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 Single Dose PK of IV Tedizolid Phosphate in Morbidly Obese and Non-Obese Adults (NCT02342418), a non-randomized phase 4 study. The primary outcome is This Outcome Measure is the Tedizolid Area Under the Concentration Time-curve From Time 0 to 72 Hours in Morbidly Obese Subjects and Matched Non-obese Subjects..
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT02342418 |
| Phase | Phase 4 |
| Condition | Obesity |
| Allocation | Non-Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 19 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Amit.Pai |
| Results posted | Yes |
2. Clinical Question
Population
Adults described as morbidly obese and non-obese. The morbidly obese group is defined as having BMI ≥ 40 kg/m2; the non-obese group is described as having BMI 18.5-29.9 kg/m2. The registry describes matching on age, sex, and ideal body weight.
Intervention
A single intravenous dose of tedizolid phosphate. The non-obese arm description states a dose of 200 mg through a peripheral intravenous catheter and says each group receives the dose.
Comparator
A matched group of non-obese adults is compared with the morbidly obese group. Allocation was nonrandomized, so the groups are not randomized treatment arms.
Primary question
How does tedizolid exposure, measured by area under the plasma concentration-time curve from time 0 to 72 hours, compare between morbidly obese adults and matched non-obese adults?
The study is a single-dose pharmacokinetic investigation rather than a trial designed to compare clinical outcomes. Its primary endpoint is an exposure measure: the area under the concentration-time curve (AUC) for tedizolid in plasma over the stated period. This can describe the overall concentration exposure during that interval, rather than focusing on only one measurement time.
The registry record describes matching by age, sex, and ideal body weight, with an age tolerance of ± 5 years and an ideal-body-weight tolerance of ± 4.6 kg. The record also gives ± 5 cm in height as an equivalent description of the ideal-body-weight tolerance. Matching is intended to make selected characteristics more comparable across groups, but it does not make the allocation randomized. Other differences between the groups may remain.
The clinical question is therefore limited to a pharmacokinetic comparison after one dose. Numerical primary-outcome results, including group values and a measure of uncertainty, are not reported in the registry record. The direction and precision of any observed AUC contrast cannot be described from this record.
3. Trial Design
This is a Phase 4, open-label, nonrandomized, parallel-group study of intravenous tedizolid phosphate. The registry lists enrollment as 19 and status as completed. The listed start and primary-completion dates are 2015-03 and 2015-09. The brief summary describes a single-dose pharmacokinetic study in 9 obese and 9 age-, sex-, and ideal-body-weight-matched non-obese subjects, while the safety record lists 9 participants at risk in the morbidly obese group and 10 in the non-obese group. The registry record does not explain the difference between these enrollment descriptions.
The morbidly obese group was to be recruited first. Each participant in that group was to be matched with a non-obese participant on age, sex, and ideal body weight. The arm description specifies BMI ≥ 40 kg/m2 for the morbidly obese group and BMI 18.5-29.9 kg/m2 for the non-obese group. It describes matching tolerances of ± 5 years for age and ± 4.6 kg for ideal body weight, with the latter also expressed as ± 5 cm in height.
The study is open label, with no masking, and uses a parallel rather than crossover model. The registry identifies tedizolid phosphate as the intervention and describes a single dose. The non-obese arm description specifies 200 mg through a peripheral intravenous catheter and states that each group receives the dose.
After dosing, the brief summary describes collection of 11 blood samples over 72 hours. This sampling schedule is consistent with assessing drug concentrations over time, but the actual concentration measurements and their analysis are not reported in the registry record. The record does not report the rationale for the planned enrollment, further operational details of matching, or a statistical analysis plan. The nonrandomized design means matching should be understood as a design feature, not as evidence that the groups were otherwise exchangeable.
