Efficacy of Atorvastatin as Adjunctive Treatment for Chronic Plaque Type Psoriasis: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Efficacy of Atorvastatin as Adjunctive Treatment for Chronic Plaque Type Psoriasis (NCT02432040), a randomized phase 2 study. The primary outcome is Mean Gross Change in Psoriasis Area and Severity Index (PASI) Scores From Baseline to the End of 6 Months.

2. Clinical Question

3. Trial Design

This was a randomized, triple-masked, parallel-group, placebo-controlled Phase 2 trial. It is listed as completed, with enrollment of 28. The registry lists a study start of 2013-02 and primary completion of 2013-10. The sponsor was the Philippine Dermatological Society. These design features describe the framework for comparing the study groups; they do not by themselves establish how precisely the primary comparison was estimated.

The active-treatment group received atorvastatin 40 mg once a day at night, alongside betamethasone valerate 0.1% ointment applied twice a day on a schedule of 3 weeks on and 1 week off, at the most. The control group received placebo tablets and the same topical-treatment instructions. Because both groups were asked to use the topical ointment, the contrast is the additional atorvastatin regimen against placebo tablets in the context of that topical care.

The primary outcome was the mean gross change in PASI score from baseline to the end of 6 months. The record describes the primary population as intention-to-treat, with inclusion requiring a baseline score and at least one post-baseline reading. It lists 11 participants in each group for the primary outcome, while overall enrollment was 28. The registry record does not explain the difference between enrollment and the outcome group counts, so no reason for it can be inferred.

The study also listed outcomes concerning monthly PASI changes, PASI-50 at the end of 3 months, quality of life, lipid levels, hsCRP, and adverse events. The registry record does not report the trial's original sample-size justification, detailed allocation procedure, or operational masking procedures. The trial's randomized and triple-masked labels are recorded, but further procedural detail is not reported in the registry record.

4. Participant Flow and Accounting

The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.

Before assignment: Patients who were not newly diagnosed with psoriasis and already on medications were allowed to be enrolled into the study as long as they have been free of any systemic anti-psoriatic therapy for at least 2 months or free from topical steroids for at least 2 weeks.

Overall Study

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: Intention-to-treat analysis was done. Patients with a baseline score and who had at least one reading after baseline were included.

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 Mean Gross Change in Psoriasis Area and Severity Index (PASI) Scores From Baseline to the End of 6 Months, measured over 6 months.

The primary endpoint is the mean change in Psoriasis Area and Severity Index (PASI) score from baseline to the end of 6 months. PASI combines assessments of plaque erythema, infiltration, and desquamation with estimates of affected body surface area across the head, upper extremities, trunk, and lower extremities. The registry describes severity ratings for the plaque features and a separate grading of affected area for each body region. The highest potential score is 72, and higher scores indicate worse psoriasis.

A change score expresses how the measured PASI score differs from baseline at the stated follow-up. The reported group means are negative, indicating that average scores fell from baseline in both groups. The primary comparison asks whether the average change differed between groups; it is not the same question as whether each group changed from its own baseline.

In general, a continuous endpoint such as PASI change preserves information about the amount of change across participants rather than reducing it to a yes-or-no threshold. A group mean gives a compact summary, while the standard deviation describes variation among participants. Neither alone shows every participant's course. PASI is used as the trial's clinical severity measure, and the registry lists mean change at 6 months as the primary outcome. The record does not report a threshold for interpreting an individual change as clinically important.

7. Results Posted in the Registry

• Atorvastatin: mean -2.15 versus -1.69 on control; difference -0.46 (95% CI -2.35 to 1.43), standardized effect d = -0.20; z-test p = 0.634.

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.

Percentage of Patients Achieving PASI-50 at the End of 3 Months

• Endpoint type: Binary: the percentage of participants with the event (counts rebuilt from the posted percentages and group sizes).
• Test: Unadjusted two-proportion z-test, with a Wald 95% confidence interval for the risk difference.
• Result:
  • Atorvastatin: 36.4% (4/11) versus 18.2% (2/11) on control; risk difference 18.2 percentage points (95% CI -18.3 to 54.6), risk ratio 2.00 (0.46–8.76); unadjusted two-proportion z-test p = 0.338.
• Interpretation:
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between Atorvastatin and the control. The interval gives the range of effects that remain compatible with the data.

