Trial of Mesna to Prevent Doxorubicin-induced Plasma Protein Oxidation and Tumor Necrosis Factor Alpha (TNF-α) Release: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Trial of Mesna to Prevent Doxorubicin-induced Plasma Protein Oxidation and Tumor Necrosis Factor Alpha (TNF-α) Release (NCT01205503), a randomized phase 2 study. The primary outcome is TNF-alpha Levels in Patients Receiving Doxorubicin Containing Chemotherapy.

2. Clinical Question

The study's rationale concerns chemical changes in blood after doxorubicin. The brief summary says the researchers believed these changes might contribute to “cloudy thinking” or “chemobrain” reported by some people receiving chemotherapy. That proposed connection is the motivation described in the record, not a result established by the listed endpoint.

The primary endpoint is TNF-alpha, a blood measure, rather than a direct measure of thinking or cognitive symptoms. The listed secondary outcomes also concern blood markers: protein carbonyl, plasma HNE, troponin, and B-type natriuretic peptide. Whether participants' cognitive symptoms were assessed is not reported in the registry record. Consequently, the listed outcomes address changes in biomarkers, not whether mesna changes cognitive experience.

3. Trial Design

The registry identifies this as a completed phase 2 trial with randomized allocation, double masking, and a crossover model. Enrollment was 32. The listed conditions are breast cancer and non-Hodgkin's lymphoma. The record gives a start date of 2010-09 and a primary completion date of 2012-08.

The two treatment sequences were cycle 1 saline followed by cycle 2 mesna, or cycle 1 mesna followed by cycle 2 saline. Both sequences involved doxorubicin-containing chemotherapy, with cyclophosphamide also described in the arm information. Mesna or saline was infused before and 3 hours after doxorubicin. The mesna dose and infusion duration are given in the arm descriptions, but the descriptions are truncated; additional regimen details are not reported in the registry record.

In a crossover design, participants receive more than one treatment condition in sequence, rather than being assigned to just one condition throughout. This can allow a within-participant comparison, but its interpretation depends on details such as the timing of measurements, possible carryover between treatment periods, and the analysis of period and sequence effects. Those protocol and analysis details are not reported in the registry record. The record identifies randomization and double masking but does not describe how the random sequence was generated, who was masked, or how masking was maintained.

The registry lists five outcome measures: the primary TNF-alpha measure and four secondary blood-marker outcomes. It does not describe a sample-size justification or specify whether the enrollment target was based on a formal power calculation. The study is marked completed, but that status alone does not indicate whether all enrolled participants completed both cycles or contributed data at every scheduled time point.

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.

First Intervention (1st Cycle)

Second Intervention (2nd Cycle)

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: All subjects that received treatment.

6. Primary Endpoint

The registry lists the primary outcome as TNF-alpha Levels in Patients Receiving Doxorubicin Containing Chemotherapy, measured over prior to and 3 hours post doxorubicin and between cycles 1 and 2.

The primary endpoint is TNF-alpha levels in patients receiving doxorubicin-containing chemotherapy. The registry gives the unit as log(pg/ml), identifies the summary as a geometric mean, and describes the dispersion as a 95% confidence interval. The timeframe refers to measurements before and 3 hours after doxorubicin and between cycles 1 and 2. The outcome description says TNF-alpha was measured at four time points for each group.

TNF-alpha is a blood marker relevant to the chemical changes motivating the study. Measuring it can describe whether marker levels vary across the chemotherapy schedule and treatment conditions. It is not, by itself, a direct assessment of cognitive symptoms or proof that a measured blood change causes such symptoms.

In general, a geometric mean summarizes measurements on a multiplicative scale and is often used when analysis is conducted on a logarithmic scale. A confidence interval describes uncertainty around an estimated quantity under the statistical method used; it is not a range containing a fixed proportion of individual participants' values. The registry record does not report the endpoint's numerical estimates or confidence limits, nor does it specify the exact contrast intended between treatment conditions. Therefore, the size and precision of any treatment-related difference cannot be assessed from the posted primary-outcome information.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What does the crossover design mean?

In general, a crossover trial assigns participants to treatment sequences so that participants receive more than one condition over time. This trial's two listed sequences place saline and mesna in opposite orders across cycle 1 and cycle 2. A participant may therefore serve as their own comparator for some contrasts, which can reduce the influence of stable differences between participants. That advantage depends on appropriate measurement and analysis, and does not remove uncertainty from time-varying factors.

In general, crossover interpretation also depends on whether an earlier treatment can affect measurements during a later period, whether treatment effects vary by period, and whether there are differences by sequence. The registry record does not report a washout plan, carryover assessment, period-effect analysis, or sequence-effect analysis. It is not possible to determine from the record whether or how those considerations were handled.

What does randomization and masking contribute?

Randomized allocation is intended, in general, to reduce systematic differences between treatment sequences at assignment. Double masking is intended to limit the influence of knowledge of assigned treatment on care or assessment. The registry identifies the trial as randomized and double-masked, but does not describe the randomization procedure, the people masked, or whether masking was assessed. These labels describe design features; they do not, on their own, demonstrate that bias was absent.