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 | Morbidly Obese | Non-obese |
|---|---|---|
| STARTED | 9 | 10 |
| COMPLETED | 9 | 9 |
| NOT COMPLETED | 0 | 1 |
Reasons for not completing this period:
| Reason | Morbidly Obese | Non-obese |
|---|---|---|
| Adverse Event | 0 | 1 |
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.
| Characteristic | Unit | Morbidly Obese | Non-obese | Total |
|---|---|---|---|---|
| Participants analysed | 9 | 9 | 18 | |
| Age, Continuous | years | 38 (26 to 50) | 37 (24 to 46) | 37 (24 to 50) |
| Sex: Female, Male: Female | Participants | 7 | 7 | 14 |
| Sex: Female, Male: Male | Participants | 2 | 2 | 4 |
| Body Mass Index | kilogram per square meter | 43.5 (40.4 to 51.8) | 27.4 (25.4 to 29.1) | 36.1 (25.4 to 51.8) |
6. Primary Endpoint
The registry lists the primary outcome as This Outcome Measure is the Tedizolid Area Under the Concentration Time-curve From Time 0 to 72 Hours in Morbidly Obese Subjects and Matched Non-obese Subjects., measured over 12 months.
| Element | Registry entry |
|---|---|
| Result type | Median |
| Measure of spread | Full Range |
| Unit | hour*milligram/Liter |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is the area under the tedizolid plasma concentration-time curve from time 0 to 72 hours, compared between morbidly obese participants and matched non-obese participants. The registry gives the unit as hour*milligram/Liter and describes the endpoint as the amount of drug exposure over the specified concentration-time interval. It identifies the summary parameter as the median and the dispersion as the full range.
In general, an area under a concentration-time curve combines concentration measurements across a period of observation. It is used in pharmacokinetic studies because it represents exposure over time, rather than the concentration at a single sampling point. AUC is therefore relevant to a question about whether measured drug exposure differs between groups after dosing. It does not, by itself, describe a clinical outcome or establish the consequences of a concentration difference.
The registry’s primary-outcome timeframe is listed as 12 months, while the endpoint title and description specify the concentration-time interval from time 0 to 72 hours. The record does not explain this difference in timeframe labeling. The endpoint description is clear about the pharmacokinetic interval, but the registry record does not report the group medians, full ranges, an estimated contrast, or an uncertainty interval. Consequently, the numerical comparison and its precision cannot be assessed from the posted registry information.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The posted record identifies the intended comparison but does not report the numerical primary endpoint results. It names AUC from time 0 to 72 hours as the primary measure and specifies median and full-range summaries. Without the group medians and ranges, the observed exposure in either group cannot be stated. Without a reported contrast or uncertainty measure, the size, direction, and precision of a group difference cannot be evaluated.
This absence of numerical outcome values is central to interpretation. The record does not support a statement that exposure was higher, lower, or similar between groups. It also does not establish that a difference is absent: an unreported estimate is not evidence of equivalence. A conclusion about similarity would require a defined criterion for similarity and results precise enough to assess it; neither is reported in the registry record.
The planned matching on age, sex, and ideal body weight helps describe how the study sought to construct comparable groups. It does not remove the limits of nonrandomized allocation. Matching addresses only the named characteristics and does not ensure that all other factors are balanced. The registry record does not report adjusted analyses or enough information to assess whether any group contrast accounted for additional participant characteristics.
The sample-size planning illustration is described as based on the observed effect, with two-sided significance level 0.05, equal allocation, and a normal approximation. It considers detecting a stated fraction of the observed effect. However, the actual observed effect, fractions, and resulting planning counts are not reported in the registry record. Such planning counts, when available, would be design illustrations and not observed power or evidence about the result.
The safety information is separate from the primary pharmacokinetic outcome. The record lists no serious events among 9 participants at risk in the morbidly obese group and none among 10 at risk in the non-obese group. It lists no other events among the 9 morbidly obese participants and 1 other event among the 10 non-obese participants. These counts are descriptive; they do not establish that an event was or was not caused by the study drug. Death counts are not reported in the registry record.
