Oral Ifetroban to Treat Aspirin Exacerbated Respiratory Disease (AERD): Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Oral Ifetroban to Treat Aspirin Exacerbated Respiratory Disease (AERD) (NCT03028350), a randomized phase 2 study. The primary outcome is Change From Baseline in Sinonasal Outcome Test-22 Score.

2. Clinical Question

3. Trial Design

This was a phase 2, multicenter, double-blind, randomized, placebo-controlled trial with a parallel-group design. The registry identifies masking as quadruple. Participants were assigned to oral ifetroban or oral placebo, with each capsule taken daily for 8 weeks. The trial status is completed. Cumberland Pharmaceuticals is listed as the sponsor.

The registry lists enrollment of 54. The primary endpoint summaries include 22 participants in the ifetroban group and 29 in the placebo group. The primary-outcome population description says that participants needed SNOT-22 measurements at both baseline and 8 weeks. It also reports that three participants treated with ifetroban lacked measurements at both time points and were not analyzed for this outcome. The record does not describe the handling of any other missing measurements in detail.

The recorded study start date is 2017-07-17, and the primary completion date is 2023-04-25. Those dates mark the registry’s recorded study milestones; the record does not give a detailed account of recruitment pace or the reasons for the interval between them. The original protocol’s planned sample size, design assumptions, and statistical analysis plan are not reported in the registry record. In particular, the registry does not establish whether the enrollment target was based on a particular expected SNOT-22 effect or variance.

Randomization and masking describe important design features, but the record does not report the allocation ratio, how the random sequence was generated, or which specific roles were included in quadruple masking. The statistical interpretation is therefore limited to the design features and outcome summaries recorded, rather than assumptions about implementation details that are not reported.

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

Analysis population for the primary outcome, as defined in the registry: All subjects enrolled with SNOT-22 measurements at both baseline and 8 weeks were included. Three enrolled subjects treated with ifetroban did not have SNOT-22 measurements for both timepoints and therefore were not analyzed for this outcome.

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.

6. Primary Endpoint

The registry lists the primary outcome as Change From Baseline in Sinonasal Outcome Test-22 Score, measured over Baseline and 8 weeks.

The primary endpoint was change from baseline in SNOT-22 score, assessed at baseline and 8 weeks. SNOT-22 is a questionnaire-based scale concerning the presence and severity of symptoms and outcomes of rhinosinusitis. Its range runs from a minimum score of 0 to a maximum score of 110, with higher scores indicating worse symptoms and/or outcomes.

Change scores describe how a participant’s score at follow-up differs from their baseline score. In this trial, the reported group means are negative in both arms, indicating that the average recorded score decreased over the study period in each group. A difference between the groups’ average changes is the primary comparison; it is not the same as comparing their final scores alone. The posted mean difference is defined by the ifetroban change relative to the placebo change.

General: a patient-reported outcome can capture symptoms and effects that may not be represented by a physiological measurement alone. A baseline-to-follow-up change measure can also account for where participants started, although interpretation depends on how the analysis handles missing observations and other design features. The registry record does not report a threshold for interpreting the clinical importance of a particular SNOT-22 change. The scale description and group averages therefore support a statistical reading of the endpoint, but not a claim about what magnitude of change would be important to an individual participant.

7. Results Posted in the Registry

• Ifetroban Oral Capsule: mean -6.70 versus -13.70 on control; difference 7.00 (95% CI -2.83 to 16.83), standardized effect d = 0.37; z-test p = 0.163.

8. Secondary Efficacy Endpoints

The registry also posts results for secondary outcomes. For each outcome below, the endpoint type, the test applied to the posted summary statistics, the result and its interpretation are given in turn. Secondary endpoints are usually not adjusted for multiple testing, so they support rather than confirm the primary finding.

Change From Baseline in Asthma Control Questionnaire -7 Score

• Endpoint type: Continuous: a mean value per participant, compared as a difference in means.
• Test: Unadjusted two-sample z-test for the difference in means, using the posted standard deviations.
• Result:
  • Ifetroban Oral Capsule: mean 0.30 versus -0.20 on control; difference 0.50 (95% CI -0.33 to 1.33), standardized effect d = 0.42; z-test p = 0.240.
• Interpretation:
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between Ifetroban Oral Capsule and the control. The interval gives the range of effects that remain compatible with the data.

