Safety and Efficacy Study of Armodafinil (CEP-10953) in the Treatment of Excessive Sleepiness Associated With Narcolepsy: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Safety and Efficacy Study of Armodafinil (CEP-10953) in the Treatment of Excessive Sleepiness Associated With Narcolepsy (NCT00078377), a randomized phase 3 study. The primary outcome is Change From Baseline in Maintenance of Wakefullness Test (MWT) Score at 12 Weeks.

2. Clinical Question

The trial addressed an objective measure of wakefulness in adults experiencing excessive sleepiness associated with narcolepsy. The MWT assesses the ability to stay awake during a series of tests, and the primary outcome uses the average of four tests at scheduled times during the day. The comparison is based on change from baseline, so the reported group means describe the average change over the study period rather than the groups’ endpoint values alone.

The registry describes a 12-week randomized, double-blind, placebo-controlled parallel-group study. It lists two armodafinil doses and placebo, and an enrollment of 196. The posted primary outcome analysis has fewer participants than that enrollment figure, reflecting the analysis populations described in the outcome record. The results therefore speak to the MWT change observed among participants included in the efficacy analysis, with the interpretation also depending on how missing efficacy observations were handled. That handling is not reported in the registry record.

3. Trial Design

The registry describes a Phase 3 randomized, double-blind, placebo-controlled, parallel-group study of armodafinil in adults with excessive sleepiness associated with narcolepsy. The study compared armodafinil at 250 mg per day and 150 mg per day with placebo. The official title specifies a 12-week study. The registry lists enrollment of 196 and marks the trial as completed. The study start is listed as 2004-03, with primary completion at 2005-01.

Randomization and double masking are reported, but the method used to generate the allocation sequence, how allocation was concealed, and who was masked are not reported in the registry record. Details about whether the placebo matched the study drug are also not reported. A parallel-group design assigns participants to a group for comparison over the study period; the registry does not report further operational details about treatment assignment or adherence.

The primary outcome is change from baseline in MWT score at 12 weeks, measured in minutes. The endpoint description says that mean sleep latency was averaged across four MWT tests and assessed at weeks 4, 8, and 12, with week 12 or the last post-baseline visit designated as the primary efficacy assessment. The registry’s brief summary also refers to Clinical Global Impressions of Change ratings, but no secondary outcome results are posted.

The outcome record describes a safety analysis set of 194 patients, including two who withdrew after randomization but before receiving study drug. It describes a full analysis set of 176 patients, with 18 participants who withdrew from the study considered non-evaluable for efficacy. The posted efficacy group sizes are 60 for armodafinil 250 mg per day, 58 for armodafinil 150 mg per day, and 58 for placebo. The registry does not report a detailed protocol, sample-size justification, analysis schedule, or the original statistical analysis plan.

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.

Before assignment: 2 female patients withdrew after randomization but prior to receiving study drug (1 withdrew consent and 1 was lost to follow-up)

Overall Study

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: Safety Analysis set of 194 total patients: 2 patients withdrew after randomization but prior to receiving study drug (1 withdrew consent and 1 was lost to follow-up). Full Analysis set of 176 total patients: 18 patients that had withdrawn from the study were non-evaluable for efficacy.

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 Maintenance of Wakefullness Test (MWT) Score at 12 Weeks, measured over change from baseline at 12 weeks.

The primary endpoint is change from baseline in the Maintenance of Wakefulness Test score at 12 weeks, expressed in minutes. The MWT is an objective assessment of sleepiness: it measures how long a participant can remain awake during testing. Longer sleep latency indicates a greater ability to remain awake. The registry describes the endpoint as the average sleep latency across four tests scheduled at 0900, 1100, 1300, and 1500.

Using change from baseline focuses the comparison on how the measured latency shifted during the study, rather than only on the final measurement. The endpoint description says assessments were made at weeks 4, 8, and 12, while the primary efficacy variable was the mean change at week 12 or the last post-baseline visit. The group means are therefore average changes in MWT latency for participants in each analysis group. A positive change indicates an increase in latency relative to baseline; a negative change indicates a decrease.

This endpoint is used because the ability to remain awake is directly captured by the MWT, and the test provides a measured outcome rather than relying solely on a participant’s report. That general rationale does not establish that the test captures every aspect of sleepiness or daily functioning. The registry does not report details about the MWT’s conduct beyond the test duration version, the four scheduled test times, and the averaging approach. It also does not report the rules for choosing a last post-baseline observation when a week 12 result was unavailable.

The registry’s brief summary mentions Clinical Global Impressions of Change ratings as another measure of general condition. However, the posted primary outcome results concern MWT change, and no secondary outcome results are posted.

