Victor A. Levin

Outcomes and Prognostic Factors in Recurrent Glioma Patients Enrolled Onto Phase II Clinical Trials

PURPOSE To determine aggregate outcomes and prognostic covariates in patients with recurrent glioma enrolled onto phase II chemotherapy trials. PATIENTS AND METHODS Patients from eight consecutive phase II trials included 225 with recurrent glioblastoma multiforme (GBM) and 150 with recurrent anaplastic astrocytoma (AA). Their median age was 45 years (range, 15 to 82 years) and their median Karnofsky performance score was 80 (range, 60 to 100). Prognostic covariates were analyzed with respect to tumor response, progression-free survival (PFS), and overall survival (OS) by multivariate logistic and Cox proportional hazards regression analyses. RESULTS Overall, 34 (9%) had complete or partial response, whereas 80 (21%) were alive and progression-free at 6 months (APF6). The median PFS was 10 weeks and median OS was 30 weeks. Histology was a robust prognostic factor across all outcomes. GBM patients had significantly poorer outcomes than AA patients. The APF6 proportion was 15% for GBM and 31% for AA, whereas the median PFS was 9 weeks for GBM and 13 weeks for AA. Results were also significantly poorer for patients with more than two prior surgeries or chemotherapy regimens. CONCLUSION Histology is a dominant factor in determining outcome in patients with recurrent glioma enrolled onto phase II trials. Future trials should be designed with separate histology strata.

A mutant oncolytic adenovirus targeting the Rb pathway produces anti-glioma effect in vivo

Effective anti cancer strategies necessitate the use of agents that target tumor cells rather than normal tissues. In this study, we constructed a tumor-selective adenovirus, Δ24, that carries a 24-bp deletion in the E1A region responsible for binding Rb protein. Immunoprecipitation analyses verified that this deletion rendered Δ24 unable to bind the Rb protein. However, titration experiments in 293 cells demonstrated that the Δ24 adenovirus could replicate in and lyse cancer cells with great efficiency. Lysis of most human glioma cells was observed within 10–14 days after infection with Δ24 at 10 PFU/cell. In vivo, a single dose of the Δ24 virus induced a 66.3% inhibition (P<0.005) and multiple injections, an 83.8% inhibition (P<0.01) of tumor growth in nude mice. However, normal fibroblasts or cancer cells with restored Rb activity were resistant to the Δ24 adenovirus. These results suggest that the E1A-mutant Δ24 adenovirus may be clinically and therapeutically useful against gliomas and possibly other cancers with disrupted Rb pathway.

Phase II Trial of the Antiangiogenic Agent Thalidomide in Patients With Recurrent High-Grade Gliomas

PURPOSE Little progress has been made in the treatment of adult high-grade gliomas over the last two decades, thus necessitating a search for novel therapeutic strategies. Malignant gliomas are vascular or angiogenic tumors, which leads to the supposition that angiogenesis inhibition may represent a potentially promising strategy in the treatment of these tumors. We present the results of a phase II trial of thalidomide, a putative inhibitor of angiogenesis, in the treatment of adults with previously irradiated, recurrent high-grade gliomas. PATIENTS AND METHODS Patients with a histologic diagnosis of anaplastic mixed glioma, anaplastic astrocytoma, or glioblastoma multiforme who had radiographic demonstration of tumor progression after standard external-beam radiotherapy with or without chemotherapy were eligible. Patients were initially treated with thalidomide 800 mg/d with increases in dose by 200 mg/d every 2 weeks until a final daily dose of 1,200 mg was achieved. Patients were evaluated every 8 weeks for response by both clinical and radiographic criteria. RESULTS A total of 39 patients were accrued, with 36 patients being assessable for both toxicity and response. Thalidomide was well tolerated, with constipation and sedation being the major toxicities. One patient developed a grade 2 peripheral neuropathy after treatment with thalidomide for nearly a year. There were two objective radiographic partial responses (6%), two minor responses (6%), and 12 patients with stable disease (33%). Eight patients were alive more than 1 year after starting thalidomide, although almost all with tumor progression. Changes in serum levels of basic fibroblastic growth factor (bFGF) were correlated with time to tumor progression and overall survival. CONCLUSION Thalidomide is a generally well-tolerated drug that may have antitumor activity in a minority of patients with recurrent high-grade gliomas. Future studies will better define the usefulness of thalidomide in newly diagnosed patients with malignant gliomas and in combination with radiotherapy and chemotherapy. Additionally, studies will be needed to confirm the potential utility of changes in serum bFGF as a marker of antiangiogenic activity and/or glioma growth.

