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13C-Methacetin Breath Test for the Prediction of Outcome in in ALI or ALF

13C-Methacetin Breath Test for the Prediction of Outcome in in Acute Liver Injury or Acute Liver Failure

Status
Completed
Phases
Phase 2Phase 3
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT02786836
Acronym
ALFSG-MBT
Enrollment
76
Registered
2016-06-01
Start date
2016-06-10
Completion date
2019-09-18
Last updated
2020-12-22

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

Conditions

Acute Liver Failure

Keywords

acute liver failure, methacetin, breath test, severe acute liver injury, hepatic encephalopathy, ALFSG Registry, acetaminophen toxicity

Brief summary

The ALFSG-MBT protocol is for a multicenter, open label, non-randomized study to determine the value of Breath Identification® (BreathID®) N-(4-Methoxy-13C-phenyl)acetamide (13C-Methacetin) Breath Test System in predicting the outcome of patients diagnosed with severe acute liver injury that is not related to acetaminophen overdose or acute liver failure who meet inclusion/exclusion criteria. Up to 200 evaluable patients will be enrolled. An evaluable patient is one who has completed one or more breath tests for at least 30 minutes after administration of the 13C-Methacetin solution (test substrate). The Breath Test will be performed up to five times during the study period on all enrolled patients. The first Breath Test will be performed upon admission into the study (Day 1) and repeated on Days 2, 3, 5 and 7 provided no contra-indications are present. Each test continuously measures changes in the metabolism of the 13C-Methacetin in order to assess the improvement or deterioration in liver metabolic function about improvement or deterioration in liver metabolic function. If an enrolled non-APAP ALI or ALF patient receives a liver transplant, is discharged /transferred from the hospital or dies prior to Day 7, additional Breath Tests will not be performed. Patients will be contacted for the Day 21 follow up (21 days after enrollment into the trial) to determine spontaneous survival, transplantation and occurrence of serious adverse events since the patient's last study treatment.

Detailed description

The importance of identifying the patient with with ALI or ALF who is likely to die without a liver transplant cannot be overstated and has remained a primary focus of clinical investigation for 25 years. A recent analysis also conducted by the Acute Liver Failure Study Group (ALFSG) found that poor outcomes in the ALI patients are less frequent than is observed in the ALF population. However, in cases where ALI was not related to an acetaminophen (APAP) overdose, progression to poor outcomes was similar. Traditional scoring systems and prognostic models, such as King's College Criteria (KCC), Sequential Organ Failure Assessment (SOFA) and Acute Physiology and Chronic Health Evaluation II (APACHE II), currently used to monitor patients with ALF lack individual sensitivity and specificity and do not provide direct information about the liver's metabolic function, which is a key variable in assessing liver status and potential disease progression versus recovery in ALF patients. Despite recent advances used by the ALFSG Prognostic Index (ALFSG-PI), ALI Prognostic Index (ALI-PI) and Model for End-Stage Liver Disease (MELD), better predictive modalities are still needed. The 13C-Methacetin breath test is a rapid, reproducible, point-of-care test of liver metabolic function. After oral or naso-enteric/orogastric tube administration, the 13C labeled Methacetin is O-demethylated by cytochrome P450 1A2 (liver enzyme name) in the liver and further biotransformed into carbon dioxide labeled with carbon 13 (13CO2), which is expired in breath. The BreathID® Molecular Correlation Spectroscopy (MCS) device captures and quantifies expired 13CO2 and standardizes recovery against expired normal carbon dioxide (12CO2) through a nasal cannula (in conscious patients) or an adaptor connected to the ventilator line (for intubated patients). The results obtained from the device are expressed as delta over baseline (DOB), which expresses the change in 13CO2/12CO2 ratio in comparison to the baseline measurement. It can be transformed into the percentage of 13C dose recovered over time (PDR) after the ingestion of Methacetin, and the cumulative PDR (CPDR), the rate at which 13C substrate is metabolized, derived from the breath 13C/12C ratio. This is a multicenter, open label, non-randomized study of the MBT to assess functional trends of liver metabolism in patients diagnosed with severe acute liver injury not related to acetaminophen overdose (non-APAP ALI) or acute liver failure (ALF). Up to 200 evaluable patients with non-APAP ALI or ALF present at the time of enrollment into the ALFSG Registry will be consecutively enrolled. An evaluable patient is one who has completed one or more Breath Tests measured for a minimum of 30 (and ideally 60) minutes after administration of the 13C-Methacetin solution. Study sites will include up to 11 of the clinical sites located in the United States that are involved in the ALFSG. The Breath Test will be performed up to five times during the study period on all enrolled subjects. The first Breath Test will be performed as close to the time of study enrollment as possible upon admission into the study (Day 1). The Breath Test will be repeated on Days 2, 3, 5 and 7 as close as possible to the same time of day as the first Breath Test. If a subject who is enrolled into the ALFSG-MBT Trial with non-APAP ALI converts to ALF, breath test collection will continue until a maximum of five Breath Tests have been performed. If an enrolled non-APAP ALI or ALF subject receives a liver transplant, is discharged/transferred from the hospital or dies prior to Day 7, no additional Breath Tests will be performed. Enrolled patients will be contacted for the Day 21 follow up (21 days after the subject's enrollment into the trial) to determine spontaneous survival, transplantation and occurrence of serious adverse events since the subject's last study treatment.

