CirrhosisPhase 4LOLAbiomeNCT05737030
Effect of L-ornithine-L-aspertate (LOLA) on the Gut Microbiome
A Phase 4 study testing L-ornithine L-aspartate in people with Cirrhosis, run by Medical University of Graz at 1 site in Austria.
Trial summary
Study to test the effect of the drug "L-ornithine.L-aspertate" (LOLA) on microorganisms in the digestive tract in patients with liver cirrhosis (damage of the liver due to liver disease) Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Cirrhosis
- What is being tested?
- L-ornithine L-aspartate
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 52 participants
- Where
- 1 siteAustria
- Study dates
- 6 Feb 2023to 31 Dec 2025
- Phase
- Phase 4
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- • Liver cirrhosis (clinical/radiological/histological diagnosis)
- Indication for LOLA use (covert or over hepatic encephalopathy, Grad 0-2))
- Written informed consent
- Age 18 -100 years
Who cannot join
- • Allergy to LOLA or its constituents, or to medications with a similar chemical structure (oral nutritional supplements are allowed when stable >/= 8 weeks before and during the study)
- Recent (</= 8 weeks) changes of the dose of the lactulose therapy for hepatic encephalopathy
- Rifaximin or any other antibiotic therapy within the past 4 weeks
- Intake of LOLA in the past four weeks before inclusion
- Intake of L-dopamine
- Renal insufficiency with a serum creatinine >3mg/dl
Show all 10Show fewer
- Hepatocellular carcinoma BCLC D under best supportive care
- Inability to give informed consent
- Pregnancy or breastfeeding
- Participation in another interventional trial within the last 30 days
Trial locations and contacts
1 site in 1 country.
Austria1 site
Department of Internal Medicine, Medical University of Graz
Graz, 8010
About this study
Official title: An Observational Study on the Effect of L-ornithine-L-aspertate (LOLA) on the Flavonifractor Abundance in the Gut Microbiome in Liver Cirrhosis
Study to test the effect of the drug "L-ornithine.L-aspertate" (LOLA) on microorganisms in the digestive tract in patients with liver cirrhosis (damage of the liver due to liver disease)
Read the detailed description
Liver cirrhosis is associated with gut microbiome dysbiosis, which may drive intestinal inflammation, gut barrier dysfunction and the development of complications. LOLA is a well-established drug against elevated ammonia levels that contribute to hepatic encephalopathy and sarcopenia. In a recent retrospective study, LOLA has been shown to improve gut microbiome dysbiosis.
In this study we aim to investigate whether LOLA therapy over three months in patients with liver cirrhosis (irrespective of the etiology) and covert or overt hepatic encephalopathy (HE) leads to an improvement in gut microbiome dysbiosis, as well as markers of gut permeability, inflammation, muscle function and ammonia levels.
- Conditions
- Cirrhosis
- Being tested
- L-ornithine L-aspartate
- Medical subject headings
- Fibrosis
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
L-ornithine L-aspartateDrug
Also called Hepa-Merz
Amino acid combination
| Study group | Role | What they receive |
|---|---|---|
| L-ornithine-L-aspertate | Experimental | L-ornithine-L-aspertate 18g per day Receives: Drug: L-ornithine L-aspartate |
What is being measured
The primary outcome is the main question the study is designed to answer.
Microbiome
Increase of the genus Flavonifractor in the gut microbiome after 3 months of LOLA treatment
Measured: 3 months
Secondary outcomes (11)
Alpha diversity
Change in alpha diversity of the gut microbiome after 3 months of LOLA treatment
Measured: 3 months
Beta diversity
Change in beta diversity of the gut microbiome after 3 months of LOLA treatment
Measured: 3 months
Taxonomic composition
Change in taxonomic composition (beyond Flavonifractor) of the gut microbiome after 3 months of LOLA treatment
Measured: 3 months
Predicted metagenomics
Change in predicted gut microbiome function after 3 months of LOLA treatment
Measured: 3 months
Metabolomics
Change in stool, serum or urine metabolite composition after 3 months of LOLA treatment
Measured: 3 months
Gut permeability
Change in biomarkers of gut permeability (zonulin, DAO, sCD14, LBP) after 3 months of LOLA treatment
Measured: 3 months
Handgrip strength
Change in handgrip strength after 3 months of LOLA treatment
Measured: 3 months
Muscle function
Change in gait speed and balance after 3 months of LOLA treatment
Measured: 3 months
Ammonia in serum
Change in ammonia blood levels after 3 months of LOLA treatment
Measured: 3 months
Mid-arm circumference and triceps fold thickness
Change in anthropometric parameters (Mid-arm circumference and triceps fold thickness) after 3 months of LOLA treatment
Measured: 3 months
short form (SF)-36
Change in quality of life after 3 months of LOLA treatment, 8 domains, 0-100 points, higher points indicate higher quality of life
Measured: 3 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted21 Feb 2023
- Study start6 Feb 2023
- Primary completion23 Jul 2024
- Study completion31 Dec 2025
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for CirrhosisStudies of the same condition, open and under way.