7. Results Posted in the Registry

• Armodafinil 250 mg/Day: mean 2.60 versus -1.90 on control; difference 4.50 (95% CI 2.13 to 6.87), standardized effect d = 0.69; z-test p = <0.001.
• Armodafinil 150 mg/Day: mean 1.30 versus -1.90 on control; difference 3.20 (95% CI 0.80 to 5.60), standardized effect d = 0.49; z-test p = 0.009.
• Armodafinil Combined Group (250 mg/Day and 150 mg/Day): mean 1.90 versus -1.90 on control; difference 3.80 (95% CI 1.70 to 5.90), standardized effect d = 0.59; z-test p = <0.001.

8. Statistical Interpretation

9. Statistical Methods Explained

The endpoint is continuous: it is a change in MWT latency measured in minutes, summarized as a mean and standard deviation in each group. A mean difference compares the average changes between two groups. For the unadjusted comparisons, the placebo mean change is the reference and each armodafinil group is compared with it. A positive contrast in these results corresponds to a higher mean change in the armodafinil group than in the placebo group.

What does a mean difference express?

A mean difference retains the endpoint’s original unit, so its value is interpreted in minutes of MWT change. It describes a difference between group averages, not a difference that every participant experienced. The posted means are 2.6 minutes for armodafinil 250 mg/day, 1.3 minutes for armodafinil 150 mg/day, -1.9 minutes for placebo, and 1.9 minutes for the combined armodafinil group. The recalculated pairwise estimates compare those reported averages using the posted group sizes and standard deviations.

The standard deviation describes variation among participant measurements within a group. It is not the same as the standard error, which describes the uncertainty of an estimated mean. The outcome record reports standard deviations of 6.24, 6.31, and 6.87 for the 250 mg/day, 150 mg/day, and placebo groups, respectively. The combined group standard deviation is 6.28. The recalculated comparisons use pooled standard deviations, which summarize the within-group variation for a two-group contrast under the calculation’s assumptions.

What does the recalculation assume?

The recalculated estimates are simple, unadjusted comparisons derived from the posted summary statistics. They do not reproduce an adjusted model or account for details that are not in the registry record. A recalculation can help check how group means relate to one another, but it is not equivalent to the sponsor’s analysis when that analysis uses a different method or information not represented in the summaries. The sponsor reports an ANCOVA analysis, and the registry data flag a discrepancy between that result and the recalculated combined comparison. The sponsor’s analysis takes precedence in that circumstance.

ANCOVA, in general, compares outcome means while accounting for one or more covariates. If baseline outcome is included, for example, an ANCOVA can estimate a treatment contrast conditional on baseline values. This is a general description of the method, not a statement that baseline MWT was included in this trial’s model. Which covariates, coding choices, missing-data assumptions, and contrast definitions were used in the sponsor’s ANCOVA are not reported in the registry record. The reported analysis is therefore identified as ANCOVA, but its full specification cannot be assessed from the registry entry.

How should the p-values be read?

A p-value is a measure of how unusual data at least as inconsistent with a null model would be if that model and the analysis assumptions were correct. It does not give the probability that the null model is true, and it does not describe the magnitude of a difference. The recalculated p-values are unadjusted: they accompany separate comparisons of each dose group and the combined group with placebo, without a reported multiplicity adjustment. The registry’s reported ANCOVA p-value is 0.002. These p-values should not be treated as interchangeable because the underlying analyses differ.

In general, multiple comparisons can increase the chance of at least one apparently notable result when each comparison is assessed separately. A prespecified strategy can address this issue, but the trial’s approach to multiplicity is not reported in the registry record. The planning illustration’s two-sided significance level of 0.05 is an assumption used for those planning calculations; it is not evidence of the original trial’s analysis threshold.

What do the confidence intervals add?

A confidence interval gives a range of values compatible with the data and the analysis method at the stated confidence level. It conveys both the estimated contrast and its statistical precision. A wider interval indicates less precision than a narrower interval, all else equal. The recalculated intervals are based on the unadjusted comparisons; the sponsor’s interval comes from its reported ANCOVA. The intervals should be interpreted with their analysis method in mind rather than treated as a single common estimate.

General statistical interpretation also depends on design and data quality. Randomization can support fair group comparisons when implemented appropriately, while masking can reduce some forms of bias. The registry reports randomized and double-blind design, but it does not report the randomization procedure, masking details, adherence, or protocol deviations. It also does not give a full account of missing outcome data or the handling of withdrawals beyond the analysis-population description. Those omissions limit assessment of how well the reported analyses address potential bias.