Overall, the record gives useful design and endpoint definitions, but its posted results do not permit quantitative interpretation of the primary comparison. A pharmacokinetic estimate, its uncertainty, and the analysis details would be needed to assess how compatible the data are with different possible group contrasts.
9. Statistical Methods Explained
What does the endpoint measure?
Area under the concentration-time curve is a pharmacokinetic summary of drug concentration across a defined period. For this study, the stated interval runs from time 0 to 72 hours after a single intravenous dose. In general, integrating concentration over time captures more of the exposure profile than a measurement taken at one time point. The registry expresses the unit as hour*milligram/Liter and identifies the median and full range as the summary approach.
The endpoint is not a direct measure of a clinical benefit or harm. It describes drug exposure in plasma. The separate secondary outcome concerns maximum plasma concentration, which focuses on the highest measured concentration rather than cumulative exposure over the interval. Numerical results for either measure are not reported in the registry record.
Why use a median and full range?
In general, the median is the middle value when observations are ordered. It can describe the center of a distribution without being pulled as strongly by unusually high or low observations as a mean can be. The full range reports the lowest and highest observed values, so it communicates the span of the data but does not show how observations are distributed between those extremes.
A range alone is not a confidence interval. A confidence interval, in general, describes uncertainty around an estimated quantity under a statistical model and analysis procedure. No confidence interval for the primary comparison is reported in the registry record. Because the group medians and ranges are also not reported, neither the observed spread nor the uncertainty around the comparison can be assessed.
What does matching contribute?
The registry describes matching on age, sex, and ideal body weight. Matching seeks to align participants on specified characteristics before comparing outcomes. In this study, it is part of a nonrandomized design: the morbidly obese group was to be recruited first, and non-obese participants were to be matched to them. The approach can make the comparison more focused on the groups defined by obesity status for the characteristics used in matching, but it does not have the same properties as random allocation.
In general, nonrandomized comparisons may remain vulnerable to differences in characteristics that were not matched or measured. Matching also does not by itself specify how paired or matched observations were handled in an analysis. The registry record does not report the statistical procedure used for matching in the analysis, whether matching was retained in the endpoint analysis, or whether any covariate adjustment was performed.
What can be inferred from the design?
The parallel-group structure means participants are described in separate groups rather than receiving both group conditions in sequence. The open-label designation means masking is not reported as part of the study design. The pharmacokinetic outcome is based on serial blood sampling after a single dose; the brief summary describes 11 samples collected over 72 hours. These design features characterize how the study was set up, but they do not provide the missing outcome estimates.
Enrollment is listed as 19. The brief summary describes 9 participants in each group, whereas the safety record lists 9 at risk in the morbidly obese group and 10 at risk in the non-obese group. The registry record does not reconcile these counts. It also does not report an analysis population, participant flow, missing concentration data, or how incomplete sampling was handled.
What do the planning assumptions mean?
The record describes a planning illustration based on the observed effect. Its stated assumptions are a two-sided significance level of 0.05, equal allocation, and a normal approximation, with the target effect defined as a stated fraction of the observed effect. In general, these assumptions specify a hypothetical design calculation: how many participants per arm might be needed to detect a selected effect under the assumed model and error criterion.
The illustration is not an analysis of the trial’s observed evidence and does not represent observed power. Its interpretation would depend on the observed effect and the selected fraction, neither of which is reported in the registry record. The resulting planning counts are also not reported in the registry record. A sample-size illustration based on an observed estimate can be sensitive to the uncertainty in that estimate; it should not be read as a substitute for a prespecified design justification.