Change From Baseline in Total Nasal Symptom Score (Morning)

• Endpoint type: Continuous: a mean value per participant, compared as a difference in means.
• Test: Unadjusted two-sample z-test for the difference in means, using the posted standard deviations.
• Result:
  • Ifetroban Oral Capsule: mean -1.28 versus -2.57 on control; difference 1.29 (95% CI -0.27 to 2.85), standardized effect d = 0.51; z-test p = 0.106.
• Interpretation:
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between Ifetroban Oral Capsule and the control. The interval gives the range of effects that remain compatible with the data.

Change From Baseline in Forced Expiratory Volume in 1 Second (FEV1)

• Endpoint type: Continuous: a mean value per participant, compared as a difference in means.
• Test: Unadjusted two-sample z-test for the difference in means, using the posted standard deviations.
• Result:
  • Ifetroban Oral Capsule: mean 0.01 versus 0.00 on control; difference 0.01 (95% CI -0.21 to 0.22), standardized effect d = 0.02; z-test p = 0.957.
• Interpretation:
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between Ifetroban Oral Capsule and the control. The interval gives the range of effects that remain compatible with the data.

The registry lists six secondary outcomes, including asthma control, morning and afternoon/evening nasal symptoms, lung function, peak nasal inspiratory flow, and fractional exhaled nitric oxide. Detailed numerical comparisons are posted for three of them: asthma control questionnaire score, morning total nasal symptom score, and FEV1. Results for the other listed secondary outcomes are not reported in the registry record.

Across the posted secondary measures, the mean differences are not all in the same direction or of the same scale, and their confidence intervals are broad relative to the estimates. This is a reminder that the secondary outcomes represent different constructs and measurement units; their numerical differences cannot be compared directly as if they measured one common quantity. The secondary summaries do not supply a consistent basis for overturning or confirming the primary SNOT-22 result.

The secondary outcomes can add context to the primary endpoint because they assess related symptoms and a physiological measure over the same baseline-to-8-week period. However, they are not substitutes for the prespecified primary outcome. The primary comparison itself is uncertain, and the secondary analyses are also based on limited endpoint-specific participant counts. The registry does not report a unified analysis of these measures or a model that combines their evidence.

Unadjusted secondary results carry less weight when several outcomes are examined. General: multiple statistical tests create more opportunities for apparently unusual results to arise by chance, even when none of the underlying effects is real. A multiplicity strategy can control or otherwise address this issue, but the registry record does not report whether one was planned or used. No reported secondary analyses are listed in the record, so interpretation rests on the posted summary comparisons rather than a described sponsor analysis. The secondary results are best treated as exploratory context, not independent confirmation of a primary finding.

Secondary outcomes registered for this trial, for reference (only those above were recalculated):

• Change From Baseline in Asthma Control Questionnaire -7 Score
• Change From Baseline in Total Nasal Symptom Score (Morning)
• Change From Baseline in Forced Expiratory Volume in 1 Second (FEV1)
• Change From Baseline in Peak Nasal Inspiratory Flow Rate (PNIFR)
• Change From Baseline in Fractional Exhaled Nitric Oxide (FeNO)
• Change From Baseline in Total Nasal Symptom Score (Afternoon/Evening)

9. Statistical Interpretation

10. Statistical Methods Explained

The primary endpoint is continuous: it is measured on a numerical scale, and the registry summarizes it with a mean and standard deviation in each group. The ifetroban arm has a mean change of -6.7 with a standard deviation of 12.9 among 22 participants. The placebo arm has a mean change of -13.7 with a standard deviation of 22.6 among 29 participants. The mean describes the group’s average change; the standard deviation describes how spread out participant changes were around that average.

What does the mean difference represent?

The posted unadjusted mean difference is 7.0 units, calculated as the ifetroban group’s average change relative to the placebo group’s average change. This is a contrast between group averages, not a measure of the change experienced by any particular participant. Positive values indicate that the ifetroban group’s mean change is higher than the placebo group’s mean change on the signed scale. Since lower SNOT-22 scores indicate better symptom status, the sign should be interpreted alongside the negative average changes in both groups and the scale’s direction.

The comparison is a simple unadjusted recalculation from the posted summary statistics. It does not account for covariates, stratification, or other features of the randomization unless those are reflected in the summaries, and the registry does not report such adjusted analyses. The record lists no reported analyses for the secondary outcomes, and the number of analyses recorded is 0. A detailed sponsor analysis plan and model specification are not reported in the registry record.

