A Study to Evaluate the Effect of Hepatic Impairment on the Single Dose Pharmacokinetics (PK) of Intravenous TAK-954: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for A Study to Evaluate the Effect of Hepatic Impairment on the Single Dose Pharmacokinetics (PK) of Intravenous TAK-954 (NCT03277274), a non-randomized phase 1 study. The primary outcome is Cmax: Maximum Observed Plasma Concentration for TAK-954 (Total and Free).

2. Clinical Question

This is a pharmacokinetic question: it concerns drug concentrations in plasma rather than a clinical benefit outcome. The primary endpoint is described as Cmax for total and free TAK-954, with concentration measured in nanograms per milliliter. Samples were scheduled before infusion on Day 1 and at multiple time points up to 96 hours after infusion.

The comparison is descriptive and pharmacokinetic in focus. Because participants were not randomly assigned to hepatic-function groups, group differences may reflect characteristics associated with those groups as well as hepatic function. The registry record does not report the numerical Cmax estimates, their variability, or a formal estimate of the differences between groups. Consequently, the clinical question can be identified from the design and endpoint, but its numerical answer is not reported in the registry record.

3. Trial Design

The registry record describes a Phase 1, non-randomized, open-label, sequential trial of intravenous TAK-954. It is listed as completed. The study purpose was to evaluate whether varying degrees of hepatic function relate to the pharmacokinetics of a single dose. The listed conditions are hepatic impairment and healthy volunteers.

Participants in the mild, moderate, and severe hepatic impairment groups, as well as healthy participants, were assigned TAK-954 0.2 mg. Each group description specifies intravenous administration as a 60-minute infusion once on Day 1. The study is not described as a randomized comparison: the registry record gives allocation as non-randomized, masking as none, and the model as sequential. Therefore, group labels describe the participant cohorts rather than randomized treatment assignments.

The registry record lists enrollment as 25. It does not report the number enrolled in each group in the registry record for this account. The listed primary endpoint is Cmax for total and free TAK-954. The pharmacokinetic set is described as participants who were enrolled, received the correct dose, and had at least one measurable plasma concentration or amount of drug in urine for TAK-954.

Start is recorded as 2017-11-09, and primary completion as 2018-09-01. These dates describe the study record, not the timing of any individual participant’s measurements. The record also lists eight outcome measures and 12 analyses, but detailed numerical results and the statistical analysis plan are not reported in the registry record. As a result, the design can be described, but the planned inferential approach and the primary endpoint findings cannot be reconstructed from the information.

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: Participants with normal hepatic function and hepatic impairment were enrolled in 1 of the groups:B(moderate), C(severe) or D(healthy) to receive TAK-954 0.2mg. Based on available safety and PK data from Group B, participants were enrolled in reduced study design and were not enrolled in GroupA(mild). Groups A-D are equal to Groups 1-4 in protocol.

Overall Study

Analysis population for the primary outcome, as defined in the registry: The pharmacokinetic (PK) set consisted of all participants who were enrolled and received the correct dose of study drug and had at least 1 measurable plasma concentration or amount of drug in the urine for TAK-954.

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: The safety set consisted of all participants who were enrolled and received the study drug.

6. Primary Endpoint

The registry lists the primary outcome as Cmax: Maximum Observed Plasma Concentration for TAK-954 (Total and Free), measured over Day 1 pre-infusion and at multiple time points (up to 96 hours) post-infusion.

The primary endpoint is Cmax, the maximum observed plasma concentration of TAK-954. It is reported as an endpoint for total and free drug, using nanograms per milliliter as the unit. Concentration was to be assessed before infusion on Day 1 and at multiple post-infusion time points up to 96 hours.

Cmax is used in pharmacokinetic studies to characterize the highest measured plasma concentration after administration. In general, comparing this measure across groups can help describe whether the concentration profile differs in relation to a characteristic such as hepatic function. It is a summary of observed concentrations, not a direct measure of clinical benefit, and it does not by itself describe the full concentration-time profile or the duration of exposure.

