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Safety Study of Ornithine Phenylacetate to Treat Patients With Acute Liver Failure/Severe Acute Liver Injury

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

Status
Completed
Phases
Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT01548690
Acronym
STOP-ALF
Enrollment
47
Registered
2012-03-08
Start date
2012-06-30
Completion date
2017-02-23
Last updated
2018-10-30

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Acute Liver Failure, Acute Liver Injury

Keywords

ornithine, phenylacetate, acetaminophen toxicity, acute liver failure, hepatitis B, autoimmune hepatitis, drug-induced liver injury

Brief summary

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.

Detailed description

There is strong experimental and clinical rationale for the use of ammonia-lowering therapies in ALF. Ammonia is normally produced in the gut and transformed by the liver into urea. As the liver fails, ammonia increases in the systemic circulation and enters into the brain. The result of a rapid rise in ammonia or related compounds in the cerebral circulation is hepatic encephalopathy (HE), a reversible neuropsychiatric condition that ranges in severity from mild impairment in attention, to delirium, the development of cerebral edema, coma and death. This is a Phase 2a, multi-center, open-label study, conducted in two cohorts in patients diagnosed with acute liver failure/acute liver injury (ALF/ALI) who meet inclusion/exclusion criteria. This study is designed to provide data on OCR-002 with regards to * the effect on circulating ammonia levels in patients with acute liver failure with and without impaired renal function at different doses after single and continuous infusion * safety and dose tolerability as well as * providing data on the metabolites, glutamine and phenylacetylglutamine in this patient population. It is anticipated that this early efficacy, safety, tolerability, Pharmacokinetic/Pharmacodynamic (PK/PD) and dose-ranging study will lead to a Phase 3 development program for the use of OCR-002 in the treatment of hyperammonemia due to ALF. No clinical outcome measures will be formally studied because of the small sample size.

Interventions

Up to 36 patients will be enrolled into 2 groups \[\ 18 with minimal renal dysfunction (Cohort 1) & \ 18 w/ comprised renal function (Cohort 2)\] and receive OCR-002 infusion for at least 72 hrs. OCR-002 will be administered in the vein and pharmacokinetics (pk) assessed for all subjects who receive the infusion. The first 24 enrolled subjects received OCR-002 at 3 ascending dose levels (DLs 1-3) with a maximum target infusion rate equivalent to 10g/24h. The remaining 12 patients (\ 6 Cohort 1 & \ 6 Cohort 2) will be enrolled and receive identical quantities of OCR-002 at 20g/24hr continuously for 5 days (Dose Level 4).

Sponsors

Medical University of South Carolina
CollaboratorOTHER
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
CollaboratorNIH
Ocera Therapeutics
CollaboratorINDUSTRY
William Lee
Lead SponsorOTHER

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
No

Inclusion criteria

1. Men and women, ages 18-65 (have not reached their 66th birthday). 2. Acute liver failure, defined as the development of coagulopathy (International normalized ratio \[INR\] ≥1.5) with encephalopathy in a patient with no prior history of liver disease, with onset of symptoms within 28 days of the inciting event. Patients may have either a history of acetaminophen overdose (defined as \>4 g/day within 7 days of presentation) and/or detectable acetaminophen levels in the serum, with a pattern of liver function tests typical for acetaminophen toxicity (bilirubin \< 10 mg/dL and alanine aminotransferase (ALT) ≥1000 IU/L), or a diagnosis of hepatitis A, hepatitis B, drug-induced liver injury, autoimmune hepatitis or indeterminate cause based on standard criteria. 3. ALI patients may also be enrolled (those meeting the above criteria plus coagulopathy (INR ≥ 2.0) and no evidence of encephalopathy) 4. Written informed consent from the patient (ALI) or patient's legally authorized representative or family member if he/she is considered encephalopathic (ALF). 5. Ammonia level ≥60 μmol/L at baseline (within 8h prior to T0/initiation of infusion). 6. Serum creatinine levels as follows: 1. Cohort 1: Creatinine ≤1.5 mg/dL; and 2. Cohort 2: Creatinine \>1.5 mg/dL and \<10mg/dL. 7. Mean arterial pressure of \>65 mmHg.

