A Phase 1/2 Study of AEB1102 in Patients With Arginase I Deficiency

Inclusion Criteria: * Documented diagnosis of Arginase I deficiency * Adequate organ function: Hgb ≥ 10 g/dL, ANC ≥ 1.5 x 109/L, plt count ≥ 100,000/µL; liver transaminase levels ≤ 2.5x ULN, total bilirubin ≤ 2.0 mg/dL; serum creatinine \<1.5 x ULN * If female and of child-bearing potential, has a negative serum pregnancy test within 7 days before enrollment * If a sexually active (male or female), must be surgically sterile, post-menopausal (female), or must agree to use a physician-approved method of birth control during the study and for a minimum of 30 days after the last study drug administration * Patient or legal guardian is able and willing to provide written informed consent and to comply with all requirements of study participation (including all study procedures and continuation of prescribed diet without modification) prior to any screening procedures Exclusion Criteria: * Transfusion of ≥ 2 u RBC within 60 days * Active infection requiring systemic treatment * Known infection with HIV, Hep B or Hep C * Severe hyperammonemia requiring hospitalization within 14 days. Had more than one episode of hyperammonemia requiring hospitalization within the 30 days prior to enrollment. * Current uncontrolled hyperammonemia * Has a history of hypersensitivity to PEG or any other component of the AEB1102 (Co-ArgI-PEG) formulation * If female, is lactating or breast feeding PART 2 INCLUSION CRITERION: 1\. Did not experience any safety or tolerability event in Part 1 which would preclude continued participation and dosing of AEB1102