The listed secondary outcomes span several kinds of information: PASI over monthly assessments, a threshold response at 3 months, quality of life at 6 months, lipid levels, hsCRP, and adverse events. This range can help describe whether changes in skin severity, patient-reported quality of life, laboratory measures, and safety outcomes move together. However, the registry record does not provide numerical results for most of these listed outcomes, so a complete pattern across domains cannot be assessed.

The posted PASI-50 comparison is a binary outcome, whereas the primary endpoint is a continuous mean change in PASI over 6 months. They answer different questions: one concerns meeting a response threshold at a specified time, and the other compares average score change at the primary time point. A categorical threshold can be useful for interpretation, but it discards information about the amount of change above or below that threshold. The secondary result therefore complements, rather than replaces, the primary comparison.

The secondary results do not resolve the uncertainty in the primary mean-change estimate. In general, different endpoints can yield different-looking estimates because they measure different constructs, use different time points, or summarize outcomes in different ways. The registry record does not report enough numerical detail across the secondary outcomes to assess consistency between them and the primary result. It also does not report whether the secondary analyses were prespecified in a hierarchy or adjusted for multiple comparisons.

Unadjusted secondary findings generally carry less confirmatory weight when many outcomes are examined, because chance differences become more likely across a collection of tests. This does not make secondary outcomes unimportant; it means that they are best interpreted as supporting or exploratory evidence unless the analysis strategy and control of multiplicity are clear. The registry lists six secondary outcomes, while detailed reported analyses are not available for the full set. Numerical findings for outcomes without posted results are not reported in the registry record.

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

• Monthly Mean Changes in PASI Scores
• Percentage of Patients Achieving PASI-50 at the End of 3 Months
• Mean Change in Dermatology Life Quality Index (DLQI) Scores After 6 Months
• Mean Change in Lipid Profile Levels
• Mean Change in hsCRP Levels
• Adverse Events

9. Statistical Interpretation

10. Statistical Methods Explained

For the primary outcome, the registry reports a mean and standard deviation for each group, then an estimated difference in means with a confidence interval and an unadjusted p-value. These summaries answer related but distinct questions. The mean describes the average change in a group. The standard deviation describes how dispersed the individual changes were around that group mean. The difference in means describes the estimated contrast between groups, rather than the change within either group by itself.

What does a change score represent?

Each participant's change is based on a PASI score at baseline and a later score. A negative group mean change indicates that the average follow-up score was lower than the average baseline score. The primary contrast compares the mean changes across the randomized groups. In general, comparing changes between groups is intended to distinguish the groups' average trajectories; a change within one group alone cannot establish that the intervention caused the change, because time, concurrent care, and other influences may also contribute.

The registry names the endpoint as mean gross change and gives its timeframe as 6 months. It does not report the statistical model or test used for this outcome, nor does it describe adjustment for baseline PASI or other covariates. Those details should not be inferred from the fact that group means and a confidence interval are posted. The posted p-value is described as unadjusted; the record does not specify a broader model or testing procedure behind it.

How should the standard deviations be read?

The primary outcome lists a standard deviation of 2.17 for atorvastatin and 2.36 for placebo. In general, a standard deviation describes participant-to-participant spread in the observed measure, not the precision of the group mean. A smaller standard deviation indicates observations closer to the group mean; a larger one indicates more spread. The standard deviations do not show the range of observations, whether the distribution is symmetric, or whether a few observations are influential.

In general, greater variation makes it harder to estimate a group mean difference precisely when the sample size is fixed. That is one reason to read the variability summaries together with the confidence interval. The registry does not provide individual participant values or a distributional plot in the registry record for this outcome, so the shape of the change-score distributions cannot be assessed from the group summaries alone.

What does the confidence interval add?

The estimated mean difference is -0.46, and its 95% confidence interval ranges from -2.355 to 1.435. In general, a confidence interval is a range of values generated by a statistical procedure that, under its assumptions and repeated use, would cover the underlying parameter at the stated rate. It communicates uncertainty around the point estimate in the units of the outcome. It is not a range containing a known percentage of individual participant outcomes, and it does not mean that the true value has a 95% probability of lying within this particular interval.

Here, the interval includes zero, the value corresponding to no difference in mean change. It also includes values in both directions. This makes the direction and magnitude of the group contrast imprecise. The confidence interval is not evidence that the groups are identical; a broad interval can remain compatible with meaningfully different values. The registry does not state a threshold for a clinically important between-group difference, so the interval cannot be classified against such a threshold from this record.

What does the p-value say?