Superiority of post-radiotherapy adjuvant chemotherapy with CCNU, procarrazine, and vincristine (PCV) over BCNU for anaplastic gliomas: NCOG 6G61 final report

Data from Northern California Oncology Group protocol 6G61, which was closed in February 1983, were reanalyzed in December 1988. The protocol called for a randomized trial that compared the effects of following 60 Gy radiation/oral hydroxyurea treatment with either carmustine (BCNU) or the combination of procarbazine, lomustine (CCNU), and vincristine (PCV) for two histologic strata: glioblastoma multiforme and other anaplastic gliomas. PCV produced longer survival and time to tumor progression than BCNU for both histologic groups, although the difference was statistically significant only for the anaplastic gliomas. With PCV treatment, time to progression and survival doubled for anaplastic glioma patients in the 50th and 25th percentiles.

Phase I/II Study of Imatinib Mesylate for Recurrent Malignant Gliomas: North American Brain Tumor Consortium Study 99-08

Purpose: Phase I: To determine the maximum tolerated doses, toxicities, and pharmacokinetics of imatinib mesylate (Gleevec) in patients with malignant gliomas taking enzyme-inducing antiepileptic drugs (EIAED) or not taking EIAED. Phase II: To determine the therapeutic efficacy of imatinib. Experimental Design: Phase I component used an interpatient dose escalation scheme. End points of the phase II component were 6-month progression-free survival and response. Results: Fifty patients enrolled in the phase I component (27 EIAED and 23 non-EIAED). The maximum tolerated dose for non-EIAED patients was 800 mg/d. Dose-limiting toxicities were neutropenia, rash, and elevated alanine aminotransferase. EIAED patients received up to 1,200 mg/d imatinib without developing dose-limiting toxicity. Plasma exposure of imatinib was reduced by ∼68% in EIAED patients compared with non-EIAED patients. Fifty-five non-EIAED patients (34 glioblastoma multiforme and 21 anaplastic glioma) enrolled in the phase II component. Patients initially received 800 mg/d imatinib; 15 anaplastic glioma patients received 600 mg/d after hemorrhages were observed. There were 2 partial response and 6 stable disease among glioblastoma multiforme patients and 0 partial response and 5 stable disease among anaplastic glioma patients. Six-month progression-free survival was 3% for glioblastoma multiforme and 10% for anaplastic glioma patients. Five phase II patients developed intratumoral hemorrhages. Conclusions: Single-agent imatinib has minimal activity in malignant gliomas. CYP3A4 inducers, such as EIAEDs, substantially decreased plasma exposure of imatinib and should be avoided in patients receiving imatinib for chronic myelogenous leukemia and gastrointestinal stromal tumors. The evaluation of the activity of combination regimens incorporating imatinib is under way in phase II trials.

Randomized Double-Blind Placebo-Controlled Trial of Bevacizumab Therapy for Radiation Necrosis of the Central Nervous System

PURPOSE To conduct a controlled trial of bevacizumab for the treatment of symptomatic radiation necrosis of the brain. METHODS AND MATERIALS A total of 14 patients were entered into a placebo-controlled randomized double-blind study of bevacizumab for the treatment of central nervous system radiation necrosis. All patients were required to have radiographic or biopsy proof of central nervous system radiation necrosis and progressive neurologic symptoms or signs. Eligible patients had undergone irradiation for head-and-neck carcinoma, meningioma, or low- to mid-grade glioma. Patients were randomized to receive intravenous saline or bevacizumab at 3-week intervals. The magnetic resonance imaging findings 3 weeks after the second treatment and clinical signs and symptoms defined the response or progression. RESULTS The volumes of necrosis estimated on T(2)-weighted fluid-attenuated inversion recovery and T(1)-weighted gadolinium-enhanced magnetic resonance imaging scans demonstrated that although no patient receiving placebo responded (0 of 7), all bevacizumab-treated patients did so (5 of 5 randomized and 7 of 7 crossover) with decreases in T(2)-weighted fluid-attenuated inversion recovery and T(1)-weighted gadolinium-enhanced volumes and a decrease in endothelial transfer constant. All bevacizumab-treated patients-and none of the placebo-treated patients-showed improvement in neurologic symptoms or signs. At a median of 10 months after the last dose of bevacizumab in patients receiving all four study doses, only 2 patients had experienced a recurrence of magnetic resonance imaging changes consistent with progressive radiation necrosis; one patient received a single additional dose of bevacizumab and the other patient received two doses. CONCLUSION The Class I evidence of bevacizumab efficacy from the present study in the treatment of central nervous system radiation necrosis justifies consideration of this treatment option for people with radiation necrosis secondary to the treatment of head-and-neck cancer and brain cancer.

