Safety and Efficacy Study in Recurrent or Progressive Grade III or IV IDH1 Mutated Glioma

Malignant glioma, particularly glioblastoma multiforme (GBM, WHO grade IV astrocytic glioma) accounts for over half of all gliomas, which in turn account for 80% of all malignant brain and CNS tumors. In European and North American countries, the incidence rate is approximately four to five new cases per 100,000 people per year.

Most patients with glioblastoma are faced with a dismal prognosis. Advances in neurosurgery, radiation, and chemotherapy during the past decade have provided only small improvements in clinical outcome, with a 5-year survival rate remaining at less than 10%.The first-line treatment of GBM is usually surgery, both to confirm the diagnosis and to remove as much of the tumor as possible. Concurrent temozolomide with radiotherapy followed by adjuvant systemic temozolomide has produced a median survival of 14.6 to 16.6 months, and this regimen is now the standard of care for GBM, as well as grade III anaplastic glioma.

Regardless of the treatment regimen, the aggressive infiltration of glioblastoma throughout the brain typically produces progressive disability, ultimately leading to death in nearly all cases. Innovative treatment is urgently needed.

Molecular profiling is being used to separate patients with GBM into prognostic groups. A mutation affecting codon 132 of the isocitrate dehydrogenase 1 (IDH1) gene was found to occur in up to 12% of glioblastomas. A review of sequencing studies on large glioma patient cohorts have found IDH1 mutations present in 6% (range 3-16%).

IDH1 mutation is considered a definitive diagnostic molecular marker of glioblastomas and is considered more reliable and objective than clinical criteria. Long term outcome for patients with high-grade glioma including glioblastoma directly correlates to IDH1 mutation status. IDH1 mutated tumors have been associated with an improved outcome comparable to IDH1 wild-type tumors. IDH1 mutation has remained an independent favorable prognostic marker even after adjustment for age, grade, MGMT status, genomic profile and treatment in multivariate analysis. Median OS for glioblastoma patients following first recurrence is 9.8 months for IDH1 wildtype tumors versus 19.32 months for IDH1 mutated cancers. No increase in PFS was found.

Anaplastic astrocytoma is a rare, malignant brain tumor that arises from a subtype of glial cells that make up the majority of cells in the central nervous system, called astrocytes. Approximately 70-80% of WHO Grades II and III astrocytoma possess IDH mutations. In general, those diagnosed with initial grade III astrocytomas have a higher survival rate than patients with grade IV astrocytomas (5-year survival rate, Grade III, 71 participants, 49.2 ± 6.6 months vs. Grade IV, 216 patients, 9.6 ± 4.4 months). Interestingly, the presence of IDH mutations predict a favorable disease outcome with prolonged median survival in grade IV astrocytoma (IDH wild type: 15 months; IDH mutant: 31 months) and grade III anaplastic astrocytoma (IDH wild type: 20 months; IDH mutant: 65 months).

The reported median overall survival (OS) for glioblastomas is 14-15 months. Patients with initial diagnosis grade III astrocytoma have a considerably higher OS (45.2 ± 5.2 months with chemotherapy and radiotherapy, compared to 31.9 ± 2.7 months with no treatment), and progression free survival (PFS) (42.8 months treated with adjuvant temozolomide, compared to 19.0 months for people not treated with adjuvant temozolomide).

Patients with recurrent Grade III astrocytoma have effectively the same OS to grade IV tumors. A study carried out in 2018 showed 23 out of 100 patients experienced reoccurrence within an average time of 37 months after initial treatment and had an average OS after recurrence of 12.7 months. Additional research confirmed both that a high percentage of anaplastic astrocytomas reoccur and those that do occur have a median OS of approximately 10 months. Finally, 357 patients with highly anaplastic tumours were investigated between 1977 and 1989 (prior to the change in classification of brain tumors by the WHO). A total of 81 of these patients experienced tumour reoccurrence and required secondary treatment. The median OS for these patients was 53 weeks (13.2) months from the start of the secondary treatment. Based upon these studies, it is believed patients with IDH1 mutated recurrent or progressive Grade IV glioblastoma and IDH1 mutated recurrent or progressive Grade III astrocytoma have the same clinical prognosis with respect to progression free survival and overall survival and suitable for study in this protocol.

One reason for the poor prognosis of malignant glioma and astrocytoma patients is the difficulty of penetrating the blood brain barrier (BBB) with chemotherapy agents. Nasal brain delivery of chemotherapy offers a novel, paradigm shifting platform based on technology to deliver chemotherapy via inhalation to the brain tumor. The presumed mechanism of nasal brain delivery from preclinical rodent studies is thought to be via the olfactory and trigeminal nerves. Effective nasal brain delivery has been demonstrated in humans in other diseases. For example, Reger et al. have reported effective delivery of intranasal insulin for Alzheimer's disease.

