This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for Monocyte Biomarkers in Moderate to Severe Plaque Psoriasis Subjects Treated With Apremilast (NCT03442088), a na phase 2 study. The primary outcome is The Primary Outcome Measure Will be to Evaluate Change in Aberrant Inflammatory Profiles of Activated Blood Monocytes (Aberrant-monocyte Endotype Patients (AM-endotype)..
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT03442088 |
| Phase | Phase 2 |
| Condition | Plaque Psoriasis |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 28 |
| Arms in the primary outcome | n/a |
| Lead sponsor | University Hospitals Cleveland Medical Center |
| Results posted | Yes |
2. Clinical Question
Population
People with moderate to severe plaque psoriasis and the AM-endotype, identified by an elevated level of at least one specified monocyte biomarker. The registry description defines elevation as >150% of normal for intermediate monocytes, circulating monocyte doublets, or circulating monocyte-platelet aggregates.
Intervention
Apremilast, described in the registry summary as standard dosing, continued through Week 16. The record does not specify the dose.
Comparator
There was no separate comparator group. The study was open label and single group; the primary outcome compares each participant’s biomarker with that participant’s own baseline value.
Primary question
How did the selected abnormal monocyte biomarker change, in relative percent terms, from baseline to Week 16 during apremilast treatment? The planned analysis focused on the median percent reduction across participants. Numerical primary-outcome results are not reported in the registry record.
This is a within-participant change question, not a question about how apremilast compares with placebo or another treatment. For each participant, the study identified one target biomarker from intermediate monocytes, monocyte doublets, or platelet doubles. The relative change in that selected measure was then the basis for the primary outcome. The registry describes the outcome as change in aberrant inflammatory profiles of activated blood monocytes in people with the AM-endotype.
The study also listed changes in serum myeloperoxidase, TNF Alpha, IL-17, and tissue factor as secondary outcomes. The registry record does not include numerical results for these outcomes. The primary question is therefore best understood as an intended biomarker assessment over time, rather than as a reported estimate of treatment effect or a comparison between treatment strategies.
3. Trial Design
NCT03442088, titled “Monocyte Biomarkers in Moderate to Severe Plaque Psoriasis Subjects Treated With Apremilast,” is recorded as a Phase 2, completed study sponsored by University Hospitals Cleveland Medical Center. The record gives a start date of 2018-06-01 and a primary completion date of 2021-09-30. Enrollment is listed as 28.
The design is open label, single group, and has no masking. Allocation is listed as NA, and there is no randomized control group. Participants with psoriasis and the AM-endotype received apremilast, with follow-up through Week 16. Because all treated participants were in the same group, comparisons of the primary outcome are based on change from baseline within participants rather than on differences between independently assigned groups.
The registry’s brief summary describes approximately 25 patients and says that participants would have 4 monthly individual blood draws during treatment. The arm description instead says that 5 monthly individual blood draws would be used. These descriptions do not agree; the registry record does not resolve the discrepancy. The record also does not give a complete visit schedule beyond the stated baseline and Week 16 primary-outcome time points.
The study focused on people identified as having the AM-endotype through elevated intermediate monocytes, circulating monocyte doublets, or circulating monocyte-platelet aggregates. Each participant was assigned one target biomarker for the primary analysis. The record describes the intervention as apremilast and the study as a pilot, but does not report a protocol rationale for the single-group design, the choice of enrollment target, or the sampling schedule. A comparator-based treatment effect cannot be estimated from this design.
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
| Stage | Apremilast for Treatment of Psoriasis With the AM-endotype |
|---|---|
| STARTED | 28 |
| COMPLETED | 23 |
| NOT COMPLETED | 5 |
Reasons for not completing this period:
| Reason | Apremilast for Treatment of Psoriasis With the AM-endotype |
|---|---|
| Adverse Event | 1 |
| Lack of Efficacy | 2 |
| Lost to Follow-up | 2 |
Analysis population for the primary outcome, as defined in the registry: 1 subject missed interim visits, so data was not analyzed for this one participant.