The unadjusted p-value is 0.634. In general, a p-value describes how unusual data at least as incompatible with a specified null model would be if that model and the analysis assumptions were true. It is not a measure of the size or importance of a treatment difference, and it is not the probability that the null hypothesis is true. The registry does not report the precise test, its assumptions, or any multiplicity adjustment. The p-value therefore should be interpreted as the posted unadjusted result, rather than as a complete account of the statistical plan.

Because there are multiple outcomes listed, an unadjusted result does not account for the possibility of chance findings across a collection of tests. In general, testing more outcomes can make isolated small p-values less persuasive unless the testing strategy is planned and interpreted appropriately. The registry record does not report whether a hierarchy, family-wise error approach, or other multiplicity strategy was specified.

Why does over-dispersion matter in general?

For outcomes that count events or classify participants into categories, the variability may differ from what a simple model assumes. In general, over-dispersion means that the data vary more than the model's expected variability. If not handled appropriately, it can make standard errors and confidence intervals too optimistic. The primary endpoint is continuous, and the registry gives standard deviations; it does not report a model-based over-dispersion assessment. This concept is relevant as a general consideration, not as a finding about this trial.

The PASI-50 outcome is binary at the participant level: a participant either achieves the stated threshold or does not. In general, binary outcome comparisons depend on both the event counts and the denominators, and a small number of participants can make estimates unstable. The record posts an unadjusted risk difference and confidence interval for that secondary outcome, but it does not report the statistical test or a multiplicity procedure.

How should the analysis population be understood?

The primary population is called intention-to-treat in the registry, and the operational description includes patients with a baseline PASI score and at least one reading after baseline. In general, intention-to-treat analysis aims to preserve randomized group assignment in the comparison. The stated requirement for a post-baseline reading means the registry's operational definition matters when interpreting the label: it does not describe how people without such a reading were handled or whether imputation was used. No imputation method, sensitivity analysis, or detailed missing-data procedure is reported in the registry record.

The outcome counts are 11 per group, while the overall enrollment is 28. The record does not explain why the primary analysis counts differ from total enrollment. It is not possible to determine from these summaries whether the difference reflects missing outcomes, exclusions, or another reason. The sample-size illustrations are separate from the trial's original design rationale and should not be mistaken for evidence about the analysis population or actual power.

11. Confidence Intervals and Precision

The primary between-group estimate is -0.46 PASI units, and its 95% confidence interval extends from -2.355 to 1.435. The interval is wide enough to include a range of possible differences on either side of zero. Its lower end is compatible with a larger mean reduction for atorvastatin relative to placebo, while its upper end is compatible with a larger mean reduction for placebo. The estimate therefore gives a direction at its center, but the interval shows that the direction is not established precisely.

In general, a confidence interval conveys precision in the scale of the outcome: narrower intervals represent more precise estimates, while wider intervals leave more uncertainty about the underlying contrast. The interval's inclusion of zero does not prove that the treatments have equal effects. It means that the posted data and analysis do not distinguish the estimated difference from zero at the confidence level used, under the analysis assumptions. The interval also does not tell whether any value within it would be clinically important.

The 11 participants listed per group for the primary outcome, together with the standard deviations of 2.17 and 2.36, provide context for the uncertainty. A limited number of observations can produce an imprecise estimate, particularly when individual change scores vary. The registry does not report participant-level values, subgroup precision, or a prespecified clinically important difference. Those omissions limit further interpretation of the interval's practical implications.

The confidence interval and p-value are related summaries of the same comparison, but they serve different communication purposes. The interval gives a range in outcome units; the unadjusted p-value, 0.634, summarizes compatibility with a specified null model under the test's assumptions. Neither resolves the uncertainty or establishes equivalence. The statistical test details and any adjustment are not reported in the registry record.

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 sample-size figures are planning illustrations based on the observed effect, not the trial's original design calculation. For these non-time-to-event outcomes, the figures are participants per arm, not total participants across both groups. The planning assumptions listed in the registry are a two-sided significance level of 0.05, equal allocation between the two arms, and a normal approximation. Each row uses the stated fraction of the observed effect: 100%, 75%, or 50%.

The 80% power column describes the number of participants per arm that the planning calculation associates with an 80% chance of detecting the chosen effect under those assumptions, if that effect and the planning model were correct. The 90% power column uses a higher target chance of detection, so it requires more participants per arm for the same assumed effect. These are conventional planning quantities, not guarantees that a future study will detect an effect.