The registry record specifies geometric mean as the summary parameter and geometric coefficient of variation as the dispersion measure. In general, geometric summaries are useful for measurements that are positive and may vary multiplicatively rather than additively. The coefficient of variation provides a scale-relative description of variability around the geometric mean. These summaries can make concentration data easier to compare, but they do not replace the underlying group estimates or an uncertainty interval.

Numerical Cmax values, group-specific variability estimates, confidence intervals, and a reported comparison are not reported in the registry record. Thus, the endpoint and its intended summaries are identifiable, but the size and precision of any observed group differences are not.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

Pharmacokinetic analysis describes how drug concentrations change over time after administration. For this study, the listed primary measure is Cmax: the maximum observed plasma concentration of total and free TAK-954. The schedule included a pre-infusion measurement on Day 1 and multiple measurements up to 96 hours after infusion. In general, observations over time support characterization of a concentration profile; Cmax reduces that profile to its highest observed concentration. It does not, by itself, summarize every aspect of the profile.

Why use a geometric mean?

The registry record identifies the geometric mean as the summary parameter. In general, a geometric mean is appropriate for positive measurements when relative or multiplicative variation is a useful way to describe the data. It is based on the logarithmic scale: values are transformed, summarized, and then expressed on the original scale. This can make a central summary less dominated by particularly high values than an arithmetic mean, although the choice should match the data and analysis plan.

The geometric coefficient of variation is listed as the dispersion measure. In general, a coefficient of variation expresses variability relative to the scale of the measurements. A geometric version is associated with the logarithmic distribution of the measurements. It can help readers understand the spread of concentration values relative to a geometric mean, but it is not a confidence interval and does not, by itself, quantify the precision of a group comparison.

What does Cmax capture?

Cmax captures the highest measured concentration in the sampling schedule. The observed maximum may depend on the timing and density of sample collection, as well as on the concentration profile itself. The registry record states that sampling extended through multiple time points up to 96 hours, but the exact scheduled time points are not reported in the registry record. Cmax is useful as a defined summary, while other pharmacokinetic measures may answer different questions. The registry record’s primary outcome is specifically Cmax, so other measures should not be substituted for it.

What would uncertainty estimates add?

In general, a confidence interval describes a range of values compatible with the data and the statistical model at a stated confidence level. It helps distinguish a relatively precise estimate from one that is uncertain. An interval around a group estimate and an interval for a contrast answer different questions: the former concerns the group’s underlying summary, while the latter concerns the difference or ratio between groups, depending on the chosen scale. The numerical Cmax estimates and confidence intervals are not reported in the registry record, so neither the precision of group summaries nor the precision of comparisons can be assessed.

Concentration data are often analyzed on a logarithmic scale because their variation may be multiplicative. As a general statistical point, this can make distributions more suitable for methods that assume approximately symmetric errors on the analysis scale. Back-transformation then gives estimates on the original concentration scale. The registry record’s use of geometric means is consistent with describing concentrations multiplicatively, but the specific model, transformations, covariates, and comparison procedure are not reported in the registry record.

How does the design affect interpretation?

Non-randomized groups are not exchangeable by design. In general, randomization helps balance measured and unmeasured characteristics on average; a non-randomized comparison does not have that protection. Here, the groups are defined by hepatic-function status and include a healthy reference group. A difference in pharmacokinetic summaries could be associated with hepatic status, but the registry record does not report an adjusted analysis or enough participant-level detail to evaluate other explanations. The design is suitable for describing the specified cohorts, but causal attribution requires caution.

The trial is open-label, meaning masking is listed as none. For a measured concentration endpoint, open-label status does not automatically determine the measured value, but it remains part of the study context. The registry record does not report procedures for laboratory blinding or other safeguards, so those details should not be inferred.

The record’s sample-size assumptions describe an illustration based on an observed effect, with a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation; the effect to detect is a stated fraction of the observed effect. Time-to-event illustrations use total events, while other illustrations use participants per arm. These are planning illustrations, not observed power and not a statement of the trial’s original design. The trial itself is non-randomized and includes hepatic-function cohorts; equal allocation between two arms is an assumption for the illustration, not a description of the study groups. The numerical illustration outputs and the observed Cmax effect are not reported in the registry record.

