Myeloid biomarkers associated with glioblastoma response to anti-VEGF therapy with aflibercept.

PURPOSE: VEGF and infiltrating myeloid cells are known regulators of tumor angiogenesis and vascular permeability in glioblastoma. We investigated potential blood-based markers associated with radiographic changes to aflibercept, which binds VEGF and placental growth factor (PlGF) in patients with recurrent glioblastoma. EXPERIMENTAL DESIGN: In this single-arm phase II trial, aflibercept was given intravenously every two weeks until disease progression. Plasma and peripheral blood mononuclear cells were collected at baseline and 24 hours, 14 days, and 28 days posttreatment. Plasma cytokines and angiogenic factors were quantified by using ELISA and multiplex bead assays, and myeloid cells were assessed by flow cytometry in a subset of patients. RESULTS: Circulating levels of VEGF significantly decreased 24 hours after treatment with aflibercept, coincident with radiographic response observed by MRI. PlGF initially decreased 24 hours posttreatment but increased significantly by days 14 and 28. Lower baseline levels of PlGF, elevated baseline levels of CTACK/CCL27, MCP3/CCL7, MIF, and IP-10/CXCL10, and a decrease in VEGFR1(+) monocytes from baseline to 24 hours were all associated with improved response. Tumor progression was associated with increases in circulating matrix metalloproteinase 9. CONCLUSIONS: These data suggest that decreases in VEGF posttreatment are associated with radiographic response to aflibercept. Elevated baseline chemokines of monocyte lineage in responding patients supports a role for myeloid cells and chemokines as potential biomarkers and regulators of glioma angiogenesis.

Phase II study of carboplatin and erlotinib (Tarceva, OSI-774) in patients with recurrent glioblastoma.

Targeting the epidermal growth factor receptor (EGFR) may be effective in a subset of glioblastoma patients. This phase II study assessed the clinical activity of erlotinib plus carboplatin and to determine molecular predictors of response. The primary endpoint was progression free survival (PFS). Patients with recurrent glioblastoma with no more than two prior relapses received carboplatin intravenously on day 1 of every 28-day cycle (target AUC of 6 mg x ml/min). Daily erlotinib at 150 mg/day was dose escalated to 200 mg/day, as tolerated. Clinical and MRI assessments were made every 4 and 8 weeks, respectively. Tumor tissue was evaluated for EGFR, AKT and phosphatase and tensin homolog (PTEN) status. One partial response (PR) was observed out of 43 assessable patients. Twenty patients (47%) had stable disease (SD) for an average of 12 weeks. Median PFS was 9 weeks. The 6-month PFS rate was 14%. Median overall survival (OS) was 30 weeks. This regimen was well tolerated with grade 3/4 toxicities of fatigue, leukopenia, thrombocytopenia and rash requiring dose reductions. A recursive partitioning analysis (RPA) predicted that patients with KPS >or=90 treated with more than 1 prior regimen had the highest OS. No correlation was observed between EGFR, Akt or PTEN expression and either PFS or OS. Carboplatin plus erlotinib is well tolerated but has modest activity in unselected patients. Future trials should be stratified based on optimal molecular or clinical characteristics.

Phase-1 trial of gefitinib and temozolomide in patients with malignant glioma: a North American brain tumor consortium study.

PURPOSE: This is a phase-I study of gefitinib in combination with temozolomide in patients with gliomas. The goal of the study was to define the maximum tolerated dose (MTD) and to characterize the pharmacokinetics of gefitinib when combined with temozolomide. PATIENTS AND METHODS: Patients were stratified according to co-administration of enzyme-inducing anti-epileptic drugs (EIAEDs). There were 26 evaluable patients enrolled (16 on EIAEDs, 10 not on EIAEDs). All but seven patients had Glioblastoma Multiforme (GBM), and only six cases had a Karnosfsky Performance Status (KPS) of less than 80; median age was 51 years. All had received prior radiotherapy and 14 patients had no prior chemotherapy. The starting dose of temozolomide was 150 mg/m(2)/day for 5 days every 28 days and could be escalated to a maximum dose of 200 mg/m(2)/day in subsequent cycles. The starting dose of gefitinib was 500 mg/day given by mouth on a continuous basis. Dose-limiting toxicity was assessed in cycle one only. RESULTS: For patients on EIAEDs, the MTD of gefitinib was 1,000 mg/day in combination with temozolomide. Dose-limiting toxicity (DLT) was due to diarrhea, nausea and vomiting. For patients not on EIAEDs, the MTD was 250 mg/day in combination with temozolomide. The DLT was due to increases in liver transaminases. Rash was not a significant toxicity at these dose levels. The peak concentration and AUC(0-24hr) at the 500 mg dose level was 1.8 and 2.5-fold lower, respectively, in the EIAED group compared to the non-EIAED group; trough levels of gefitinib increased in both groups consistent with the reported terminal half-life ranging from 27 to 51 h. CONCLUSION: The recommended phase-2 dose of gefitinib when used in combination with temozolomide is 1,000 and 250 mg/day, respectively, for patients on or not on EIAEDs.