Exclusion criteria

1. History of chronic liver disease. 2. Signs of overt cerebral herniation, or uncontrolled intracranial hypertension by intracranial pressure (ICP) monitoring (if applicable). 3. Evidence of Wilson's disease, alcoholic hepatitis, biliary obstruction, ischemic hepatitis, severe acute renal tubular necrosis (ATN) due to shock, or any patient with ongoing hypotension. 4. Significant gastrointestinal bleeding (coffee grounds per nasogastric tube and/or melena). 5. Hemodynamic instability, defined by a mean arterial pressure of \<65 mmHg. 6. Cardiopulmonary complications such as pulmonary edema, aspiration pneumonia, heart failure. 7. QT interval of \>500msec at baseline EKG. 8. Pregnancy. 9. History of malignancy that has not been cured or any cancer in remission for less than 1 within the past 5 year. Non-melanoma skin cancers do not preclude participation in the trial. 10. Concomitant administration of drugs known to interfere with renal excretion of phenylacetylglutamine or those medications that may induce hyperammonemia such as haloperidol, valproic acid and systemic corticosteroids (prohibited during the study). Alternative ammonia modifying agents such as lactulose and rifaximin are not considered standard of care and are prohibited during the study period. 11. Any other health condition that would preclude participation in the study in the judgment of the principal investigator.

Design outcomes

Primary

MeasureTime frameDescription
Number of Participants That do Not Tolerate the Administered Dose and Had Grade 3 or 4 Treatment Emergent Adverse Events as a Measure of Safety and Tolerability30 DaysTo evaluate the safety and tolerability of OCR-002 in patients with acute liver failure/severe acute liver injury

Secondary

MeasureTime frameDescription
Measurement of OCR-002 Plasma Concentration24 Hours after last infusionTo evaluate the steady state pharmacokinetic and pharmacodynamic profile of OCR-002 in patients with impaired and intact renal function using urinary phenylacetylglutamine (PAGN) as a surrogate marker
Change in AmmoniaBaseline and 72 HoursTo evaluate the effect of OCR-002 on ammonia levels in patients with acute liver failure/severe acute liver injury
Neurological Function Measured by the West Haven Criteria (WHC) for Hepatic Encephalopathy120 hours from start of infusionThe West Haven Criteria (WHC) for Hepatic Encephalopathy measures the severity of encephalopathy and patient's level of consciousness. The scale ranges from 0 to 4; a minimum score of 0 represents a better outcome, and a maximum total score of 4 represents a worse outcome. A score of 0 corresponds to normal consciousness and behavior and normal neurological examination. A score of 1 corresponds to mild lack of awareness, shortened attention span, and impaired addition or subtraction; mild asterixis or tremor. A score of 2 corresponds to lethargy, disorientated or inappropriate behavior, obvious asterixis; slurred speech. A score of 3 corresponds to somnolent but arousable, gross disorientation or bizarre behavior, muscle rigidity and clonus; hyperreflexia. A score of 4 corresponds to coma and decerebrate posturing.
Neurological Function Measured by the Orientation Log (O-log)30 DaysThe orientation log focuses on orientation to place, time, and circumstance. There are 10 items on the orientation log, which are scored 0-3. A spontaneous correct response is awarded 3 points. A spontaneous response that is lacking or incorrect, but a correct response is provided following a logical cue is awarded 2 points. A score of 1 is given if spontaneous and cued responses are lacking or incorrect, but a correct response is provided in a recognition format. A score of 0 is given if the spontaneous, cued, or recognition format does not generate a correct answer. Scores from the 10 items are summed and the final score ranges from 0 to 30.

Countries

United States

Participant flow

Participants by arm

ArmCount
Maximum Dose Level 3.33 g/24h
Initial infusion of study drug at 0.139 g/h for the first 12 hours (approximately 3.33 g/24h) and maintained at this rate for up to 120 hours.
9
Maximum Dose Level 6.65 g/24h
Initial infusion of study drug at a dose of 0.139 g/h for the first 12 hours (approximately 3.33 g/24h); dose increased to 0.277 g/h for the remaining 108 hours (approximately 6.65 g/24h) for a total treatment period of up to 120 hours.
10
Maximum Dose Level 10 g/24h
Initial infusion of study drug at a dose of 0.139 g/h for the first 12 hours (approximately 3.33 g/24h); dose increased to 0.277 g/h for the next 12 hours; dose then increased to 0.416 g/h (approximately 10 g/24h) and maintained at this rate for the remaining 96 hours for a total treatment period of up to 120 hours.
13
Maximum Dose Level 20g/24h
Study drug infused at a dose of 20g/24h from initiation of infusion for up to 120 hours.
15
Total47

