This Study is to Evaluate OBI-3424 Safe and Effective Treatment Dose in Subjects With Hepatocellular Carcinoma or Castrate Resistant Prostate Cancer

Inclusion Criteria:

1. At least 18 years of age

2. Ability to understand the purposes and risks of the study and has signed a written
informed consent form approved by the investigator's Institutional Review Board
(IRB)/Independent Ethics Committee (IEC)

3. Recovered from toxicities of prior therapy to Grade 0 or 1

4. Measurable disease by Response Evaluation Criteria in Solid Tumors (RECIST version
1.1) criteria or for rising prostate specific antigen (PSA) according to the Prostate
Cancer Working Group 3 (PCWG3) criteria for subjects with CRPC

5. Available tissue (including archival tissue) for retrospective AKR1C3 expression
analysis (except for subjects with CRPC where this is not a requirement for inclusion)

6. Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1

7. Cardiac QTcF interval ≤ 450msec for males and ≤470 msec for females

8. Acceptable liver function:

1. Bilirubin ≤1.5 × institutional ULN

2. AST and ALT ≤3.0 × ULN, or ≤5.0 × ULN for subjects with liver involvement

9. Acceptable renal function:

a. Creatinine clearance >30 mL/min according to the Cockcroft-Gault formula

10. Acceptable hematologic status (without hematologic support):

1. ANC ≥1500 cells/μL

2. Platelet count ≥100,000/μL

3. Hemoglobin ≥9.0 g/dL

11. Females of childbearing potential must not have had unprotected sexual intercourse
within 30 days before study entry and must agree to use a highly effective method of
contraception (e.g., total abstinence, an intrauterine device, a double-barrier method
[such as condom plus diaphragm with spermicide], a contraceptive implant, an oral
contraceptive, or have a vasectomized partner with confirmed azoospermia) throughout
the entire study period and for 30 days after study drug discontinuation.

Exclusion Criteria:

1. Prior radiotherapy to more than 25% of the bone marrow

2. Symptomatic brain metastases, unless previously treated and well controlled for at
least 4 weeks after central nervous system (CNS)-directed treatment as ascertained by
clinical examination and brain imaging (magnetic resonance imaging [MRI] or computed
tomography [CT]) during the Screening Period. Patients with known leptomeningeal
disease are excluded.

3. Previously treated malignancies, except for adequately treated non-melanoma skin
cancer, in situ cancer, or other cancers whose natural history or treatment does not
have the potential to interfere with the safety or efficacy assessment of the current
study

4. Major surgery, other than diagnostic surgery, within 4 weeks prior to Day 1, without
complete recovery

5. Active, uncontrolled bacterial, viral, or fungal infections, requiring systemic
therapy

6. Treatment with radiation therapy, surgery, chemotherapy, targeted therapies or
hormones within 3 weeks prior to study entry (6 weeks for nitrosoureas or mitomycin C)

7. Concomitant use of strong CYP3A4 inhibitors/inducers

8. Subjects who participated in an investigational drug or device study within 28 days
prior to study entry

9. Subjects with known HIV infection, unless CD4 ≥500 cells/μL and HIV RNA below the
limit of detection on stable doses of antiretroviral therapy

10. Subjects with chronic HBV infection, unless Screening viral load <100 IU/mL on stable
doses of antiviral therapy. Note: Subjects with chronic HCV infection are allowed to
enroll in the study but do not have a defined maximum viral load requirement for study
entry.

11. Females who are pregnant or breast-feeding

12. Concomitant disease or condition that could interfere with the conduct of the study,
or that would, in the opinion of the investigator, pose an unacceptable risk to the
subject in this study

13. Unwillingness or inability to comply with the study protocol for any reason