Combination of the oncolytic adenovirus ICOVIR-5 with chemotherapy provides enhanced anti-glioma effect in vivo.

Novel therapies are clearly needed for gliomas, and the combination of oncolytic vectors with chemotherapy possesses a significant hope for the treatment of this malignancy. In addition, combination with chemotherapy allows for lower virus doses to achieve anticancer effect, thus resulting in lower undesirable toxicities due to viral proteins. In this work, we sought to determine whether combination of an oncolytic adenovirus ICOVIR-5, with RAD001 or temozolomide (TMZ) could result in enhanced anti-glioma effect in vivo. We assessed the in vitro cytotoxic effect and replication properties of ICOVIR-5 in combination with RAD001 or TMZ in U87 MG glioma cell line by MTT and TCID(50), respectively. Our data showed that in vitro treatment with RAD001 or TMZ not only interfered with adenovirus replication but, in addition, enhanced its oncolytic properties. To evaluate the in vivo anticancer effect, athymic mice bearing glioma xenografts (5 x 10(5) U87 MG cells/animal) received a single intratumoral injection of ICOVIR-5 (10(7) PFU/animal). RAD001 was given as a regimen of 5 mg/kg 5 days per week until the end of the experiment and TMZ was administered for 5 days at 7.5 mg/kg/mice. Of significance, combination of ICOVIR-5 with RAD001 or TMZ showed a potent anti-glioma effect in vivo, resulting in a dramatic extension of the median animal survival and in 20-40% animals becoming free of disease beyond 90 days.

A phase 2 trial of irinotecan (CPT-11) in patients with recurrent malignant glioma: a North American Brain Tumor Consortium study.

The purpose of this study was to determine the response to CPT-11 administered every three weeks to adults with progressive malignant glioma, treated with or without enzyme-inducing antiepileptic drug (EIAED) therapy, at the recommended phase 2 dose determined from a previous phase 1 study. Adult patients age 18 or older with a KPS of 60 or higher who had measurable recurrent grade III anaplastic glioma (AG) or grade IV glioblastoma multiforme (GBM) were eligible. No more than one prior chemotherapy was allowed, either as adjuvant therapy or for recurrent disease. The CPT-11 dose was 350 mg/m(2) i.v. every three weeks in patients not on EIAED and 750 mg/m(2) in patients on EIAED therapy. Patients with stable or responding disease could be treated until tumor progression or a total of 12 months of therapy. The primary end point of the study was to determine whether CPT-11 could significantly delay tumor progression, using the rate of six-month progression-free survival (PFS-6). The trial was sized to be able to discriminate between a 15% and 35% rate for the GBM group alone and between a 20% and 40% rate for the entire cohort. There were 51 eligible patients, including 38 GBM and 13 AG patients, enrolled. The median age was 52 and 42 years, respectively. PFS-6 for the entire cohort was 17.6%. PFS-6 was 15.7% (95% confidence interval [CI], 0.07-0.31) for the GBM patients and 23% (95% CI, 0.07-0.52) for AG patients. Toxicity for the group included diarrhea and myelosuppression. We conclude that the recommended phase 2 dose of CPT-11 for patients with or without EIAED was ineffective on this schedule, in this patient population.

Combination chemotherapy with 13-cis-retinoic acid and celecoxib in the treatment of glioblastoma multiforme.

In a phase II clinical trial, we sought to determine if combining celecoxib with 13-cis-retinoic acid (13-cRA, Accutane) was efficacious in the treatment of recurrent (progressive) glioblastoma multiforme (GBM). In parallel, we also sought to determine to what extent the outcomes from this clinical trial correlated with the findings from studies utilizing two murine intracerebral GBM models, U87MG and U251HF, to determine the predictive value of these murine models. In the clinical trial, 25 patients were studied at recurrence. Stable disease, which occurred in 44% of the patients, was the best response. The median progression-free survival (PFS) was 8 weeks, with a PFS at 6 months of only 19%. For the patients with stable disease, the median PFS was 24 weeks. The toxicity profile was unremarkable. The modest effect on PFS seen in this study agreed with the recent findings of another study, which showed a 19% PFS at 6 months in patients treated with 13-cRA alone. Thus, the combination of 13-cRA with celecoxib is not more effective than 13-cRA in the treatment of progressive GBM. In the murine model study, we found that long-term dosing with 13-cRA or celecoxib alone or in combination did not increase survival in animals with U87MG tumors but modestly increased survival in animals with U251HF tumors. There was no evidence of synergism between the two drugs. From this, we concluded that the animal studies generally predicted that the two agents would have only a modest effect alone and no additive effect when given in combination to patients.

