Open-label Study of Subcutaneous Secukinumab to Evaluate Efficacy and Safety in Patients With Plaque Psoriasis Who Had Inadequate Response to Cyclosporine A: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Open-label Study of Subcutaneous Secukinumab to Evaluate Efficacy and Safety in Patients With Plaque Psoriasis Who Had Inadequate Response to Cyclosporine A (NCT02547714), a non-randomized phase 4 study. The primary outcome is Percentage of Participants Who Achieved ≥ 75% Psoriasis Area and Severity Index (PASI 75).

2. Clinical Question

The question is focused on a clinical response threshold at a specified assessment time, rather than on a comparison between treatments. PASI combines psoriasis lesion severity and affected body area into a score. The study also lists secondary measures concerning PASI response thresholds, change in PASI, investigator assessment, and dermatology-related quality of life.

Because the study was open-label and had no randomized comparator, its results would describe outcomes among participants treated in this study. They would not, by themselves, establish how those outcomes compare with what would have occurred under another treatment or without study treatment. The registry record gives the study objective and the endpoint definition, but the posted primary result is not reported in the registry record.

3. Trial Design

The registry identifies this as a Phase 4, multicenter, open-label study of subcutaneous secukinumab in people with plaque psoriasis who had an inadequate response to cyclosporine A. It was non-randomized and used a single-group model. The record lists enrollment as 34. The study status is completed.

Participants received secukinumab 300 mg by subcutaneous injection, administered as two 150 mg injections on Day 1 and at Weeks 1, 2, 3, 4, 8 and 12. The primary endpoint was assessed at Week 16. The registry gives the start date as 2015-06-16 and the primary completion date as 2016-05-02.

Open-label means that treatment was not masked in the study design. With no randomized comparator, the study can describe the outcomes recorded in its treated group, but it cannot make a like-for-like comparison with a concurrent control group. Changes over time could reflect treatment and other influences; the design alone cannot separate those explanations.

The stated primary analysis population was the full analysis set, defined in the registry as participants who received at least one dose of study drug. The enrollment figure and the definition of that analysis population are reported, but the primary outcome’s analyzed numerator and denominator are not reported in the registry record. The record also does not report a detailed statistical analysis plan, the method used to handle missing endpoint measurements, or any interim analysis plan.

Secondary outcomes listed in the record include mean percent change from baseline in PASI and DLQI scores, PASI 50 and PASI 75 response, PASI 90 and IGA 0 or 1 response, and the percentage achieving DLQI 0 or 1. The record lists six outcome measures overall. Their results are not included in the registry record for this analysis.

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: The overall treatment period consisted of a 4 week induction period (Day 1 and weeks 1, 2, 3 and 4) and a 12 week maintenance period (weeks 8 and 12). All participants entered and completed both periods.

Overall Study

Analysis population for the primary outcome, as defined in the registry: The full analysis set, which included all participants who received at least one dose of study drug, was analyzed.

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 Percentage of Participants Who Achieved ≥ 75% Psoriasis Area and Severity Index (PASI 75), measured over Week 16.

The primary endpoint is the percentage of participants achieving PASI 75 at Week 16. PASI is a composite measure that combines the severity of psoriasis lesions with the extent of affected skin. The assessment considers erythema, induration and desquamation, alongside the estimated proportion of skin involved across the head, arms, trunk and legs. The resulting PASI score ranges from 0, indicating no disease, to 72, indicating maximal disease.

PASI 75 is a response threshold: a participant qualifies by achieving at least 75% improvement from baseline in PASI. Reporting a percentage at this threshold makes the outcome interpretable as the proportion of the analysis population meeting a prespecified level of change, rather than only reporting an average score change. It does not show how far above the threshold each responder improved, or how much the score changed for participants who did not meet it.

