This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for Pharmacokinetic and Pharmacodynamic Study of IDN-6556 in ACLF (NCT01937130), a randomized phase 2 study. The primary outcome is Area Under the Curve (AUC).
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01937130 |
| Phase | Phase 2 |
| Condition | Acute on Chronic Hepatic Failure, Acute Liver Failure, Liver Cirrhosis |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Triple |
| Enrollment | 23 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Conatus Pharmaceuticals Inc. |
| Results posted | Yes |
2. Clinical Question
Population
The study concerned subjects with cirrhosis who were hospitalized for more than 24 hours because of acute deterioration of liver function. The listed conditions also include acute on chronic hepatic failure, acute liver failure, liver cirrhosis, and acute alcoholic hepatitis. The registry record does not report further eligibility details or how these conditions were represented among enrolled participants.
Intervention
Participants were assigned to IDN-6556 at 5 mg, 25 mg, or 50 mg, with each dose described as twice daily. The study aimed to evaluate pharmacokinetics, pharmacodynamics, safety, and preliminary efficacy. The registry record does not state the treatment duration for each participant.
Comparator
The comparator was placebo, also described as dosed twice daily. The study is identified as randomized, placebo-controlled, and parallel-group. The registry record does not provide a comparative estimate for any outcome.
Primary question
The primary endpoints concerned IDN-6556 exposure, measured as area under the concentration-time curve for AUC 0-8, AUC 0-last, and AUC 0-inf on Day 1 and Day 4 in active-treatment arms. The stated primary-outcome timeframe is 28 days. The record describes these endpoints as analyzed, but gives no corresponding endpoint values, uncertainty estimates, or treatment comparisons.
In statistical terms, the central question was how drug exposure varied across the active dose groups and measurement occasions. The registry record also lists pharmacodynamic measures—CK18/M30, CK18/M65, and Caspase 3/7 RLU—as secondary outcomes, alongside safety and preliminary efficacy in the study summary. The available record does not establish whether these secondary measures were analyzed or what their results were. The study status is terminated, but the reason for termination is not reported in the registry record.
3. Trial Design
This was a Phase 2 randomized, parallel-group study comparing IDN-6556 with placebo. The registry record identifies four arms: IDN-6556 5 mg, IDN-6556 25 mg, IDN-6556 50 mg, and placebo. All are described as dosed twice daily. The trial is characterized as multicenter and placebo-controlled in its official title. Its masking field says triple, while the official title describes the study as double-blind. The record does not explain the masking procedures or how these descriptions relate.
The enrollment figure is 23. That is the registry’s enrollment value, not a statement of how many participants were analyzed for every endpoint. The available primary-outcome population text gives selected analysis counts, and those counts vary by dose, endpoint, and measurement day. The record does not provide a complete account of participant flow, arm-level enrollment, withdrawals, or exclusions.
The study started in 2013-09, had a primary completion date of 2015-01, and is listed as terminated. These dates and status do not explain why the study ended or whether termination affected follow-up or analysis. The reason is not reported in the registry record.
The planned assessment was pharmacokinetic and pharmacodynamic, with safety and preliminary efficacy also named in the study summary. For the primary outcome, the registry lists AUC 0-8, AUC 0-last, and AUC 0-inf on Day 1 and Day 4 for active-treatment arms, with a stated timeframe of 28 days. The record does not describe the timing of other outcome assessments, the planned contrasts, or which dose comparisons were intended to support a formal conclusion. It also does not report a protocol-level statistical analysis plan.
Randomization can help balance measured and unmeasured participant characteristics across groups on average, while masking can limit some forms of bias in treatment delivery and assessment. These are general design considerations; the registry record does not specify the randomization method, allocation concealment, or the practical masking procedures. Without those details and a reported comparative analysis, the design description alone cannot establish the size or precision of any treatment difference.
4. Participant Flow and Accounting
The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.
Before assignment: 23 subjects were randomized but 21 subjects received treatment. 1 subject lost due to death and 1 subject lost due to withdrew of consent. 7 subject of 21 completed the treatment phase (Day 28). 4 of 3 completed the two follow-up phone calls made at Months 3 and 6. 14 subjects discontinued the study early.
