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 Study to Investigate the Influence of Hepatic Insufficiency on the Pharmacokinetics of Grazoprevir (MK-5172-013) (NCT01390428), a non-randomized phase 1 study. The primary outcome is Area Under the Concentration Time-curve From 0 to 24 Hours (AUC0-24) of Grazoprevir.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01390428 |
| Phase | Phase 1 |
| Condition | Hepatitis C |
| Allocation | Non-Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 50 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Merck Sharp & Dohme LLC |
| Results posted | Yes |
2. Clinical Question
Population
Participants with mild, moderate, or severe hepatic impairment, classified using the Child-Pugh scale, and healthy participants matched to the impairment groups. The registry record lists Hepatitis C as a condition, but does not give further detail about the characteristics of the enrolled participants.
Intervention
Grazoprevir given once a day for 10 consecutive days. The dose was 200 mg in Part 1, 100 mg in Part 2, and 50 mg in Part 3.
Comparator
Healthy participants matched to each hepatic-impairment group, receiving the same dose and schedule as the corresponding impairment group. Allocation was non-randomized, so these are not randomized control groups.
Primary question
How does the plasma exposure to grazoprevir, measured by the area under the concentration-time curve from 0 to 24 hours, differ between participants with hepatic impairment and healthy participants?
The study focuses on pharmacokinetics: the measurement of drug concentrations over time, rather than a clinical outcome such as symptom improvement or disease progression. Its primary endpoint is AUC0-24, assessed on Days 1 and 10. The registry record specifies that the impairment categories follow Child-Pugh scores: 5-6 for mild, 7-9 for moderate, and 10-15 for severe impairment.
The question is addressed separately across the three study parts. In each part, participants with an impairment category are compared with healthy participants matched to that category, and both groups receive the same dose. This structure allows the pharmacokinetic question to be considered at the dose used in each part. Because allocation was non-randomized, the groups should not be interpreted as randomized, exchangeable arms. The registry record does not report numerical AUC0-24 results, so the magnitude or direction of any exposure difference cannot be described from the posted results.
3. Trial Design
This was a completed Phase 1, open-label, non-randomized, parallel study with three parts. The registry record lists enrollment of 50 participants, a start date of 2011-07-28, and primary completion on 2014-09-05. Grazoprevir was the study drug. The stated purpose was to compare its pharmacokinetics in participants with hepatic impairment and healthy participants.
Each part addressed a different severity category. In Part 1, participants with mild hepatic impairment and healthy participants matched to them received 200 mg once a day for 10 consecutive days. In Part 2, participants with moderate impairment and their healthy matched group received 100 mg once a day for 10 consecutive days. In Part 3, participants with severe impairment and their healthy matched group received 50 mg once a day for 10 consecutive days. The parts therefore combine different impairment categories with different dose levels; comparisons across parts would not isolate impairment severity from dose.
Open-label means that masking was not used, as recorded in the registry. Non-randomized allocation means assignment to the listed groups was not random. The registry record does not report the allocation procedure, recruitment process, or the reason for choosing the different doses. It also does not report whether there were protocol changes during the study.
The design is suited to describing pharmacokinetic measurements under the study’s specified conditions. It is not a randomized efficacy trial, and the healthy matched groups are not randomized controls. Matching may make groups more comparable on characteristics used for matching, but the registry record does not state which characteristics were used or how matching was performed. Consequently, the design alone cannot establish that any observed difference in exposure was caused solely by hepatic impairment.
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.
Overall Study
| Stage | Part 1-Mild Hepatic Impairment (HI) | Part 1-Healthy Matched to Mild HI | Part 2-Moderate HI | Part 2-Healthy Matched to Moderate HI | Part 3-Severe HI | Part 3-Healthy Matched to Severe HI |
|---|---|---|---|---|---|---|
| STARTED | 8 | 8 | 9 | 9 | 8 | 8 |
| COMPLETED | 8 | 8 | 8 | 9 | 7 | 8 |
| NOT COMPLETED | 0 | 0 | 1 | 0 | 1 | 0 |
Reasons for not completing this period:
| Reason | Part 1-Mild Hepatic Impairment (HI) | Part 1-Healthy Matched to Mild HI | Part 2-Moderate HI | Part 2-Healthy Matched to Moderate HI | Part 3-Severe HI | Part 3-Healthy Matched to Severe HI |
|---|---|---|---|---|---|---|
| Elective Surgery | 0 | 0 | 0 | 0 | 1 | 0 |
| Withdrawal by Subject | 0 | 0 | 1 | 0 | 0 | 0 |
Analysis population for the primary outcome, as defined in the registry: Participants who comply with the protocol sufficiently to ensure that these data will be likely to exhibit the effects of treatment, according to the underlying scientific model.