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.
| Characteristic | Unit | Apremilast for Treatment of Psoriasis With the AM-endotype |
|---|---|---|
| Participants analysed | 28 | |
| Age, Continuous | years | 44.7 (SD 12.6) |
| Sex: Female, Male: Female | Participants | 10 |
| Sex: Female, Male: Male | Participants | 18 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 0 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 28 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 |
| Race (NIH/OMB): Asian | Participants | 0 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 |
| Race (NIH/OMB): Black or African American | Participants | 5 |
| Race (NIH/OMB): White | Participants | 22 |
| Race (NIH/OMB): More than one race | Participants | 1 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 |
6. Primary Endpoint
The registry lists the primary outcome as The Primary Outcome Measure Will be to Evaluate Change in Aberrant Inflammatory Profiles of Activated Blood Monocytes (Aberrant-monocyte Endotype Patients (AM-endotype)., measured over Baseline, Week 16.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Deviation |
| Unit | Percent change |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is the relative percent reduction in one selected monocyte biomarker from baseline to Week 16. For each participant, the selected target was the abnormal biomarker among intermediate monocytes, monocyte doublets, or platelet doubles. The endpoint thus allows different participants to have different target biomarkers; it does not describe a single identical laboratory measure for every participant.
The registry explains the calculation as a relative reduction from the participant’s baseline value. Its example states that a change from 1.5% to 1.2% corresponds to a 20% reduction. That example illustrates the scale of the measure, not a reported study result. The record says that the median and other summary statistics of participants’ percent changes would be computed, and that a Wilcoxon signed-rank test would assess the null hypothesis that the median percent change is 0.
A relative change can express how far a biomarker moved from its own starting value, which is useful when the primary interest is within-person change. But participants’ endpoints may represent different biomarkers, and the registry does not report how results were summarized across those target types. The purpose and interpretation of this endpoint are therefore limited to the intended biomarker-change analysis. Numerical endpoint estimates and their uncertainty are not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record describes the primary outcome and the intended analysis, but numerical primary-outcome results are not reported in the registry record. In particular, no observed median percent reduction, distribution of participant changes, test statistic, p-value, or confidence interval is included in the registry record for this analysis. The direction and magnitude of the primary biomarker change therefore cannot be characterized from the registry record.
The planned endpoint is a within-participant comparison of baseline with Week 16. It is not a comparison of apremilast with an untreated or alternative-treatment group. Even if a numerical change were available, a single-group before-and-after analysis would describe change over time among observed participants, not isolate the effect of treatment from other explanations for change. The registry record does not report a control group or a causal comparison.
The outcome uses a participant-specific target selected from several types of monocyte measures. Consequently, a pooled summary would combine changes in selected biomarkers rather than track one common biomarker across every participant. The record does not report results separated by biomarker type, so it is not possible to assess whether changes were consistent across the different target measures.
The primary outcome description says that one participant missed interim visits and was not analyzed for this outcome. It does not describe the handling of missing measurements for any other outcome, or whether other participants had incomplete data. The registry record also does not report whether the planned signed-rank test was performed, whether any analysis differed from the plan, or how the stated summaries were calculated in the final results.
Safety counts are reported separately: the record lists no serious adverse events and no deaths, while 13 participants are recorded as affected by other adverse events. These counts describe the registry’s recorded safety categories; they do not establish whether an event was caused by treatment. The record does not provide event descriptions, severity or duration details, or the timing of events. The meaning of the counts is therefore bounded by the categories and follow-up information recorded.
Overall, the available information supports a description of the study design, intended biomarker endpoint, and recorded safety counts, but not an assessment of the observed primary biomarker result. Any planning illustration based on an observed effect should be distinguished from observed power: it is a hypothetical sample-size calculation under stated assumptions, not evidence about the outcome or the probability that the study detected an effect. The registry record does not include the numerical planning estimates in the registry record.
