A Study of Ad-RTS-hIL-12 With Veledimex in Combination With Nivolumab in Subjects With Glioblastoma; a Substudy to ATI001-102

Eligible patients will receive one dose of nivolumab, via infusion, one week prior to
standard of care craniotomy and tumor resection (subtotal or total). On the day of surgery,
patients will receive one dose of veledimex before the resection procedure. Ad-RTS-hIL-12
will be administered by free-hand injection. Patients will continue on oral veledimex for 14
days. Following veledimex, patients will receive nivolumab via infusion every two weeks.

The study is divided into three periods: the screening period, the treatment period and the
follow-up period.

Inclusion Criteria:

- Male or female subject ≥18 and ≤75 years of age

- Provision of written informed consent for tumor resection, stereotactic surgery, tumor
biopsy, samples collection, and treatment with investigational products prior to
undergoing any study specific procedures

- Histologically confirmed supratentorial glioblastoma

- Evidence of tumor recurrence/progression by magnetic resonance imaging (MRI) according
to response assessment in neuro-oncology (RANO) criteria after standard initial
therapy

- Previous standard-of-care antitumor treatment including surgery and/or biopsy and
chemoradiation. At the time of registration, subjects must have recovered from the
toxic effects of previous treatments as determined by the treating physician. The
washout periods from prior therapies are intended as follows: (windows other than what
is listed below should be allowed only after consultation with the Medical Monitor)

1. Nitrosureas: 6 weeks

2. Other cytotoxic agents: 4 weeks

3. Antiangiogenic agents, including bevacizumab: 4weeks

4. Targeted agents, including small molecule tyrosine kinase inhibitors: 2 weeks

5. Vaccine-based therapy: 3 months

- Able to undergo standard MRI scans with contrast agent before enrollment and after
treatment

- Karnofsky Performance Status ≥70%

- Adequate bone marrow reserves and liver and kidney function, as assessed by the
following laboratory requirements:

1. Hemoglobin ≥9 g/L

2. Lymphocytes >500/mm3

3. Absolute neutrophil count ≥1500/mm3

4. Platelets ≥100,000/mm3

5. Serum creatinine ≤1.5 x upper limit of normal (ULN)

6. Aspartate transaminase (AST) and alanine transaminase (ALT) ≤2.5 x ULN. For
subjects with documented liver metastases, ALT and AST ≤5 x ULN

7. Total bilirubin < 1.5 x ULN

8. International normalized ratio (INR) and aPTT within normal institutional limits

- Male and female subjects must agree to use a highly reliable method of birth control
(expected failure rate <5% per year) from the Screening Visit through 28 days after
the last dose of study drug. Women of childbearing potential (perimenopausal women
must be amenorrheic for at least 12 months to be considered of non-childbearing
potential) must have a negative pregnancy test at screening.

- Normal cardiac and pulmonary function as evidenced by a normal ECG and peripheral
oxygen saturation (SpO2) ≥90% by pulse oximetry

Exclusion Criteria:

- Previous treatment with inhibitors of immunocheckpoint pathways (eg, anti-PD-1,
anti-PD-L1, anti-PD-L2, anti-CD137, or anti-CTLA-4 antibody) or other agents
specifically targeting T cells

- Radiotherapy treatment within 4 weeks or less prior to veledimex dosing

- Subjects with clinically significant increased intracranial pressure (eg, impending
herniation or requirement for immediate palliative treatment) or uncontrolled seizures

- Known immunosuppressive disease, or autoimmune conditions, and/or chronic viral
infections (eg, human immunodeficiency virus [HIV], hepatitis)

- Use of systemic antibacterial, antifungal, or antiviral medications for the treatment
of acute clinically significant infection within 2 weeks of first veledimex dose.
Concomitant therapy for chronic infections is not allowed. Subjects must be afebrile
prior to Ad-RTS-hIL-12 injection; only prophylactic antibiotic use is allowed
perioperatively.

- Use of enzyme inducing antiepileptic drugs (EIAED) within 7 days prior to the first
dose of study drug. Note: Levetiracetam (Keppra®) is not an EIAED and is allowed.

- Other concurrent clinically active malignant disease, requiring treatment, with the
exception of non-melanoma cancers of the skin or carcinoma in situ of the cervix or
nonmetastatic prostate cancer

- Nursing or pregnant females

- Prior exposure to veledimex

- Use of medications that induce, inhibit, or are substrates of cytochrome p450 (CYP450)
3A4 within 7 days prior to veledimex dosing without consultation with the Medical
Monitor

- Presence of any contraindication for a neurosurgical procedure

- Unstable or clinically significant concurrent medical condition that would, in the
opinion of the Investigator or Medical Monitor, jeopardize the safety of a subject
and/or their compliance with the protocol. Examples include, but are not limited to:
unstable angina, congestive heart failure, myocardial infarction within 2 months of
screening, ongoing maintenance therapy for life-threatening ventricular arrhythmia or
uncontrolled asthma.

- History of myocarditis or congestive heart failure (as defined by New York Heart
Association Functional Classification III or IV), as well as unstable angina, serious
uncontrolled cardiac arrhythmia, uncontrolled infection, or myocardial infarction 6
months prior to study entry.