The record does not report the planned statistical test, a model for the concentration data, an approach to the matched structure, a confidence-interval method, or any interim analysis. These details cannot be inferred from the choice of median and full range. General statistical practice may use methods suited to skewed pharmacokinetic data, but the analysis actually used in this study is not reported in the registry record.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists 2 outcome measures and 2 analyses. The primary outcome is AUC from time 0 to 72 hours, and the secondary outcome is maximum plasma concentration. The registry record does not report whether the analysis plan controlled for multiplicity across these outcomes, specified a hierarchy, or adjusted significance criteria for multiple testing. Without that information, the role of any individual statistical test in a broader set of analyses cannot be determined.
The statistical analysis plan, including the planned tests and any interim analyses, is not reported in the registry record. The record also does not identify a prespecified primary analysis population, explain whether analyses followed the matched pairs, or state how covariates were handled. The total enrollment and safety denominators are documented, but participant flow for the pharmacokinetic endpoint is not described.
Missing data handling is not reported in the registry record. In general, incomplete concentration sampling can affect an exposure estimate, particularly when the missing measurements occur within the interval used to calculate AUC. That general concern does not establish that any samples were missing in this study; the record gives no account of missingness or its treatment.
The primary endpoint description specifies a 12-month timeframe, while its concentration-time definition specifies time 0 to 72 hours. The registry record does not explain the timeframe label. It also does not report numerical results for either outcome, so it is not possible to examine whether results were available for all planned outcomes or whether any analyses were omitted.
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 |
|---|---|---|---|
| Morbidly Obese | 0 | 9 | 0.0% |
| Non-obese | 0 | 10 | 0.0% |
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 |
|---|---|
| Morbidly Obese | 0 of 9 |
| Non-obese | 1 of 10 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Morbidly Obese | Non-obese |
|---|---|---|---|
| Intravascular Infiltration | Blood and lymphatic system disorders | 0 of 9 | 1 of 10 |
The safety record lists serious adverse events for 9 participants at risk in the morbidly obese group and 10 participants at risk in the non-obese group. It reports 0 serious events in each group. These are counts within the listed groups; the registry record does not provide further details about event definitions, duration of safety follow-up, or attribution to tedizolid.
For other adverse events, the record lists 0 affected participants among 9 at risk in the morbidly obese group and 1 among 10 at risk in the non-obese group. The term “other” distinguishes these entries from the serious-event counts, but the registry record does not provide the event term for the single reported event. The list of serious-event terms is empty.
Death counts are not reported in the registry record. The absence of a listed serious event should be read as a reported count of zero in the relevant group, not as proof that the treatment has no risk. Likewise, the one other event in the non-obese group does not establish a causal relationship. These small group counts are descriptive and do not provide a comparative safety estimate with reported uncertainty.
12. What the Result Does, and Does Not, Mean
This record establishes that a small, nonrandomized, open-label pharmacokinetic study was conducted to compare morbidly obese adults with matched non-obese adults after a single intravenous dose of tedizolid phosphate. It defines the main exposure measure as AUC from time 0 to 72 hours and identifies maximum plasma concentration as a secondary outcome. It also documents a plan to match participants on age, sex, and ideal body weight.
The record does not report numerical results for either pharmacokinetic outcome. Therefore, it cannot show the size or direction of the observed exposure contrast, how variable the measurements were, or how precisely the contrast was estimated. No conclusion about equivalent exposure, a meaningful difference, or the absence of a difference follows from the missing numerical results.
The design can inform what kind of comparison was intended, but it does not establish that obesity status alone explains any potential difference. Nonrandomized allocation can leave groups different in characteristics beyond those used for matching. The registry record does not report an adjusted analysis that would clarify how such differences were addressed.
The safety entries document zero serious events in both listed groups and one other event in the non-obese group, with none in the morbidly obese group. These counts do not establish causation or rule out uncommon harms. Death counts are not reported in the registry record, and the event description for the single other event is not given.
Thus, the record supports a description of the study question, design, endpoint, and limited event counts. It does not support a quantitative answer to the primary pharmacokinetic question. The observed AUC estimates, their uncertainty, and the analysis methods would be needed for a fuller statistical interpretation.