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.
Only the first 6 of 7 groups are shown.
| Characteristic | Unit | Part 1-Mild HI | Part 1-Healthy Matched to Mild HI | Part 2-Moderate HI | Part 2-Healthy Matched to Moderate HI | Part 3-Severe HI | Part 3-Healthy Matched to Severe HI |
|---|---|---|---|---|---|---|---|
| Participants analysed | 8 | 8 | 9 | 9 | 8 | 8 | |
| Age, Continuous | Years | 54.1 (SD 4.1) | 54.5 (SD 5.8) | 53.3 (SD 6.7) | 52.3 (SD 6.8) | 52.1 (SD 8.4) | 52.0 (SD 9.9) |
| Sex: Female, Male: Female | Participants | 3 | 3 | 0 | 0 | 3 | 3 |
| Sex: Female, Male: Male | Participants | 5 | 5 | 9 | 9 | 5 | 5 |
6. Primary Endpoint
The registry lists the primary outcome as Area Under the Concentration Time-curve From 0 to 24 Hours (AUC0-24) of Grazoprevir, measured over Days 1 and 10 at the following timepoints: pre-dose, 0.5, 1, 1.5, 2, 3, 4, 6, 8, 12, 16 and 24 hours post-dose.
| Element | Registry entry |
|---|---|
| Result type | Geometric Mean |
| Measure of spread | 95% Confidence Interval |
| Unit | uM*hr |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is the area under the plasma concentration-time curve from 0 to 24 hours, abbreviated AUC0-24, for grazoprevir. It is measured in uM*hr. The registry record identifies the endpoint summary as a geometric mean with a 95% confidence interval. Blood samples were scheduled before dosing and at 0.5, 1, 1.5, 2, 3, 4, 6, 8, 12, 16, and 24 hours after dosing on Days 1 and 10.
AUC represents cumulative drug exposure over a defined time interval. It uses information across the concentration-time profile rather than relying on a single blood concentration. The 0-to-24-hour interval provides a defined window for comparing exposure after dosing. Measurements on Day 1 and Day 10 allow the endpoint to be assessed at two points during the repeated-dose schedule. The registry record does not state how any difference between those days was modeled or tested.
Geometric means are commonly used for positive measurements that may be right-skewed, as pharmacokinetic measures can be. A 95% confidence interval describes uncertainty around an estimated quantity under the statistical model used; it is not a range expected to contain most individual participants’ values. These are general statistical interpretations. Numerical geometric means and confidence intervals for AUC0-24 are not reported in the registry record, so the posted results do not establish the observed exposure in any group or the precision of a between-group contrast.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record describes a pharmacokinetic question, not a test of clinical benefit. The primary measure, AUC0-24, is intended to characterize grazoprevir exposure over a defined period after dosing. The record specifies the measurement schedule, dose schedules, impairment categories, and the planned form of the endpoint summary. It does not report numerical AUC0-24 values or numerical confidence intervals. Without those results, the direction, magnitude, and precision of exposure differences between the impairment groups and their healthy matches cannot be assessed.
The comparison structure matters. Within each part, the impairment group and its healthy matched group received the same dose. Those within-part comparisons are the ones aligned with the stated question. The three parts used different dose levels, so differences between Part 1, Part 2, and Part 3 cannot be read as a clean comparison of severity alone. Both impairment category and dose vary across parts. The record does not report a statistical model that adjusts or otherwise accounts for those differences.
Non-randomized allocation also limits interpretation. A difference between groups could reflect hepatic status, but it could also be associated with other differences between the enrolled groups. The registry record does not identify the matching factors, report baseline characteristics, or provide enough detail to judge how well the groups were balanced. Matching is not equivalent to randomization, and it does not guarantee comparability on factors that were not matched or measured.