How should the endpoint summary be read?

The endpoint is stated in log(pg/ml), with a geometric mean and 95% confidence interval. In general, logarithmic measurement expresses values on a transformed scale, while a geometric mean summarizes values in a way that corresponds to averaging on that logarithmic scale and returning to the original scale. The confidence interval conveys statistical uncertainty around an estimate under the method used. It does not describe the spread of individual measurements, and it does not establish clinical importance.

The outcome description identifies four time points for each group. A treatment effect could be defined in several ways across repeated measurements, but the registry record does not give a single contrast or a numerical analysis result. The record lists one analysis, yet that count does not specify the statistical model, how repeated observations were handled, whether adjustment was made, or what hypothesis was tested. Those details are not reported in the registry record.

Why do multiple measurements matter?

In general, testing or estimating effects at multiple time points and across multiple outcomes raises a multiplicity issue. The more questions considered, the more important it is to distinguish the prespecified primary question from exploratory comparisons and to understand any adjustment or interpretation plan. The record describes one primary outcome with several time points and four secondary outcomes, but a multiplicity strategy is not reported in the registry record. It would be inappropriate to assume that all comparisons were prespecified or that any particular adjustment was used.

What do the planning illustrations mean?

The sample-size illustrations are planning calculations, not observed power. Their stated assumptions are a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation; the effect to detect is expressed as a stated fraction of the observed effect. In general, such illustrations show how a hypothetical detectable effect relates to assumptions about variability, allocation, and the chosen significance level. They do not establish that the trial had a particular probability of detecting an effect, and they are not a substitute for a prospective design justification.

The registry record does not report the trial's own sample-size justification, the effect size used in its planning, or whether the posted illustration assumptions match the original design. The enrollment of 32 should not be interpreted as proof that the trial was adequately powered for the primary endpoint. Any planning illustration should be understood as a conditional calculation, not a description of what the trial observed.

What can be concluded from the available statistical information?

The endpoint definition indicates the intended measurement and summary, but numerical estimates and confidence intervals are not reported in the registry record. Without those results, readers cannot assess the magnitude, direction, or precision of the primary comparison. They also cannot infer a null result from the absence of numerical estimates. General statistical principles can explain what the stated design and summaries mean, but they cannot fill in missing treatment-effect results or undocumented analysis choices.

10. Multiplicity, Missing Data and Analysis Populations

The primary outcome is described at four time points, and the registry also lists four secondary outcomes. The primary outcome is not reduced to one comparison in the posted record. Multiple time points and outcomes can correspond to multiple statistical questions, so interpretation ordinarily depends on knowing which comparisons were prespecified and how multiplicity was handled. A multiplicity plan is not reported in the registry record.

The record does not give numerical primary or secondary outcome results, confidence intervals, or a detailed analysis plan. It does not report how missing observations were handled, whether all randomized participants were included in each analysis, or how the analysis population was defined. Whether participants completed both treatment cycles or posted all scheduled measurements is also not reported in the registry record.

For a crossover study, the treatment sequence and period structure can matter when defining an analysis population and interpreting incomplete follow-up. The registry record does not describe methods for incomplete sequences, missing measurements, carryover, or period effects. It is therefore not possible to determine whether the analysis accounted for these issues.

In general, missing-data methods rely on assumptions about why observations are missing. If those assumptions and the analysis approach are not stated, readers cannot judge how sensitive an estimate might be to missingness. The record's enrollment and completed status do not reveal the number of participants contributing to each endpoint analysis. Those details are not reported in the registry record.

11. Safety Results

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

Other (non-serious) adverse events

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

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: non-cardiac chest pain (3.1%), mrsa positive infection in toe (3.1%), lung infection (3.1%), blood bilirubin increased (3.1%), white blood cell decreased (3.1%).

The registry reports serious adverse events for 32 participants at risk in the mesna group and 32 at risk in the saline group. One participant is listed as having a serious adverse event in each group. Other adverse events are listed for 29 participants at risk in the mesna group and 30 at risk in the saline group. These are counts as recorded, not estimates of a treatment effect.

The listed serious-event terms are non-cardiac chest pain, MRSA positive infection in toe, lung infection, blood bilirubin increased, and white blood cell decreased. Each term is reported with 3.1%. The record does not provide further event-level detail in the information available for interpretation, so these terms should not be assumed to represent a complete description of each participant's experience or to establish a treatment relationship.

Deaths are not reported in the registry record. That is different from evidence that no deaths occurred. The event counts also do not establish whether events were caused by mesna, saline, chemotherapy, or other factors. In general, adverse-event comparisons need context about definitions, follow-up, exposure, and completeness of reporting. Those details are not reported in the registry record, so the figures are best read as descriptive counts rather than as a causal comparison or a definitive safety assessment.

