An Early Phase Study of NEI-01 in Patients With Solid Tumors or Acute Myeloid Leukemia

Inclusion Criteria: 1. The subject must be capable of giving written informed consent. 2. Confirmed diagnosis of advanced solid tumor or relapsed/refractory AML as detailed below: 1. For Part 1 and 2 (Cohort 1): Histologically or cytologically confirmed diagnosis of any locally advanced or metastatic solid tumor 2. For Part 2 (Cohort 2): Histologically or cytologically confirmed diagnosis of relapsed or refractory AML as defined by World Health Organisation (WHO) classification 3. Existence of all of the following medical conditions or diagnoses: For Solid Tumor Population: 1. At least one measurable target lesion at screening, as defined by RECIST 1.1; 2. Life expectancy ≥ 12 weeks at screening; 3. ECOG performance status of 0 or 1 at screening; 4. Adequate bone marrow function at screening, as defined by: Hb ≥ 8 g/dL; ANC ≥ 1.5 × 109/L; AND Platelet count ≥ 75× 109/L; 5. Adequate coagulation function at screening, as defined by: PT or INR ≤ 1.5 × ULN; AND aPTT ≤ 1.5 × ULN; 6. Adequate liver function at screening, as defined by: Total bilirubin ≤ 1.5 × ULN; AND AST and ALT ≤ 2.5 × ULN OR ≤ 5 × ULN; 7. Adequate renal function at screening, as defined by: Creatinine ≤ 1.5 × ULN; OR Creatinine clearance ≥ 50 mL/min. For Part 2 (Cohort 2) - AML Population: 1. Life expectancy ≥ 12 weeks at screening; 2. ECOG performance status ≤ 2 at screening; 3. Adequate liver function at screening, as defined by: Total bilirubin ≤ 1.5× ULN; AND AST and ALT ≤ 3 ULN; 4. Adequate renal function at screening, as defined by: Creatinine ≤ 1.5 × ULN; OR Creatinine clearance ≥ 30 mL/min (by the Cockcroft Gault method). 4. Willingness and agreement to undertake measures to avoid pregnancy of the subject or the subject's sexual partner(s) 5. A female subject must be willing and agree to avoid engagement in breastfeeding. 6. Willingness and agreement to avoid blood donation. Exclusion Criteria: 1. History of any of the following diseases or conditions: 1. Previous or concurrent active cancer that is distinct in primary site or histology from the cancer being evaluated in this study; 2. Known CNS metastasis(es), unless the metastasis(es) was/were treated and became stable and the subject does not require systemic corticosteroids for management of CNS symptoms for at least 14 days prior to the first dose of study intervention; 3. Any history of or current active cardiac disease or dysfunction; 4. Known history of HIV infection; 5. Known history of active HBV infection; 6. Known history of active HCV infection. 2. Existence of any of the following medical conditions or diagnoses: 1. Positive pregnancy test; 2. Active infection requiring treatment by systemic therapy; 3. Any unresolved toxicity related to any prior therapy of ≥ Grade 2 (as defined by NCI CTCAE v5.0) prior to the first dose of the study intervention. 3. Use of any of the following prior or concomitant medications, therapies or interventions: 1. Prior treatment with ADI-PEG-20 or another experimental arginine deprivation strategy; 2. Any anti-cancer therapy within 21 days prior to the first dose of the study intervention and/or during the subject's participation in the study; 3. Any surgery within 28 days prior to the first dose of the study intervention. 4. Prior or concurrent participation in any other clinical study 5. Any clinically significant concomitant disease or condition that, in the reasonable opinion of the investigator, may interfere with the subject's participation in this study or pose an unacceptable safety risk for the subject's participation in this study.