Aprepitant, Granisetron, & Dexamethasone in Preventing Nausea & Vomiting in Pts. Receiving Cyclophosphamide Before a Stem Cell Transplant: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Aprepitant, Granisetron, & Dexamethasone in Preventing Nausea & Vomiting in Pts. Receiving Cyclophosphamide Before a Stem Cell Transplant (NCT00293384), a na na study. The primary outcome is Proportion of Participants With Controlled Acute Vomiting.

2. Clinical Question

3. Trial Design

This was a completed pilot study, with phase recorded as NA. The registry lists a single-group model, allocation as NA, and masking as NONE. Its stated purpose was to evaluate aprepitant for prevention of nausea and vomiting secondary to high-dose cyclophosphamide given during peripheral hematopoietic progenitor cell mobilization before autologous transplantation. The regimen also included granisetron and dexamethasone, so the study describes the combined regimen rather than aprepitant in isolation.

The registry records enrollment of 40. That enrollment figure should not be assumed to be the denominator for every outcome. The primary outcome specifies an evaluable-for-response population, and the safety information uses its own at-risk denominators. The relationship between those analysis populations and the enrollment figure is not reported in the registry record.

The reported treatment schedule began with Kytril, dexamethasone, and aprepitant before cyclophosphamide on Day 1, followed by morning aprepitant on Days 2 & 3. Cyclophosphamide was administered intravenously over 90 - 120 minutes. The registry does not report a separate comparator regimen. Because there was no randomized comparison, outcome frequencies in this study cannot be interpreted as a direct comparative estimate against usual care or another antiemetic strategy.

The recorded start was 2004-10, primary completion was 2009-06, and overall status is COMPLETED. The sponsor is Barbara Ann Karmanos Cancer Institute. Further operational details, including the recruitment setting, eligibility rules, and the basis for selecting the enrollment target, are not reported in the registry record.

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

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: Evaluable for response

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: Patients who received all doses of the study drug were considered evaluable patients.

6. Primary Endpoint

The registry lists the primary outcome as Proportion of Participants With Controlled Acute Vomiting, measured over at 0-24 hours.

The primary endpoint is the proportion of participants with controlled acute vomiting at 0-24 hours. The registry defines control as having no episodes of vomiting and using no rescue medication during the first 24 hours after cyclophosphamide administration. It identifies the analysis population as evaluable for response and gives the outcome unit as participants.

This kind of binary endpoint classifies each evaluable participant according to whether the stated control definition was met. It combines vomiting and rescue-medication use: a participant must satisfy both parts of the definition to count as controlled. It is therefore not a measure of vomiting episodes alone, and it does not describe delayed vomiting or other symptoms beyond the stated acute period.

As a general statistical point, a clearly defined acute endpoint can make the outcome easier to interpret because the observation window and event criteria are specified. However, interpretation depends on the denominator and the rules for determining evaluability and handling incomplete observations. Those details are not reported in the registry record. The primary endpoint result itself is also not reported in the registry record, so no observed frequency, uncertainty interval, or conclusion about the regimen's performance can be drawn from the endpoint description alone.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What does the endpoint measure? The primary outcome is binary at the participant level: the registry counts participants with controlled acute vomiting. The definition requires no vomiting episodes and no rescue medication during the first 24 hours after cyclophosphamide. This is a composite rule for classifying control, rather than a count of episodes or a measure of symptom intensity. The listed unit is participants, and the population is evaluable for response. The number meeting the endpoint is not reported in the registry record.

As a general statistical point, binary outcomes can be summarized as counts and proportions. A proportion describes the observed frequency in the defined analysis population; it does not, by itself, indicate how uncertain that frequency is. A confidence interval is a range of values compatible with the observed data under a specified statistical method. It communicates sampling uncertainty, not a guarantee that the underlying value lies in the interval. No primary endpoint estimate or confidence interval is reported in the registry record.

