Clarithromycin Mechanisms in Hypersomnia Syndromes: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Clarithromycin Mechanisms in Hypersomnia Syndromes (NCT04026958), a randomized phase 2 study. The primary outcome is Change in Epworth Sleepiness Scale (ESS) Score.

2. Clinical Question

The registry describes a Phase 2 randomized, double-masked, parallel trial. The question is about the difference between the arms in a self-reported measure of daytime sleepiness over the stated treatment period. It is not a comparison of whether an individual participant improved, nor does the group mean show how consistently participants responded.

The study description also names brain activity measured with magnetic resonance imaging, inflammation, gut bacteria, and cerebrospinal fluid as areas of interest for understanding mechanisms. Those aims provide context for the trial, but the primary outcome is the change in Epworth Sleepiness Scale score. The primary result therefore addresses a sleepiness measure, not the proposed biological mechanisms.

3. Trial Design

The registry identifies this as a Phase 2, randomized, double-masked, parallel-group trial sponsored by Emory University. It lists clarithromycin and placebo as the two drug interventions, with each assigned arm described as receiving its assigned treatment for 14 days. A parallel design compares participants in one arm with participants in the other over the study period; it is not described as a crossover design.

The registry enrollment is 83. Separately, the brief study description says the study would recruit 92 participants. These are different figures in the record: one is the stated enrollment and the other appears in the description of the planned recruitment. The registry status is completed. The listed start date is 2019-09-04 and the primary completion date is 2025-06-18.

The primary outcome is change in Epworth Sleepiness Scale score, with the timeframe stated as Day -1 and Day 14. The primary analysis population is described as participants who completed the scale during at least one study timepoint. The number of participants contributing to the posted primary outcome differs by arm, and the registry does not explain those analysis counts in further detail.

The record lists 25 outcome measures and 19 posted secondary outcomes. It does not report the original sample-size justification, the planned statistical analysis protocol, or interim analyses. Those details should not be inferred from the observed enrollment or from the planning illustrations based on observed effects.

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: This analysis includes participants who completed the ESS during at least one study timepoint.

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 in Epworth Sleepiness Scale (ESS) Score, measured over Day -1, Day 14.

The primary endpoint is change in Epworth Sleepiness Scale score between baseline, specified as Day -1, and Day 14. The scale asks participants to rate the likelihood of dozing in 8 scenarios, using a 4-point response scale from 0, meaning would never doze, to 3, meaning high chance of dozing. Its total score ranges from 0 to 24, with higher scores indicating a higher chance of falling asleep during daytime activities.

Change is defined as the baseline total score minus the Day 14 total score. Under that definition, a positive change means the average Day 14 score was lower than the average baseline score, which the registry describes as indicating less sleepiness. The endpoint is therefore oriented so that a positive within-arm change represents a decrease in the score over the study period.

A scale score is used to represent a participant-reported aspect of daytime sleepiness in a structured way. Comparing average changes between randomized arms can describe how the groups differed over the same timeframe. It does not, by itself, explain why any change occurred, establish how participants experienced other symptoms, or show the distribution of individual responses. The primary outcome is a mean change, not a measure of the proportion of participants whose score improved.

7. Results Posted in the Registry

• Clarithromycin: mean 1.70 versus 2.50 on control; difference -0.80 (95% CI -2.54 to 0.94), standardized effect d = -0.20; z-test p = 0.369.

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.

On-Treatment Sleep Duration

• 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:
  • Clarithromycin: mean 493.20 versus 479.90 on control; difference 13.30 (95% CI -28.43 to 55.03), standardized effect d = 0.19; z-test p = 0.532.
• Interpretation:
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between Clarithromycin and the control. The interval gives the range of effects that remain compatible with the data.

Change in Fatigue Severity Scale (FSS) 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:
  • Clarithromycin: mean 3.50 versus 3.50 on control; difference 0.00 (95% CI -4.38 to 4.38), standardized effect d = 0.00; z-test p = 1.000.
• Interpretation:
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between Clarithromycin and the control. The interval gives the range of effects that remain compatible with the data.

Change in Multidimensional Fatigue Inventory (MFI-20) 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:
  • Clarithromycin: mean 3.80 versus 6.60 on control; difference -2.80 (95% CI -8.37 to 2.77), standardized effect d = -0.22; z-test p = 0.325.
• Interpretation:
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between Clarithromycin and the control. The interval gives the range of effects that remain compatible with the data.