Overall Study
| Stage | IDN-6556 5 mg | IDN-6556 25 mg | IDN-6556 50 mg | Placebo |
|---|---|---|---|---|
| STARTED | 5 | 7 | 5 | 4 |
| COMPLETED | 0 | 3 | 2 | 2 |
| NOT COMPLETED | 5 | 4 | 3 | 2 |
Reasons for not completing this period:
| Reason | IDN-6556 5 mg | IDN-6556 25 mg | IDN-6556 50 mg | Placebo |
|---|---|---|---|---|
| Withdrawal by Subject | 0 | 0 | 0 | 1 |
| Adverse Event | 0 | 1 | 0 | 1 |
| Death | 1 | 1 | 1 | 0 |
| Lost to Follow-up | 2 | 0 | 2 | 0 |
| Physician Decision | 0 | 1 | 0 | 0 |
| Patients unable to swallow | 0 | 1 | 0 | 0 |
| Patient lost to FU due to death | 2 | 0 | 0 | 0 |
Analysis population for the primary outcome, as defined in the registry: AUC\_0-last: The number of participants analyzed in the 25mg arm was 7 at Day 1 AUC\_0-inf: The number of participants analyzed in the 5mg arm was 2 at Day 1 and 0 at Day 4, in the 25mg arm was 5 at Day 1 and 2 at Day 4, in the 50mg arm was 2 at Day 1 and 3 at Day 4. Values listed as "0" were non-estimable values.
5. Baseline Characteristics
The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.
Population: Subjects with acute-on-Chronic liver failure (ACLF)
| Characteristic | Unit | IDN-6556 5 mg | IDN-6556 25 mg | IDN-6556 50 mg | Placebo | Total |
|---|---|---|---|---|---|---|
| Participants analysed | 5 | 7 | 5 | 4 | 21 | |
| Age, Categorical: <=18 years | Participants | 0 | 0 | 0 | 0 | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 5 | 7 | 4 | 4 | 20 |
| Age, Categorical: >=65 years | Participants | 0 | 0 | 1 | 0 | 1 |
| Age, Continuous | years | 49.0 (41 to 60) | 50.0 (30 to 58) | 61.0 (42 to 71) | 53.5 (34 to 59) | 50.0 (30 to 71) |
| Sex: Female, Male: Female | Participants | 2 | 2 | 2 | 2 | 8 |
| Sex: Female, Male: Male | Participants | 3 | 5 | 3 | 2 | 13 |
| Region of Enrollment: United States | participants | 0 | 2 | 1 | 2 | 5 |
| Region of Enrollment: United Kingdom | participants | 5 | 5 | 4 | 2 | 16 |
6. Primary Endpoint
The registry lists the primary outcome as Area Under the Curve (AUC), measured over 28 days.
| Element | Registry entry |
|---|---|
| Result type | Geometric Mean |
| Measure of spread | Geometric Coefficient of Variation |
| Unit | h*ng/mL |
| Endpoint classification | not reduced to a single comparison |
The primary outcome is area under the curve (AUC), reported in h*ng/mL. AUC is a measure of drug exposure over a specified span of time: conceptually, it summarizes concentration across the period being assessed. The registry lists AUC 0-8, AUC 0-last, and AUC 0-inf for Day 1 and Day 4 in the active-treatment arms. These definitions cover a fixed initial interval, an interval ending at the last observed concentration, and an extrapolated interval to infinity, respectively; this is a general explanation of the endpoint terminology.
Pharmacokinetic AUC is used to characterize exposure rather than to directly measure a clinical benefit. Comparing exposure across doses or occasions can help describe how much drug reaches the circulation over time. The registry specifies geometric means as the summary measure and geometric coefficient of variation as the dispersion measure. Geometric summaries are often used for positive measurements that vary multiplicatively; the coefficient of variation describes relative variability on a geometric scale. This is general statistical context, not a claim about the observed distribution in this study.
The stated timeframe is 28 days, while the endpoint description names Day 1 and Day 4. The record does not explain the relation between that timeframe and the listed measurements. It gives no AUC values or geometric coefficients of variation, so the magnitude and precision of exposure cannot be assessed from the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record describes the endpoint and selected analysis-population counts, but it does not present the primary AUC results. In particular, no geometric mean values, geometric coefficients of variation, confidence intervals, or formal comparisons are reported. There is therefore no numerical basis in the record for describing the size, direction, or precision of differences in exposure across doses or measurement days.
The population text states that AUC 0-last was analyzed in 7 participants in the 25mg arm at Day 1. For AUC 0-inf, it reports 2 participants in the 5mg arm at Day 1 and 0 at Day 4; 5 participants in the 25mg arm at Day 1 and 2 at Day 4; and 2 participants in the 50mg arm at Day 1 and 3 at Day 4. The record does not provide corresponding counts for every listed endpoint, including AUC 0-8, and does not explain all analysis-population differences. A count of 0 for a particular endpoint and occasion indicates that no participant was listed as analyzed in that cell; it does not supply an exposure estimate.
