Therapeutic Efficacy of L-Ornithine L-Aspartate Infusion in Patients With Acute Liver Failure
Recruitment status was Active, not recruiting
|First Received Date ICMJE||May 4, 2007|
|Last Updated Date||January 4, 2008|
|Start Date ICMJE||January 2005|
|Primary Completion Date||Not Provided|
|Current Primary Outcome Measures ICMJE
||Improvement in survival. [ Time Frame: Within 30 days of disease onset ]|
|Original Primary Outcome Measures ICMJE||Same as current|
|Change History||Complete list of historical versions of study NCT00470314 on ClinicalTrials.gov Archive Site|
|Current Secondary Outcome Measures ICMJE
|Original Secondary Outcome Measures ICMJE||Same as current|
|Current Other Outcome Measures ICMJE||Not Provided|
|Original Other Outcome Measures ICMJE||Not Provided|
|Brief Title ICMJE||Therapeutic Efficacy of L-Ornithine L-Aspartate Infusion in Patients With Acute Liver Failure|
|Official Title ICMJE||Therapeutic Efficacy of L-Ornithine L-Aspartate Infusion in Patients With Acute Liver Failure: A Double- Blind, Randomized, Placebo- Controlled Study|
The purpose of the study is to determine whether L-Ornithine L-Aspartate infusion improves the survival of patients with acute liver failure.
Acute liver failure (ALF) has a high mortality. However, those who survive recover completely without any sequel. Liver transplantation is logistically and financially difficult in most countries with the highest disease burden. It also entails a lifelong commitment to immunosuppression. We therefore need new treatment options to improve the survival of medically managed patients with ALF.
Ammonia is believed to be the major neurotoxin in ALF. There is experimental evidence of direct and indirect ammonia neurotoxicity in ALF. The brain does not have a urea cycle, and relies on glutamine synthesis in the astrocytes for removal of excess ammonia. Increased intracellular glutamine in the astrocytes leads to cellular swelling. Increased brain ammonia concentrations also result in altered expression of key astrocyte proteins including glial fibrillary acidic protein, glutamate and glycine transporters and "peripheral-type" (mitochondrial) BZD receptors. Accumulation of ammonia in brain results in a redistribution of cerebral blood flow from cortical to sub-cortical structures, and also has direct effects on neurotransmission. Increased ammonia concentration upregulates the peripheral-type benzodiazepine (PTBR) receptors in the outer membrane of astroglial mitochondria, and enhance the synthesis and release of neurosteroids, some of which are known GABA (A) receptor agonists.
There is now evidence of high blood ammonia levels in ALF , with a substantial blood-to-brain ammonia transfer.Brain-blood ammonia concentration ratios (normally of the order of 2) are increased up to 4 fold in liver failure. Higher ammonia levels have been co-related with higher mortality and complications in human clinical trials. Clemmesen et al found that ALF patients who died of cerebral herniation had higher ammonia levels as compared to the survivors. We have also previously shown that higher ammonia levels at admission predicts a poorer survival rate, and arterial ammonia levels are an independent predictor of mortality by logistic regression analysis. An arterial ammonia level of > 124 μmol/l was found to predict mortality with 78.6% sensitivity and 76.3% specificity.There is thus a strong rationale for using ammonia lowering therapies in ALF.
LOLA is a compound salt of Ornithine and Aspartate. The mechanism of its ammonia lowering action has been defined. LOLA provides critical substrates for both urea and glutamine synthesis- the key pathways of ammonia detoxification in the liver. Urea synthesis is carried out in a low affinity, high capacity system that exists largely in the periportal hepatocytes. In these cells, Ornithine serves as an activator of ornithine-carbamoyltransferase and carbamylphosphate-synthetase. In addition, Ornithine itself acts as a substrate for urea genesis. Hence LOLA can activate the periportal urea cycle. Glutamine synthesis is a high affinity, relatively low capacity system located in the perivenous hepatocytes. Ornithine is converted to α -ketoglutarate, and taken up by these perivenous hepatocytes and serves as a carbon source for glutamine synthesis. LOLA also upregulates glutamine synthesis in the skeletal muscle via glutamine synthetase (GS). Recently, in animal models an increased transport of ornithine across the blood brain barrier and an increase in the brain glutamine synthesis after LOLA treatment has been described, and suggests that LOLA may have both centrally (CNS) and peripherally mediated effects. , LOLA has been shown to reduce raised ammonia levels in experimental models of hyper-ammonemia, and in human cirrhotic patients. In patients with cirrhosis,LOLA improves psychometric performance and improves the mental status.
LOLA is therefore a promising agent for use in ALF patients. It has scientific rationale and has been found to be effective in cirrhosis. There is however only a single experimental study of LOLA in a rat model of acute liver injury. LOLA infusion could normalize the plasma ammonia and lead to a significant reduction in brain water content. We would like to study whether LOLA infusion in patients with ALF can reduce ammonia levels and improve survival.
|Study Type ICMJE||Interventional|
|Study Phase||Phase 2|
|Study Design ICMJE||Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Parallel Assignment
Primary Purpose: Treatment
|Condition ICMJE||Acute Liver Failure|
|Intervention ICMJE||Drug: L-Ornithine L-Aspartate|
|Study Arm (s)||Not Provided|
* Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
|Recruitment Status ICMJE||Active, not recruiting|
|Estimated Completion Date||May 2007|
|Primary Completion Date||Not Provided|
|Eligibility Criteria ICMJE||
|Accepts Healthy Volunteers||No|
|Contacts ICMJE||Contact information is only displayed when the study is recruiting subjects|
|Location Countries ICMJE||India|
|NCT Number ICMJE||NCT00470314|
|Other Study ID Numbers ICMJE||GE-LOLA/2005|
|Has Data Monitoring Committee||No|
|Responsible Party||Not Provided|
|Study Sponsor ICMJE||All India Institute of Medical Sciences, New Delhi|
|Collaborators ICMJE||Not Provided|
|Information Provided By||All India Institute of Medical Sciences, New Delhi|
|Verification Date||April 2007|
ICMJE Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP