. This particularly applies to patients with a non-methylated MGMT promotor who are known to have a poor response to alkylating chemotherapy. In some countries, antiangiogenic therapy with BEV is applied as second-line therapy, and in others nitrosourea therapy is second-line choice. It is an open question whether the delay of BEV to third-line therapy has a negative impact on survival.

METHODS

A total of 61 adult patients (median age 56.9 years) with MGMT-non-methylated relapsed GBM treated with BEV (n = 45) or nitrosourea (n = 16) as second-line therapy were analyzed retrospectively and compared regarding progression-free survival (PFS) and overall survival (OS).

RESULTS

Patients treated with second-line BEV had longer median PFS (107 days, 95 % CI 80.7-133.2 days) than patients with second-line nitrosourea (52 days, 95 % CI 36.3-67.7 days, P = 0.011, logrank test). However, there was no significant difference in overall survival (BEV median 170 days, 95 % CI 87.2-252.8 days; nitrosourea median 256 days, 95 % CI 159.9-352.0 days, P = 0.468). PFS was similar after BEV third-line therapy (median 117 days, 95 % CI 23.6-210.4 days) as compared to second-line BEV therapy (median 107 days, 95 % CI 80.7-133.3 days, P = 0.584).

CONCLUSION

Our findings suggest that early treatment with BEV in patients with MGMT-non-methylated relapsed GBM is associated with a better PFS, but not with superior OS, possibly implicating that the early, i.e., second-line, use of BEV is not mandatory and BEV treatment may safely be delayed to third-line therapy in this subgroup of patients.

Prognostic factors in recurrent glioblastoma patients treated with bevacizumab

The value of bevacizumab (BEV) in recurrent glioblastoma is unclear. Imaging parameters and progression-free survival (PFS) are problematic endpoints. Few data exist on clinical factors influencing overall survival (OS) in unselected patients with recurrent glioblastoma exposed to BEV. We retrospectively analyzed 174 patients with recurrent glioblastoma treated with BEV at two German brain tumor centers. We evaluated general patient characteristics, MGMT status, pretreatment, concomitant oncologic treatment and overall survival. Karnofsky performance score, number of prior chemotherapies, number of prior recurrences and combined treatment with irinotecan (IRI) were significantly associated with OS in univariate analysis. We did not find differences in OS related to sex, age, histology, MGMT status, prior surgical treatment or number of prior radiotherapies. Combined treatment with IRI and higher KPS both remained significantly associated with prolonged survival in multivariate analysis, but patients receiving IRI co-treatment had less advanced disease. Grouping into clinically relevant categories revealed an OS of 16.9 months from start of BEV in patients with first recurrence and KPS ≥ 80 % (n = 25). In contrast, in patients with second recurrence and KPS < 80 %, OS was 3.6 months (n = 27). Our observational data support an early use of BEV in patients with good performance status. The benefit of co-treatment with IRI in our cohort seems to be the result of biased patient recruitment.

Progression-free and overall survival in patients with recurrent Glioblastoma multiforme treated with last-line bevacizumab versus bevacizumab/lomustine

Bevacizumab (BEV) is widely used for treatment of patients with recurrent glioblastoma multiforme (GBM). 1-(2-Chlorethyl)-cyclohexyl-nitrosourea (CCNU, lomustine) monotherapy is an approved chemotherapeutical option for recurrent GBM. Recent evidence demonstrated a survival benefit of combined treatment with BEV and CCNU in patients with a first recurrence of GBM. We examined the outcome of recurrent GBM patients with BEV monotherapy versus BEV/CCNU therapy when used as last-line therapy. 35 patients with recurrent GBM treated between 2010 and 2014 were included in this retrospective study. Progression-free and overall survival was determined with reference to the beginning of BEV or BEV/CCNU therapy and initial diagnosis. 17 patients received BEV monotherapy, 18 patients received combined BEV and CCNU therapy. The impact of parameters such as IDH mutation, MGMT promoter methylation, tumor localization, histology and the number of surgeries were included in a multivariate ANOVA analysis. Furthermore, Karnofsky performance score (KPS), neurological function and toxicity were assessed. BEV/CCNU treatment led to an extension of PFS (6.11 months; 95% CL 3.41-12.98 months; log-rank p = 0.00241) and OS (6.59 months; 95% CL 5.51-16.3 months; log-rank p = 0.0238) of 2 months compared to BEV monotherapy. This survival advantage was independent of histology, IDH mutation status or the number of previous surgeries. Neurological function, KPS and toxicity were not significantly different between both treatment groups. Last-line therapy with BEV/CCNU results in a longer PFS and OS compared to BEV monotherapy and is well-tolerated. These findings confirm the role of these agents in the treatment of recurrent GBM and are in line with other studies.