10. Multiplicity, Missing Data and Analysis Populations

The registry record lists eight outcome measures and 12 analyses. It does not report a statistical analysis plan describing how the analyses were prioritized, whether multiplicity was addressed, or which comparisons were prespecified. When several outcomes or contrasts are examined, general statistical practice recognizes that the chance of at least one apparently notable result can increase. Adjustment procedures, hierarchical testing, or a clear distinction between confirmatory and exploratory analyses can help address that issue. None of those approaches should be attributed to this trial without documentation.

The primary endpoint is identified as Cmax for total and free TAK-954, but the record does not state how these outcomes were handled in relation to each other or to secondary outcomes. The registry record lists safety outcomes involving physical examination findings, electrocardiograms, vital signs, clinical laboratory changes, and treatment-emergent adverse events. The analysis methods for these outcomes are not reported in the registry record.

The pharmacokinetic set is defined as enrolled participants who received the correct dose and had at least one measurable plasma concentration or amount of drug in urine for TAK-954. The registry record does not report the number meeting this definition, the number excluded, or reasons for missing measurements. It also does not report how missing concentration values were handled, whether participants with incomplete sampling contributed to Cmax summaries, or whether any sensitivity analyses were performed.

These gaps limit assessment of selection into the analysis population and of the robustness of the estimates. In general, missingness can affect interpretation when the availability of measurements is related to participant characteristics or outcomes. Without a reported account of missing data and analysis decisions, the extent of any such effect cannot be assessed.

11. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

Deaths

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 0% reporting threshold.

Most frequent non-serious adverse event terms

The safety figures list healthy participants, participants with moderate hepatic impairment, and participants with severe hepatic impairment. For the healthy group, 8 participants were at risk for serious adverse events and 0 were affected; for the moderate impairment group, 10 were at risk and 0 were affected; for the severe impairment group, 7 were at risk and 0 were affected. Deaths are recorded as 0 in each of these listed groups. The registry record does not list a mild impairment group in the adverse-event entries.

For other adverse events, the record reports 2 affected among 8 at risk in the healthy group, 3 among 10 at risk in the moderate impairment group, and 1 among 7 at risk in the severe impairment group. These are counts of participants, not measures of event severity or duration. The record does not provide the event terms for these other events in the registry record. It lists no serious adverse-event terms.

These counts should be read as the registry’s reported safety observations for the listed groups. A count of 0 affected for serious adverse events means none were reported among participants at risk in that group; it does not establish that an event is impossible. The group sizes are limited, and the record does not provide information about follow-up completeness or a detailed safety analysis. The counts also do not provide a randomized comparison, because the study allocation was non-randomized. No safety conclusion about an unlisted group can be inferred from the entries shown in the registry record.

12. What the Result Does, and Does Not, Mean

This study is designed to examine the relationship between hepatic function and the pharmacokinetics of TAK-954 after a single intravenous dose. It identifies Cmax for total and free TAK-954 as the primary endpoint and specifies a geometric mean with geometric coefficient of variation. The registry record also describes the sampling window and the participant criteria for the pharmacokinetic set.

The numerical primary endpoint results are not reported in the registry record. Therefore, the record does not support a statement about the size or direction of a concentration difference between hepatic impairment groups and healthy participants, nor does it show how precisely any estimate was measured. Missing numerical results are not evidence of no difference, and the endpoint definition alone cannot establish whether groups had similar or different exposure.

The non-randomized design also limits causal interpretation. The hepatic-function groups were not created through random assignment, so any observed differences could be associated with other distinctions between the cohorts. This does not make the measurements uninformative; it means that conclusions should reflect the observational comparison and any documented analysis rather than treating group differences as an isolated effect of hepatic function.

The reported safety entries show zero participants with serious adverse events and zero deaths in the healthy, moderate impairment, and severe impairment groups listed. Other adverse events are recorded in those groups. The entries do not establish that all possible safety outcomes were absent, and no mild impairment safety count appears in the adverse-event group information included in the record.