9. Statistical Methods Explained
The primary analysis was described as a paired, within-participant assessment: each person’s Week 16 value is compared with that person’s baseline value. Pairing is appropriate to the stated question because the endpoint is defined from an individual’s starting measurement, rather than from a contrast between separate groups. The registry specifies relative percent reduction as the quantity summarized, and identifies the median and other summary statistics as planned descriptions of those individual changes.
What does relative percent reduction represent?
General explanation: a relative change expresses movement in relation to a starting value. It differs from an absolute change, which expresses the raw difference on the measurement scale. The registry uses a percent-reduction convention and includes an example in which a baseline value of 1.5% changes to 1.2%, corresponding to a 20% reduction. That example clarifies the calculation but is not an observed result from the study. The record does not state how values at or near a possible measurement limit were handled, or whether any data transformations were used.
Why report the median?
General explanation: the median describes the middle of a distribution and is less sensitive than the mean to unusually large or small observations. This can be useful when individual changes are unevenly distributed. The registry says that the median and other summary statistics of percent changes would be computed. Although the endpoint fields also name a mean parameter and standard deviation, the outcome description specifically discusses the median and a signed-rank test. The registry record does not explain how those descriptions relate to the reported analysis, or provide numerical summaries.
What does the signed-rank test assess?
General explanation: the Wilcoxon signed-rank test is a nonparametric method for paired data. It evaluates whether paired changes are centered around a specified reference value, using the signs and ranks of the changes. In this study, the stated null hypothesis is that the median percent change is 0. The registry record identifies this test but does not report the test statistic, p-value, confidence interval, or a final result. A test of this kind does not by itself quantify the size or practical importance of a biomarker change; descriptive estimates and their uncertainty are also important.
What would a confidence interval add?
General explanation: a confidence interval communicates the precision of an estimate by giving a range of values compatible with the data under the method’s assumptions. A narrow interval generally indicates greater precision than a wide interval, while an interval spanning the null value may be compatible with a range of effects that includes no change. No confidence interval for the primary endpoint is reported in the registry record, so its precision cannot be assessed from the available information.
How should the sample-size illustrations be read?
The planning assumptions describe illustrations based on an observed effect, two-sided significance level 0.05, equal allocation between two arms, and a normal approximation; the effect to detect is described as a fraction of the observed effect. The record says that non-time-to-event planning results are expressed as participants per arm. These assumptions do not describe the actual single-group design, which has no two-arm allocation. A planning illustration is not observed power and does not demonstrate that the study had a particular probability of detecting an effect. Numerical planning estimates are not reported in the registry record available for this analysis, and the registry does not state that these assumptions were part of the trial’s original design.
The statistical interpretation is further limited by endpoint construction. Participants could have different target biomarkers, and the record does not describe a model that accounts for those differences. It also does not report whether the final analysis used all available paired measurements, how incomplete pairs were handled beyond the one participant noted, or whether assumptions and diagnostics were assessed. Those details are not reported in the registry record and should not be inferred from the named test alone.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists several secondary outcomes: change in serum myeloperoxidase, TNF Alpha, IL-17, and tissue factor. It also reports 9 outcome measures and 5 analyses. However, the record does not describe a multiplicity adjustment, a hierarchy among outcomes, or a strategy for controlling the chance of false-positive findings when multiple outcomes or analyses are considered. Those details are not reported in the registry record. The number of listed outcomes alone does not show whether, or how, the analyses were adjusted.
The primary outcome description notes that one participant missed interim visits and that data for this participant were not analyzed for the primary outcome. It does not say whether the participant had a baseline measurement, how the missed visits occurred, or whether any missing values were imputed. Nor does it explain the analysis population for secondary outcomes or other analyses. The record therefore supports describing this exclusion for the primary outcome, but not extending it to every analysis.