The registry lists a broad collection of secondary outcomes, including sleep duration, fatigue, sleep inertia, and inflammatory measures. The posted secondary summaries cover a subset of these outcomes and include on-treatment sleep duration, fatigue severity, and MFI-20 change. Their directions are not uniform: the sleep-duration estimate is positive, the fatigue severity mean difference is zero, and the MFI-20 estimate is negative for clarithromycin relative to placebo. These measures capture different constructs, so the pattern should not be collapsed into a single overall effect.

At a broad level, the secondary summaries do not remove the uncertainty in the primary comparison. They also do not provide a consistent pattern that independently resolves the primary result. The outcomes use their own scales, timeframes, and analysis counts, and some have confidence intervals spanning zero. The posted values are descriptive comparisons, not a substitute for the primary endpoint.

Secondary findings generally carry less weight when many outcomes are considered without a reported multiplicity plan. The registry lists 25 outcome measures, while the posted secondary results include 19 outcomes. The record does not explain whether these were all prespecified, how they were prioritized, or whether any multiplicity adjustment was planned. With multiple outcomes, an unadjusted result can appear notable even when it is not a robust signal across the outcome family.

The registry also does not report inferential analyses for the secondary outcomes. The recalculated comparisons are simple summaries based on the posted arm means and standard deviations. They can aid interpretation of direction and scale, but they do not establish a prespecified confirmatory analysis. In combination, these considerations mean the secondary outcomes are best treated as contextual or exploratory evidence, rather than as independent confirmation of the primary result.

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

• On-Treatment Sleep Duration
• Change in Fatigue Severity Scale (FSS) Score
• Change in Multidimensional Fatigue Inventory (MFI-20) Score
• Change in Sleep Inertia Questionnaire (SIQ) Score
• On-Treatment Sleep Inertia Likert Scale
• Change in Interleukin 1 Alpha (IL-1α)
• Change in Interleukin 1 Beta (IL-1β)
• Change in Interleukin 2 (IL-2)

9. Statistical Interpretation

10. Statistical Methods Explained

General statistical explanation: a randomized comparison estimates how the measured outcomes differed between assigned groups. Randomization is intended to make the groups comparable in expectation, but the registry summary alone does not establish that every observed difference is due to the assigned intervention. The analysis is based on group-level means and standard deviations for continuous outcomes.

What does a mean change represent?

The primary outcome is a continuous score change. For each participant with the relevant measurements, the change is defined as the baseline score minus the Day 14 score. A group mean is the average of those changes among the participants included in that arm's outcome summary. The clarithromycin mean is 1.7 and the placebo mean is 2.5. These numbers describe average changes; they do not say that every participant changed by the group average.

The standard deviation describes how dispersed the individual change scores are around the group mean. The posted standard deviations are 4.1 for clarithromycin and 4.0 for placebo. A standard deviation is not the uncertainty interval for the mean difference. It describes variation among participant values, whereas a confidence interval describes uncertainty around an estimated group comparison.

How is the between-arm estimate read?

The posted mean difference compares the clarithromycin mean change with the placebo mean change, using clarithromycin relative to placebo. The estimated difference is -0.8 points. Since positive change corresponds to a lower score at Day 14 than at baseline, a negative difference means that the average change was smaller in the clarithromycin arm than in the placebo arm. This sign interpretation depends on the registry's stated definition of change; it is not a separate clinical judgment.

The comparison is presented as a simple, unadjusted mean difference from the posted summary statistics. It is not described as an adjusted model estimate. The registry record does not report a model specification or covariate-adjustment plan. A simple contrast can be useful for expressing the observed scale difference, but it does not answer questions that would depend on an analysis model not reported in the record.

What does a confidence interval communicate?

General statistical explanation: a confidence interval expresses uncertainty in an estimate under the assumptions of the method used to construct it. A wider interval indicates less precision than a narrower interval on the same scale. For the primary result, the interval crosses zero. That means the posted interval includes no between-arm difference as well as differences in either direction. It should not be interpreted as proof that the groups are identical, and it does not state the probability that the true effect lies within the particular interval.

The unadjusted p-value for the primary comparison is 0.369. General statistical explanation: a p-value measures how unusual data at least as inconsistent with a specified null hypothesis would be under the assumptions of the test. It is not the probability that the null hypothesis is true, and it does not measure the size or importance of a difference. The registry does not report a multiplicity adjustment, so the p-value is not adjusted for the collection of outcomes.