The registry reports an enrollment value of 23, but that value should not be treated as the denominator for each endpoint. Endpoint-specific analysis counts can differ from overall enrollment because not every participant necessarily contributes usable measurements to every analysis. Reasons for any such differences are not reported in the registry record. The available details are insufficient to assess whether missing measurements could have influenced the endpoint summaries.
The adverse-event information is descriptive. For serious adverse events, the listed at-risk and affected counts are 5 and 3 for IDN-6556 5 mg, 7 and 6 for IDN-6556 25 mg, 5 and 3 for IDN-6556 50 mg, and 4 and 2 for placebo. Those counts do not constitute a statistical comparison. The record does not provide inferential estimates, uncertainty intervals, or a stated method for comparing safety across groups. Death counts are null, which means they are not reported in the registry record; it does not establish that no deaths occurred.
Overall, the posted information allows a reader to identify the endpoint definitions, some analysis counts, and the reported serious-event counts. It does not allow a reader to judge the primary exposure findings, statistical significance, or the precision of a treatment contrast. The study’s terminated status does not itself explain the absence of results or the reason for termination.
9. Statistical Methods Explained
What does the AUC summary describe?
Area under the curve is a way to summarize concentration over time. In pharmacokinetic work, the concentration-time curve describes measured drug concentration at different times after dosing, and its area represents cumulative exposure across the defined interval. AUC 0-8, AUC 0-last, and AUC 0-inf refer to different interval endpoints. As a general interpretation, a larger AUC indicates greater measured exposure over the relevant interval, but the registry record contains no AUC values with which to characterize exposure in this study.
The registry specifies a geometric mean and geometric coefficient of variation. A geometric mean is a summary that suits positive measurements that are naturally compared by proportional rather than additive changes. A geometric coefficient of variation describes relative spread on a geometric scale. These summaries can be informative when measurements are skewed, but the registry does not report the underlying data or enough detail to verify the distributional assumptions or the calculation method.
What can be inferred from the analysis counts?
Analysis counts identify how many participants contributed to particular endpoint summaries. The available text lists selected counts for AUC 0-last and AUC 0-inf by dose and day. Those counts are not complete for every endpoint and do not explain why participants were absent from a particular analysis. They are also not substitutes for the endpoint estimates: a count alone says nothing about the observed AUC values or their variability.
When analysis counts differ between outcomes or occasions, interpretation depends on why they differ and how missing measurements were handled. For example, a measurement might be unavailable, not collected, or excluded under a prespecified rule; the record does not state which circumstances applied. No imputation method, sensitivity analysis, or definition of the analysis population is reported in the registry record. As general statistical context, missingness can affect both the precision and potential bias of an estimate, depending on its causes and the analysis approach.
Why does study design matter?
Randomization is intended to make treatment groups comparable on average, limiting systematic differences at assignment. A parallel-group design assigns participants to a group and compares outcomes across groups rather than having each participant receive every assigned treatment in a crossover sequence. Placebo provides a comparison condition for the active treatment arms. Masking can reduce the influence of knowledge of assignment on care, reporting, or assessment. These are general principles. The registry record does not describe the randomization procedure, allocation concealment, implementation of triple masking, or whether anyone was unmasked.
Even with randomized assignment, a treatment comparison requires outcome estimates and a stated analysis method. The registry record does not include a primary endpoint contrast, confidence interval, or test result. It also does not identify whether the analysis adjusted for baseline values or other covariates. Such methods should not be assumed from the trial design alone.
What would a confidence interval contribute?
A confidence interval is a general statistical tool for expressing uncertainty around an estimate. Its width reflects precision under the assumptions of the analysis; a wider interval indicates less precise estimation than a narrower interval. For a comparative estimate, an interval also helps show which effect sizes remain compatible with the data under the method used. No confidence intervals are reported for the primary outcome in this registry record, so precision cannot be described numerically.
A significance test, if reported, would address compatibility of data with a specified null hypothesis under its assumptions. It would not by itself show whether an effect is large, important, or precisely estimated. No p-value or formal primary endpoint test is listed. The registry marks the analysis count as 0, and it does not state whether an analysis was conducted but not entered or whether results were unavailable for another reason.