What do the standard deviations and pooled standard deviation describe?

The arm-specific standard deviations show that observed changes varied among participants. The comparison also reports a pooled standard deviation of 19.06, which combines the within-group variability for the unadjusted comparison. General: variability matters because greater spread makes a group contrast harder to estimate precisely when sample sizes are limited. A standardized effect size expresses a mean contrast relative to a measure of variability; the posted standardized effect size for the primary endpoint is 0.367. It is a scale-free summary, not an additional clinical outcome or a direct probability of benefit.

General: a standard error describes the expected sampling variability of an estimate under a statistical model. The posted standard errors for the two group means are 2.75 for ifetroban and 4.197 for placebo. They help explain why the mean difference has uncertainty even though each group mean is reported as a single value. Standard errors are not measures of the spread of individual outcomes; that role belongs to the standard deviations.

How should the p-value be read?

The unadjusted p-value for the primary mean difference is 0.163. General: a p-value evaluates how unusual data at least as discrepant as those observed would be under a specified null hypothesis and its assumptions. It does not give the probability that the treatment has no effect, and it does not say how likely the observed estimate is to be replicated. A p-value also does not convey the range of plausible effect sizes; the confidence interval is more informative for that purpose.

The registry record does not report the trial’s own prespecified significance threshold or whether the primary test was adjusted for any other analyses. The sample-size planning illustration separately uses a two-sided significance level of 0.05, but that illustration is not evidence of the trial’s original analysis plan. The p-value should therefore be described as the posted unadjusted value, without assuming additional inferential procedures.

Why does over-dispersion matter in general?

General: over-dispersion means that observed variability is greater than a statistical model assumes. For a continuous outcome, an analysis that underestimates variability can make uncertainty appear too small; an analysis that reflects the observed variability can widen uncertainty. The posted standard deviations indicate substantial variation in SNOT-22 change, but the registry record does not identify an over-dispersion problem or report a model designed to address one. This concept is relevant as a general consideration, not as a finding about this trial.

Overall, the inferential quantities attached to the primary result are unadjusted summaries derived from the available arm-level statistics. Their interpretation depends on the measurement population, variability, and assumptions behind the calculation. The registry does not report enough detail to reconstruct all features of the sponsor’s planned analysis or to assess whether any alternative model was used in a separate report.

11. Confidence Intervals and Precision

The primary mean difference is 7.0 units, and its confidence interval runs from -2.834 to 16.83. General: a confidence interval expresses uncertainty around an estimate under the assumptions of the method used to construct it. It gives a range of values compatible with the data and method, rather than a guarantee that the true value lies within the interval or a probability statement about this particular result.

Because the interval includes zero, the posted estimate does not sharply distinguish a positive difference from no difference or a difference in the opposite direction. The span of the interval is also important: plausible contrasts cover materially different directions and magnitudes. The point estimate alone would conceal that uncertainty. The p-value of 0.163 is consistent with the interval’s inclusion of zero, but the interval conveys more about the range of estimates compatible with the data.

The group standard deviations, 12.9 for ifetroban and 22.6 for placebo, are large relative to the mean contrast. General: when outcome variability is substantial and the sample is limited, an estimate can remain imprecise even if the observed group means differ. The primary summaries are based on 22 ifetroban participants and 29 placebo participants with the endpoint measurements. Three enrolled participants treated with ifetroban were excluded from this endpoint analysis because paired measurements were unavailable. The registry record does not report a sensitivity analysis for missing outcomes.

The record does not state the confidence level associated with the interval in a way that permits additional assumptions to be made about it. Precision should therefore be described from the interval as posted, without attaching an unreported level or treating its boundaries as clinical thresholds. The interval is evidence of uncertainty in the estimated group contrast, not proof that all values inside it are equally likely or clinically equivalent.

12. Planning a Similar Trial: Sample Size

This is a planning illustration, not a re-evaluation of the original trial. It asks: if a new study wanted to detect a difference like the one observed, or a smaller one, how large would it need to be? It is deliberately not “observed power” of the finished trial, which is not a meaningful quantity.

