RT-1 Treatment results of salvage gamma knife stereotactic radiosurgery and bevacizumab (AVAgamma therapy) for recurrent malignant glioma

Purpose: We report the treatment results of AVAgamma therapy combining gamma knife (GK) and bevacizumab for recurrent malignant glioma. Subjects: From August 2013 to January 2021, 71 patients (Grade 2:8 patients, Grade3:16 patients, Grade 4:47 patients) with recurrent malignant glioma treated with AVAgamma therapy as salvage therapy at the time of relapse after initial treatment. The average age is 55.7 years, with 44 men and 27 women. The tumor volume is 150 ml or less, and KPS is 40% or more as the indication of AVAgamma therapy. When the irradiation volume of the gamma knife was 15 ml or less, the marginal dose was 20 to 26 Gy, and when the irradiation volume was 15 ml or more, the marginal dose was 12 to 15 Gy in two divided doses.The mean therapeutic borderline dose was 24 Gy. Bevacizumab was administered 10 mg / kg or 15 mg / kg 1 to 10 times after GK. Methods: Median progression-free survival (mPFS) from AVAgamma treatment, median survival (mOS), and mOS from initial treatment were examined and compared with mOS in the RPA classification of recurrent glioma. Results: In relapsing glioma RPA classification, NABTT CNC class 2 mOS is 17.2 months, class 3 mOS is 3.8 months, class 5 mOS is 5.6 months, class 6 mOS is 6.4 months, but mOS from AVAgamma therapy is 18 months in class 3, 11 months in class 5, 9 months in class 6. The survival time has been extended in class3, class5, class6. Discussion: By AVAgamma therapy, it was thought that recurrent lesions were locally controlled and life prognosis was prolonged. Conclusion: AVAgamma therapy is thought to prolong the survival of recurrent malignant glioma and play an important role as salvage treatment.

Boron Neutron Capture Therapy and Add-on Bevacizumab in Patients with Recurrent Malignant Glioma

Introduction: Boron neutron capture therapy (BNCT) has shown excellent survival data but increases in radiation necrosis against recurrent malignant glioma (MG) in previous studies. We proposed that bevacizumab may reduce radiation injury from BNCT by re-irradiation. We evaluated the efficacy and safety of a combination therapy of BNCT and add-on bevacizumab in patients with recurrent MG.Methods: Patients with recurrent MG were treated with reactor-based BNCT. Treatment with bevacizumab (10 mg/kg) was initiated 1–4 weeks after BNCT irradiation and was re-administered every 2–3 weeks until disease progression. Initially diagnosed glioblastomas were categorized as primary glioblastoma (pGBM) and other forms of MG were categorized as non-pGBM. Results: Twenty-five patients (14 with pGBM and 11 with non-pGBM) were treated with BNCT and add-on bevacizumab. The 1-year survival rate for pGBM and non-pGBM was 63.5% (95% CI, 33.1–83.0) and 81.8% (95%CI, 44.7–95.1), respectively. The median OS was 21.4 months (95% CI, 7.0–36.7) and 73.6 months (95% CI, 11.4–77.2) for pGBM and non-pGBM, respectively (p = 0.0428). The median PFS was 8.3 months (95%CI, 4.2–12.1) and 15.6 months (95% CI, 3.1–29.8) for pGBM and non-pGBM, respectively (p = 0.0207). Alopecia occurred in all patients. Six patients experienced adverse events ≥ grade 3.Conclusions: BNCT and add-on bevacizumab were found to provide both a long OS and a long PFS, compared to the previous studies of BNCT alone for recurrent MG. The add-on bevacizumab may reduce the detrimental effects of BNCT radiation, including pseudoprogression and radiation necrosis.