13. Why This Trial Matters Statistically
This study is statistically distinctive because it asks a focused pharmacokinetic question using a nonrandomized matched comparison. Rather than assigning participants to different interventions, it compares drug exposure after the same stated single-dose treatment across groups defined by obesity status. The central statistical task is to estimate how the concentration-time profile, particularly AUC over the specified interval, differs between those groups.
Matching on age, sex, and ideal body weight makes the intended comparison more explicit. It also highlights a key design principle: control of selected characteristics is not equivalent to randomization. The quality of interpretation depends on which characteristics were matched, how the matched structure entered the analysis, and whether other relevant differences were addressed. The registry record does not report the analysis details needed to evaluate these points.
Pharmacokinetic measures also illustrate why summary choice matters. AUC describes exposure over time, while maximum concentration summarizes a peak. These answer related but distinct questions about the concentration profile. Reporting medians and full ranges can describe the data’s center and span, but a comparative estimate with uncertainty is needed to judge the precision of a group contrast.
The registry record provides the endpoint definition but not the numerical endpoint results. This makes the distinction between a well-defined question and an answer especially important: readers can identify the comparison the investigators intended, but cannot determine the observed contrast from the posted information. The sample-size planning assumptions are described, yet the numerical planning outputs and observed effect are not reported. Those calculations cannot substitute for outcome estimates.
The record also illustrates the importance of consistent participant accounting. Enrollment is listed as 19, the brief summary describes 9 participants per group, and the safety record lists group denominators of 9 and 10. The registry does not reconcile these descriptions. Clear flow and analysis-population reporting would help readers connect the enrolled participants to each endpoint and safety summary.
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 AUC outcome are not reported in the registry record. The record gives no group medians, full ranges, estimated contrast, or uncertainty interval. Numerical results for the secondary maximum-concentration outcome are also not reported. Consequently, the pharmacokinetic comparison cannot be evaluated quantitatively.
The nonrandomized design limits causal interpretation. Matching was planned for age, sex, and ideal body weight, but the record does not report whether those matches were completed as planned or how the matched structure was incorporated into the analysis. It also does not report adjustment for other participant characteristics. Matching cannot be assumed to eliminate all sources of group difference.
Participant counts are not fully reconciled. Enrollment is listed as 19; the brief summary describes 9 obese and 9 non-obese participants; and the safety record lists 9 at risk in the morbidly obese group and 10 at risk in the non-obese group. The registry record does not explain this discrepancy or identify the population used for each pharmacokinetic analysis.
The analysis plan, missing-data approach, and handling of incomplete concentration sampling are not reported in the registry record. The record also does not describe the statistical method for estimating AUC, the method used for the group comparison, or any confidence-interval procedure. The primary endpoint timeframe is listed as 12 months even though its description defines a 0-to-72-hour concentration-time interval; this difference is not explained.
Safety information is limited to event counts, with no reported death counts and no term for the single other event. These gaps constrain interpretation of both efficacy-related pharmacokinetic findings and safety, without implying that unreported outcomes were absent.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Single Dose PK of IV Tedizolid Phosphate in Morbidly Obese and Non-Obese Adults — NCT02342418.
- Registry record last updated 2017-03-15; status last verified 2017-01.
- Results first posted 2017-03-15.
- 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 a completed Phase 4, open-label, nonrandomized, parallel-group study of single-dose intravenous tedizolid phosphate in morbidly obese and matched non-obese adults. It lists enrollment as 19 and describes matching on age, sex, and ideal body weight. The primary pharmacokinetic endpoint is AUC from time 0 to 72 hours; maximum plasma concentration is listed as a secondary outcome.
Numerical results for the pharmacokinetic outcomes and the analysis methods are not reported in the registry record. The safety record lists 0 serious events among 9 morbidly obese participants and 0 among 10 non-obese participants; other events are listed as 0 and 1, respectively. Death counts are not reported in the registry record. Enrollment descriptions differ across the record, and that difference is not explained.