Exploratory Evaluation of AR-42 Histone Deacetylase Inhibitor in the Treatment of Vestibular Schwannoma and Meningioma

This will be a multi-center, proof of concept phase 0 study to assess the suppression of p-AKT in Vestibular Schwannoma (VS) and meningiomas by AR-42 in adult patients undergoing tumor resection. AR-42 is a small molecule which crosses the blood brain barrier (BBB) in rodents, but the investigators are not certain yet if it will penetrate human VS. Meningiomas are outside the BBB, but seem to be unusually resistant to all current medical treatments. The primary endpoint of the bioactivity of suppression of p-AKT by AR-42 was selected as drug activity seems more informative than bioavailability. Our preclinical data and others have shown dose dependent suppression of p-AKT by AR-42 in both VS and meningiomas.

This is a multi-center, proof of concept phase 0 study to assess the suppression of p-AKT in VS and meningiomas by AR-42 in adult patients undergoing NF2-tumor resection. AR-42 will be administered three times per week beginning 3 weeks prior to surgery. A total of ten doses, +/- 1 dose at 40 mg/dose, will be self-administered orally by study participants at approximately the same time every day (+/- 1 hour, preferably in the evening) 3 times per week for 3 weeks pre-operatively, with the last dose taken the night before surgery. Patients will be evaluated within the context of their standard post-operative follow up which includes within 2 days of surgery and again at 2 weeks (+/- 10 days) after surgery. Samples will be shipped to the participating laboratories (OSU Comprehensive Cancer Center (CCC) Pharmacoanalytical Shared Resource (PhASR) and Nationwide Children's Research Institute) for assessment of intratumoral drug concentration and assessment of intratumoral disease markers. During surgery, four blood samples will also be obtained and sent to the cooperating laboratory (PhASR) for determination of drug concentration and molecular analysis.

Eligibility Criteria:
Inclusion Criteria:

* Patients with vestibular schwannoma and/or meningioma diagnosed by MRI where surgical resection has been selected as treatment.
* Patients diagnosed with NF2 must meet Manchester Criteria.
* Age \> 18 years of age
* Prior biologic therapy, chemotherapy, surgery or radiation is permitted.
* At the time of screening, the patient must have normal organ and marrow function.
* Eastern Cooperative Oncology Group/World Health Organization (ECOG/WHO) performance status of 0-1.
* Patients must be able to swallow capsules.
* Patients or their legal representatives must be able to read, understand and provide informed consent to participate in the trial.
* Tumor type will be confirmed by a neuropathologist.
* Females of childbearing potential (FCBP) must have a negative serum or urine pregnancy test with a sensitivity of at least 50 mIU/mL prior to starting AR-42.
* The patient must be willing to comply with fertility requirements

Exclusion Criteria:

* Pregnant women are excluded from this study because the potential for teratogenic or abortifacient effects of AR-42 are not known. Because there is an unknown but potential risk for AEs in nursing infants secondary to treatment of the mother with AR-42, breastfeeding should be discontinued if the mother is treated with AR-42.
* Pediatric patients are excluded from the phase 0 study as the effects of AR-42 are not known on children and there is no potential direct benefit to them.
* Patients with malabsorption or any other condition that in the opinion of the principal investigator could cause difficulty in absorption of drug.
* Patients requiring chronic corticosteroids (dose equivalent \> 20mg prednisolone).
* Concurrent use of complementary or alternative medicines that in the opinion of the principal investigator would confound the interpretation of toxicities and/or antitumor activity of the study drug.
* Patients with a "currently active" second malignancy that, in the opinion of the principal investigator, will interfere with patient participation, increase patient risk, or confound data interpretation.
* Patients with a mean QTcB \> 450 msec in males and \> 470 msec in females.
* Patients with long QT syndrome.
* Patients who are being treated for an active infection.
* Patients receiving the following concomitant medications:

  * Any other anti-neoplastic chemotherapy or biologic therapy during the study
  * Concomitant radiotherapy
  * Concomitant HDAC inhibitors (e.g. valproic acid) as class-specific adverse reactions may be additive
  * Use of granulocyte colony-stimulating factors including G-CSF, pegylated G-CSF or GM-CSF should follow ASCO guidelines for patients receiving anti-cancer therapy.
  * Drugs associated with QT/QTc prolongation (see Appendix A)
* Patients who are receiving concurrent anti-neoplastic therapy.
* Any other medical condition, including mental illness or substance abuse, deemed by the principal investigator to likely interfere with a patient's ability to sign informed consent, cooperate and participate in the study, or interfere with the interpretation of the results.
* Patients with significant cardiovascular disease, including a myocardial infarction or unstable angina within 6 months or unstable cardiac arrhythmias are not eligible for the study.
* Known HIV infection, as their immunosuppressive conditions may complicate potential pancytopenias seen with HDAC inhibitors and complicate evaluation of drug effect.