What does the design allow? The study is recorded as single-group, with allocation listed as NA and masking as NONE. There is no randomized comparator identified in the registry record. As a general statistical point, a single-group study can describe outcomes among those receiving a regimen, but it cannot directly estimate a randomized treatment contrast. Changes or outcomes could reflect factors beyond the regimen, and this design cannot separate the effects of aprepitant, granisetron, and dexamethasone. The record's treatment schedule describes the drugs together with cyclophosphamide, which is the treatment context for the endpoint.

The sample-size assumptions recorded for planning describe an illustration computed from an observed effect, with two-sided significance level 0.05, equal allocation between two arms, and a normal approximation. The assumed effect to detect is a stated fraction of the observed effect. These are planning assumptions, not a description of the single-group trial's allocation. Any resulting sample-size figures are planning illustrations, not observed power. The registry record does not report the trial's own sample-size justification or a statistical design based on these assumptions.

As a general statistical point, a planning calculation asks how many participants might be needed under specified assumptions to detect a chosen effect at a chosen significance level. Its answer depends on those assumptions, including the comparison, allocation, outcome variability, and effect size. It does not show that a completed study had a particular probability of detecting an effect after observing its results. In this case, the stated illustration uses a two-arm equal-allocation framework, whereas the study record describes a single-group model. The record does not report the observed primary endpoint effect needed to assess the assumptions or a trial-specific sample-size calculation.

Why do denominators matter? Enrollment is recorded as 40, while the primary outcome population is described as evaluable for response and safety reporting gives 35 at risk. These are not interchangeable descriptions of the analysis population. A denominator identifies who contributed to a particular estimate; if participants are excluded or lack outcome information, the resulting estimate can depend on how that occurred. The criteria for evaluability, the reasons for any difference between denominators, and the handling of missing outcomes are not reported in the registry record.

As a general statistical point, missing outcomes can affect interpretation when the probability of missingness is related to participants' health or outcomes. Analysts may use different methods depending on why measurements are unavailable and what assumptions are defensible. No missing-data method is reported in the registry record. It is therefore not possible to determine whether the primary endpoint analysis included all enrolled participants, only those with recorded response status, or another defined subset beyond the stated evaluable-for-response population.

How should safety counts be read? The registry reports 10 participants affected by serious adverse events among 35 at risk, and 33 affected by other adverse events among 35 at risk. It also lists serious-event terms with percentages. As a general statistical point, these are descriptive event summaries. Their interpretation depends on definitions, follow-up, ascertainment, and whether individuals can experience or be counted under multiple terms. The registry does not report those details here, nor does it report a comparative safety analysis. Event percentages should not be read as causal effects of an individual drug.

The record identifies four outcome measures and three analyses, but does not give enough information in the recorded details to reconstruct the statistical models, test procedures, or adjustment choices for each analysis. The primary result, confidence intervals, and analysis-specific methods are not reported in the registry record. The sample-size assumptions should not be mistaken for the actual analysis plan. In a study without a concurrent comparator, statements about treatment differences or statistical significance between randomized groups would not describe the design recorded for this trial.

10. Exact Estimates for Each Arm

No two-arm comparison is shown for this trial, but each arm's result can still be summarized with exact interval estimates computed from the posted counts. The Clopper-Pearson interval is exact and conservative; the Wilson interval is a common closer-to-nominal alternative; the Bayesian credible interval uses a uniform Beta(1, 1) prior. For small groups the three can differ noticeably.

R code and output

arm    <- c("Aprepitant, Dexamethasone, Cytoxan & Kytril")
n      <- c(35)
events <- c(20)
for (i in seq_along(n)) {
  ci <- binom.test(events[i], n[i])$conf.int          # Clopper-Pearson exact interval
  cr <- qbeta(c(0.025, 0.975), 1 + events[i], 1 + n[i] - events[i])   # Bayesian, uniform Beta(1,1) prior
  wi <- (function(x, n) { p <- x / n; z <- qnorm(0.975); d <- 1 + z^2 / n
    c((p + z^2 / (2 * n) - z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d, (p + z^2 / (2 * n) + z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d) })(events[i], n[i])
  cat(sprintf("ARM|%s|%d|%d|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f\n", arm[i], n[i], events[i], 100 * events[i] / n[i],
              100 * ci[1], 100 * ci[2], 100 * wi[1], 100 * wi[2], 100 * cr[1], 100 * cr[2]))
}