Interventions

The test substrate in this study, ¹³C-methacetin solution for single-use oral administration (75 mg in 150 ml purified water), is administered orally or via feeding tube, rapidly absorbed, exclusively metabolized by hepatic mixed function oxidase via O-demethylation, mainly by cytochrome P450 enzyme, subtype 1A2, into acetaminophen and formaldehyde. The formaldehyde is then transformed through two successive oxidative steps to ¹³carbon dioxide, the quantity of which is measured in exhaled breath as a ratio of 13C to 12C. The nasal or intubated breath sampling investigational device (ID) circuit continuously transports the breath sample from the patient to the BreathID® MCS device before and following administration of the 13C-methylacetanilide test substrate.

Sponsors

Medical University of South Carolina
CollaboratorOTHER
University of Michigan
CollaboratorOTHER
Meridian Bioscience, Inc.
CollaboratorINDUSTRY
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
CollaboratorNIH
University of Texas Southwestern Medical Center
Lead SponsorOTHER

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
DIAGNOSTIC
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to 80 Years
Healthy volunteers
No

Inclusion criteria

1. Adult men or women (18-80 years of age) 2. Severe acute liver injury not related to acetaminophen overdose: INR ≥2.0; no evidence of HE 3. Acute liver failure: INR ≥1.5; presence of any degree of HE 4. Duration of illness \<26 weeks 5. Enrolled into the ALFSG Registry. 6. Written informed consent from the patient or patient's legally authorized representative or family member as defined in the Federal Register Number 21 Congressional Federal Register (CFR)50.3(m)

Exclusion criteria

1. Evidence of pre-existing chronic liver disease 2. Pre-existing New York Heart Association stage III/IV heart failure 3. Evidence of pre-existing chronic renal failure 4. Chronic hemodialysis prior to hospital admission 5. Evidence of cirrhosis (unless clinically acute Wilson disease or autoimmune non-APAP ALI or ALF) 6. Severe obstructive lung disease (FEV1 \<50% of predicted on previous spirometry) 7. Severe shock, defined as mean arterial pressure (MAP) \<70 mmHg despite \>15 µg/kg/min dopamine, \>0.1 µg/kg/min epinephrine, or \>0.1 norepinephrine µg/kg/min 8. Extensive small bowel resection (\>50 cm) 9. Any evidence of upper GI bleeding at enrollment requiring intervention (endoscopy or red blood cell (RBC) transfusion specifically for upper GI bleeding) 10. Liver transplantation (LT) prior to enrollment. (Note: Listing for LT does not preclude participation in the trial.) 11. Pregnancy or breastfeeding women (Note: Pregnancy related non-APAP ALI or ALF may be considered for entry following the delivery of the baby and assuming the mother does not wish to breastfeed or collect breast milk during the study period.) 12. Allergic to acetaminophen (such as Tylenol® or any other acetaminophen-containing medications) 13. Participation in other clinical studies evaluating other experimental treatments or procedures. (Note: Participation in observatory studies is not an exclusion.) 14. Patients in whom enteral drugs or fluids are contra-indicated or the patient either does not have an appropriately placed naso-enteric/orogastric tube in situ or cannot tolerate taking the drug preparation orally (200 ml) 15. Budd-Chiari Syndrome 16. Non-APAP ALI or ALF caused by malignancy 17. Moderate and severe adult respiratory distress syndrome (ARDS), as defined by Berlin Criteria. 18. Subjects who have received amiodarone in the 30 days prior to study enrollment 19. Consumption of any food or beverage that contains caffeine in the 24 hours prior to enrollment 20. Consumption of any of the following drugs that may interfere with the metabolism of 13C-Methacetin in the 48 hours prior to study enrollment including: allopurinol, carbamazepine, cimetidine, ciprofloxacin, daidzein, disulfiram, Echinacea, enoxacin, fluvoxamine, methoxsalen, mexiletine, montelukast, norfloxacin, phenylpropanolamine, phenytoin, propafenone, rifampin, terbinafine, ticlopidine, thiabendazole, verapamil, zileuton or oral contraceptives 21. Consumption of alcohol in the 24 hours prior to enrollment 22. Smoking cigarettes in the 8 hours prior to enrollment.