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

This record identifies a randomized, double-blind, phase 2 crossover study that compared mesna and saline in opposite treatment sequences alongside doxorubicin-containing chemotherapy. Its primary endpoint was TNF-alpha at four scheduled time points, summarized as a geometric mean with a 95% confidence interval. The registry record does not report numerical primary-outcome results, so it does not establish the direction, size, or precision of a difference between treatment conditions.

The outcome focus is biochemical. TNF-alpha and the listed secondary blood markers can address questions about measured blood chemistry, but they are not equivalent to direct evidence about cognition. The study rationale mentions possible “cloudy thinking” or “chemobrain,” but cognitive outcomes are not listed among the reported endpoints. Whether cognitive symptoms were assessed is not reported in the registry record.

The crossover design can support comparisons within participants in general, but interpretation depends on period, sequence, carryover, and missing-data considerations. The registry does not describe the methods used to address these issues. Likewise, the presence of multiple outcome measures and time points makes the analysis plan relevant, but a multiplicity strategy is not reported.

The safety information lists serious and other adverse-event counts by group. These counts provide descriptive information, but the record does not establish event causality or report deaths. They should not be treated as a causal comparison or as a complete account of safety.

In general, a completed study record is not itself a statement that a treatment has or has not affected an outcome. The available registry information supports describing the study's question, design, endpoint, and listed adverse events. It does not support a conclusion about the primary biomarker effect or a conclusion about cognitive symptoms. Such conclusions would require outcome estimates and relevant analysis details that are not reported in the registry record.

13. Why This Trial Matters Statistically

This trial raises several statistical issues that are important when interpreting biomarker studies. First, it uses a crossover structure: participants are assigned to sequences and receive mesna and saline across different cycles. This design can make within-participant comparisons informative, but only when period, sequence, carryover, and incomplete follow-up are appropriately considered. Those analysis details are not reported in the registry record.

Second, the primary outcome is repeated across four time points. A result at one time point may not answer the same question as an overall treatment contrast across time. The registry describes the measurement schedule but does not report a single numerical comparison or a strategy for interpreting multiple time points. That limits what can be concluded from the endpoint description alone.

Third, the trial has one primary and four secondary biomarker outcomes. In general, interpreting multiple comparisons calls for clarity about which analyses were primary and how multiplicity was handled. The record identifies the outcomes but does not report such a plan or numerical results.

Finally, biomarker changes and patient-experienced outcomes answer different questions. The rationale invokes possible cognitive effects, whereas the listed outcomes measure blood markers. Distinguishing a measured biochemical response from a clinical or cognitive outcome is essential: one cannot be substituted for the other without evidence. In this case, the registry record supplies enough design information to identify that distinction, but not enough outcome information to quantify the primary biomarker result.

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 registry record leaves important details unavailable for interpreting this specific trial. It does not report numerical results for the primary TNF-alpha endpoint or the listed secondary outcomes. As a result, the magnitude and precision of any biomarker differences cannot be assessed. The primary outcome is described at four time points but is not reduced to one comparison.

The arm descriptions are truncated, and additional regimen details are not reported in the registry record. The record identifies the study as randomized, double-masked, and crossover, but does not explain the randomization procedure, who was masked, the timing between cycles, or how period and carryover effects were addressed. It also does not give the statistical model or define the analysis population.

Participant flow and missing-data handling are not reported. The enrollment count does not establish how many participants completed both cycles or contributed to each outcome analysis. The registry also does not report a trial-specific sample-size justification, or a multiplicity plan for the repeated primary measurements and secondary outcomes.

The study rationale refers to possible cognitive effects, but cognition is not among the listed outcomes. Whether cognitive symptoms were evaluated is not reported in the registry record. The adverse-event information is descriptive and does not establish causality; deaths are not reported in the registry record. Together, these limitations restrict conclusions to the design and event counts that are explicitly recorded, without allowing a quantitative assessment of the primary treatment comparison.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Trial of Mesna to Prevent Doxorubicin-induced Plasma Protein Oxidation and Tumor Necrosis Factor Alpha (TNF-α) Release — NCT01205503.
• Registry record last updated 2016-02-24; status last verified 2016-01.
• Results first posted 2016-02-24.
• 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 identifies NCT01205503 as a completed phase 2 randomized, double-blind crossover trial with enrollment of 32. The listed conditions are breast cancer and non-Hodgkin's lymphoma. Participants were assigned to sequences using mesna and saline across cycles 1 and 2 alongside doxorubicin-containing chemotherapy.

The primary outcome was TNF-alpha measured at four time points, with a geometric mean and 95% confidence interval specified. Secondary outcomes concerned protein carbonyl, plasma HNE, troponin, and B-type natriuretic peptide. Numerical outcome results and detailed analysis methods are not reported in the registry record.

Adverse-event listings include one participant with a serious event in each group and other adverse events in 29 mesna-group and 30 saline-group participants. Deaths are not reported in the registry record. These listings are descriptive and do not establish causality.