What does variability mean for these measurements?
Pharmacokinetic measurements can vary between participants and across sampling occasions. A measure of dispersion helps distinguish a typical value from the spread around it. Geometric coefficient of variation is the stated dispersion statistic. General considerations such as assay variability, timing of samples, and participant-level variation can matter for exposure measurements, but the registry record does not provide assay details, sampling schedules beyond the named days and intervals, or individual measurements. No cause of variation should be inferred from the endpoint label alone.
Over-dispersion is a general concern when observed variation exceeds what a statistical model expects. If a model assumes less variability than the data contain, uncertainty may be understated. Conversely, an unsuitable model may lose precision or misrepresent the distribution. The registry record does not identify a model for the AUC results, so it is not possible to assess whether over-dispersion was examined or how variability was handled.
What is not described about the analysis?
The registry record does not report a sample-size justification, a prespecified statistical analysis plan, interim analyses, handling of multiple outcomes, or a hierarchy of comparisons. The study’s enrollment value alone does not reveal the intended precision or ability to detect a particular effect. No sample-size calculation should be inferred from it. The record also does not describe transformations, covariate adjustment, outlier handling, or sensitivity analyses.
These absences limit what can be concluded from the registry information, but they do not establish that a method was or was not used in study conduct. The appropriate reading is narrower: the methods and numerical primary results needed to assess the endpoint statistically are not reported in the registry record. General explanations of AUC, variation, randomization, and confidence intervals describe statistical concepts and are not claims about analyses performed in this trial.
10. Multiplicity, Missing Data and Analysis Populations
The primary outcome includes several AUC definitions and measurement occasions, and the record also names secondary pharmacodynamic outcomes. Multiple outcomes or comparisons can raise a multiplicity question: when many hypotheses are assessed, the chance of at least one apparently notable result can increase. Statistical plans may address this by specifying a primary contrast, using an adjustment, or treating some outcomes as exploratory. The registry record does not report a multiplicity strategy, testing hierarchy, or a defined set of formal comparisons. It is not appropriate to assume that an adjustment was or was not performed.
The primary outcome description identifies active-treatment arms and gives selected analysis counts, but does not define a full analysis population or state whether all randomized participants were included in a primary analysis. The registry does not report participant flow, endpoint-specific reasons for missing data, or rules for excluding observations. It also does not describe imputation or sensitivity analyses. As general context, missing data may affect an estimate if the likelihood of missingness relates to participant characteristics or outcomes; the direction and extent of any effect depend on circumstances not described in this record.
The record lists six outcome measures and 0 analyses. It does not clarify whether the analysis count refers to entered registry results, prespecified statistical analyses, or another registry feature. Thus, it cannot establish that no analyses were conducted. The multiplicity approach, missing-data methods, and analysis-population definitions are not reported in the registry record.
11. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| IDN-6556 5 mg | 3 | 5 | 60.0% |
| IDN-6556 25 mg | 6 | 7 | 85.7% |
| IDN-6556 50 mg | 3 | 5 | 60.0% |
| Placebo | 2 | 4 | 50.0% |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| IDN-6556 5 mg | 3 of 5 |
| IDN-6556 25 mg | 7 of 7 |
| IDN-6556 50 mg | 4 of 5 |
| Placebo | 3 of 4 |
Most frequent serious adverse event terms
| Event term | Organ system | IDN-6556 5 mg | IDN-6556 25 mg | IDN-6556 50 mg | Placebo |
|---|---|---|---|---|---|
| Gastrointestinal haemorrhage | Gastrointestinal disorders | 1 of 5 | 0 of 7 | 2 of 5 | 0 of 4 |
| Multi-organ failure | General disorders | 1 of 5 | 1 of 7 | 0 of 5 | 1 of 4 |
| Nausea | Gastrointestinal disorders | 0 of 5 | 0 of 7 | 0 of 5 | 1 of 4 |