ARM  Aprepitant, Dexamethasone, Cytoxan & Kytril  35  20  57.1  39.4  73.7  40.9  72.0  40.8  72.1

11. Multiplicity, Missing Data and Analysis Populations

The registry identifies the primary outcome as controlled acute vomiting at 0-24 hours and lists delayed vomiting controlled and toxicity Grade 3, 4, or 5 among the secondary outcomes. It records four outcome measures and three analyses. The result values for these outcomes and the relationship between the listed analyses and outcome measures are not reported in the registry record.

Multiplicity arises when several outcomes or statistical tests are considered. As a general statistical point, testing multiple outcomes can increase the chance that at least one result appears notable by chance, unless the analysis plan accounts for that possibility. The registry does not report whether multiplicity was addressed, which outcome was treated as confirmatory for analysis, or whether any secondary outcomes were exploratory. No multiplicity adjustment method is reported in the registry record.

The primary outcome population is described as evaluable for response. The eligibility rules for that population, the number with missing primary outcome data, reasons for missingness, and methods used to address missing data are not reported in the registry record. Enrollment is recorded as 40, while the safety summaries use at-risk denominators of 35. The record does not explain the relationship between these counts or whether the same participants contributed to each outcome analysis.

As a general statistical point, missing-data handling and analysis-population definitions can affect both the estimated outcome frequency and its uncertainty. Without the relevant rules and participant flow, the reported enrollment cannot be treated as the endpoint denominator. The record also does not report an intention-to-treat analysis, a per-protocol analysis, or a sensitivity analysis; their use should not be assumed.

12. 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 5% reporting threshold.

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: febrile neutropenia (17.1%), vomiting (5.7%), infection (5.7%), diarrhea (2.9%), pain (2.9%).

The registry reports serious adverse events for the regimen group as 10 participants affected among 35 at risk. It reports other adverse events as 33 participants affected among 35 at risk. These are distinct registry categories, and the record does not describe how event collection or attribution was performed. The at-risk denominator is the relevant context for reading each count; it should not be replaced with the enrollment figure.

The listed serious adverse event terms and percentages are febrile neutropenia, 17.1%; vomiting, 5.7%; infection, 5.7%; diarrhea, 2.9%; pain, 2.9%; and musculokeletal pain, 2.9%. The record does not say whether these categories overlap, so they should not be added or interpreted as mutually exclusive participant groups. It also does not report event timing, duration, severity details beyond the serious classification, or causal attribution to a particular drug. Deaths are not reported in the registry record.

As a general statistical point, adverse-event summaries describe observed reports under the specified study conditions. Without a comparator, they do not quantify excess risk attributable to the regimen. The safety figures should be read as descriptive counts and percentages from this single-group study, not as estimates of comparative safety.

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

The registry describes a pilot study of aprepitant given with granisetron and dexamethasone around high-dose cyclophosphamide for peripheral hematopoietic progenitor cell mobilization before autologous transplantation. The primary question concerns controlled acute vomiting at 0-24 hours, with control defined as no vomiting episodes and no rescue medication during the first 24 hours after cyclophosphamide. This description clarifies what the study intended to assess.

The primary endpoint result is not reported in the registry record. Consequently, the reported information does not establish how many evaluable participants met the endpoint, the corresponding observed frequency, or the precision of that estimate. The outcome definition alone is not evidence that the regimen achieved a particular level of control.

The study is recorded as single-group, without a concurrent randomized comparator. Its design can provide descriptive information about outcomes among participants receiving the combined regimen, but cannot show a direct treatment difference against an alternative. Because the drugs were administered as a combination in the cyclophosphamide setting, the study also cannot identify the separate contribution of each antiemetic drug from the design details recorded.

The safety record includes 10 participants with serious adverse events among 35 at risk, and 33 participants with other adverse events among 35 at risk. The record also lists several serious event terms and percentages. These figures describe reported events in the study; they do not establish that any event was caused by a particular drug, and they do not provide a comparative safety estimate.