In general, pharmacokinetic findings can describe concentrations and support further scientific interpretation, but they do not by themselves establish clinical benefit or provide treatment advice. The registry record does not report the primary numerical results, a full inferential analysis, or the rationale behind the study’s sample size. The warranted interpretation is therefore limited to the study’s design, endpoint definitions, analysis-population description, and reported safety counts.

13. Why This Trial Matters Statistically

Pharmacokinetic studies ask questions that differ from trials designed to compare clinical outcomes. This record focuses on the maximum observed concentration of TAK-954 after a single intravenous dose, across cohorts defined by hepatic function and a healthy reference group. That focus makes clear which measurement the study was intended to characterize, and the stated sampling window gives context for how the maximum was observed.

The statistical summaries matter because concentration measurements can vary on a multiplicative scale. Geometric means and geometric coefficients of variation are intended to describe central tendency and spread in that setting. Clear reporting of estimates and uncertainty is essential: without the numerical results, readers cannot assess the magnitude, precision, or pattern of differences across groups.

The design also illustrates why the label “comparison” does not imply randomization. Cohorts based on health characteristics can be compared descriptively, but non-randomized allocation does not balance other characteristics by design. Statistical adjustment might be relevant in some analyses, but the registry record does not report whether it was used. A careful reading separates the pharmacokinetic question from stronger causal claims that the design and available reporting do not establish.

Finally, this record shows the value of complete reporting. The endpoint, population definition, and safety counts provide useful context, while absent estimates, uncertainty intervals, missing-data details, and multiplicity methods leave key questions unresolved. This distinction is important for biostatisticians and clinical researchers: a registered study objective and an interpretable numerical result are not the same thing. The record supports understanding what was studied, but not a numerical conclusion about the primary pharmacokinetic outcome.

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 interpretation is that numerical results for the primary Cmax endpoint are not reported in the registry record. No group-specific geometric means, geometric coefficients of variation, or estimates comparing groups are available in the registry record used for this account. Without these values, the primary pharmacokinetic findings cannot be characterized in terms of direction, magnitude, or precision.

The non-randomized design is a further limitation for comparisons between hepatic-function cohorts. Differences may reflect hepatic function, other cohort characteristics, or both. The registry record does not report adjustment methods, participant characteristics beyond the group descriptions, or details needed to assess the comparability of cohorts. Open-label status is recorded, but procedures such as laboratory blinding are not reported in the registry record.

The registry record lists an enrollment of 25, but group-specific enrollment for all cohorts is not reported in the registry record. The pharmacokinetic population definition is stated, yet the number meeting it and the handling of missing or unmeasurable concentrations are not reported in the registry record. Exact sampling times within the stated period up to 96 hours are also not reported.

Although eight outcome measures and 12 analyses are listed, the statistical analysis plan, multiplicity approach, and analysis details are not reported in the registry record. The adverse-event information does not list a mild impairment group, so its safety counts cannot be described from these entries. These limitations constrain both the interpretation of the primary endpoint and the breadth of conclusions that can be drawn from the registry record.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: A Study to Evaluate the Effect of Hepatic Impairment on the Single Dose Pharmacokinetics (PK) of Intravenous TAK-954 — NCT03277274.
• Registry record last updated 2019-09-25; status last verified 2019-08.
• Results first posted 2019-09-25.
• 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.

18. Record Summary

The registry record describes NCT03277274, a completed Phase 1, non-randomized, open-label, sequential study sponsored by Takeda. Its purpose was to evaluate the effect of varying hepatic function on the pharmacokinetics of a single dose of intravenous TAK-954. Participants in mild, moderate, and severe hepatic impairment groups and a healthy group received TAK-954 0.2 mg as a 60-minute infusion once on Day 1. Enrollment is recorded as 25.

The primary endpoint is Cmax for total and free TAK-954, measured in nanograms per milliliter, with a geometric mean and geometric coefficient of variation specified. Sampling was scheduled before infusion and at multiple time points up to 96 hours after infusion. The registry record defines the pharmacokinetic set but does not report numerical primary outcome results in the information.

Safety entries report serious adverse event and death counts for the listed healthy, moderate impairment, and severe impairment groups. The record also lists other adverse events and multiple safety outcomes. Statistical analysis details, missing-data handling, and multiplicity methods are not reported in the registry record.