Bevacizumab in recurrent glioblastoma: open issues

Recurrent glioblastoma represents a challenge in neuro-oncology since the prognosis is poor and current therapeutic options are limited. Bevacizumab has demonstrated activity in this setting in various clinical trials and has been approved by US FDA for the treatment of recurrent glioblastoma. Nevertheless, many issues still exist. In this article, we summarized the principal subjects of controversies that surround bevacizumab and its use in the treatment of recurrent glioblastoma.

Economic Evaluation of Bevacizumab for the First-Line Treatment of Newly Diagnosed Glioblastoma Multiforme

Purpose

The Avastin in Glioblastoma trial has shown that patients newly diagnosed with glioblastoma multiforme (GBM) treated with bevacizumab plus radiotherapy and temozolomide versus radiotherapy and temozolomide alone showed improvement in progression-free survival, possibly leading to a new indication for first-line use of bevacizumab in GBM. The cost-utility of this new intervention remains unknown; therefore, we developed a Markov model estimating the incremental cost-utility ratio (ICUR) from a Canadian public payer perspective.

Methods

We incorporated trial data for state transitions and treatment effects from the Avastin in Glioblastoma trial, costs and resource use data from Canadian published studies and databases, and utility parameters from published literature. We addressed uncertainty through one-way deterministic and probabilistic sensitivity analyses, extended the model to lifetime horizon and by another arm to compare first-line versus second-line use of bevacizumab on progression, performed value of information analysis, and performed US costing sensitivity analysis.

Results

Adding bevacizumab to radiotherapy and temozolomide resulted in increases of 0.13 quality-adjusted life-years (QALYs) and $80,000 per patient over 2-year time horizon at the base case analysis. The ICUR was $607,966/QALY (95% CI, $305,000/QALY to $2,550,000/QALY), with 0% chance of being cost effective at the $100,000/QALY willingness-to-pay threshold and never going below $450,000/QALY in the one-way sensitivity analysis. The ICUR using the US costing data was $787,519/QALY. The lifetime ICUR was $439,764/QALY (95% CI, $235,000/QALY to $1,520,000/QALY), never going below $350,000/QALY in the sensitivity analysis. Second-line use of bevacizumab on progression is more effective and less expensive than its first-line use. Value of information analysis revealed that future research is unwarranted.

Conclusion

Bevacizumab has only limited effectiveness and is therefore not likely to be cost effective in treating adult patients with newly diagnosed GBM.

Retrospective analysis of safety and feasibility of a 3 days on/11 days off temozolomide dosing regimen in recurrent adult malignant gliomas

AIMS

We report the safety and feasibility of a 3 days on/11 days off temozolomide regimen for the treatment of recurrent malignant gliomas.

PATIENTS & METHODS

Fifteen adult patients were treated; 14 were treated with 300 mg/m(2) and one treated with 250 mg/m(2).

RESULTS

We reviewed the toxicity, progression-free survival (PFS), overall survival and objective response rate. Two patients (13%) experienced grade 3 nausea/vomiting and six patients (40%) experienced grade 3 lymphopenia. Dose reduction and treatment delay occurred in eight (53%) cases. One patient discontinued treatment due to uncontrolled nausea/vomiting. Median PFS for glioblastoma patients was 4.1 months and 6-month PFS was 25%. Twelve patients exhibited stable disease (86%), one patient (7%) had progressive disease and one patient (7%) showed a partial response.

CONCLUSION

The '3 on/11 off' temozolomide regimen for recurrent high-grade gliomas was tolerable and warrants further study in a larger, prospective study.

Bevacizumab in recurrent glioblastoma: five informative patient scenarios

Glioblastoma is the most common and malignant primary brain tumour in adults. Maximum feasible surgical resection, radiotherapy and temozolomide chemotherapy at initial diagnosis have improved prognosis but rapid recurrence is typical and survival remains brief. There is an urgent need for effective new treatments and approval of the antiangiogenic agent bevacizumab for recurrent glioblastoma by Health Canada in 2009 has been the most notable recent therapeutic advance for this disease. This review with illustrative case studies highlights how bevacizumab has been incorporated into the treatment of glioblastoma in Canada and describes the ongoing controversies surrounding its clinical application.

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.