Clinical InvestigationRandomized Double-Blind Placebo-Controlled Trial of Bevacizumab Therapy for Radiation Necrosis of the Central Nervous System

PURPOSE To conduct a controlled trial of bevacizumab for the treatment of symptomatic radiation necrosis of the brain. METHODS AND MATERIALS A total of 14 patients were entered into a placebo-controlled randomized double-blind study of bevacizumab for the treatment of central nervous system radiation necrosis. All patients were required to have radiographic or biopsy proof of central nervous system radiation necrosis and progressive neurologic symptoms or signs. Eligible patients had undergone irradiation for head-and-neck carcinoma, meningioma, or low- to mid-grade glioma. Patients were randomized to receive intravenous saline or bevacizumab at 3-week intervals. The magnetic resonance imaging findings 3 weeks after the second treatment and clinical signs and symptoms defined the response or progression. RESULTS The volumes of necrosis estimated on T(2)-weighted fluid-attenuated inversion recovery and T(1)-weighted gadolinium-enhanced magnetic resonance imaging scans demonstrated that although no patient receiving placebo responded (0 of 7), all bevacizumab-treated patients did so (5 of 5 randomized and 7 of 7 crossover) with decreases in T(2)-weighted fluid-attenuated inversion recovery and T(1)-weighted gadolinium-enhanced volumes and a decrease in endothelial transfer constant. All bevacizumab-treated patients-and none of the placebo-treated patients-showed improvement in neurologic symptoms or signs. At a median of 10 months after the last dose of bevacizumab in patients receiving all four study doses, only 2 patients had experienced a recurrence of magnetic resonance imaging changes consistent with progressive radiation necrosis; one patient received a single additional dose of bevacizumab and the other patient received two doses. CONCLUSION The Class I evidence of bevacizumab efficacy from the present study in the treatment of central nervous system radiation necrosis justifies consideration of this treatment option for people with radiation necrosis secondary to the treatment of head-and-neck cancer and brain cancer.

Phase II Trial of Temozolomide Plus the Matrix Metalloproteinase Inhibitor, Marimastat, in Recurrent and Progressive Glioblastoma Multiforme

PURPOSE Novel therapies are needed for patients with recurrent glioblastoma multiforme (GBM). Because there is evidence that temozolomide (TMZ) has some activity in GBM and is well tolerated, and because of laboratory evidence that metalloproteinases are important in glioma cell invasion, the combination of TMZ and the matrix metalloproteinase inhibitor marimastat (MRM) in patients with recurrent GBM was studied. PATIENTS AND METHODS Forty-four patients with recurrent GBM after standard radiotherapy were enrolled. For 19 patients, this therapy was their first chemotherapy after tumor progression after irradiation; 25 others had received chemotherapy previously. TMZ 150 to 200 mg/m(2) days 1 to 5 and MRM 50 mg days 8 to 28 was administered at 28-day intervals for two cycles; then patients were reevaluated. Treatment continued until progression of tumor or toxicity developed. RESULTS Joint and tendon pain was the major therapy-related toxicity and was reported in 47% of patients. Five patients (11%) were removed from the study because of intolerable joint pain. For all patients, the progression-free survival (PFS) at 6 months was 39%. Median PFS was 17 weeks, median overall survival was 45 weeks, and 12-month PFS was 16%. CONCLUSION The combination of TMZ and MRM resulted in a PFS at 6 months that exceeded the literature target by 29%. This drug combination met phase II study criteria; further study in recurrent patients with GBM might be warranted. Further study of therapy-induced joint pain is necessary.

Cognitive Function as a Predictor of Survival in Patients With Recurrent Malignant Glioma

PURPOSE To determine the contribution of cognitive function in predicting the survival of patients with recurrent malignant brain tumors. PATIENTS AND METHODS A total of 80 patients with recurrent glioblastoma multiforme or anaplastic astrocytoma were seen for baseline evaluations before beginning a phase I or phase II clinical trial. Each patient received a battery of nine brief tests measuring cognitive function, ability to perform activities of daily living (ADLs), and quality of life (QOL). Tests were given monthly after treatment was begun. RESULTS Performance on a test of verbal memory was independently and strongly related to survival after accounting for age, Karnofsky performance status score, histology, and time since diagnosis. Models incorporating three of nine and all nine tests in the battery accounted for significantly more variance in survival than did the clinical variables alone. Measures of QOL and ADLs (bathing, feeding, and so on) were not independently related to survival, although they provide clinical information that is important for patient care. CONCLUSION These results indicate that a multifaceted assessment of cognition, QOL, and patient function is practical for brain tumor patients in clinical trials and can provide information regarding the relative risks versus benefits of new treatment regimens that supplements the information from the usual clinical variables.

Cerebrospinal Fluid Production by the Choroid Plexus and Brain

The production of cerebrospinal fluid and the transport of 24Na from the blood to the cerebrospinal fluid were studied simultaneously in normal and choroid plexectomized rhesus monkeys. Choroid plexectomy reduced the production of cerebrospinal fluid by an average of 33 to 40 percent and the rate of appearance of 24Na in the cerebrospinal fluid and its final concentration were proportionately reduced. In both normal and plexectomized animals, 24Na levels were found to be markedly greater in the gray matter surrounding the ventricles and in the gray matter bordering the subarachnoid space. That sodium exchanges in these two general areas of the brain may be linked to the formation of the cerebrospinal fluid is discussed here.