Missing-data methods matter because an analysis using only participants with usable paired values can differ from one that makes assumptions about unobserved values. General explanation: complete-case analysis summarizes the observed cases, while imputation or model-based approaches use additional assumptions about missingness and the data. The registry does not identify which broader approach was used or provide sensitivity analyses. The pattern and reasons for missing measurements are also not reported in the registry record.
The record does not report a prespecified analysis population, such as an intention-to-treat population, or explain whether the analyzed population followed another rule. It also does not report whether interim analyses were planned or conducted, or provide a statistical analysis plan. These omissions limit assessment of selective analysis and the robustness of reported findings. They do not establish that any particular method was or was not used beyond the specific missing-participant statement.
11. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| Apremilast for Treatment of Psoriasis With the AM-endotype | 0 | 28 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Apremilast for Treatment of Psoriasis With the AM-endotype | 0 of 28 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Apremilast for Treatment of Psoriasis With the AM-endotype | 13 of 28 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Apremilast for Treatment of Psoriasis With the AM-endotype |
|---|---|---|
| Nausea | Gastrointestinal disorders | 1 of 28 |
| Diarrhea | Gastrointestinal disorders | 1 of 28 |
| Sinus/viral infection | Infections and infestations | 1 of 28 |
| Arthroscopic procedure | Surgical and medical procedures | 1 of 28 |
| Contact dermatitis to watch | Skin and subcutaneous tissue disorders | 1 of 28 |
| Psoriasis flare | Skin and subcutaneous tissue disorders | 1 of 28 |
| Hyponatremia | Metabolism and nutrition disorders | 1 of 28 |
| Cough | Respiratory, thoracic and mediastinal disorders | 1 of 28 |
| COVID | Infections and infestations | 1 of 28 |
| Headache | General disorders | 1 of 28 |
The registry lists 28 participants at risk for serious adverse events, with 0 affected, and 0 deaths. It also lists 28 participants at risk for other adverse events, with 13 affected. These are the recorded counts for the apremilast study group. They should be read as separate registry categories, not combined into a single event count.
The absence of recorded serious adverse events in these fields does not establish that no adverse experiences of any kind occurred: the other-adverse-event category has 13 affected participants. Conversely, the count for other adverse events does not say how many events occurred, since the registry field records participants affected. No serious adverse event terms are listed in the record.
The registry information does not describe the specific other adverse events, their severity, duration, timing, or whether investigators considered them related to apremilast. It also does not give a detailed safety follow-up window or explain how events were collected. The counts therefore describe what is recorded in the registry categories, not a complete characterization of safety or a comparison with another group.
12. What the Result Does, and Does Not, Mean
The study is designed to describe change in a selected monocyte biomarker between baseline and Week 16 among people with plaque psoriasis and the AM-endotype who received apremilast. The primary analysis is intended to summarize participant-level relative percent reductions and test whether their median differs from 0. This is a biomarker question within a single group, not a randomized comparison of treatment strategies.
The registry record does not report numerical primary-outcome results. It therefore cannot establish the observed direction, size, or precision of the biomarker change. It also does not report the numerical results for the secondary outcomes. The intended endpoint and test describe what investigators planned to evaluate; they are not substitutes for estimates from the observed data.
Even if the change estimates were reported, the open-label, single-group structure would limit causal interpretation. A change between baseline and follow-up can be described in the observed group, but without a comparator it cannot distinguish treatment-associated change from other influences over time. The registry record does not provide a basis for comparing apremilast with placebo or another intervention.
The individualized target also matters. A pooled endpoint may combine changes in different biomarkers, and the record does not report biomarker-specific results. Without those results, consistency across target types cannot be judged. The missing interim visits for one participant and the absence of a fuller missing-data description further limit assessment of how complete the primary analysis was.