| Gastric varices haemorrhage | Gastrointestinal disorders | 0 of 5 | 0 of 7 | 0 of 5 | 1 of 4 |
| Ascites | Gastrointestinal disorders | 0 of 5 | 1 of 7 | 0 of 5 | 0 of 4 |
| Abdominal pain | Gastrointestinal disorders | 0 of 5 | 1 of 7 | 0 of 5 | 0 of 4 |
| Oesophageal varices haemorrhage | Gastrointestinal disorders | 0 of 5 | 1 of 7 | 0 of 5 | 0 of 4 |
| Hepatic cirrhosis | Hepatobiliary disorders | 0 of 5 | 0 of 7 | 0 of 5 | 1 of 4 |
| Alcoholic liver disease | Hepatobiliary disorders | 1 of 5 | 0 of 7 | 0 of 5 | 0 of 4 |
| Acute hepatic failure | Hepatobiliary disorders | 0 of 5 | 1 of 7 | 0 of 5 | 0 of 4 |
Most frequent non-serious adverse event terms
| Event term | Organ system | IDN-6556 5 mg | IDN-6556 25 mg | IDN-6556 50 mg | Placebo |
|---|---|---|---|---|---|
| Gastrointestinal disorders | Gastrointestinal disorders | 3 of 5 | 7 of 7 | 4 of 5 | 3 of 4 |
| Nervous system disorders | Nervous system disorders | 2 of 5 | 4 of 7 | 2 of 5 | 0 of 4 |
| General disorders and administration site conditions | General disorders | 1 of 5 | 3 of 7 | 2 of 5 | 1 of 4 |
| Hepatobiliary disorders | Hepatobiliary disorders | 2 of 5 | 3 of 7 | 1 of 5 | 1 of 4 |
| Respiratory, thoracic and mediastinal disorders | Respiratory, thoracic and mediastinal disorders | 1 of 5 | 4 of 7 | 0 of 5 | 2 of 4 |
| Investigations | Investigations | 1 of 5 | 1 of 7 | 0 of 5 | 3 of 4 |
| Metabolism and nutrition disorders | Metabolism and nutrition disorders | 0 of 5 | 2 of 7 | 3 of 5 | 0 of 4 |
| Infections and infestations | Infections and infestations | 1 of 5 | 2 of 7 | 1 of 5 | 0 of 4 |
| Psychiatric disorders | Psychiatric disorders | 1 of 5 | 2 of 7 | 1 of 5 | 0 of 4 |
| Musculoskeletal and connective tissue disorders | Musculoskeletal and connective tissue disorders | 0 of 5 | 2 of 7 | 0 of 5 | 1 of 4 |
Serious events with the highest arm-level rate: gastrointestinal haemorrhage (40.0%), nausea (25.0%), gastric varices haemorrhage (25.0%), multi-organ failure (25.0%), hepatic cirrhosis (25.0%).
The serious adverse event counts are presented by group as participants at risk and participants affected. The listed figures are 5 at risk and 3 affected for IDN-6556 5 mg; 7 and 6 for IDN-6556 25 mg; 5 and 3 for IDN-6556 50 mg; and 4 and 2 for placebo. These are descriptive counts. They do not show whether events were judged related to treatment, how long participants were followed for safety, or whether differences between groups are statistically reliable.
The record also lists serious adverse event terms with percentages: Gastrointestinal haemorrhage, 40.0%; Nausea, 25.0%; Gastric varices haemorrhage, 25.0%; Multi-organ failure, 25.0%; Hepatic cirrhosis, 25.0%; and Dyspnoea, 25.0%. The record does not give the denominator or explain the basis for these percentages, so they should not be interpreted as percentages of all enrolled participants or as comparative risks between arms.
Death counts are listed as null for each group. This means death information is not reported in the registry record, not that the count is zero. The record does not include a full event listing or a method for comparing serious events across treatment groups.
12. What the Result Does, and Does Not, Mean
The registry record supports a limited description of the study: it was randomized, placebo-controlled, and conducted in parallel groups, with three twice-daily IDN-6556 dose arms and a twice-daily placebo arm. It identifies AUC as the primary endpoint and provides selected endpoint-specific analysis counts. It also gives group-level serious adverse event counts and a list of serious event terms with percentages.
Those details do not establish what the pharmacokinetic results were. No AUC estimates or measures of uncertainty are reported, so the record does not show whether exposure differed across doses, how large any differences were, or how precisely they were estimated. No formal comparison or p-value is reported. Consequently, the registry information cannot support a claim that IDN-6556 did or did not produce a particular exposure pattern, or that any clinical outcome improved or worsened.
The safety data also have limits. Counts can describe the events recorded in each group, but without a reported comparative analysis, full follow-up information, and clear event denominators, they cannot establish a reliable difference in safety between treatment groups. Null death entries are missing reports, not evidence of no deaths. Percentages attached to serious event terms lack a stated denominator in the registry record.