The endpoint description says that the geometric mean and 95% confidence interval were the intended summary. Confidence intervals are useful because they show the uncertainty associated with an estimate, but their width and location are needed to judge how precise a result is and which values remain compatible with the data. Since numerical estimates are not reported in the registry record, neither the point estimates nor their uncertainty can be interpreted. No p-value or direct statistical test for the primary contrast is reported in the registry record.
The registry lists 50 participants enrolled, but the endpoint-specific analysis counts are not reported in the registry record. Enrollment does not establish how many participants contributed usable pharmacokinetic data, whether all planned samples were collected, or how missing measurements were handled. The outcome population is described in terms of participants complying with the protocol sufficiently for their data to reflect treatment effects under the underlying scientific model. The record does not give the operational criteria used to determine inclusion in that population.
These limitations mean that the posted information supports a description of the study question and its measurement plan, but not a conclusion about the size or direction of the pharmacokinetic findings. The record also does not report evidence that would support conclusions about clinical outcomes. Any interpretation should remain specific to the described doses, schedule, impairment categories, and study groups, and should not be generalized beyond those conditions on the basis of the registry information alone.
9. Statistical Methods Explained
What does AUC0-24 measure?
A concentration-time profile records the amount of drug measured in blood at different times after dosing. AUC0-24 integrates that profile over the interval from 0 to 24 hours. In general, a larger AUC indicates greater total measured exposure during that interval, while a smaller AUC indicates less exposure during that interval. This is a general interpretation of the measure, not a statement about the results of this study. The registry record does not report the numerical AUC values.
For this study, blood was collected before dosing and at the listed post-dose times on Days 1 and 10. The scheduled times capture measurements across the first 24 hours after dosing. The primary endpoint is defined as AUC0-24 on both of those study days. The registry record does not report the calculation method used to derive AUC from the individual concentrations, such as the specific interpolation or integration procedure.
Why report a geometric mean?
A geometric mean summarizes positive values by working on a logarithmic scale and then returning to the original scale. As a general statistical approach, it can be useful when measurements are right-skewed, because a few high values can pull an arithmetic mean upward. Pharmacokinetic exposure measures are often positive and may have skewed distributions, which is one reason geometric summaries are used in this field. The endpoint definition in the registry identifies the geometric mean as the summary measure, but does not report whether a transformation was used in the analysis or specify the model used to estimate it.
A geometric mean is not the same as the arithmetic average, and it should not be interpreted as describing every participant’s exposure. It summarizes a group-level distribution. To understand how much participants vary around that summary, additional information such as dispersion or individual-level data would be needed. Those details are not reported in the registry record for the primary endpoint.
How should a 95% confidence interval be read?
A confidence interval expresses uncertainty in an estimate under the assumptions of the statistical procedure. In general, a narrower interval indicates greater precision than a wider interval, while the interval’s position indicates which values are compatible with the estimate and its uncertainty. A 95% confidence interval is not a statement that 95% of individual participants’ values fall inside its limits. It is also not, by itself, a test of whether a between-group difference is statistically significant.
The registry record specifies a 95% confidence interval for the geometric mean. It does not provide its limits for any group or contrast. Consequently, the precision of the endpoint estimates cannot be judged from the posted results. The exact confidence-interval procedure and any assumptions used to construct it are not reported in the registry record.
Why are the within-part comparisons important?
In each part, participants with a particular impairment category were compared with healthy participants matched to that category, and both groups received the same dose. This is the design feature most directly related to the stated question about hepatic impairment and grazoprevir pharmacokinetics. The doses differed among parts, so comparing results across parts would mix severity differences with dose differences. This is a general design interpretation; the registry record does not report a cross-part statistical model or pooled analysis.
Non-randomized allocation leaves room for differences between groups apart from impairment status. For example, a statistical comparison can account only for measured factors included in the model, and the registry record does not identify the matching factors or report adjustment variables. The record also does not state whether the primary comparison was a ratio of geometric means, a difference on a transformed scale, or another contrast. Such methods are common in pharmacokinetic work, but the specific analysis cannot be assumed.
What is over-dispersion, and is it relevant?