Baseline characteristics

CharacteristicTotalMaximum Dose Level 20g/24hMaximum Dose Level 10 g/24hMaximum Dose Level 6.65 g/24hMaximum Dose Level 3.33 g/24h
Age, Continuous35.0 years35.0 years42.0 years30.0 years32.0 years
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
Asian
2 Participants0 Participants2 Participants0 Participants0 Participants
Race (NIH/OMB)
Black or African American
11 Participants5 Participants2 Participants3 Participants1 Participants
Race (NIH/OMB)
More than one race
0 Participants0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
Unknown or Not Reported
2 Participants0 Participants1 Participants0 Participants1 Participants
Race (NIH/OMB)
White
32 Participants10 Participants8 Participants7 Participants7 Participants
Region of Enrollment
United States
47 Participants15 Participants13 Participants10 Participants9 Participants
Sex: Female, Male
Female
31 Participants11 Participants9 Participants5 Participants6 Participants
Sex: Female, Male
Male
16 Participants4 Participants4 Participants5 Participants3 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
EG002
affected / at risk
EG003
affected / at risk
deaths
Total, all-cause mortality
2 / 93 / 102 / 134 / 15
other
Total, other adverse events
8 / 95 / 109 / 137 / 15
serious
Total, serious adverse events
5 / 93 / 104 / 134 / 15

Outcome results

Primary

Number of Participants That do Not Tolerate the Administered Dose and Had Grade 3 or 4 Treatment Emergent Adverse Events as a Measure of Safety and Tolerability

To evaluate the safety and tolerability of OCR-002 in patients with acute liver failure/severe acute liver injury

Time frame: 30 Days

Population: All patients who consented to the study, completed screening and had the intravenous infusion of study drug initiated

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Maximum Dose Level 3.33 g/24hNumber of Participants That do Not Tolerate the Administered Dose and Had Grade 3 or 4 Treatment Emergent Adverse Events as a Measure of Safety and Tolerability0 Participants
Maximum Dose Level 6.65 g/24hNumber of Participants That do Not Tolerate the Administered Dose and Had Grade 3 or 4 Treatment Emergent Adverse Events as a Measure of Safety and Tolerability0 Participants
Maximum Dose Level 10 g/24hNumber of Participants That do Not Tolerate the Administered Dose and Had Grade 3 or 4 Treatment Emergent Adverse Events as a Measure of Safety and Tolerability0 Participants
Maximum Dose Level 20g/24hNumber of Participants That do Not Tolerate the Administered Dose and Had Grade 3 or 4 Treatment Emergent Adverse Events as a Measure of Safety and Tolerability0 Participants
Secondary

Change in Ammonia

To evaluate the effect of OCR-002 on ammonia levels in patients with acute liver failure/severe acute liver injury

Time frame: Baseline and 72 Hours

Population: All patients who consented to the study and had the intravenous infusion of study drug initiated for up to 72 hours and available venous or arterial ammonia levels.

ArmMeasureValue (MEAN)Dispersion
Maximum Dose Level 3.33 g/24hChange in Ammonia41.2 Percent ChangeStandard Deviation 21.1
Maximum Dose Level 6.65 g/24hChange in Ammonia16.6 Percent ChangeStandard Deviation 51.4
Maximum Dose Level 10 g/24hChange in Ammonia41.8 Percent ChangeStandard Deviation 35.8
Maximum Dose Level 20g/24hChange in Ammonia38.4 Percent ChangeStandard Deviation 31.1
Secondary

Measurement of OCR-002 Plasma Concentration

To evaluate the steady state pharmacokinetic and pharmacodynamic profile of OCR-002 in patients with impaired and intact renal function using urinary phenylacetylglutamine (PAGN) as a surrogate marker

Time frame: 24 Hours after last infusion

Population: All patients who consented to the study and had the intravenous infusion of study drug initiated for up to 120 hours and had results available from serum and urine samples measuring the pharmacokinetic (PK), pharmacodynamic profile (phenylacetic acid (PAA), ornithine) and urinary phenylacetylglutamine (PAGN) levels.