Why can over-dispersion matter?

General statistical explanation: over-dispersion occurs when data vary more than a statistical model assumes. If an analysis treats observations as less variable or more independent than they actually are, its uncertainty estimates can be too small. It matters especially for count outcomes or clustered observations, where a simple model may fail to capture dependence or extra variation. The primary endpoint is summarized as a continuous mean and standard deviation, and the registry record does not report an over-dispersion assessment or a model in which such a feature is evaluated. It would therefore be inappropriate to claim that over-dispersion was present or addressed in this trial.

How should the secondary comparisons be understood?

The secondary summaries also use means and standard deviations for continuous measures, with comparisons stated as mean differences. Their analysis counts vary by outcome. For example, the posted sleep-duration summaries have 20 participants in the clarithromycin arm and 29 in the placebo arm, while the fatigue severity summaries have 34 and 42. The registry does not explain the differences in counts. It is not possible from the record alone to determine whether they reflect missing measurements, outcome-specific eligibility, or another reason.

General statistical explanation: comparing several outcomes creates multiple opportunities to observe apparently notable findings by chance. Adjustments for multiplicity can alter how evidence is interpreted across a family of tests. The record lists 25 outcome measures and does not report a multiplicity method. The displayed secondary p-values are unadjusted, so they should not be treated as if they account for all outcomes examined or planned.

The posted comparisons labeled as recalculated are simple unadjusted re-calculations from the posted summary statistics. They are not a substitute for analyses conducted under a prespecified statistical plan. The registry does not report inferential analyses for the secondary outcomes. The recalculated values are useful descriptive aids, but they do not establish how the trial's investigators planned to analyze those outcomes or whether other analyses were performed outside the registry record.

Finally, enrollment and outcome analysis counts are not interchangeable. The registry lists enrollment of 83, while the primary outcome summaries include the arm-specific counts shown for that endpoint. The population description says the analysis includes participants who completed the scale at at least one study timepoint. The record does not provide a full accounting of participant flow or the handling of incomplete paired measurements. Those omissions limit what can be concluded about the analysis population and missing data.

11. Confidence Intervals and Precision

The primary estimated mean difference is -0.8 points, with a confidence interval whose lower bound is -2.545 and whose upper bound is above zero. Because the interval crosses zero, the posted data are compatible with no difference as well as with differences in either direction under the interval's assumptions. Its span signals that the estimate is not precise enough to isolate a single direction of effect.

The confidence interval should be read on the Epworth Sleepiness Scale change-score scale. It is not a range of individual participants' outcomes, and it does not show where most individual scores fell. The standard deviations of 4.1 and 4.0 describe the spread of participant changes within the two arms, while the confidence interval describes uncertainty about their mean contrast. These answer different questions.

The unadjusted p-value of 0.369 is consistent with the interval's inclusion of zero, but it does not replace the interval's information about the range of estimates compatible with the data. A p-value alone would not show the range of plausible magnitudes or the direction that remains uncertain.

The registry record does not report a minimally important difference for this scale, so it is not possible to classify the interval's values as clinically important or unimportant based on the record. It also does not report the original analysis plan or the method used for any sponsor analysis. The confidence interval and p-value should therefore be understood as posted statistical summaries, not as a complete account of all inferential decisions.

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 80% power and participants per arm for 90% power. They use the primary outcome's observed effect as their starting point. For the full observed effect, the illustrations give 403 participants per arm for 80% power and 539 participants per arm for 90% power. For planning at 75% of the observed effect, the figures are 715 participants per arm for 80% power and 957 participants per arm for 90% power. For planning at 50% of the observed effect, they are 1,609 participants per arm for 80% power and 2,153 participants per arm for 90% power.

The stated assumptions are a two-sided significance level of 0.05, equal allocation between the two arms, and a normal approximation. The effect to detect is the stated fraction of the observed effect. These are planning illustrations computed from the observed effect, not the trial's original design assumptions; those original assumptions are not reported in the registry record. The figures are participants per arm, not total participants or total events. The time-to-event exception in the general planning description does not apply to these continuous outcomes.