What is not established by these methods?

The endpoint summaries and contrasts do not establish that all participants had similar responses, since group means conceal individual variation. They do not resolve the sponsor-versus-recalculation discrepancy, and they do not provide results for the Clinical Global Impressions of Change measure mentioned in the brief summary. Details of the original statistical plan, sample-size justification, interim analyses, and missing-data methods are not reported in the registry record. General statistical concepts can clarify what the estimates represent, but they cannot fill in those trial-specific details.

10. Confidence Intervals and Precision

The recalculated mean difference for armodafinil 250 mg/day versus placebo is 4.5 minutes, with a 95% confidence interval from 2.13 to 6.87. For armodafinil 150 mg/day versus placebo, the recalculated difference is 3.2 minutes, with a 95% confidence interval from 0.799 to 5.601. The combined armodafinil comparison has a recalculated difference of 3.8 minutes, with a 95% confidence interval from 1.7 to 5.9. These intervals quantify uncertainty around unadjusted estimates based on posted group summaries.

A confidence interval is not a range containing most individual participant outcomes. It is an interval estimate for the group contrast under a specified method and its assumptions. Its width reflects statistical precision: narrower intervals generally indicate a more precise estimate, while wider intervals leave greater uncertainty about the contrast. Precision does not by itself establish clinical importance, and an interval cannot address biases arising from design or missing data that the calculation does not account for.

The sponsor’s reported ANCOVA result is 3.8, with a 95% confidence interval from 1.02 to 4.61 and p = 0.002. Its interval differs from the recalculated interval for the combined armodafinil comparison. The registry record flags a discrepancy, so the sponsor’s own analysis takes precedence. Since the ANCOVA specification is not reported in detail, the available record does not permit a full explanation of the difference.

The group standard deviations are 6.24 for armodafinil 250 mg/day, 6.31 for armodafinil 150 mg/day, 6.87 for placebo, and 6.28 for the combined group. These describe observed spread, not precision of the treatment contrast. The recalculated intervals also depend on the group sizes and the unadjusted method. They should not be interpreted as accounting for multiplicity, missing outcomes, or covariate adjustment unless those features are explicitly part of the analysis.

11. 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 the pairwise comparisons; they are not total event counts. The planning assumptions are a two-sided significance level of 0.05, equal allocation between the two arms, a normal approximation, and an effect to detect set to a stated fraction of the observed effect. These are planning illustrations based on the observed estimates, not the trial’s original design assumptions. The original sample-size justification and design assumptions are not reported in the registry record.

For the 250 mg/day comparison, planning for 100% of the observed effect gives 34 participants per arm for 80% power and 45 participants per arm for 90% power. Planning for 75% gives 60 and 80 participants per arm, respectively; planning for 50% gives 134 and 179. For the 150 mg/day comparison, the corresponding pairs are 67 and 90 for 100%, 119 and 159 for 75%, and 267 and 358 for 50%. For the combined-group comparison, they are 46 and 62 for 100%, 82 and 109 for 75%, and 183 and 245 for 50%.

In plain terms, power is the probability that a planned analysis will detect an effect of the chosen size under the planning assumptions. The 80% column gives the number per arm associated with an 80% chance under those assumptions; the 90% column gives the number per arm associated with a 90% chance. A smaller target effect requires more participants because it is harder to distinguish from sampling variation. The figures depend on the observed effect used as their starting point and should not be read as definitive design recommendations.

These calculations are not observed power. They are prospective planning illustrations, not a description of the trial’s actual power or proof that the trial was adequately sized.

12. 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 = 4.500; pooled standard deviation σ = 6.557.
2. n = 2 × (1.96 + 0.842)² × 6.557² / 4.500² = 33.3, rounded up to 34 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 <- 4.5                      # observed difference in means
sigma <- 6.55713726697337                     # 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(78377)
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 = 34 (80% power), 45 (90% power)
 75% of observed effect: n per arm = 60 (80% power), 80 (90% power)
 50% of observed effect: n per arm = 134 (80% power), 179 (90% power)
power.t.test: 34.3 
Simulated power at n = 34 per arm: 0.798 (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.

13. Analyses Reported by the Sponsor

The registry reports a sponsor analysis using ANCOVA across the three listed groups. It gives a mean difference of 3.8, a 95% confidence interval from 1.02 to 4.61, and p = 0.002. The registry does not provide enough detail to identify the exact model specification or the precise contrast represented by this result.