Design outcomes

Primary

MeasureTime frameDescription
Peak Percent Dose Recovery (PDR) ValueDays 1 and 21Peak PDR is the maximal percent dose recovery (PDR) rate which reflects the maximum rate of metabolism of 13C-methacetin measured as the change in 13CO2 / 12CO2 (normal carbon dioxide) ratio after ingestion of 13C-methacetin normalized using the patient's height and weight. The distributions of mean PDR Peak values were compared between TFS (transplant free survival) and non-TFS (death/transplant) at Day 21.

Secondary

MeasureTime frameDescription
Peak Percent Dose Recovery (PDR) ValueThe first MBT reading either on Day 1 or Day 2 and Day 21This outcome is similar to the peak PDR defined in the primary outcome but as a secondary we are looking at Day 1 or Day 2 peak PDR values. Peak PDR is the maximal percent dose recovery (PDR) rate which reflects the maximum rate of metabolism of 13C-methacetin measured as the change in 13CO2 / 12CO2 ratio after ingestion of 13C-methacetin normalized using the patient's height and weight. The distributions of mean PDR Peak values were compared between TFS and non-TFS (death/transplant) at Day 21.
Cumulative Percent Dose Recovery 20 (cPDR20) ValueThe first MBT reading either on Day 1 or Day 2 and Day 21The relationship between the cPDR (cumulative PDR of metabolized 13C-Methacetin 20 minutes after ingestion) in single time points of MBT measurements and TFS and non-TFS (death/transplant) at Day 21.

Countries

United States

Participant flow

Recruitment details

Patients with acute liver failure (ALF) who were enrolled into the ALF Study Group Registry at 11 participating investigative U.S. sites were screened for eligibility. In March 2018, patients with acute liver injury (ALI) not related to acetaminophen overdose (APAP) and enrolled into the ALFSG Registry were included and screened for eligibility.

Participants by arm

ArmCount
13C-Methacetin Breath Test (MBT)
For each MBT, a baseline measurement was taken for up to 15 minutes using a nasal cannula retrieval device for non-intubated patients or an airway adapter connection to the endotracheal tube of intubated patients that was connected to the Breath ID® MCS device. After completion of the baseline segment, one 75 mg dose of 13C-Methacetin (test substrate) mixed into 150 ml of water was orally ingested by non-intubated patients or administered via nasoenteric tube to intubated patients. The BreathID® MCS device measured expired 13CO2 over a period of up to 60 minutes. A maximum of 5 daily tests were administered on study days 1, 2, 3, 5 and 7 for up to 1 hour after test substrate administration. Patients were contacted 21 days following study enrollment to determine vital status and to check for the development of serious adverse events.
62
Total62

Withdrawals & dropouts

PeriodReasonFG000
Overall StudyDeath1
Overall StudyDevice or Pharmacy Issues3
Overall StudyLack of Efficacy2
Overall StudyLiver Transplantation2
Overall StudyProtocol Violation3
Overall StudyWithdrawal by Subject3