Over-dispersion is a general statistical issue in which observed variability is greater than a model expects. It is especially relevant to some count outcomes when a standard count model assumes more uniform variation than the data exhibit. The primary outcome in this study is a continuous pharmacokinetic measure, not a count outcome, so a count-model over-dispersion adjustment should not be presumed. The registry record does not report the distributional checks, model diagnostics, or handling of unusual values used for the pharmacokinetic analysis.
What can be inferred from the enrollment and planning information?
The registry lists enrollment of 50 participants. That figure describes the recorded enrollment, not necessarily the number with evaluable AUC data or the number included in each endpoint analysis. The endpoint-specific analysis population and group counts are not reported in the registry record. The reason for the enrollment target, including any sample-size justification, is also not reported in the registry record.
Any sample-size planning illustration is a conditional calculation, not observed power and not evidence of the study’s probability of detecting an effect. The registry record describes a planning approach based on an observed effect, equal allocation, a two-sided significance level of 0.05, and a normal approximation, with the target effect expressed as a fraction of that observed effect. It also distinguishes participant counts per arm from total event counts for time-to-event calculations. These assumptions describe an illustration and should not be mistaken for the trial’s original design rationale. No numerical planning result or original sample-size justification is reported in the registry record.
10. Multiplicity, Missing Data and Analysis Populations
The primary endpoint is identified as AUC0-24, with measurements on Days 1 and 10. The study also has multiple impairment categories and matched healthy groups, creating several potential comparisons. The registry record does not report which contrasts were designated as primary statistical comparisons, whether separate hypotheses were tested for each part or day, or whether any multiplicity adjustment was planned or applied.
Multiplicity is the general issue that arises when several statistical tests or outcomes are considered. If many tests are conducted, the chance of at least one apparently unusual result can increase unless the analysis plan accounts for that testing structure. This does not mean an adjustment must always be used; the appropriate approach depends on the scientific objectives and prespecified analysis plan. That plan is not reported in the registry record. The record lists seven outcome measures and 17 analyses, but does not describe how they relate to any multiplicity strategy.
The primary endpoint population is described as participants who comply with the protocol sufficiently to ensure that the data are likely to exhibit treatment effects according to the underlying scientific model. The registry record does not define the compliance criteria, state how many participants met them, or report whether all enrolled participants were included in each analysis. It does not report how missing samples, incomplete concentration profiles, or measurements outside expected ranges were handled.
Missing-data methods can affect an estimate when unavailable measurements are related to participant characteristics or exposure. As a general principle, the analysis should clarify which observations were available, how incomplete profiles were treated, and whether assumptions were needed to estimate the endpoint. Those details are not reported in the registry record. The statistical analysis plan, interim analyses, and procedures for selecting or excluding pharmacokinetic observations are also 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 |
|---|---|---|---|
| Part 1-Mild HI | 0 | 8 | 0.0% |
| Part 1-Healthy Matched to Mild HI | 0 | 8 | 0.0% |
| Part 2-Moderate HI | 0 | 9 | 0.0% |
| Part 2-Healthy Matched to Moderate HI | 0 | 9 | 0.0% |
| Part 3-Severe HI | 1 | 8 | 12.5% |
| Part 3-Healthy Matched to Severe HI | 0 | 8 | 0.0% |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 5% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Part 1-Mild HI | 8 of 8 |
| Part 1-Healthy Matched to Mild HI | 5 of 8 |
| Part 2-Moderate HI | 4 of 9 |
| Part 2-Healthy Matched to Moderate HI | 4 of 9 |
| Part 3-Severe HI | 4 of 8 |
| Part 3-Healthy Matched to Severe HI | 3 of 8 |
Most frequent serious adverse event terms