The recalculation uses posted group means, standard deviations, and group sizes to form unadjusted comparisons. In particular, the recalculated combined armodafinil comparison versus placebo is a mean difference of 3.8, with a 95% confidence interval from 1.7 to 5.9 and p < 0.001. Although the point estimate matches the sponsor’s reported value, the interval and p-value differ. The dose-specific recalculations also report separate unadjusted comparisons with placebo.

The registry data flag this as a discrepancy. Accordingly, the sponsor’s own ANCOVA analysis takes precedence over the simple recalculation. The recalculation is useful for understanding the relation between the posted group summaries, but it does not reproduce an adjusted analysis and should not be substituted for the sponsor’s result. Because details of the ANCOVA and its contrasts are not reported in the registry record, the reason for the difference cannot be determined from the available entry.

14. Multiplicity, Missing Data and Analysis Populations

The registry’s brief summary refers to both MWT sleep latency and Clinical Global Impressions of Change ratings in describing the primary objective. The posted primary outcome is change from baseline in MWT score at 12 weeks, and the record lists two outcome measures and two analyses. However, no secondary outcome results are posted. The registry record does not clarify whether the two measures were treated as co-primary, how they were prioritized, or how their results were intended to be combined or interpreted.

Several recalculated contrasts are reported: each armodafinil dose versus placebo and the combined armodafinil group versus placebo. These are unadjusted comparisons. No multiplicity adjustment or prespecified strategy for controlling error across outcomes or comparisons is reported in the registry record. In general, evaluating multiple contrasts separately can increase the chance of at least one statistically notable result, so the analysis plan matters when interpreting a collection of p-values. The planning illustration’s 0.05 significance level does not establish the threshold or multiplicity strategy used in the trial’s own analysis.

The outcome description identifies a safety analysis set of 194, including two participants who withdrew after randomization but before receiving study drug. It identifies a full analysis set of 176, with 18 participants who withdrew from the study considered non-evaluable for efficacy. The registry does not report the detailed rules for inclusion in the full analysis set, the reasons for all withdrawals, or the handling of missing week 12 measurements. It also does not report whether the last post-baseline observation was used for every participant with a missing week 12 result or how that procedure was implemented.

Details about imputation, sensitivity analyses for missing data, protocol deviations, interim analyses, and the original statistical analysis plan are not reported in the registry record. These omissions limit assessment of whether the analysis populations and missing-outcome handling could affect the estimated contrasts. The posted group sizes and analysis-set descriptions are informative, but they do not replace a full account of the prespecified analysis methods.

15. 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: angioneurotic oedema (1.6%).

The serious adverse event counts are reported against the safety groups: 0 among 67 participants at risk in the armodafinil 250 mg/day group, 1 among 64 at risk in the armodafinil 150 mg/day group, and 0 among 63 at risk in the placebo group. These are counts, not comparative risk estimates, and they should be read in the context of the number of participants at risk in each group. The registry lists angioneurotic oedema at 1.6% among the top serious adverse event terms.

The posted serious-event figures do not establish whether an event was caused by treatment. The registry entry does not provide enough detail to assess event severity beyond its serious-event classification, timing, duration, or relationship to study drug. Deaths are not reported in the registry record. The absence of a reported death count should not be interpreted as a confirmed count of zero.

The registry also reports other adverse events affecting 29 of 67 participants at risk in the 250 mg/day group, 21 of 64 in the 150 mg/day group, and 11 of 63 in the placebo group. These counts are distinct from the serious-event counts and do not by themselves provide a complete safety comparison. Differences between counts cannot establish causation, particularly without event definitions, exposure information, details of ascertainment, and a fuller account of the safety analysis.

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

The posted results show positive mean change in MWT latency in each armodafinil group and negative mean change in the placebo group. The unadjusted recalculations estimate higher mean change relative to placebo for the 250 mg/day group, the 150 mg/day group, and the combined armodafinil group. Their confidence intervals describe uncertainty around those unadjusted contrasts. The registry also reports a sponsor ANCOVA result, and that analysis takes precedence because the registry data flag a discrepancy with the recalculation.

The outcome is a measure of the ability to remain awake during the MWT, not a comprehensive measure of every aspect of sleepiness, daily functioning, or health. The brief summary mentions Clinical Global Impressions of Change, but no secondary results for that measure are posted. The findings therefore do not establish what happened on that measure or on other outcomes not reported in the registry entry.

Group averages do not show how individual participants responded. The posted standard deviations indicate variability in the outcome, but the registry does not provide participant-level results or response distributions. A mean contrast should not be taken to mean that every participant experienced a change of that size or in the same direction.