The planning figures are participants per arm for continuous outcomes, including the primary SNOT-22 comparison. They are not total event counts. The illustration assumes a two-sided significance level of 0.05, equal allocation between the two arms, and a normal approximation. It uses the observed effect as its reference and considers detecting 100%, 75%, or 50% of that observed effect. The trial’s own original sample-size assumptions are not reported in the registry record.

The 80% power column gives the estimated number of participants per arm for a hypothetical study to have an 80% chance of detecting the specified effect under the planning assumptions, if that effect and the model assumptions are correct. The 90% power column represents a higher target chance of detection under the same assumptions and therefore calls for more participants per arm. These are planning illustrations, not observed power.

For the primary outcome, the planning illustration reports 117 participants per arm for 80% power and 156 participants per arm for 90% power when planning for 100% of the observed effect. For 75% of the observed effect, the corresponding figures are 207 and 277 participants per arm; for 50%, they are 466 and 624 participants per arm. These figures are scenario-dependent and should not be read as a recommendation for a future study without reviewing its design and assumptions.

Smaller effects are harder to distinguish from sampling variability, so detecting a smaller fraction of the observed effect requires more participants per arm in this illustration. The observed effect may itself be imprecise, particularly given the primary confidence interval and sample size. These calculations do not establish that the trial was underpowered or that its original design used these assumptions; the trial’s own sample-size justification is not reported in the registry record.

13. How the Sample Size Is Derived

Power is the probability that a study of a given size rejects the null hypothesis when a specific true effect exists. It depends on four things: the effect to detect, the variability of the outcome, the significance level (here a two-sided α of 0.05, so z_1−α/2 = 1.960) and the desired power (z_1−β = 0.842 for 80% and 1.282 for 90%).

Formula

n is the number of participants in each arm, Δ is the difference in means to detect and σ is the common standard deviation.

Worked calculation for this trial

1. Observed difference Δ = 7.000; pooled standard deviation σ = 19.057.
2. n = 2 × (1.96 + 0.842)² × 19.057² / 7.000² = 116.3, rounded up to 117 participants per arm for 80% power.

The smaller-effect rows in the table above repeat the same calculation with the effect multiplied by 0.75 and 0.5 (for ratios, applied to the logarithm of the ratio).

R code

alpha <- 0.05
z_a   <- qnorm(1 - alpha / 2)          # two-sided
delta <- 7                      # observed difference in means
sigma <- 19.0573195536893                     # pooled standard deviation
n_per_arm <- function(power, frac = 1) {
  ceiling(round(2 * (z_a + qnorm(power))^2 * sigma^2 / (delta * frac)^2, 6))
}
for (f in c(1, 0.75, 0.5))
  cat(sprintf("%3.0f%% of observed effect: n per arm = %s (80%% power), %s (90%% power)\n", 100 * f,
              format(n_per_arm(0.80, f), big.mark = ","), format(n_per_arm(0.90, f), big.mark = ",")))

# Check against R's built-in function (t-based, so very slightly larger)
cat("power.t.test:", round(power.t.test(delta = delta, sd = sigma, power = 0.80)$n, 1), "\n")

# Simulation: exact two-sample t-test using simulated means and variances
set.seed(3028350)
n    <- n_per_arm(0.80)
reps <- 20000
m_diff <- rnorm(reps, delta, sigma * sqrt(2 / n))             # difference in sample means
s2     <- sigma^2 * rchisq(reps, 2 * (n - 1)) / (2 * (n - 1))   # pooled sample variance
tstat  <- m_diff / sqrt(s2 * 2 / n)
cat(sprintf("Simulated power at n = %s per arm: %.3f (%d replicates)\n", format(n, big.mark = ","), mean(abs(tstat) > qt(0.975, 2 * (n - 1))), reps))

Output from running the code

100% of observed effect: n per arm = 117 (80% power), 156 (90% power)
 75% of observed effect: n per arm = 207 (80% power), 277 (90% power)
 50% of observed effect: n per arm = 466 (80% power), 624 (90% power)
power.t.test: 117.3 
Simulated power at n = 117 per arm: 0.794 (20000 replicates)

The simulation draws many sets of group means and variances at the planned sample size and counts how often the two-sample t-test rejects the null. It should land close to the target power; at very small required sample sizes it can fall below it, because the normal approximation is rough there.