For the primary mean-change comparison, the planning figures are 382 participants per arm for 80% power and 511 for 90% power when using 100% of the observed effect. For planning at 75% of the observed effect, the figures are 678 and 908 participants per arm. For 50% of the observed effect, they are 1,526 and 2,042 participants per arm. The corresponding figures for the secondary PASI-50 comparison are 93 and 124 participants per arm at 100% of the observed effect, 158 and 210 at 75%, and 333 and 445 at 50%.

Smaller effects are harder to distinguish from random variation, so planning for a smaller effect requires more participants. These calculations use the observed effect as their starting point, which is uncertain in a small trial; they should not be treated as a validated estimate of the effect expected in a future study. This is not observed power. The trial's own original sample-size assumptions and justification are 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 = -0.460; pooled standard deviation σ = 2.267.
2. n = 2 × (1.96 + 0.842)² × 2.267² / -0.460² = 381.3, rounded up to 382 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 <- -0.46                      # observed difference in means
sigma <- 2.26699139830746                     # 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(2432040)
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 = 382 (80% power), 511 (90% power)
 75% of observed effect: n per arm = 678 (80% power), 908 (90% power)
 50% of observed effect: n per arm = 1,526 (80% power), 2,042 (90% power)
power.t.test: 382.2 
Simulated power at n = 382 per arm: 0.795 (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 endpoint and multiple secondary outcomes, covering PASI, quality of life, laboratory measures, and adverse events. Each additional outcome can address a distinct question, but examining several outcomes also raises the issue of multiplicity. In general, if many hypotheses are tested, the chance of finding at least one apparently notable result by chance can increase. Prespecified outcome priorities and a defined multiplicity strategy help readers distinguish confirmatory tests from exploratory analyses.

The registry record does not report a multiplicity adjustment, a testing hierarchy, or a statistical analysis plan that explains how primary and secondary hypotheses were prioritized. The posted p-value for the primary comparison is unadjusted. The secondary PASI-50 comparison also has an unadjusted p-value, and analyses for the full set of listed secondary outcomes are not reported. Accordingly, the findings should not be read as though a family of tests was necessarily controlled at a prespecified overall error rate.

The primary population is described as intention-to-treat, with inclusion requiring a baseline PASI score and at least one reading after baseline. This definition gives some information about who contributed to the primary outcome, but the registry does not describe how missing follow-up measurements were handled. No imputation method, missing-data sensitivity analysis, or explanation for the difference between enrollment and the primary outcome group counts is reported in the registry record.

In general, missing outcome data can affect both precision and the validity of a comparison, particularly if the likelihood of missingness is related to participant characteristics or outcomes. The posted summaries cannot establish whether missingness was balanced or whether the observed cases represent all randomized participants. The registry record also does not report interim analyses, stopping rules, or the original sample-size justification. These design and analysis details are relevant to interpreting a trial, but their absence from the record is not evidence that a particular procedure was or was not used.

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 non-serious adverse event terms

The registry reports serious adverse events for 14 participants at risk in each group, with 0 participants affected in the atorvastatin group and 0 in the placebo group. This means no serious adverse events are recorded as affecting participants in either group in the posted safety summary. The record does not list serious adverse event terms.

For other, non-serious adverse events, 2 of 14 participants at risk were affected in the atorvastatin group and 0 of 14 in the placebo group. These counts are descriptive and should be read with the group sizes in mind. A small study may provide limited information about uncommon events, and a count of zero does not establish that an event cannot occur.

Deaths are not reported in the registry safety record. The listed safety population differs from the primary-outcome group counts, and the registry does not explain the difference. These results describe the posted adverse-event counts; they do not by themselves establish comparative safety, identify causality, or provide a complete account of adverse-event severity and timing.

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

The primary result is an estimate of the difference in average PASI change between the atorvastatin-plus-topical-treatment group and the placebo-plus-topical-treatment group at 6 months. The estimate was -0.46 units, with a 95% confidence interval from -2.355 to 1.435. Both groups had negative mean changes from baseline, and the interval around the between-group estimate includes zero. The results therefore leave substantial uncertainty about the size and direction of the average difference.

This comparison does not answer whether participants in either group improved because of their assigned tablets alone. Both groups were asked to use betamethasone valerate ointment, and the contrast is the addition of atorvastatin versus placebo in that context. Nor does the primary comparison establish that the groups are equivalent: no equivalence margin is reported, and a non-significant result is not an equivalence test.

The registry describes a randomized, triple-masked, placebo-controlled Phase 2 trial, but the primary outcome analysis includes 11 participants per group and the record does not explain the relationship between those counts and enrollment of 28. It also does not report the original sample-size justification, missing-data methods, or multiplicity strategy. Those limits constrain how broadly or confidently the findings can be generalized beyond the analyzed participants and reported endpoint.