The endpoint is specified for Week 16, so its interpretation depends on the assessment at that time. The registry record identifies the measure, threshold, timeframe and full analysis set definition. It does not report the observed percentage, responder count, denominator used for the result, or a measure of uncertainty such as a confidence interval.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry identifies the main outcome as a percentage of participants meeting a binary response criterion. For this endpoint, each participant is classified as achieving PASI 75 or not achieving PASI 75 at Week 16. The percentage is ordinarily based on the number meeting the criterion relative to a defined analysis denominator. The registry record states that the full analysis set included participants who received at least one dose, but it does not report the endpoint numerator or denominator.

What does PASI 75 represent?

PASI is a composite clinical score that combines the extent of affected skin with lesion severity. Its components include estimates of affected area and assessments of erythema, induration and desquamation. PASI 75 translates change in that score into a responder definition: at least 75% improvement from baseline. This threshold can make a result easier to describe as the share of participants crossing a defined level of improvement. It also simplifies a continuous change into a yes-or-no classification, so it does not preserve all information about the amount of change within either response category.

The endpoint is assessed at Week 16. A result at a specified time provides a time-specific description, not a complete account of the course of response before or after that assessment. The registry record does not provide a time course for the primary endpoint or the observed Week 16 response.

Why does the design affect the analysis?

A single-group study has no concurrent control group. Its main endpoint can be summarized within the treated group, but there is no randomized between-group contrast to estimate a treatment difference. Randomization, in general, helps make groups comparable on average with respect to measured and unmeasured characteristics. Without randomization and a comparator, changes from baseline may have multiple possible explanations, and the design cannot distinguish them using a controlled treatment contrast.

Open-label means treatment masking was absent. In general, knowledge of treatment can influence participant reporting, investigator assessment, decisions about follow-up, or other aspects of measurement and care. The degree to which this affects any particular result cannot be determined from the design description alone.

What does uncertainty mean for a percentage?

A percentage calculated from a study population is an estimate of the response proportion in that population under the study’s assessment and analysis procedures. A confidence interval is a general statistical tool for expressing uncertainty around an estimate. Its width depends on the amount of information and the statistical method. The registry entries do not include the PASI 75 estimate, a confidence interval, or a standard error, so the precision of the primary result cannot be evaluated.

A hypothesis test, in general, evaluates data against a specified null hypothesis under stated assumptions. A p-value is not a measure of clinical importance and does not provide the probability that a treatment works. The registry record does not report a primary endpoint p-value, a null hypothesis for the primary analysis, or the full analysis plan. No inferential conclusion about the primary endpoint can therefore be drawn from the record alone.

How should the planning assumptions be read?

The registry’s sample-size assumptions describe a planning illustration based on an observed effect, with a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. The stated effect to detect is a fraction of the observed effect. These are planning assumptions, not observed study outcomes and not observed power. In general, sample-size illustrations show how a hypothetical design might be sized under chosen assumptions; they do not establish that a study was designed or conducted that way.

The stated equal-allocation, two-arm planning setup does not match the recorded single-group study design. It should therefore not be read as evidence that this trial had two arms or a randomized comparison. The record does not report the trial’s own sample-size justification or statistical plan, and no numerical planning results are reported in the registry record. Time-to-event illustrations are described in the registry assumptions as totals of events, while other illustrations are described as participants per arm; this study’s primary endpoint is a percentage, not a time-to-event outcome.

What cannot be recovered from the record?

The registry entries do not give the primary response count, endpoint denominator, confidence interval, or hypothesis-test result. They also do not state how missing Week 16 observations were handled, whether the analysis adjusted for any covariates, or whether a sensitivity analysis was performed. These details matter because the choice of analysis population, missing-data handling and statistical model can affect the estimate and its uncertainty. Without them, the endpoint’s numerical result and robustness cannot be assessed.