14. Multiplicity, Missing Data and Analysis Populations

The registry lists a primary SNOT-22 outcome and six secondary outcomes. It reports detailed results for the primary endpoint and three secondary measures, while numerical results for the other listed secondary outcomes are not reported in the registry record. The record does not describe a hierarchy of testing, a familywise error procedure, or another strategy for handling multiplicity. It also does not report whether the secondary outcomes were intended to support confirmatory claims or to provide exploratory information.

General: when investigators test several outcomes, the chance of at least one apparently notable result can increase unless the analysis accounts for the number and structure of tests. This does not mean that every unadjusted result is false; it means that its evidential weight depends partly on the analysis plan and the other tests conducted. Because no multiplicity approach is reported, the posted secondary p-values should be read as unadjusted and should not be treated as confirmatory evidence on their own.

The primary population description requires SNOT-22 measurements at baseline and 8 weeks. It states that three participants treated with ifetroban did not have measurements for both time points and were not analyzed for this endpoint. The arm summaries report 22 ifetroban participants and 29 placebo participants. The registry record does not report why the measurements were unavailable, how missingness was handled beyond excluding those participants from this endpoint, or whether an imputation or sensitivity analysis was conducted.

Endpoint-specific sample sizes also differ across the posted secondary outcomes. This means the set of participants contributing to one measure is not necessarily the same as the set contributing to another. The record does not report a single analysis population definition that explains all these differences, nor does it describe whether all randomized participants were included in any other analysis. The exact analysis populations and missing-data methods beyond the primary outcome description are not reported in the registry record.

The original statistical analysis plan, any interim analyses, and the planned approach to missing data and multiplicity are not reported in the registry record. Without those details, it is not possible to determine whether the posted analyses followed a prespecified plan or whether additional analyses were conducted but not posted. These are limits on how strongly the endpoint results can be interpreted, not evidence that a particular analysis decision was made.

15. 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 3% reporting threshold.

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: diverticulitis (4.0%).

The safety figures count participants at risk and participants affected, separately for serious and other adverse events. For serious adverse events, 1 of 25 participants at risk in the ifetroban group was affected, compared with 0 of 29 in the placebo group. The registry reports 0 deaths in each group. For other adverse events, 7 of 25 participants at risk in the ifetroban group and 11 of 29 in the placebo group were affected.

The record lists Diverticulitis as the top serious adverse-event term, with 4.0%. The entry does not identify the group for this term or provide further event-level context. These counts describe what was recorded during the study; they do not establish that an event was caused by a study treatment. The registry record does not report enough detail to assess event timing, severity beyond the serious/non-serious classification, exposure-adjusted rates, or individual clinical circumstances.

General: safety counts should be interpreted in light of how many participants were observed and the duration of observation. With limited numbers, the absence of a recorded event in a group does not establish that the event cannot occur, and a difference in counts alone does not show causation. These results are descriptive registry figures, not a complete safety assessment.

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

The primary result is an estimate of the difference in average SNOT-22 change between participants assigned to ifetroban and placebo who had measurements at both baseline and 8 weeks. The estimate is 7.0 units, and the confidence interval ranges from -2.834 to 16.83. The interval includes zero and encompasses contrasts in both directions, so the posted data leave considerable uncertainty about the between-group difference.

Both groups had negative mean changes on a scale where higher scores indicate worse symptoms and/or outcomes. The observed means alone do not establish that the study intervention caused the changes. Participants may change over time for reasons not attributable to assigned treatment, and the group comparison is the relevant contrast for assessing whether average change differed between arms. Even that contrast remains imprecise in these data.

The registry record does not report a threshold for clinical importance on SNOT-22, so the statistical estimate cannot be translated into a judgment about whether a difference would matter to participants. Nor does the record report a detailed missing-data analysis, a prespecified multiplicity strategy, or the original analysis plan. Those omissions limit the strength of conclusions that can be drawn from the posted results.

The secondary results assess several additional outcomes, but they do not provide a clear, independently confirmed conclusion. Some listed outcomes lack posted numerical results, and the registry does not describe adjustment for multiple comparisons. Safety counts are descriptive and do not establish causality or rule out uncommon harms.

Accordingly, the registry results characterize a small phase 2 trial’s observed endpoint summaries and their uncertainty. They do not establish that ifetroban is effective or ineffective, and they do not determine what would happen in a different population, over a longer period, or under a different protocol. They are one set of results to be interpreted alongside the design limitations and the information not reported in the registry record.