In plain terms, the 80% power column gives a planning sample size intended to yield an 80% chance of detecting the specified effect under the stated assumptions if that effect is present. The 90% column uses a higher target chance and consequently requires more participants. Smaller target effects need more participants because they are harder to distinguish from sampling variation. A curve representing these planning scenarios should be read as a visualization of that relationship, not as another observed trial result.

This is not observed power. It is a prospective planning illustration based on the estimated effect, and it does not establish what the trial was designed or powered to detect.

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 = -0.800; pooled standard deviation σ = 4.048.
2. n = 2 × (1.96 + 0.842)² × 4.048² / -0.800² = 402.0, rounded up to 403 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 <- -0.8                      # observed difference in means
sigma <- 4.04845649599943                     # 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(4026958)
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 = 403 (80% power), 539 (90% power)
 75% of observed effect: n per arm = 715 (80% power), 957 (90% power)
 50% of observed effect: n per arm = 1,609 (80% power), 2,153 (90% power)
power.t.test: 403 
Simulated power at n = 403 per arm: 0.801 (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 25 outcome measures and 19 posted secondary outcomes. It does not report a multiplicity adjustment, a hierarchy for testing outcomes, or a family of outcomes designated for confirmatory inference. The displayed secondary p-values are unadjusted. When many outcomes are evaluated, the chance of seeing an apparently unusual result somewhere among them can increase. General statistical explanation: multiplicity procedures address that issue by controlling or otherwise accounting for repeated testing; the choice depends on the analysis objectives and prespecified plan.

The registry record does not report the trial's statistical analysis plan, interim analyses, or the original sample-size justification. It also does not report how the analyses were prespecified, whether outcome definitions changed, or how any deviations from a plan were handled. Those details should not be inferred from the fact that results are posted or from the planning calculations based on observed effects.

The primary analysis population is described as participants who completed the Epworth Sleepiness Scale during at least one study timepoint. That wording does not establish that every participant had paired baseline and Day 14 values, nor does it explain how incomplete measurements were handled. The record does not report a detailed missing-data strategy, reasons for missing observations, or sensitivity analyses. Counts vary across posted outcomes, but the record does not explain why.

The posted primary result has arm-specific outcome counts of 40 and 43, while other outcomes have different counts. Without participant-flow information, it is not possible to determine from the registry record whether the differences arise from missing data, outcome-specific collection, exclusions, or another cause. This limits assessment of how representative the analyzed participants are of all randomized participants.

The registry reports zero analyses in its analysis listing, while arm-level summaries and simple recalculated comparisons are available. This distinction matters: posted summary statistics do not provide the same detail as a full analysis report. A complete account of multiplicity, missingness, and analysis populations is not reported in the registry record.

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 0% reporting threshold.

Most frequent non-serious adverse event terms

The posted serious adverse event counts are zero in the clarithromycin arm and zero in the placebo arm. The corresponding at-risk counts are 40 and 43. No serious adverse event terms are listed. Deaths are reported as zero in both arms.

These counts describe what the registry record reports for the study's safety summaries. They should not be read as proof that no safety events of any kind occurred: the record separately lists other, non-serious adverse events, with 24 affected participants in the clarithromycin arm and 25 in the placebo arm. These are counts, not rates calculated for comparison, and they do not establish whether an event was caused by an assigned treatment.

The registry does not provide event descriptions for the non-serious counts in the posted summary, nor does it report additional detail about severity, timing, or attribution. Safety counts are also specific to the trial's recorded period and participants; they do not describe effects beyond the study. The figures should therefore be interpreted as the reported adverse-event accounting, not as a complete characterization of risk.

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

The primary result estimates a mean difference of -0.8 points in change in Epworth Sleepiness Scale score, comparing clarithromycin with placebo. The change definition means that a positive within-arm change corresponds to a lower Day 14 score than baseline. In the posted results, the average change was 1.7 points in the clarithromycin arm and 2.5 points in the placebo arm. The confidence interval crosses zero and the unadjusted p-value is 0.369, leaving substantial uncertainty about the direction and magnitude of the between-arm contrast.

This result does not establish that the two arms are equivalent. A confidence interval crossing zero is not proof of no difference, and the record does not define an equivalence margin. Conversely, the numerical point estimate does not establish a dependable treatment advantage or disadvantage. The evidence is a group-level estimate with uncertainty, based on the reported endpoint summaries.