Effect of temozolomide combined with radiotherapy on survival and MGMT protein expression in recurrent malignant glioma patients

Purpose: To investigate the effect of temozolomide (TMZ) combined with radiotherapy (RT) on O-6- methylguanine-DNA methyltransferase (MGMT) protein and survival of recurrent malignant glioma patients. Methods: Ninety-two patients with malignant glioma in our hospital from January 2014 to January 2015 were assigned to study and control groups using the random table method. Subjects in the control group received radiotherapy (total dose in the range of 60 – 75 Gy), while those in the study group were given TMZ orally (75 mg/m2) daily in addition to radiotherapy, as well as TMZ at 150 – 200 mg/m2. After treatment, clinical effectiveness was compared for the two groups. Changes in methylation of MGMT gene were determined in the two groups. The patients were followed up for 3 years, and the degrees of survival and recurrence were recorded. Results: Total effectiveness of clinical treatment was markedly higher in the study group (76.09 %) than in the control group (45.65 %; p < 0.05). One month after radiotherapy, significant decrease in MGMT gene methylation was seen in patients in the study group, relative to control patients (p < 0.05). Patients in the study group had lower median recurrence but higher degree of survival in the 2nd and 3rd years, relative to control patients (p < 0.05). Conclusion: The combination of temozolomide and radiotherapy is more effective than radiotherapy in the treatment of recurrent malignant glioma. The combined treatment significantly inhibits tumor recurrence in patients, and improves their prognosis and standard of life.

Study protocol of a Phase I/IIa clinical trial of Ad-SGE-REIC for treatment of recurrent malignant glioma

Malignant glioma is one of the most common brain cancers in humans, which is very devastating. The expression of reduced expression in immortalized cells/Dickkopf-3 (REIC/Dkk-3) is decreased in various human cancers. Lately, we have developed a novel second-generation adenoviral vector that expresses REIC/Dkk-3 (Ad-SGE-REIC) and revealed its antiglioma efficacy. The present investigator-initiated clinical trial is a single-arm, prospective, nonrandomized, noncomparative, open-label, single-center trial performed at Okayama University Hospital, Okayama, Japan. The primary end points are dose-limiting toxicities and the incidence of adverse events. The secondary end points are the objective response rate and immunological assessment. Use of Ad-SGE-REIC will help to improve the prognosis of patients with malignant brain tumors.

STMO-04 LOCAL CONVECTION-ENHANCED DELIVERY OF CHEMOTHERAPY AS TREATMENT FOR BRAIN TUMORS

BACKGROUND Convection-enhanced delivery (CED) of therapeutic agents is a promising local delivery technique that has been extensively studied as a treatment for CNS diseases over the last 2 decades. Applying this technique to treat brain tumors, we have been working to develop novel local chemotherapy against brain tumors. In the meanwhile, clinical trial against diffuse intrinsic brain tumor aiming at Japanese “shonin” approval is recruiting patients. In this study, potential of local CED based chemotherapy against supratentorial brain tumor is discussed. METHODS Until today, we have evaluated the safety and efficacy of local CED of nimustine hydrochloride against supratentorial malignant glioma patients in the three prospective, single institute, nonrandomized, open-label studies. Among those, one study recruited the recurrent malignant glioma patients whose enhanced tumor can be surgically resected. After the resection of the tumor, CED of ACNU was performed targeting the surrounding brain. Temozolomide was also given for 5 days during this trial. RESULTS Seven patients; 4 male and 3 female, age 33–71 y.o. (median 54 y.o.), were treated in this study. Five patients suffered glioblastoma and two suffered anaplastic astrocytoma. After the treatment, all seven patients lived longer than a year; one survived three years, one survived four and a half years, and one with glioblastoma is still alive after 5 years. DISCUSSION Potential efficacy of local chemotherapy delivering nimustine hydrochloride with CED against recurrent malignant glioma was suggested. Further study is required to pave the way for this strategy against supratentorial malignant gliomas.

