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L-ornithine L-aspartate

Medical University of Graz · FDA-approved active Small molecule

L-ornithine L-aspartate enhances ammonia detoxification by promoting urea cycle function and glutamine synthesis in hepatic encephalopathy.

L-ornithine L-aspartate enhances ammonia detoxification by promoting urea cycle function and glutamine synthesis in hepatic encephalopathy. Used for Hepatic encephalopathy (acute and chronic), Portal-systemic encephalopathy.

At a glance

Generic nameL-ornithine L-aspartate
Also known asHepa-Merz, Hepamerz
SponsorMedical University of Graz
Drug classAmmonia-lowering agent
TargetUrea cycle enzymes (ornithine transcarbamylase, carbamoyl phosphate synthetase); glutamine synthetase
ModalitySmall molecule
Therapeutic areaHepatology / Gastroenterology
PhaseFDA-approved

Mechanism of action

The drug provides substrates (ornithine and aspartate) that stimulate the urea cycle and increase ammonia clearance through enhanced glutamine formation in muscle and liver. By reducing circulating ammonia levels, it alleviates the neurological symptoms associated with hepatic encephalopathy, particularly in patients with chronic liver disease or portal hypertension.

Approved indications

Common side effects

Key clinical trials

Primary sources

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SourceUsed for
ClinicalTrials.govTrial enrolment, design, endpoints, results

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