The outcome also does not directly answer the proposed mechanisms question. The study description mentions brain activity, inflammation, gut bacteria, and cerebrospinal fluid as areas of investigation, but the primary result reported is a symptom-scale change. No mechanism can be inferred from the primary score comparison alone.

The record gives no minimally important difference for the Epworth Sleepiness Scale, so the clinical importance of the estimated scale contrast cannot be assessed from this information alone. It does not provide full participant-flow details, a missing-data strategy, a multiplicity plan, or the original statistical analysis plan. Those gaps constrain interpretation, especially for the numerous secondary outcomes.

The findings describe a completed Phase 2 trial over a 14-day assigned treatment period. They do not establish what would happen over a different duration, in populations beyond the listed hypersomnia conditions, or on outcomes not reported in the registry record. They should be understood as evidence about the posted measurements and their precision, not as medical advice or a broad claim about treatment.

17. Why This Trial Matters Statistically

This trial is statistically informative because it illustrates the difference between an observed point estimate and the uncertainty around that estimate. The primary mean difference is -0.8 points, but the confidence interval crosses zero. Looking at the interval alongside the estimate avoids treating a single number as a complete description of the evidence.

It also shows why outcome definition matters. The Epworth Sleepiness Scale change is baseline minus Day 14, so positive values represent a lower average score at Day 14. Reading the sign of the between-arm contrast requires keeping that orientation in mind. Without it, the numerical direction could be misinterpreted.

The record also gives a useful example of why planning values derived from an observed effect must be kept separate from original trial design assumptions. The planning illustrations use the observed effect and specified general assumptions; the trial's own original sample-size justification is not reported. Those values can show how sample size planning changes when the target effect becomes smaller, but they do not tell readers what the trial was intended to detect.

Finally, the registry presents many outcome measures but does not report a multiplicity strategy or detailed missing-data methods. These are central statistical considerations when interpreting secondary results and differing outcome counts. Distinguishing posted descriptive summaries from a full prespecified analysis helps keep conclusions aligned with the evidence actually documented in the record.

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 comparison is based on arm-level summary statistics, and the registry record does not report the full statistical analysis plan. It is therefore not possible to assess from the record whether the posted comparison matches a prespecified model or whether additional adjusted analyses were intended. The simple recalculated comparison should not be treated as a complete trial analysis.

The primary analysis population is defined as participants who completed the scale during at least one timepoint, but the record does not provide detailed participant flow, paired-measure availability, or reasons for missing outcome data. The outcome counts vary across measures, and the registry does not explain the differences. This prevents a full assessment of missingness or the comparability of the analyzed groups for each outcome.

The trial description states a planned recruitment of 92 participants, while registry enrollment is 83. The record does not explain this difference. It also does not report the original sample-size justification, so the observed enrollment cannot be assessed against a documented target or planned effect.

The treatment period is 14 days, and the primary outcome is measured at baseline and Day 14. The registry record does not describe longer-term outcome measurements in the primary endpoint, so the results do not characterize persistence beyond the reported timeframe. The record also does not give a clinically important threshold for the primary scale.

Finally, multiple outcomes are listed, but no multiplicity approach is reported. The secondary comparisons are unadjusted and their inferential status is not specified. The registry record also lacks detail about adverse-event types and attribution. These limitations call for restrained interpretation of both secondary and safety summaries.

19. Related Tutorials

20. Related Statistical Calculators

21. Sources

• ClinicalTrials.gov: Clarithromycin Mechanisms in Hypersomnia Syndromes — NCT04026958.
• Registry record last updated 2026-08-07; status last verified 2026-07.
• Results first posted 2026-08-07.
• 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

The registry record describes a completed Phase 2, randomized, double-masked, parallel trial sponsored by Emory University. It compares clarithromycin with matching placebo over 14 days in people with listed hypersomnia syndromes. Registry enrollment is 83, while the brief study description states planned recruitment of 92.

The primary outcome is change in Epworth Sleepiness Scale score from Day -1 to Day 14, defined as baseline minus Day 14. Mean changes were 1.7 for clarithromycin and 2.5 for placebo; the posted mean difference was -0.8. The confidence interval crosses zero, and the unadjusted p-value is 0.369.

Secondary outcomes show differing directions and counts. The record does not report a multiplicity method, detailed missing-data handling, the original sample-size justification, or a complete statistical analysis plan. Serious adverse events and deaths are reported as zero in both arms.