ACT-15 AD-SGE-REIC GENE THERAPY FOR MALIGNANT GLIOMA

INTRODUCTION Malignant gliomas are one of the most common and aggressive intracranial neoplasms in humans. Expression of the gene encoding reduced expression in immortalized cells/Dickkopf-3 (REIC/Dkk-3) is reduced in a variety of human cancer cells. We previously showed the antitumor effect of an adenoviral vector carrying REIC/Dkk-3 gene (Ad-CAG-REIC). Recently, we have also developed a novel adenoviral vector expressing REIC/Dkk-3 (Ad-SGE-REIC). We assessed the anti-glioma effect of the Ad-SGE-REIC and planned a clinical trial of Ad-SGE-REIC for malignant glioma. MATERIALS AND METHODS We evaluated a cytotoxicity assay to treatments with Ad-SGE-REIC, Ad-CAG-REIC, or Ad-LacZ (control) using malignant glioma cells. The survival of mice in each group was analyzed by the Kaplan-Meier method. We also performed Good Laboratory Practice (GLP) toxicology tests and prepared a protocol for this clinical trial. RESULTS The treatment with Ad-SGE-REIC showed the number of malignant glioma cells attached to the bottom of culture wells was significantly reduced in a time-dependent manner. Mice treated with Ad-SGE-REIC significantly prolonged survival time more than those treated with other vectors. A cGMP product of Ad-SGE-REIC was developed and supplied by a startup biotech company, Momotaro-Gene Inc. We conducted GLP toxicology tests using the intracranial injection of higher doses of Ad-SGE-REIC at Shin Nippon Biomedical Laboratories (SNBL Japan). After finishing the consultation with Pharmaceuticals and Medical Devices Agency (PMDA), we prepared a protocol for a phase I/IIa clinical trial of Ad-SGE-REIC for the treatment of recurrent malignant glioma with our academic research organization (ARO), supported by Japan Agency for Medical Research and Development (AMED). This protocol was reviewed by our institution review board in March 2019. We submitted a notification of this trial in April 2019. CONCLUSIONS We demonstrated the anti-glioma effect of Ad-SGE-REIC. We start a phase I/IIa clinical trial of Ad-SGE-REIC for the treatment of recurrent malignant glioma (https://jrct.niph.go.jp/en-latest-detail/jRCT2063190013).

ATIM-21. THE CURRENT STATUS OF AD-SGE-REIC GENE THERAPY FOR MALIGNANT GLIOMA

INTRODUCTION Expression of the gene encoding reduced expression in immortalized cells/Dickkopf-3 (REIC/Dkk-3) was reported to be reduced in a variety of human cancer cells. We previously examined the antitumor effect of an adenoviral vector carrying REIC/Dkk-3 gene (Ad-CAG-REIC). Recently, a novel adenoviral vector expressing REIC/Dkk-3 has also been developed based on the cytomegalovirus promoter-driven super gene expression system (Ad-SGE-REIC). We evaluated the anti-glioma effect of the Ad-SGE-REIC and planned a clinical trial of Ad-SGE-REIC for malignant glioma. MATERIALS AND METHODS We evaluated a cytotoxicity assay to treatments with Ad-SGE-REIC, Ad-CAG-REIC, or Ad-LacZ (control) using malignant glioma cells. The survival of mice in each group was analyzed by the Kaplan–Meier method. We also performed Good Laboratory Practice (GLP) toxicology tests and prepared a protocol for this clinical trial. RESULTS In the cytotoxicity assay, after treatment with Ad-SGE-REIC, the number of malignant glioma cells attached to the bottom of culture wells was significantly reduced in a time-dependent manner. Mice treated with Ad-SGE-REIC survived significantly longer than those treated with other vectors. We also performed GLP toxicology tests using intracranial injection of higher doses of Ad-SGE-REIC in rats at Shin Nippon Biomedical Laboratories (SNBL Japan) to determine the injection dose of Ad-SGE-REIC for this clinical trial. After finishing the consultation with Pharmaceuticals and Medical Devices Agency (PMDA), we prepared a protocol for a phase I/IIa clinical trial of Ad-SGE-REIC for the treatment of recurrent malignant glioma supported by Japan Agency for Medical Research and Development (AMED). This protocol was reviewed by institution review board (IRB) in March 2019. We submitted a notification of this trial in April 2019. CONCLUSIONS We demonstrated the anti-glioma effect of Ad-SGE-REIC. We will start a phase I/IIa clinical trial of Ad-SGE-REIC for the treatment of recurrent malignant glioma.