Impact of bevacizumab administered dose on overall survival of patients with progressive glioblastoma

Bevacizumab (BEV, Avastin(®)) produces durable objective radiological responses of 20-26 %, median response durations of 16-18 weeks, and median overall survival (mOS) of 31-40 weeks. While the use of BEV is well-established, the lack of dose-response studies in glioblastoma (GBM) patients raises the question whether current dosing practice is optimal. As a result of differing approaches to BEV dosing that ranged from the FDA approved package insert dose of 10 mg/kg every 2 weeks to 7.5 mg/kg every 3-4 weeks, among physicians within Northern California Kaiser Permanente hospitals over 4+ years, we did an IRB-approved retrospective analysis of patients seen in Northern California Kaiser Permanente facilities and treated with BEV. Between September 1, 2008 and August 31, 2013, 181 patients received BEV for tumor progression/recurrence starting 2.6 weeks after completion of chemoradiation. The integrated BEV administered dose-week (AUCBEV) for all patients had a median AUCBEV of 3.6 mg·wk/kg). Maximum likelihood analysis found patients over 65 years did worse than younger patients (p = 0.004), women lived longer (p = 0.002), and patients treated below the AUCBEV did better than those treated above the median AUCBEV (p = 0.003). mOS for BEV starting 1 month after chemoradiation was 45 versus 68 weeks (p = 0.012) and BEV starting 3 months after chemoradiation was 40 versus 74 weeks (p = 0.0085). Dosing BEV at half the standard dose for progressive/recurrent GBM was at least equivalent to or, maybe better than standard dosing. Unexplained was the observation that females had longer OS with BEV than males.

Patient outcome in the Belgian medical need program on bevacizumab for recurrent glioblastoma

Bevacizumab (BEV) has demonstrated anti-tumor activity in patients with recurrent glioblastoma (rGB). Given the unmet need for active therapeutic options in rGB patients, a medical need program was initiated by the Belgian competent authorities. Between November 2010 and February 2013, a total of 313 patients with rGB initiated treatment with BEV administered at a dose of 10 mg/kg every 2 weeks. All patients had failed prior treatment with at least radiation therapy and temozolomide and the majority of patients (70 %) were treated with corticosteroids at baseline. Patients received a median of 6 BEV administrations (range 1-53). Overall, BEV was well tolerated. During BEV treatment the WHO-Performance Score (WHO-PS) improved in 59 patients (19 %) and stabilized for at least 6 weeks in an additional 139 (44 %) patients. Corticosteroid treatment could be stopped in 16 % or reduced in dose in 32 % of patients. The best objective tumor response rate using RANO criteria (investigator's assessment) was 3.5 % CR, 22 % PR, 38 % SD and 37 % PD. The median and 6-month PFS were 13 weeks (95 % CI 12.7-14) and 27.3 % (95 % CI 22.3-32.5), median and 6-month OS rates were 26 weeks (23-29) and 52 % (46.4-58.6), respectively. WHO-PS (0-1 vs. 2-3) and baseline steroid use were significantly correlated with PFS and OS. Our observations support the use of BEV as a monotherapy for patients with rGB who have no alternative treatment options. Optimal benefit from BEV treatment is likely to be obtained when treatment is initiated before the performance status deteriorates to two or less.

Dose-dense temozolomide: is it still promising?

Glioblastoma (GBM) has proven to be incurable despite recent progress on its standard of care using temozolomide (TMZ) as the main trunk of initial therapy for newly diagnosed GBM. One of the main reasons accounting for the dismal prognosis is attributed to lack of active therapeutic regimens at recurrence. Since TMZ is the most active cytotoxic agent against GBM, and the standard dosing of TMZ has shown favorable safety profile in clinical trials, re-challenge with TMZ in increased dose density schedules for recurrent tumors that have evaded from prior standard TMZ therapy appears to be a rational approach and has been intensively exploited. A number of phase II clinical trials using different alternating scheduling of dose-dense TMZ (ddTMZ) have shown superior efficacy over the standard TMZ or historical controls with other alkylating agents including nitrosoureas and procarbazine. One ddTMZ schedule, consisting of a 21-days on/7-days off regimen was applied to newly-diagnosed GBM as the adjuvant monotherapy after completion of combined radiation and TMZ and failed to demonstrate survival benefit in a large phase III trial (RTOG 0525). Thus its role in TMZ-pretreated, recurrent GBM should be carefully pursuit in randomized trials, e.g., planned JCOG 1308 trial comparing a 7-days on/7-days off ddTMZ regimen used upfront at the first relapse followed by bevacizumab on progression versus bevacizumab alone, investigating whether insertion of ddTMZ prior to bevacizumab could bestow better outcome in the recurrent setting. In this article, mode of action, past trials, and future directions of ddTMZ therapy are discussed.

Pharmacologic therapies for malignant glioma: a guide for clinicians

This review covers the medical options for malignant gliomas based on the results of recent clinical trials and updated information on molecular markers of prognostic and predictive value. In addition to alkylating agents, the antiangiogenic drug bevacizumab is increasingly used, particularly in cases of recurrence. Supportive care, including antiedema agents, antiepileptic drugs and anticoagulants, represent complementary treatment approaches of the utmost clinical importance.