ArmMeasureValue (MEAN)Dispersion
Maximum Dose Level 3.33 g/24hMeasurement of OCR-002 Plasma Concentration65.6 micrograms per millileterStandard Deviation 82.5
Maximum Dose Level 6.65 g/24hMeasurement of OCR-002 Plasma Concentration32.2 micrograms per millileterStandard Deviation 31.4
Maximum Dose Level 10 g/24hMeasurement of OCR-002 Plasma Concentration33.4 micrograms per millileterStandard Deviation 24.1
Maximum Dose Level 20g/24hMeasurement of OCR-002 Plasma Concentration104.9 micrograms per millileterStandard Deviation 104.5
Secondary

Neurological Function Measured by the Orientation Log (O-log)

The orientation log focuses on orientation to place, time, and circumstance. There are 10 items on the orientation log, which are scored 0-3. A spontaneous correct response is awarded 3 points. A spontaneous response that is lacking or incorrect, but a correct response is provided following a logical cue is awarded 2 points. A score of 1 is given if spontaneous and cued responses are lacking or incorrect, but a correct response is provided in a recognition format. A score of 0 is given if the spontaneous, cued, or recognition format does not generate a correct answer. Scores from the 10 items are summed and the final score ranges from 0 to 30.

Time frame: 30 Days

Population: All patients who consented to the study and had the intravenous infusion of study drug initiated and Orientation log (O-log) assessment scores available.

ArmMeasureValue (MEAN)Dispersion
Maximum Dose Level 3.33 g/24hNeurological Function Measured by the Orientation Log (O-log)23.8 units on a scaleStandard Deviation 0.4
Maximum Dose Level 6.65 g/24hNeurological Function Measured by the Orientation Log (O-log)24.0 units on a scaleStandard Deviation 0
Maximum Dose Level 10 g/24hNeurological Function Measured by the Orientation Log (O-log)24.0 units on a scaleStandard Deviation 0
Maximum Dose Level 20g/24hNeurological Function Measured by the Orientation Log (O-log)24.0 units on a scaleStandard Deviation 0
Secondary

Neurological Function Measured by the West Haven Criteria (WHC) for Hepatic Encephalopathy

The West Haven Criteria (WHC) for Hepatic Encephalopathy measures the severity of encephalopathy and patient's level of consciousness. The scale ranges from 0 to 4; a minimum score of 0 represents a better outcome, and a maximum total score of 4 represents a worse outcome. A score of 0 corresponds to normal consciousness and behavior and normal neurological examination. A score of 1 corresponds to mild lack of awareness, shortened attention span, and impaired addition or subtraction; mild asterixis or tremor. A score of 2 corresponds to lethargy, disorientated or inappropriate behavior, obvious asterixis; slurred speech. A score of 3 corresponds to somnolent but arousable, gross disorientation or bizarre behavior, muscle rigidity and clonus; hyperreflexia. A score of 4 corresponds to coma and decerebrate posturing.

Time frame: 120 hours from start of infusion

Population: All patients who consented to the study and had the intravenous infusion of study drug initiated and West Haven Criteria (WHC) for Hepatic Encephalopathy assessment scores available.

ArmMeasureValue (MEAN)Dispersion
Maximum Dose Level 3.33 g/24hNeurological Function Measured by the West Haven Criteria (WHC) for Hepatic Encephalopathy2.4 units on a scaleStandard Deviation 1.9
Maximum Dose Level 6.65 g/24hNeurological Function Measured by the West Haven Criteria (WHC) for Hepatic Encephalopathy3.2 units on a scaleStandard Deviation 2
Maximum Dose Level 10 g/24hNeurological Function Measured by the West Haven Criteria (WHC) for Hepatic Encephalopathy1.6 units on a scaleStandard Deviation 1.4
Maximum Dose Level 20g/24hNeurological Function Measured by the West Haven Criteria (WHC) for Hepatic Encephalopathy1.8 units on a scaleStandard Deviation 1.6

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026