This is a Phase 1, open-label, dose escalation study of JVRS-100. The study will proceed in 2 stages to minimize the number of patients treated at doses substantially below the recommended phase 2 dose. In stage 1, an accelerated titration schema will be followed with one patient at each dose level. Stage 2 will commence after a dose limiting toxicity is observed in stage 1 or after the maximum dose for stage 1 is reached. Stage 2 will follow a modified Fibonacci schema with 3-6 subjects at each dose level until a recommended phase 2 dose is determined. The cohort will then be expanded to a maximum of 12 patients to more fully evaluate the recommended phase 2 dose.

This is a Phase 1, open-label, dose escalation study of JVRS-100. The study will proceed in 2 stages to minimize the number of patients treated at doses substantially below the recommended phase 2 dose. In stage 1, cohorts of three will be treated at each dose level however doses will be doubled from level to level. Stage 2 will commence after a dose limiting toxicity is observed in stage 1 or after the maximum dose for stage 1 is reached. Stage 2 will follow a modified Fibonacci schema with 3-6 subjects at each dose level until a recommended phase 2 dose is determined. The cohort will then be expanded to a maximum of 12 patients to more fully evaluate the recommended phase 2 dose. The Principal Investigator will assign dose level to be administered to all patients.

Inclusion Criteria:

• 18 years of age
• Histologically or cytologically documented relapsed or refractory acute leukemia
• Unlikely to benefit from standard therapy in the opinion of the investigator or refuse standard therapy
• ECOG performance status 0-2
• Adequate renal and hepatic function
• No hematologic criteria for WBC, Hbg or platelets
• Negative virology screen for HIV, hepatitis B surface antigen & hepatitis C
• Female patients of childbearing potential must have a negative serum pregnancy test
• Male & female patients must agree to use a medically acceptable barrier and/or chemical contraceptive method during the study and for a minimum of 3 months afte the last dose of study treatment.
• Patients post blood or marrow transplant should demonstrate a circulating CD8 count of at lest 200 cells/ul

Exclusion Criteria:

• Active CNS leukemia
• Current concomitant chemotherapy, radiation therapy or immunotherapy
• Receipt of any investigational agent within 28 days of first dose of JVRS-100
• Persistent clinically significant toxicity from prior anticancer therapy that is > Grade 2 (NCI CTCAE v3.0)
• Bone marrow or stem cell transplant within 3 months prior to first dose of JVRS-100
• Chronic administration of immunosuppressive agents within 14 days of first dose of JVRS-100. Use of inhaled steroids, nasal sprays, eye drops, and topical creams for small body areas is allowed.
• Pregnant or lactating
• History of prior malignancy other than leukemia within the past 5 years, excluding basal or squamous cell carcinoma of the skin or carcinoma in situ of the cervix
• Patients with a systemic fungal, bacterial, viral, or other infection not controlled
• Any condition which, in the opinion of the investigator, would compromise patient safety or compliance, interfere with consent, study participation, follow up, or interpretation of study results