As a general statistical point, estimates are most useful when their analysis population, outcome definition, missing-data handling, and uncertainty are clear. The evaluable-for-response criteria, primary outcome estimate, uncertainty interval, and missing-data methods are not reported in the registry record. The findings that can be described are therefore limited to the study question, the stated regimen and design, and the reported safety counts. No medical recommendation follows from these registry entries.

14. Why This Trial Matters Statistically

This trial is statistically notable for the distinction between a treatment question and the evidence its design can provide. The registry states a question about prevention of nausea and vomiting, but records a single-group model without a concurrent randomized comparator. That makes the interpretation descriptive: outcomes would characterize participants treated in the study, rather than estimate a randomized difference between regimens.

The endpoint definition is also important. Controlled acute vomiting requires no vomiting episodes and no rescue medication during the first 24 hours after cyclophosphamide. A compound definition can capture a clinically relevant pattern of control, but it depends on consistent measurement of both components and clear handling of unavailable data. The primary result and the evaluability rules are not reported in the registry record, limiting interpretation of the endpoint.

The separate denominators used for enrollment, response evaluation, and safety reporting illustrate why population definitions matter. Enrollment is recorded as 40, the primary population is described as evaluable for response, and the safety summaries use 35 at risk. The registry does not explain the relationship among these figures. As a general statistical point, estimates with different denominators can answer different questions and should not be treated as interchangeable.

Finally, the record distinguishes descriptive safety reporting from comparative inference. Counts and percentages can make event reporting concrete, but without a comparison group and further information about event ascertainment and attribution, they do not measure excess risk. These design and reporting features are central to understanding what the study can contribute and what remains uncertain.

15. 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 primary limitation for interpreting the efficacy question is that the primary endpoint result is not reported in the registry record. The endpoint definition is available, but the number of evaluable participants meeting it, the estimated proportion, and its uncertainty are not reported. The criteria for being evaluable for response and the handling of missing outcome information are also not reported.

The recorded design is single-group, with allocation listed as NA and masking as NONE. No concurrent comparator is described, so the study does not provide a randomized comparison. The combined regimen includes aprepitant, granisetron, and dexamethasone alongside cyclophosphamide; the design cannot separate the contribution of each component.

Enrollment is recorded as 40, while the safety summaries give 35 at risk. The registry does not explain the relationship between these denominators, participant disposition, or whether the outcome populations overlap. The record also does not report the observation period or ascertainment details for adverse events, whether event categories can overlap, or causal attribution. Deaths are not reported in the registry record.

The registry lists four outcome measures and three analyses, but the analysis methods, multiplicity approach, and missing-data procedures are not reported. It also does not report the trial's sample-size justification or a trial-specific statistical plan. Planning assumptions recorded for an illustration use a two-arm equal-allocation framework, which does not describe the single-group study design; any planning figures are not observed power. These limitations restrict both the precision of interpretation and the comparisons that can be made.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Aprepitant, Granisetron, & Dexamethasone in Preventing Nausea & Vomiting in Pts. Receiving Cyclophosphamide Before a Stem Cell Transplant — NCT00293384.
• Registry record last updated 2016-03-15; status last verified 2016-02.
• Results first posted 2014-10-03.
• 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.

19. Record Summary

The registry record describes a completed pilot study of aprepitant with granisetron and dexamethasone for nausea and vomiting associated with high-dose cyclophosphamide before autologous transplantation. The study is recorded as single-group, with phase NA, allocation NA, and masking NONE. Enrollment is recorded as 40. The sponsor is Barbara Ann Karmanos Cancer Institute; the recorded start is 2004-10 and primary completion is 2009-06.

The primary outcome is controlled acute vomiting at 0-24 hours among participants evaluable for response, defined as no vomiting episodes and no rescue medication during the first 24 hours after cyclophosphamide. The primary endpoint result is not reported in the registry record. Safety summaries report 10 participants with serious adverse events among 35 at risk and 33 with other adverse events among 35 at risk. The record does not provide a concurrent comparator or the additional analysis details needed for comparative interpretation.