The registry describes a randomized, double-blind design, but it does not report the detailed randomization and masking procedures, adherence, or protocol deviations. The efficacy analysis set excludes participants described as non-evaluable after withdrawal, and the missing-data methods are not reported in detail. Those factors affect how confidently the observed estimates can be interpreted as an unbiased comparison.

The results relate to the study population, treatment groups, outcome definition, and follow-up described in the registry. The entry does not establish longer-term outcomes, results in populations outside the described adult narcolepsy population, or effects on measures that were not posted. Statistical estimates describe the observed data under an analysis method; they are not, on their own, medical advice or a complete account of treatment effects and harms.

17. Why This Trial Matters Statistically

This trial offers a useful example of how the same continuous endpoint can be described at several levels: group mean change, an unadjusted mean difference, a confidence interval, and a model-based analysis reported by the sponsor. Each addresses a different question. Group means describe observed change within groups; contrasts compare groups; intervals communicate precision; and the sponsor’s ANCOVA represents a reported adjusted analysis whose details are not fully available in the registry.

The discrepancy between the sponsor result and the simple recalculation is statistically important because an unadjusted calculation from summary statistics is not necessarily equivalent to a model-based analysis. The matching point estimate for the combined-group comparison does not make the analyses identical: their confidence intervals and p-values differ. Giving precedence to the sponsor analysis while clearly identifying the recalculation as unadjusted avoids treating unlike methods as interchangeable.

The analysis populations also matter. The enrollment figure is 196, whereas the outcome description identifies 194 in the safety analysis set and 176 in the full analysis set. The efficacy group sizes are 60, 58, and 58. Understanding these distinctions helps readers avoid treating the enrollment count as the denominator for every reported outcome. The registry provides some explanation for exclusions and withdrawals but not the complete missing-data procedures.

Finally, planning illustrations based on observed effects can help show how sample size changes with the effect chosen for planning. They do not recover the trial’s original design rationale, which is not reported, and they are not observed power. Together, these features make the record a practical case for separating descriptive summaries, sponsor analyses, and planning calculations, while keeping uncertainty and reporting gaps visible.

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 registry entry does not report the detailed protocol or the original statistical analysis plan. The sample-size justification, randomization procedure, allocation concealment, and masking details are not reported in the registry record. Although the study is described as randomized and double-blind, the available entry does not allow assessment of how those procedures were implemented.

The sponsor’s analysis is identified as ANCOVA, but its model specification, covariates, contrast definitions, and missing-data assumptions are not reported. The recalculated estimates are unadjusted summaries and differ from the sponsor analysis, so they cannot resolve what the adjusted result would be under a fully described model. The registry flags this discrepancy, and the sponsor’s own analysis takes precedence.

The analysis populations are described, including the safety analysis set of 194 and full analysis set of 176, but detailed inclusion rules and reasons for withdrawals are incomplete. Missing-outcome handling, sensitivity analyses, and the implementation of the last post-baseline observation approach are not reported in the registry record. These omissions limit evaluation of how missing data may influence the endpoint estimates.

The brief summary mentions Clinical Global Impressions of Change ratings, but no secondary outcome results are posted. The record does not report the trial’s multiplicity strategy, interim analyses, adherence, or protocol deviations. The posted serious adverse event information is limited to group counts, numbers at risk, and a listed serious-event term; deaths are not reported in the registry record. These reporting limits mean the posted data do not provide a complete account of efficacy outcomes, safety, or the analyses used.

19. Related Tutorials

20. Related Statistical Calculators

21. Sources

• ClinicalTrials.gov: Safety and Efficacy Study of Armodafinil (CEP-10953) in the Treatment of Excessive Sleepiness Associated With Narcolepsy — NCT00078377.
• Registry record last updated 2013-07-19; status last verified 2013-07.
• Results first posted 2010-01-21.
• 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

NCT00078377 is a completed Phase 3 randomized, double-blind, placebo-controlled, parallel-group study of armodafinil for adults with excessive sleepiness associated with narcolepsy. The registry lists enrollment of 196 and a 12-week study. Participants were assigned to armodafinil 250 mg/day, armodafinil 150 mg/day, or placebo.

The posted primary endpoint is change from baseline in MWT score at 12 weeks. The mean changes were 2.6 minutes, 1.3 minutes, and -1.9 minutes for the 250 mg/day, 150 mg/day, and placebo groups, respectively. The sponsor reports an ANCOVA result of 3.8, with a 95% confidence interval from 1.02 to 4.61 and p = 0.002. The registry flags a discrepancy with unadjusted recalculations, so the sponsor analysis takes precedence.

The entry describes safety and efficacy analysis populations but does not report the full statistical plan, original sample-size justification, detailed missing-data methods, or secondary outcome results.