Window of Opportunity Study of DSP-0390 in Gliomas

- Radiologically suspected lower grade glioma, or histologically confirmed recurrent/residual grade II and III IDH-mutant gliomas.

- Patient must be a candidate for surgical resection where the estimated resected tumor volume would be at least 8 cc.

- At least 18 years of age.

- Karnofsky ≥ 70%

- Adequate bone marrow and organ function as defined below:

- If a patient is using an antiepileptic medication, the patient is on a stable dose and without seizures for 14 days prior to Day 1. The antiepileptic medication used must not fall under any prohibited therapy category as defined in the protocol.

- If the patient is receiving corticosteroids at baseline, the dose administered is stable or decreasing for at least 5 days prior to Day 1. A higher stable dose of corticosteroids, if used as hormone replacement therapy, may be allowed upon discussion with the sponsor-investigator.

- The effects of DSP-0390 on the developing human fetus are unknown. For this reason, women of childbearing potential and men must agree to use adequate contraception (hormonal or barrier method of birth control, abstinence) prior to study entry, for the duration of study participation, and for 6 months after the last dose of study drug. Should a woman become pregnant or suspect she is pregnant while participating in this study, she must inform her treating physician immediately.

- Ability to understand and willingness to sign an IRB approved written informed consent document.

- Patient has had prior therapy with bevacizumab or other anti-vascular endothelial growth factor (VEGF) treatments within 3 months prior to Day 1.

- Patient has multifocal disease, leptomeningeal metastasis, or extracranial metastasis.

- Patient has a clinically significant abnormal ECG, including those where QT prolongation (QTcF >450 msec for males and >470 msec for females); and/or the patient has a history of Torsade de Pointes.

- Patient is known to have dysphagia, short-gut syndrome, gastroparesis, or other condition that may limit the ingestion or gastrointestinal absorption of drugs administered orally.

- Patient is known to have active Crohn's or other inflammatory bowel disease.

- A history of other malignancy for which all treatment was completed at least 2 years before Day 1 and the patient has no evidence of disease. Exceptions include non-melanoma skin cancer, cervical carcinoma in situ, and superficial bladder cancer that has been removed or curatively treated.

- Currently receiving any other investigational agents.

- A history of allergic reactions attributed to compounds of similar chemical or biologic composition to DSP-0390.

- Patient has taken concurrent use of prohibited medications: carbamazepine, phenytoin, phenobarbital, and other strong or moderate CYP3A4 inhibitors or inducers, and strong CYP2D6 inhibitors within 1 week or 5 half-lives (whichever is greater) prior to Day 1 or expects to use them during the study.

- The presence of any active retinal abnormality determined by screening ophthalmologic examination.

- Patient has significant cardiovascular disease, including New York Heart Association (NYHA) Class III or IV congestive heart failure, myocardial infarction, unstable angina, poorly controlled cardiac arrhythmias, or stroke in the preceding 6 months prior to Day 1.

- Uncontrolled intercurrent illness including, but not limited to, psychiatric illness/social situations that would limit compliance with study requirements, disorders associated with significant immunocompromised state, ongoing or active infection, symptomatic congestive heart failure, unstable angina pectoris, or cardiac arrhythmia.

- Pregnant and/or breastfeeding. Women of childbearing potential must have a negative serum pregnancy test within 7 days prior to the first dose of DSP-0390.

- Patients with HIV are eligible unless their CD4+ T-cell counts are <350 cells/mcL or they have a history of AIDS-defining opportunistic infection within the 12 months prior to registration. Concurrent treatment with effective ART according to DHHS treatment guidelines is recommended. Recommend exclusion of specific ART agents based on predicted drug-drug interactions (i.e. for sensitive CYP3A4 substrates, concurrent strong CYP3A4 inhibitors (ritonavir and cobicistat) or inducers (efavirenz) should be contraindicated.

- Patient has a known detectable viral load for hepatitis C, or evidence of a hepatitis B surface antigen, all being indicative of active infection.

- Patient has had a major surgical procedure, surgical resection, open biopsy, or significant traumatic injury within 4 weeks prior to Day 1 or anticipates needing a major surgical procedure during the course of the study.

- Patient has had a minor surgical procedure, fine needle aspirations, or core biopsies within 7 days prior to Day 1.

- Patient has evidence of central nervous system hemorrhage on baseline MRI or CT scan (except for postsurgical, asymptomatic, Grade 1 hemorrhage that has been stable for at least 4 weeks for enrolled patients).

- Patient has received chemotherapy or investigational anticancer therapy within 4 weeks (except 6 weeks for nitrosoureas and immunotherapy, or 8 weeks for an implanted nitrosoureas wafer) prior to Day 1.

- Patient has had radiotherapy within 12 weeks prior to Day 1, unless relapse is confirmed by tumor biopsy or new lesion outside of radiation field, or if there are 2 MRIs (performed 8 weeks apart) confirming progressive disease.