| Event term | Organ system | Part 1-Mild HI | Part 1-Healthy Matched to Mild HI | Part 2-Moderate HI | Part 2-Healthy Matched to Moderate HI | Part 3-Severe HI | Part 3-Healthy Matched to Severe HI |
|---|---|---|---|---|---|---|---|
| Postoperative ileus | Injury, poisoning and procedural complications | 0 of 8 | 0 of 8 | 0 of 9 | 0 of 9 | 1 of 8 | 0 of 8 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Part 1-Mild HI | Part 1-Healthy Matched to Mild HI | Part 2-Moderate HI | Part 2-Healthy Matched to Moderate HI | Part 3-Severe HI | Part 3-Healthy Matched to Severe HI |
|---|---|---|---|---|---|---|---|
| Headache | Nervous system disorders | 3 of 8 | 2 of 8 | 0 of 9 | 1 of 9 | 1 of 8 | 1 of 8 |
| Diarrhoea | Gastrointestinal disorders | 2 of 8 | 0 of 8 | 0 of 9 | 0 of 9 | 0 of 8 | 1 of 8 |
| Fatigue | General disorders | 1 of 8 | 1 of 8 | 0 of 9 | 1 of 9 | 0 of 8 | 0 of 8 |
| Dizziness | Nervous system disorders | 2 of 8 | 0 of 8 | 0 of 9 | 1 of 9 | 0 of 8 | 0 of 8 |
| Vomiting | Gastrointestinal disorders | 0 of 8 | 0 of 8 | 1 of 9 | 1 of 9 | 0 of 8 | 0 of 8 |
| Pain | General disorders | 0 of 8 | 1 of 8 | 0 of 9 | 0 of 9 | 1 of 8 | 0 of 8 |
| Myalgia | Musculoskeletal and connective tissue disorders | 1 of 8 | 1 of 8 | 0 of 9 | 0 of 9 | 0 of 8 | 0 of 8 |
| Lethargy | Nervous system disorders | 1 of 8 | 1 of 8 | 0 of 9 | 0 of 9 | 0 of 8 | 0 of 8 |
| Insomnia | Psychiatric disorders | 0 of 8 | 1 of 8 | 0 of 9 | 1 of 9 | 0 of 8 | 0 of 8 |
| Epistaxis | Respiratory, thoracic and mediastinal disorders | 0 of 8 | 1 of 8 | 0 of 9 | 0 of 9 | 1 of 8 | 0 of 8 |
Serious events with the highest arm-level rate: postoperative ileus (12.5%).
The registry reports serious adverse event counts by study group. The count of participants affected by a serious adverse event is 0 among 8 at risk in Part 1-Mild HI, 0 among 8 in Part 1-Healthy Matched to Mild HI, 0 among 9 in Part 2-Moderate HI, 0 among 9 in Part 2-Healthy Matched to Moderate HI, 1 among 8 in Part 3-Severe HI, and 0 among 8 in Part 3-Healthy Matched to Severe HI. These are descriptive counts. The record does not establish that the event was caused by grazoprevir.
The listed top serious term is postoperative ileus, with 12.5% recorded. The registry record does not provide further context for that term in the information available, so it should not be assigned to a particular group or interpreted as a comparative risk estimate without additional details. Death counts are not reported in the registry record.
Other adverse events were recorded in 8 of 8 participants in Part 1-Mild HI, 5 of 8 in its healthy matched group, 4 of 9 in Part 2-Moderate HI, 4 of 9 in its healthy matched group, 4 of 8 in Part 3-Severe HI, and 3 of 8 in its healthy matched group. These figures describe the registry’s affected-participant counts for other adverse events; they do not indicate severity, duration, or causality. Because the study was non-randomized and the groups are small, raw counts should not be treated as a reliable causal comparison. The registry record does not give event-level detail or a statistical comparison of safety outcomes.
12. What the Result Does, and Does Not, Mean
The study’s stated purpose was to compare grazoprevir pharmacokinetics in participants with hepatic impairment and healthy matched participants. The primary endpoint is clearly identified as AUC0-24, and the registry specifies the sampling schedule, the geometric-mean summary, and a 95% confidence interval. These details explain what the study was designed to measure. They do not, on their own, show what the measurements were.
Numerical results for the primary endpoint are not reported in the registry record. Therefore, the posted results do not establish whether the measured exposure was higher, lower, or similar in any impairment group relative to its healthy matched group. They also do not show how precise an estimate was, because endpoint confidence-interval limits are not reported. No statistical significance claim about the primary comparisons can be made from the endpoint information described in the registry record.
Even if numerical group estimates were available, interpretation would need to account for the non-randomized design, the matching procedure, the different doses used across parts, and the number of participants contributing endpoint data. The registry record does not report enough information to evaluate these factors fully. In particular, differences across parts would not isolate the effect of impairment severity because dose and impairment category vary together.