These limitations do not invalidate the study’s intended exploratory biomarker question. They define what can be concluded from the information recorded: the study design, endpoint definition, planned statistical test, and safety counts can be described, but the observed primary result and its uncertainty are not reported in the registry record. No conclusion about clinical benefit should be drawn from the endpoint description or from a planning calculation.
13. Why This Trial Matters Statistically
This trial is statistically notable for its participant-specific endpoint. Rather than applying one identical abnormal monocyte measure to everyone, the registry describes selecting one target biomarker for each participant from several possible measures. The resulting outcome is a relative change in that selected target. That approach fits an individualized biomarker question, but it also means that a pooled summary may combine different underlying measures.
The single-group design makes the baseline-to-Week 16 pairing central to the analysis. Pairing accounts for each participant’s own starting value when describing change, but it does not create a concurrent control group. The planned signed-rank test addresses the distribution of paired changes relative to 0; it does not answer a between-treatment question.
The registry also illustrates why outcome definitions and result reporting need to be read together. The endpoint description provides a clear example of relative reduction and names a statistical test, but numerical estimates and uncertainty are not reported in the registry record. Without those results, readers cannot judge the magnitude, variability, or precision of the observed biomarker changes.
Finally, the record documents issues relevant to reproducibility: two different descriptions of the number of monthly blood draws, one participant not analyzed for the primary outcome after missing interim visits, and no reported multiplicity or broader missing-data strategy. These details make the trial useful for understanding the challenges of analyzing a small pilot biomarker study, while also limiting how fully its analysis can be evaluated from the registry record.
14. 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 principal limitation for interpretation is that numerical efficacy results are not reported in the registry record. No primary estimate, uncertainty interval, test result, or numerical secondary-outcome result is included in the registry record for this analysis. As a result, the observed biomarker findings cannot be described.
The design has no control group and is open label. Changes from baseline to Week 16 are therefore within-group observations and cannot isolate treatment effects from other changes over time. The record does not report a randomized comparison, masking, or a comparator treatment.
The primary endpoint may represent different measures for different participants. The record does not give the number of participants in each biomarker category, biomarker-specific summaries, or a method for assessing whether results differ by target. It also contains inconsistent descriptions of the planned blood-draw schedule: the brief summary says 4 monthly draws, while the arm description says 5 monthly draws. The registry does not resolve this discrepancy.
For the primary outcome, one participant is stated to have missed interim visits and not been analyzed. The record does not provide a complete account of missingness, the analysis population, imputation, or sensitivity analyses. It also does not report a multiplicity strategy despite listing multiple outcomes and analyses. Sample-size justification, the original statistical analysis plan, and interim-analysis details are not reported in the registry record.
Safety reporting is limited to counts by broad category. Event descriptions, severity, timing, duration, and relationship to treatment are not given. These limitations constrain assessment of the study’s observed outcomes and the reproducibility of its analysis.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Monocyte Biomarkers in Moderate to Severe Plaque Psoriasis Subjects Treated With Apremilast — NCT03442088.
- Registry record last updated 2023-01-20; status last verified 2022-12.
- Results first posted 2023-01-20.
- 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.
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18. Record Summary
NCT03442088 is a completed Phase 2, open-label, single-group study sponsored by University Hospitals Cleveland Medical Center. The record lists enrollment of 28 and dates of 2018-06-01 for study start and 2021-09-30 for primary completion. Participants with plaque psoriasis and the AM-endotype received apremilast through Week 16.
The primary outcome was relative percent reduction in one selected monocyte biomarker from baseline to Week 16, with the median percent change assessed using a Wilcoxon signed-rank test. The record notes that one participant missed interim visits and was not analyzed for the primary outcome. Numerical primary and secondary outcome results are not reported in the registry record.
Safety fields list 0 serious adverse events, 13 participants affected by other adverse events, and 0 deaths. The record does not provide event descriptions or a detailed statistical analysis plan.