10. Exact Estimates for Each Arm

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

R code and output

arm    <- c("Secukinumab (AIN457) 300 mg")
n      <- c(34)
events <- c(28)
for (i in seq_along(n)) {
  ci <- binom.test(events[i], n[i])$conf.int          # Clopper-Pearson exact interval
  cr <- qbeta(c(0.025, 0.975), 1 + events[i], 1 + n[i] - events[i])   # Bayesian, uniform Beta(1,1) prior
  wi <- (function(x, n) { p <- x / n; z <- qnorm(0.975); d <- 1 + z^2 / n
    c((p + z^2 / (2 * n) - z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d, (p + z^2 / (2 * n) + z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d) })(events[i], n[i])
  cat(sprintf("ARM|%s|%d|%d|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f\n", arm[i], n[i], events[i], 100 * events[i] / n[i],
              100 * ci[1], 100 * ci[2], 100 * wi[1], 100 * wi[2], 100 * cr[1], 100 * cr[2]))
}

ARM  Secukinumab (AIN457) 300 mg  34  28  82.4  65.5  93.2  66.5  91.7  66.4  91.6

11. Multiplicity, Missing Data and Analysis Populations

The registry lists six outcome measures, including the primary PASI 75 endpoint and secondary measures of PASI change and response, investigator assessment, and dermatology-related quality of life. When a study evaluates multiple outcomes, multiplicity is a general statistical concern: the chance of finding an apparently notable result can increase when many hypotheses are tested. A prespecified strategy may define which outcomes are confirmatory and how statistical error is controlled. The registry record does not report a multiplicity adjustment or a hierarchy for interpreting the outcomes.

The registry entries list zero analysis records. This does not supply a statistical plan or clarify how results for the listed outcomes were analyzed. The primary endpoint’s numerical result, inferential statistics and uncertainty measure are not reported in the registry record.

The full analysis set is described as including participants who received at least one dose of study drug. The record does not report the number with an evaluable Week 16 PASI assessment, the endpoint denominator, or how missing measurements were handled. In general, missing-data decisions can affect both the estimated response percentage and its uncertainty, especially when the likelihood of a missing assessment is related to participants’ outcomes. The registry record does not state whether any imputation, nonresponder rule, or sensitivity analysis was used.

Enrollment and the stated analysis-population definition do not by themselves establish that every enrolled participant contributed an observed primary endpoint. No assumptions about missingness or analysis exclusions can be inferred from the available record.

12. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 2% reporting threshold.

Most frequent non-serious adverse event terms

For the entire period, the registry reports 34 participants at risk for serious adverse events and zero affected by serious adverse events. For other adverse events, it reports 34 at risk and 24 affected. For the induction period, it reports 34 at risk for serious adverse events and zero affected; it reports 34 at risk and 10 affected by other adverse events.

These figures are counts of participants affected, as represented in the registry’s adverse-event record. They are period-specific summaries, and the induction period is part of the study’s recorded follow-up; the period counts should not be added together. The record does not provide serious adverse event terms, and the listed top serious-event terms are empty. The death count is not reported in the registry record.

A recorded count of zero means no affected participants are listed for that category and period in the registry record. It does not establish that no event could have occurred outside the recorded definitions or reporting process. The figures also do not describe severity, duration, timing, relationship to treatment, or individual participant histories. These are descriptive safety data, not a comparison with an untreated or control group.

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

The registry record establishes the study’s objective, design, endpoint definition and some adverse-event counts. It identifies a Week 16 PASI 75 response as the primary outcome in participants with plaque psoriasis who had an inadequate response to cyclosporine A. It also describes subcutaneous secukinumab administration and defines the full analysis set as participants who received at least one dose.

The record does not report the primary endpoint result. It therefore does not show the percentage achieving PASI 75, how many participants met the threshold, or how precisely any response estimate was determined. The endpoint definition and the fact that the study was completed cannot substitute for the missing outcome result. Secondary outcome results are likewise not reported in the registry entries.

Even if an observed response percentage were available, this single-group, non-randomized, open-label design would describe outcomes in the study group rather than provide a randomized comparison. Without a control group, observed change cannot be separated from other possible influences through a between-group contrast. The study design therefore does not support a like-for-like estimate against another treatment or control condition.