Bevacizumab for glioblastoma: current indications, surgical implications, and future directions

Initial enthusiasm after promising Phase II trials for treating recurrent glioblastomas with the antiangiogenic drug bevacizumab—a neutralizing antibody targeting vascular endothelial growth factor—was tempered by recent Phase III trials showing no efficacy for treating newly diagnosed glioblastomas. As a result, there is uncertainty about the appropriate indications for the use of bevacizumab in glioblastoma treatment. There are also concerns about the effects of bevacizumab on wound healing that neurosurgeons must be aware of. In addition, biochemical evidence suggests a percentage of tumors treated with bevacizumab for an extended period of time will undergo transformation into a more biologically aggressive and invasive phenotype with a particularly poor prognosis. Despite these concerns, there remain numerous examples of radiological and clinical improvement after bevacizumab treatment, particularly in patients with recurrent glioblastoma with limited therapeutic options. In this paper, the authors review clinical results with bevacizumab for glioblastoma treatment to date, ongoing trials designed to address unanswered questions, current clinical indications based on existing data, neurosurgical implications of bevacizumab use in patients with glioblastoma, the current scientific understanding of the tumor response to short- and long-term bevacizumab treatment, and future studies that will need to be undertaken to enable this treatment to fulfill its therapeutic promise for glioblastoma.

Phase II trial of triple tyrosine kinase receptor inhibitor nintedanib in recurrent high-grade gliomas

Bevacizumab is FDA-approved for patients with recurrent GBM. However, the median duration of response is only 4 months. Potential mechanisms of resistance include upregulated FGF signaling and increased PDGF-mediated pericyte coverage. Nintedanib is an oral, small-molecule tyrosine kinase inhibitor of PDGFR α/β, FGFR 1-3, and VEGFR 1-3 that may overcome resistance to anti-VEGF therapy. This was a two-stage phase II trial in adults with first or second recurrence of GBM, stratified by prior bevacizumab therapy (ClinicalTrials.gov number NCT01380782; 1199.94). The primary endpoint was PFS6 in the bevacizumab-naive arm (Arm A) and PFS3 in the post-bevacizumab arm (Arm B). Up to 10 anaplastic glioma (AG) patients were accrued to each arm in exploratory cohorts. Twenty-two patients enrolled in Arm A and 14 in Arm B. Arm A included 12 GBMs (55 %), 13 patients with one prior regimen (59 %), and median age 54 years (range 28-75). Arm B included 10 GBMs (71 %), one patient with one prior regimen (7 %), and median age 52 years (range 32-70). Median KPS overall was 90 (range 60-100). There were no responses. In Arm A (GBM only), PFS6 was 0 %, median PFS 28 days (95 % CI 27-83), and median OS 6.9 months (3.7-8.1). In Arm B (GBM only), PFS3 was 0 %, median PFS 28 days (22-28), and median OS 2.6 months (1.0-6.9). Among AG patients in each arm, PFS6 was 0 %. Treatment was well tolerated. In conclusion, nintedanib is not active against recurrent high-grade glioma, regardless of prior bevacizumab therapy.

Survival outcome of early versus delayed bevacizumab treatment in patients with recurrent glioblastoma

Bevacizumab (BEV) is widely used for treatment of patients with recurrent glioblastoma. It is not known if there are differences in outcome between early versus delayed BEV treatment of recurrent glioblastoma. We examined the relationship between the time of starting BEV treatment and outcomes in patients with recurrent glioblastoma. In this retrospective chart review, we identified patients with recurrent glioblastoma diagnosed between 2005 and 2011 who were treated with BEV alone or BEV-containing regimens. Data was analyzed to determine overall survival (OS) from time of diagnosis and progression free survival (PFS) from time of starting BEV. A total of 298 patients were identified, 112 patients received early BEV, 133 patients received delayed BEV, and 53 patients were excluded because they either progressed within 3 months of radiation or received BEV at the time of diagnosis. There was no significant difference in PFS between patients that received early BEV and those that received delayed BEV (5.2 vs. 4.3 months, p = 0.2). Patients treated with delayed BEV had longer OS when compared to those treated with early BEV (25.9 vs. 20.8 months, p = 0.005). In patients with recurrent glioblastoma, there was no significant difference in PFS from the time of starting BEV between early and delayed BEV. Although patients treated with delayed BEV seemed to have longer OS, a conclusion regarding OS outcome requires further prospective trials. These results may indicate that delaying treatment with BEV is not detrimental for survival of patients with recurrent glioblastoma.