The endpoint is a measure of psoriasis area and severity, not a direct measure of every aspect of a participant's health or experience. Other listed outcomes address quality of life, lipids, hsCRP, and adverse events, but numerical results are not reported for most secondary measures. The posted results cannot establish a complete benefit-risk profile or explain mechanisms linking changes in clinical scores and laboratory markers.

In general, an estimate with a broad confidence interval is best treated as uncertain rather than as proof of either benefit or no effect. The trial offers a small randomized comparison and a point estimate for the primary outcome; it does not settle the magnitude of the difference. No medical recommendation follows from these registry results alone.

17. Why This Trial Matters Statistically

This trial illustrates why a point estimate, its uncertainty, and the analysis population all matter when reading a small randomized study. The primary comparison is not captured by the direction of the group means alone. The estimated difference of -0.46 is accompanied by an interval from -2.355 to 1.435, which spans both directions and includes zero. The interval is central to understanding how much the data narrow the range of plausible group differences.

The registry also makes clear that enrollment and endpoint analysis counts are not always the same quantity. Enrollment is 28, while 11 participants per group are listed for the primary analysis and 14 per group for the safety summary. These are distinct analysis counts, and the record does not explain the differences. Noticing that distinction helps prevent readers from treating every posted result as if it used the same population.

The study also has several outcome domains, including clinical severity, a threshold response, quality of life, laboratory measures, and adverse events. Such breadth can be useful, but it increases the importance of knowing which analyses were planned and how multiple comparisons were handled. Those methods are not reported in the registry record, limiting the strength of conclusions that can be drawn from secondary findings.

Finally, the planning illustrations demonstrate how sample-size requirements depend on the assumed effect and desired power. They are not the trial's original design justification, and they do not establish the probability that this completed trial detected an effect. Separating prospective planning quantities from observed results is essential to avoid confusing a small study's uncertainty with evidence of no difference.

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 outcome analysis lists 11 participants per group, while enrollment was 28. The registry record does not explain the difference, and therefore does not allow the reasons for the analysis counts to be identified. Safety summaries use a separate at-risk count of 14 per group. Because the analysis populations are not fully reconciled, readers cannot determine from the record alone how outcome availability related to enrollment or safety follow-up.

The primary population is labeled intention-to-treat, but the stated inclusion rule requires both a baseline PASI score and at least one post-baseline reading. The registry does not report how participants without post-baseline readings were handled, whether data were imputed, or whether sensitivity analyses examined the consequences of missing data. The label and operational description should both be considered when evaluating the scope of the primary result.

The estimated primary difference is imprecise, with a confidence interval that includes zero and values in either direction. The registry does not state a clinically important between-group difference, so the interval cannot be used to judge whether its possible values are clinically meaningful. The original sample-size calculation and its assumptions are also not reported; the planning illustrations based on the observed effect are not a substitute for that information.

Further limits include the absence of detailed statistical methods, multiplicity procedures, and numerical results for most secondary outcomes. The registry record does not report the exact test used for the primary comparison, a detailed missing-data plan, interim-analysis methods, or outcome-level analyses across the full secondary set. The available summary also does not include participant-level data, which would be needed to inspect distributions or influential observations.

19. Related Tutorials

20. Related Statistical Calculators

21. Sources

• ClinicalTrials.gov: Efficacy of Atorvastatin as Adjunctive Treatment for Chronic Plaque Type Psoriasis — NCT02432040.
• Registry record last updated 2015-11-23; status last verified 2015-10.
• Results first posted 2015-11-23.
• 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

NCT02432040 is a completed randomized, triple-masked, parallel-group, placebo-controlled Phase 2 trial sponsored by the Philippine Dermatological Society. It enrolled 28 participants and compared atorvastatin 40 mg at night plus betamethasone valerate ointment with placebo tablets plus the same topical-treatment instructions.

The primary outcome was mean PASI change from baseline to 6 months. The registry lists 11 participants per group; mean changes were -2.15 for atorvastatin and -1.69 for placebo. The estimated between-group difference was -0.46, with a 95% confidence interval from -2.355 to 1.435 and an unadjusted p-value of 0.634. The interval indicates substantial uncertainty about the size and direction of the average difference.

The record lists secondary outcomes and adverse-event summaries, but numerical results are not reported for most secondary measures. The registry does not report the trial's original sample-size justification, multiplicity strategy, or detailed missing-data methods.