The adverse-event figures show that the record lists zero participants affected by serious adverse events during both the entire period and induction, and lists participants affected by other adverse events in both periods. They do not provide a full account of event types or establish comparative safety. The death count is not reported in the registry record.

Overall, the available information is useful for understanding what was studied and how the primary response was defined. It is not enough to determine the observed PASI 75 response or its statistical precision, and it does not support a causal comparison with an alternative treatment.

14. Why This Trial Matters Statistically

This study illustrates why a trial’s design and its posted results need to be read together. The registry gives a clear clinical endpoint: the percentage achieving PASI 75 at Week 16. It also specifies a single-group, open-label, non-randomized design. Those features determine what kinds of conclusions the study could support even if the endpoint estimate were available.

A responder threshold offers a straightforward summary, but it compresses a continuous score into a classification. The percentage meeting the threshold would not describe the full distribution of PASI changes or show how close nonresponders came to the cutoff. The registry’s listed secondary outcomes include measures that could describe other aspects of response and quality of life, but their results are not reported in the registry record.

The missing primary result is a central limitation for statistical interpretation. Without the observed proportion, its analysis denominator and a measure of uncertainty, readers cannot assess the magnitude or precision of the primary outcome. The record’s enrollment count does not replace these quantities.

The sample-size assumptions also illustrate the distinction between hypothetical planning and the design actually recorded. The planning description refers to equal allocation between two arms, whereas the trial is recorded as single-group. A planning illustration should not be mistaken for evidence that the study had a control arm or for a measure of observed power.

For clinical research readers, the key statistical lesson is to separate endpoint definition, design, observed estimate and uncertainty. The registry supplies the first two, but the primary estimate and its precision are not reported. That distinction prevents the design description or the completion status from being mistaken for evidence about the size of the endpoint result.

15. Limitations

• The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
• Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.

The primary limitation for interpreting efficacy is that the PASI 75 result is not reported in the registry record. The responder count, percentage, analysis denominator and precision estimate are also absent. Without these, the primary outcome cannot be quantified.

The single-group, non-randomized design has no concurrent control for a treatment comparison. Open-label conduct means masking was absent. These design characteristics limit causal interpretation and may affect assessment or reporting; the registry record does not establish the influence of any such effects on the outcomes.

The full analysis set is defined by receipt of at least one dose, but the number with a Week 16 assessment and the handling of missing data are not reported in the registry record. The record also does not provide a detailed statistical plan, any multiplicity strategy, or information about interim analyses. The trial’s sample-size justification is not reported in the registry record.

Although several secondary outcomes are listed, their results are not included in the available the registry entries. The adverse-event information is limited to period-specific counts. Serious event terms are not listed, and the death count is not reported in the registry record. The record does not give further detail about the type, timing, severity or treatment relationship of the reported other adverse events.

These limitations mean the registry information supports a description of the study design and planned primary measure, but not a complete statistical assessment of efficacy, precision, missingness or safety.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Open-label Study of Subcutaneous Secukinumab to Evaluate Efficacy and Safety in Patients With Plaque Psoriasis Who Had Inadequate Response to Cyclosporine A — NCT02547714.
• Registry record last updated 2017-09-11; status last verified 2017-08.
• Results first posted 2017-06-27.
• Data retrieved from ClinicalTrials.gov on 2026-11-09.
• Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.

19. Record Summary

NCT02547714 is a completed Phase 4, multicenter, open-label, non-randomized, single-group study of subcutaneous secukinumab in plaque psoriasis among participants with an inadequate response to cyclosporine A. Enrollment is listed as 34. Participants received 300 mg as two 150 mg injections on Day 1 and at Weeks 1, 2, 3, 4, 8 and 12.

The primary endpoint was the percentage achieving PASI 75 at Week 16, analyzed in a full analysis set defined as participants who received at least one dose. The registry record does not report the primary result or its precision. Adverse-event records list zero participants affected by serious adverse events in the entire and induction periods; other adverse events affected 24 participants during the entire period and 10 during induction. The death count is not reported in the registry record.