17. Why This Trial Matters Statistically

This trial illustrates why an estimated difference, its uncertainty, and the analysis population need to be read together. The primary mean difference is 7.0 units, but its confidence interval extends from -2.834 to 16.83. Focusing only on the estimate would obscure the range of contrasts compatible with the data. The interval makes the limited precision visible.

The endpoint is a patient-reported scale with a stated direction: higher SNOT-22 scores indicate worse symptoms and/or outcomes. Reading the sign of a change or difference without the scale direction can lead to an incorrect interpretation. Here, both arm means are negative, but the positive between-group contrast means the ifetroban average change is higher than the placebo average change on that signed scale.

The trial also shows how endpoint populations can differ from overall enrollment. The primary outcome used participants with measurements at both time points, and the record explicitly notes three treated participants without paired SNOT-22 measurements. Other outcomes have their own endpoint-specific participant counts. Missing observations and analysis-population definitions affect how broadly a result can be generalized to everyone enrolled.

Finally, statistical evidence across multiple outcomes depends on the testing plan. The record lists several secondary measures, but does not report a multiplicity procedure or the original analysis plan. That absence matters when interpreting unadjusted findings: multiple outcomes can generate a mixed pattern that is difficult to treat as confirmatory. Transparent reporting of analysis choices and missing-data methods would help readers assess how robust the results are.

These considerations are central to reading clinical trial results generally. They do not replace subject-matter judgment, but they clarify what the posted statistical summaries can support and where uncertainty remains.

18. 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 endpoint analysis did not include every enrolled participant. The population description requires measurements at baseline and 8 weeks and identifies three ifetroban-treated participants who lacked both measurements and were not analyzed. Although arm-specific primary sample sizes are posted, the registry does not explain the reasons for missing measurements or report sensitivity analyses to assess their impact.

The primary comparison is unadjusted and based on summary statistics. The registry record does not report the original statistical analysis plan, the trial’s own sample-size justification, an adjusted model, or whether any interim analyses were conducted. It also does not report the planned handling of multiple endpoints. These gaps prevent a full assessment of how the posted comparisons relate to the trial’s prespecified analysis strategy.

Numerical results are not posted for all listed secondary outcomes. The available secondary results involve different measures and endpoint-specific sample sizes, and no multiplicity adjustment is described. Their pattern should therefore be interpreted cautiously rather than as a set of independent confirmatory findings.

The primary follow-up is at 8 weeks, so the posted endpoint does not describe longer-term outcomes. The record also does not report a clinical-importance threshold for SNOT-22 or individual participant-level response patterns. Group means and standard deviations cannot show the full distribution of changes or identify which participants experienced particular outcomes.

Finally, enrollment was 54, and the primary outcome summaries involve relatively limited group counts. The precision interval is broad, and its inclusion of zero reflects uncertainty in the estimated contrast. These limitations restrict conclusions from the registry record; they do not establish the direction or size of any effect beyond the posted estimates.

19. Related Tutorials

20. Related Statistical Calculators

21. Sources

• ClinicalTrials.gov: Oral Ifetroban to Treat Aspirin Exacerbated Respiratory Disease (AERD) — NCT03028350.
• Registry record last updated 2024-07-10; status last verified 2024-06.
• Results first posted 2024-06-28.
• 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.

22. Record Summary

NCT03028350 is a completed phase 2, multicenter, randomized, double-blind, placebo-controlled trial of oral ifetroban in symptomatic AERD. Participants received ifetroban 200 mg daily or placebo daily for 8 weeks. Enrollment was 54.

The primary outcome was change in SNOT-22 score from baseline to 8 weeks. Mean changes were -6.7 in the ifetroban group and -13.7 in the placebo group; the posted unadjusted mean difference was 7.0, with a confidence interval from -2.834 to 16.83 and an unadjusted p-value of 0.163. Three ifetroban-treated participants lacked measurements at both time points and were not analyzed for this endpoint.

Three secondary outcomes have numerical summaries, while results for other listed secondary measures are not reported in the registry record. The registry does not report the original sample-size justification, detailed analysis plan, missing-data sensitivity analyses, or multiplicity strategy. Safety counts include 1 serious adverse event in the ifetroban group and 0 in the placebo group; deaths were 0 in both groups.