Baseline characteristics

Characteristic13C-Methacetin Breath Test (MBT)
Age, Continuous43 years
Day 1 MBT measured for a minimum of 30 minutes after ingestion of the 13C-Methacetin solution56 Participants
Race/Ethnicity, Customized
Asian
2 Participants
Race/Ethnicity, Customized
Black
11 Participants
Race/Ethnicity, Customized
Hispanic
4 Participants
Race/Ethnicity, Customized
White
49 Participants
Sex: Female, Male
Female
24 Participants
Sex: Female, Male
Male
38 Participants

Adverse events

Event typeEG000
affected / at risk
deaths
Total, all-cause mortality
11 / 62
other
Total, other adverse events
40 / 62
serious
Total, serious adverse events
28 / 62

Outcome results

Primary

Peak Percent Dose Recovery (PDR) Value

Peak PDR is the maximal percent dose recovery (PDR) rate which reflects the maximum rate of metabolism of 13C-methacetin measured as the change in 13CO2 / 12CO2 (normal carbon dioxide) ratio after ingestion of 13C-methacetin normalized using the patient's height and weight. The distributions of mean PDR Peak values were compared between TFS (transplant free survival) and non-TFS (death/transplant) at Day 21.

Time frame: Days 1 and 21

Population: Eligible patients enrolled into the study with available Day 1 13C-MBT results and 21-day outcome.

ArmMeasureGroupValue (MEAN)Dispersion
13C-Methacetin Breath Test (MBT)Peak Percent Dose Recovery (PDR) ValueMean Peak PDR for TFS subjects at Day 2110.2 percentage per hourStandard Deviation 7.8
13C-Methacetin Breath Test (MBT)Peak Percent Dose Recovery (PDR) ValueMean Peak PDR for non-TFS subjects at Day 211.9 percentage per hourStandard Deviation 0.6
Secondary

Cumulative Percent Dose Recovery 20 (cPDR20) Value

The relationship between the cPDR (cumulative PDR of metabolized 13C-Methacetin 20 minutes after ingestion) in single time points of MBT measurements and TFS and non-TFS (death/transplant) at Day 21.

Time frame: The first MBT reading either on Day 1 or Day 2 and Day 21

Population: Eligible patients enrolled into the study with the initial 13C-MBT conducted on Day 1 or Day 2, and 21 day outcome.

ArmMeasureGroupValue (MEAN)Dispersion
13C-Methacetin Breath Test (MBT)Cumulative Percent Dose Recovery 20 (cPDR20) ValueDay 1 or 2 MBT/transplant free survival at Day 211.4 percentage per hourStandard Deviation 1.3
13C-Methacetin Breath Test (MBT)Cumulative Percent Dose Recovery 20 (cPDR20) ValueDay 1 or 2 MBT & Day 21 non-TFS0.2 percentage per hourStandard Deviation 0.2
Secondary

Peak Percent Dose Recovery (PDR) Value

This outcome is similar to the peak PDR defined in the primary outcome but as a secondary we are looking at Day 1 or Day 2 peak PDR values. Peak PDR is the maximal percent dose recovery (PDR) rate which reflects the maximum rate of metabolism of 13C-methacetin measured as the change in 13CO2 / 12CO2 ratio after ingestion of 13C-methacetin normalized using the patient's height and weight. The distributions of mean PDR Peak values were compared between TFS and non-TFS (death/transplant) at Day 21.

Time frame: The first MBT reading either on Day 1 or Day 2 and Day 21

Population: Eligible patients enrolled into the study with available Day 1 or Day 2 13C-MBT results and 21-day outcome.

ArmMeasureGroupValue (MEAN)Dispersion
13C-Methacetin Breath Test (MBT)Peak Percent Dose Recovery (PDR) ValueDay 1 or 2 MBT & Day 21 TFS9.1 percentage per hourStandard Deviation 6.8
13C-Methacetin Breath Test (MBT)Peak Percent Dose Recovery (PDR) ValueDay 1 or 2 MBT & Day 21 non-TFS2.3 percentage per hourStandard Deviation 0.9

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