These limitations do not mean that the study produced no findings; they mean that the registry record does not report the information needed to evaluate those findings. Likewise, the terminated status is a status label, not an explanation of why the study stopped or what consequences that had for the results. The reason for termination is not reported in the registry record.
The distinction is between what the record documents and what a reader might want to know. It documents the study design, its endpoint definitions, selected analysis counts, and descriptive safety information. It does not provide the primary endpoint values, complete analysis methods, or a comparative efficacy or safety conclusion. Interpretation should remain within those limits.
13. Why This Trial Matters Statistically
This study is statistically interesting because it combines pharmacokinetic measurement with pharmacodynamic and safety aims in a randomized, placebo-controlled design. AUC endpoints focus on drug exposure, while the listed secondary measures—CK18/M30, CK18/M65, and Caspase 3/7 RLU—address different biological measurements. That breadth makes clear why endpoint definitions and a prespecified analysis plan matter: different outcomes answer different questions and may have different measurement properties.
The available counts show that the number of analyzed participants was not the same for every reported dose and measurement occasion. This illustrates a practical issue in clinical research: overall enrollment does not necessarily describe the information available for each endpoint. For readers assessing an estimate, endpoint-specific denominators, missing-data explanations, and uncertainty measures are important. In this record, the selected counts are available, but the corresponding exposure summaries and reasons for differing counts are not.
The record also demonstrates the distinction between descriptive safety reporting and comparative inference. A count of affected participants can be useful context, but interpretation across groups depends on definitions, exposure to follow-up, denominators, and an appropriate comparative method. The registry’s serious-event figures do not include enough information to make that comparison.
Finally, the trial’s terminated status makes transparent reporting particularly important, but status alone does not explain the study’s history. The registry does not report a termination reason or the statistical plan. These omissions limit assessment of how the analyses relate to the original objectives. The statistical lesson is not a conclusion about the intervention; it is that design details and endpoint labels cannot replace reported estimates, uncertainty, and methods.
14. Limitations
- The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
- Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.
The main limitation of the registry record is that it names the primary AUC endpoints but does not include their numerical results. Without geometric means and geometric coefficients of variation, readers cannot assess the observed exposure patterns or their variability. The absence of confidence intervals and formal comparisons further prevents evaluation of precision and between-group differences.
Analysis-population reporting is incomplete. The record gives selected counts for AUC 0-last and AUC 0-inf, but not a complete set of counts for all endpoint definitions, arms, and days. It does not explain why the listed counts differ, how missing measurements were handled, or which participants were included in each analysis. Although enrollment is listed as 23, it cannot stand in for endpoint-specific denominators.
The statistical methods are also not fully described. The registry does not report a sample-size justification, analysis model, multiplicity strategy, interim analyses, or a prespecified plan for defining the analysis populations. It does not state whether the AUC outcomes were adjusted for baseline or other covariates, or whether sensitivity analyses were conducted. The record’s analysis count of 0 does not clarify the status of analyses outside registry reporting.
Safety interpretation is constrained by limited detail. The serious adverse event counts lack a comparative analysis and the event-term percentages have no stated denominator. Death data are null rather than explicitly reported as zero. The duration of safety observation and full event definitions are not described in the information available.
The registry lists both triple masking and an official-title description of double-blinding, but does not explain the procedures. It also lists terminated status without a reason. These gaps leave uncertainty about study conduct and reporting context; they should not be resolved by assumption.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Pharmacokinetic and Pharmacodynamic Study of IDN-6556 in ACLF — NCT01937130.
- Registry record last updated 2016-04-11; status last verified 2016-03.
- Results first posted 2016-04-11.
- Data retrieved from ClinicalTrials.gov on 2026-11-09.
- Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.
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18. Record Summary
The registry describes NCT01937130 as a Phase 2, randomized, parallel-group, placebo-controlled study of IDN-6556 in subjects with cirrhosis hospitalized for acute deterioration of liver function. It lists three active dose arms—5 mg, 25 mg, and 50 mg—and placebo, all dosed twice daily. Enrollment is recorded as 23. The study started in 2013-09, had primary completion in 2015-01, and is listed as terminated.
The primary outcome is AUC in h*ng/mL, summarized by geometric mean and geometric coefficient of variation, with a stated timeframe of 28 days. Endpoint definitions include AUC 0-8, AUC 0-last, and AUC 0-inf on Day 1 and Day 4. Selected analysis counts and descriptive serious adverse event information are reported, but numerical primary outcome results, formal comparisons, and a complete statistical analysis plan are not reported in the registry record.