Phase 1 trial of irinotecan (CPT-11) in patients with recurrent malignant glioma: a North American Brain Tumor Consortium study.

This study was conducted to determine the maximum tolerated dose and dose-limiting toxicity of irinotecan (CPT-11) administered every 3 weeks to adults with progressive malignant glioma who were treated with enzyme inducing antiepileptic drug (EIAED) therapy, and to compare the pharmacokinetics with those in patients not on EIAED therapy treated at the recommended phase 2 dose for other cancers. The CPT-11 dose was 350 mg/m(2) i.v. every 3 weeks and remained fixed in patients not on EIAED therapy, but the dose was escalated by 50-mg/m(2) increments in patients on EIAED therapy. CPT-11 and its metabolites SN-38, SN-38 glucuronide (SN-38G), and APC (7-ethyl-10[4-N-(5 aminopentanoic acid)-1-piperidine]-carbonyloxycamptothecin) were characterized in both groups. Patients on EIAEDs received 350 to 800 mg/m(2) of CPT-11. Dose-limiting toxicity was due to grade 3 diarrhea despite maximal doses of loperamide. The systemic levels of CPT-11, APC, SN-38G, and SN-38 were all lower in the EIAED group. There was a moderate-to-fair relationship between CPT-11 dose and the area under the curve (AUC) for CPT-11 and APC over the 2, but no relationship dosage range of 350 to 800 mg/m between CPT-11 dose and the AUC for SN-38 or SN-38G. At the 750-mg/m(2) dose, the AUC for CPT-11 (21.6 microg x h/ml) matched the AUC (21.6 microg x h/ml) in the non-EIAED group treated with 350 mg/m(2) of CPT-11. We conclude that the recommended phase 2 dose of CPT-11 for patients on EIAEDs is 750 mg/m(2) when given every 3 weeks. A phase 2 study of patients with recurrent malignant glioma is ongoing to assess the efficacy of CPT-11 when the dose is stratified according to the use of EIAEDs.

Phase II study of accelerated fractionation radiation therapy with carboplatin followed by PCV chemotherapy for the treatment of anaplastic gliomas.

PURPOSE: To conduct a Phase II one-arm study to evaluate the long-term efficacy and safety of accelerated fractionated radiotherapy combined with i.v. carboplatin for patients with previously untreated anaplastic gliomas. METHODS AND MATERIALS: Between 1988 and 1992, 90 patients received 1.9-2.0-Gy radiation 3 times a day with 2-h infusions of 33 g/m(2) carboplatin for two 5-day cycles separated by 2 weeks. After radiotherapy, patients received procarbazine, lomustine (CCNU), and vincristine (PCV) for 1 year or until the tumor progressed. RESULTS: Ninety patients were evaluable for analysis. Histologically, 69 had anaplastic astrocytoma; 14, anaplastic oligoastrocytoma; and 7, anaplastic oligodendroglioma. Gross total resection was performed in 20 (22%), subtotal resection in 45 (50%), and biopsy in 25 (28%); reoperation (total or subtotal resection) was performed in 50 (56%) patients. A multivariate analysis showed that a younger age (p = 0.026), Karnofsky performance score (KPS; p = 0.009), and brain necrosis (p = 0.0002) were predictive of a better survival. Results from analysis of extent of surgery (biopsy, subtotal resection, gross total resection) approached significance (p = 0.058). Radiation dose, irradiated tumor volume, and techniques used (boost and fields) were not significant variables. The median survival (MS) of all anaplastic glioma patients was 28.1 months; for anaplastic astrocytoma patients, MS was 28.7 months and 40.8 months for the combined anaplastic oligodendroglioma/oligoastrocytoma patients. Long-term survival occurred in 25% of anaplastic glioma patients who were alive 8.6 years after treatment was initiated. Treatment-induced necrosis was documented by surgery or autopsy in 19 (21%) patients; 21 (23%) had a mixed pattern of necrosis and tumor; and an additional 13 (14%) patients who did not have surgical or autopsy demonstration of predominant radiation necrosis had magnetic resonance imaging (MRI) evidence of radiation necrosis. Serious clinical neurologic deterioration and/or dementia requiring full-time caregiver attention were observed in 9 (10%) patients. CONCLUSION: When comparable selection criteria are applied, the rate of MS in this study is inferior to results attainable with current radiation and chemotherapy approaches, although the rates of long-term survival are comparable. Theoretically, patients failing therapy and dying earlier than anticipated may be because of excessive central nervous system (CNS) toxicity resulting from the combination of accelerated fractionated irradiation, intensive carboplatin chemotherapy before each radiation fraction, and postirradiation PCV chemotherapy. On the other hand, patients with treatment-induced necrosis survived significantly longer than patients who did not demonstrate MRI or histologic evidence of necrosis (MS, 106 months vs. 18-33 months).