NEO100 has been demonstrated to open the BBB in a reversible and nontoxic fashion in vitro and in vivo, enabling greatly increased brain entry of all tested therapeutics and was well tolerated in animals. Mechanistic studies revealed effects of NEO100 on different BBB transport pathways. An in vitro BBB, consisting of human astrocytes and brain endothelial cells, has been used to determine trastuzumab penetration when administered with NEO100, greatly increasing trastuzumab penetration. In vivo, IA NEO100-mediated BBB opening resulted in tumor-selective accumulation of trastuzumab , without detectable presence in normal brain tissue, along with increased presence of immune cell populations. IV delivery of trastuzumab or T-DM1 achieved significantly greater overall survival of tumor-bearing mice when combined with IA NEO100.

In a case lesson, after surgical removal of her recurrent GBM tumor, a patient received daily intranasal NEO100 therapy for more than 3 years before a second recurrence emerged. At that time, a final dose of NEO100 was given shortly before the tumor tissue was surgically removed, and the tissue was processed for high-performance liquid chromatography analysis of perillyl alcohol and its primary metabolite, perillic acid. Both molecules could readily be detected in the tumor tissue. This is the first demonstration of perillyl alcohol and perillic acid in brain tumor tissue from any patient. It reveals that intranasal administration of NEO100 is a valid approach to achieve delivery of this agent to a brain tumor. In view of the non-invasive and safe nature of this method, along with tentative indications of activity, these findings add confidence to the notion that intranasal administration of NEO100 holds potential as a new treatment option for brain-localized malignancies.

Perillyl alcohol, also called p-metha1,7-diene-6-ol,or 4-isopropenylcyclo-hexenecarbinol, is a monoterpene, isolated from the essential oils of lavender, peppermint, spearmint, and several other plants and synthesized by the mevalonate pathway. It has been previously demonstrated to have anti-cancer properties in preclinical studies in rodent models for a variety of cancers including mammary, pancreatic, and colon cancer. Although the exact mechanism of perillyl alcohol induced tumor regression is unknown, perillyl alcohol has been reported to modulate cellular processes that control cell growth and differentiation including G1 cell cycle arrest and induction of apoptosis.

Perillyl alcohol has also been shown to inhibit post-translational modification of proteins involved in signal transduction. It has been postulated that the anti-neoplastic activity of perillyl alcohol involves a decrease in the levels of isoprenylated Ras and Ras-related proteins, thereby reducing the physiological functioning of these proteins. Protein isoprenylation involves the post-translational modification of a protein by the covalent attachment of a lipophilic farnesyl isoprenoid group to a cysteine residue at or near the carboxyl terminus. Isoprenoid substrates for prenylprotein transferase enzymes include farnesyl pyrophosphate plus geranylgeranyl pyrophosphate, two intermediates in the mevalonate pathway. This action was attributed to the inhibition of farnesyl protein transferase activity. Farnesylation is the most critical part of the process that leads to the activation of Ras, and farnesyl transferase inhibitors exert their antitumor effect in part by inhibiting Ras-mediated signaling. A study revealed that H-Ras and K-Ras farnesylation were inhibited by perillyl alcohol.

Ras activity is elevated in malignant glioma tumors. Activated Ras stimulates other pathways essential for proliferation and progression through the cell cycle and inhibition of apoptosis in malignant gliomas. Moreover, the formation of malignant gliomas requires the cooperation of both Ras and Akt signaling. This cooperative effect has been demonstrated by somatic-cell gene transfer, during which transfer of either an activated form of K-Ras or Akt alone to neural progenitors was insufficient to form malignant glioma in vivo, but the combined effect of both pathways could initiate gliomagenesis. Thus, based on this known alteration in signal transduction involving K-Ras in malignant glioma, and its ability to induce cell cycle arrest and apoptosis, perillyl alcohol (NEO100) may be an attractive agent and warrants further clinical development.

Furthermore, intranasal delivery of NEO100 has the additional, potential benefit of direct drug delivery into the brain and avoiding systemic toxicity and first pass metabolism. It is believed the mechanism of action of NEO100 is similar in both patients with progressive or recurrent Grade IV gliomas who have IDH1 mutations and patients with progressive or recurrent Grade III astrocytomas who have IDH1 mutations making inclusion of both populations appropriate for this study.