The pharmacokinetic endpoint is not itself a measure of clinical benefit or harm. It describes drug exposure over a specified interval. It cannot establish whether participants experienced improved health outcomes, and the registry information does not report such an efficacy result. Similarly, adverse-event counts are descriptive and do not by themselves establish causation or comparative safety.
The result should therefore be understood as a registered Phase 1 pharmacokinetic investigation with a defined endpoint and group structure, but without numerical primary outcome estimates in the registry record. Conclusions about exposure differences, their precision, or their clinical implications require results and analysis details that are not reported in the registry record.
13. Why This Trial Matters Statistically
This study illustrates the importance of matching the statistical question to the endpoint. Pharmacokinetics concerns concentration and exposure over time. AUC0-24 condenses a series of timed blood measurements into a measure of cumulative exposure over a defined interval. The endpoint description is therefore more informative than a single concentration measurement for understanding the study’s intended comparison of drug exposure.
The study also highlights why dose and group structure must be read together. Within each part, the impairment group and its healthy matched group received the same dose, making those comparisons the direct focus of the stated question. Across parts, both the impairment category and dose change. A contrast between parts would therefore combine more than one design feature, and should not be interpreted as an isolated severity effect.
The non-randomized design is another important statistical feature. Matching may address selected differences between participants, but it does not have the same role as random allocation. Since the registry record does not specify matching factors or report baseline comparisons, readers cannot assess the degree of group comparability. This is a useful reminder that statistical interpretation depends not only on the endpoint, but also on how groups were assembled.
Finally, a clear endpoint definition is not a substitute for numerical results. The registry states the intended summary and confidence-interval type, but does not report the estimates needed to judge direction, size, or precision. Distinguishing a well-described measurement plan from evidence about the observed outcome is central to reading registry records responsibly. The reported safety counts likewise require cautious interpretation because they are descriptive and arise from non-randomized groups.
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 for interpreting the pharmacokinetic question is the absence of numerical primary endpoint results in the registry record. Group-specific AUC0-24 estimates, confidence-interval limits, endpoint analysis counts, and between-group contrasts are not reported. Without those details, the exposure findings and their precision cannot be assessed.
The allocation was non-randomized and masking was not used. The registry record does not describe how participants were assigned to groups or which characteristics were used for matching. It also does not report baseline characteristics that would help assess group comparability. Residual differences between groups could therefore affect an observed contrast, if one were reported.
The three parts use different doses for different impairment categories. This means comparisons across parts would combine dose and impairment differences. The record does not report a model intended to separate those factors. The registry also does not report the sample-size justification, the statistical analysis plan, any interim analyses, or the method used to calculate AUC from concentration measurements.
Information about missing data and analysis populations is limited. The described endpoint population is not accompanied by operational inclusion criteria or counts of participants with evaluable data. Handling of missing samples, incomplete profiles, protocol deviations, or unusual measurements is not reported in the registry record. Multiplicity procedures for the several outcomes and analyses are also not reported.
Safety information is presented as group counts, but the registry record does not supply event-level detail, causality assessments, or comparative statistical analyses. Death counts are not reported in the registry record. These constraints make the safety figures descriptive rather than a basis for causal conclusions.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Study to Investigate the Influence of Hepatic Insufficiency on the Pharmacokinetics of Grazoprevir (MK-5172-013) — NCT01390428.
- Registry record last updated 2018-09-14; status last verified 2018-08.
- Results first posted 2016-03-04.
- 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 record identifies NCT01390428 as a completed Phase 1, open-label, non-randomized, parallel study of grazoprevir pharmacokinetics in participants with hepatic impairment and healthy matched participants. Enrollment was 50. The record lists a start date of 2011-07-28 and primary completion on 2014-09-05.
The study had three parts corresponding to mild, moderate, and severe hepatic impairment. Each part used a different once-daily dose for 10 consecutive days, and the matched healthy group received the same dose as its impairment group. The primary endpoint was AUC0-24, summarized as a geometric mean with a 95% confidence interval.
Numerical primary endpoint estimates and their confidence intervals are not reported in the registry record. The record also does not report the primary analysis method, missing-data procedures, multiplicity handling, or sample-size justification. Serious and other adverse-event counts are listed by group, but they are descriptive and do not establish causation.