Dataset from A Phase 2a Study to Evaluate the Safety and Tolerability of OCR-002 (Ornithine Phenylacetate) in the Treatment of Patients With Acute Liver Failure/Severe Acute Liver Injury

This Phase 2a clinical study is designed to provide data on OCR-002 in patients with acute
liver failure/acute liver injury (ALF/ALI) in regard to:

- safety and tolerability;

- metabolism of the compound to glutamine and phenylacetylglutamine (PAGN);

- its effect on circulating ammonia levels and neurological function in patients with and
without impaired renal function after continuous infusion at different infusion rates.

Subjects will receive up to 120 hours (5 days) of drug infusion, followed by a 30 day
follow-up visit post infusion. It is anticipated that this early safety and tolerability
study, with appropriate PK/PD data, will lead to a development program for the use of OCR-002
in the treatment of hyperammonemia either due to ALF or possibly other liver conditions. The
hypotheses are:

- Treatment with OCR-002 is safe and tolerable in patients with acute liver failure/acute
liver injury due to acetaminophen overdose or drug-induced liver injury, autoimmune
hepatitis, viral hepatitis or indeterminate etiologies.

- A dose of 10-20g/24h (0.42-.83g/h) will achieve steady state plasma concentrations
within 6-12h with little additional accumulation in the ALI/ALF setting.

- Treatment with OCR-002 will reduce ammonia and improve neurological function in patients
with acute liver failure/severe acute liver injury.