- More trials run by Medical University of GrazThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 4
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 52 participants (actual)
Sponsor and investigators
- Lead sponsor
- Medical University of Graz
- Sponsor type
- University, hospital or other
- Collaborators
- CBmed Ges.m.b.H.
- Responsible party
- Principal investigator, Vanessa Stadlbauer-Koellner, MD, Medical University of Graz
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05737030
- Sponsor's protocol ID
- LOLAbiome
- Other IDs
- 2022-002924-11
- Acronym
- LOLAbiome
- Status last verified
- Oct 2026
- First submitted
- 12 Feb 2023
- Last updated
- 9 Oct 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: Sequencing data will be deposited in an open access repository together with metadata
Publications
Habich D, Horvath A, Feldbacher N, Rebol L, Nepel M, Madl T, Habisch HJ, Baumann-Durchschein F, Furst S, Plank J, Rainer F, Spindelbock W, Stauber RE, Tatscher E, Wagner M, Zollner G, Stadlbauer V. An observational study on the effect of l-ornithine-l-aspartate (LOLA) on the gut microbiome in liver cirrhosis. A single center phase 4 study. Clin Nutr. 2026 Jan;56:106522. doi: 10.1016/j.clnu.2025.11.007. Epub 2025 Nov 29.
PubMed 41406626
Study at a glance
From the registry record, last updated by the sponsor on 9 Oct 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- An Observational Study on the Effect of L-ornithine-L-aspertate (LOLA) on the Flavonifractor Abundance in the Gut Microbiome in Liver Cirrhosis
- ClinicalTrials.gov ID
- NCT05737030
- Acronym / sponsor ID
- LOLAbiome / LOLAbiome
- Conditions
- Cirrhosis
- Phase
- Phase 4
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 52 participants (actual)
- Lead sponsor
- Medical University of GrazUniversity, hospital or other
- Collaborators
- CBmed Ges.m.b.H.
- Study start
- 6 Feb 2023 (actual)
- Primary completion
- 23 Jul 2024 (actual)
- Study completion
- 31 Dec 2025 (actual)
- First posted
- 21 Feb 2023 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Study to test the effect of the drug "L-ornithine.L-aspertate" (LOLA) on microorganisms in the digestive tract in patients with liver cirrhosis (damage of the liver due to liver disease)
Detailed description
Liver cirrhosis is associated with gut microbiome dysbiosis, which may drive intestinal inflammation, gut barrier dysfunction and the development of complications. LOLA is a well-established drug against elevated ammonia levels that contribute to hepatic encephalopathy and sarcopenia. In a recent retrospective study, LOLA has been shown to improve gut microbiome dysbiosis.
In this study we aim to investigate whether LOLA therapy over three months in patients with liver cirrhosis (irrespective of the etiology) and covert or overt hepatic encephalopathy (HE) leads to an improvement in gut microbiome dysbiosis, as well as markers of gut permeability, inflammation, muscle function and ammonia levels.
Study design
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| L-ornithine-L-aspertate | Experimental | Drug: L-ornithine L-aspartateL-ornithine-L-aspertate 18g per day |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (4 listed)
- • Liver cirrhosis (clinical/radiological/histological diagnosis)
Key exclusion criteria (10 listed)
- • Allergy to LOLA or its constituents, or to medications with a similar chemical structure (oral nutritional supplements are allowed when stable >/= 8 weeks before and during the study)
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| L-ornithine L-aspartateAlso: Hepa-MerzAmino acid combination | Drug | L-ornithine-L-aspertate |
Primary outcome
Microbiome
Time frame: 3 months
Increase of the genus Flavonifractor in the gut microbiome after 3 months of LOLA treatment
11 secondary outcomes
Alpha diversity
Time frame: 3 months
Beta diversity
Time frame: 3 months
Taxonomic composition
Time frame: 3 months
Predicted metagenomics
Time frame: 3 months
Metabolomics
Time frame: 3 months
Gut permeability
Time frame: 3 months
Handgrip strength
Time frame: 3 months
Muscle function
Time frame: 3 months
Ammonia in serum
Time frame: 3 months
Mid-arm circumference and triceps fold thickness
Time frame: 3 months
short form (SF)-36
Time frame: 3 months
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 9 Oct 2026.
- Derived from this study: PubMed 41406626Habich D, Horvath A, Feldbacher N, Rebol L, Nepel M, Madl T, Habisch HJ, Baumann-Durchschein F, Furst S, Plank J, Rainer F, Spindelbock W, Stauber RE, Tatscher E, Wagner M, Zollner G, Stadlbauer V. An observational study on the effect of l-ornithine-l-aspartate (LOLA) on the gut microbiome in liver cirrhosis. A single center phase 4 study. Clin Nutr. 2026 Jan;56:106522. doi: 10.1016/j.clnu.2025.11.007. Epub 2025 Nov 29.
- Individual participant dataSharing planned: Yes. Sequencing data will be deposited in an open access repository together with metadata
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 4 study testing L-ornithine L-aspartate in people with Cirrhosis, run by Medical University of Graz at 1 site in Austria.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 10 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 9 Oct 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Austria. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 4 studies take place after a treatment is approved, to learn more about its long-term benefits and risks in everyday use.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Microbiome (time frame: 3 months). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT05737030, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 9 Oct 2026.