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 Single Center, Open Label, Study of Preparation H on Erythema in Relapsing MS Patients Treated With PLEGRIDY (NCT02665221), a randomized phase 4 study. The primary outcome is Patient Erythema Self-Assessment (PSA) Score 6 hr After Application of Preparation H to First Injection Site Erythema Compared to Baseline PSA Score of Injection Site Erythema at Least 2 Hours After PLEGRIDY Injection..
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT02665221 |
| Phase | Phase 4 |
| Condition | Multiple Sclerosis |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Double |
| Enrollment | 30 |
| Arms in the primary outcome | n/a |
| Lead sponsor | NYU Langone Health |
| Results posted | Yes |
2. Clinical Question
Population
Relapsing multiple sclerosis patients treated with PLEGRIDY (peginterferon beta-1a) at a single center. The registry lists an enrollment of 30.
Intervention
Topical Preparation H Maximum Strength Cream containing phenylephrine, applied to injection-site erythema after a PLEGRIDY injection.
Comparator
No topical treatment of the injection-site erythema. The registry describes a no-treatment arm and a topical Preparation H arm.
Primary question
Was the Patient Erythema Self-Assessment score at 6 hours after Preparation H application different from the baseline score, assessed at least 2 hours after PLEGRIDY injection? The registry reports that the study was terminated, the logpad was defective, data were not collected, and no data were analyzed; therefore, it does not answer this comparison.
The intended question concerns the severity of injection-site erythema as assessed by patients. The primary endpoint description specifies a score after topical application and a baseline score following injection. It does not provide a score scale, its range, or the direction that would represent greater erythema. Nor does the record report observed scores or an estimated treatment effect.
The study also listed injection-site erythema width and the number of patients experiencing erythema, itching, and pain as secondary outcomes. Their results are not reported in the registry record. The clinical question is therefore clear from the trial description, but the registry does not contain outcome data that establish whether the intervention changed erythema or related symptoms.
3. Trial Design
The registry identifies this as a randomized, parallel-group, Phase 4 study at a single center. The listed enrollment is 30. The treatment comparison was topical Preparation H versus no topical treatment after injection-site erythema associated with PLEGRIDY. The registry gives a study start of 2015-07 and a primary completion date of 2016-09, and lists the study status as terminated.
The description of masking is inconsistent. The title and study description call the study open label, while the registry's masking entry says double. The record does not explain this discrepancy, identify who may have been masked, or clarify which description reflects the conduct of the study. It is therefore not possible to characterize masking more precisely from the registry record.
The registry lists a control group and a treatment group. In the safety entries, each group has 15 participants at risk for serious adverse events and other adverse events. These safety denominators are recorded separately from the trial's enrollment field and do not provide an outcome analysis. The arm descriptions themselves are blank, although the intervention entries identify a no-treatment arm and a topical Preparation H arm.
The primary outcome was intended to compare a Patient Erythema Self-Assessment score after application with a baseline score after injection. The record says the study was terminated because the logpad used by subjects was defective; data were not collected and no data were analyzed. This means the randomized design did not produce a reported primary-outcome comparison in the registry.
The registry lists four outcome measures and names secondary assessments of erythema width and injection-site reactions. It does not report results for those assessments. The record also does not report a statistical analysis plan, a sample-size justification, or an account of how termination affected any other measurements.
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 | Control Group | Treatment Group |
|---|---|---|
| STARTED | 15 | 15 |
| COMPLETED | 0 | 0 |
| NOT COMPLETED | 15 | 15 |
Analysis population for the primary outcome, as defined in the registry: Study was terminated. Logpad used by subjects was defective and data was not collected. No data 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.
| Characteristic | Unit | Control Group | Treatment Group | Total |
|---|---|---|---|---|
| Participants analysed | 15 | 15 | 30 | |
| Age, Categorical: <=18 years | Participants | 0 | 0 | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 15 | 15 | 30 |
| Age, Categorical: >=65 years | Participants | 0 | 0 | 0 |
| Sex: Female, Male: Female | Participants | 12 | 12 | 24 |
| Sex: Female, Male: Male | Participants | 3 | 3 | 6 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Asian | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Black or African American | Participants | 1 | 5 | 6 |
| Race (NIH/OMB): White | Participants | 14 | 9 | 23 |
| Race (NIH/OMB): More than one race | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 | 1 | 1 |
| Region of Enrollment: United States | Participants | 15 | 15 | 30 |
6. Primary Endpoint
The registry lists the primary outcome as Patient Erythema Self-Assessment (PSA) Score 6 hr After Application of Preparation H to First Injection Site Erythema Compared to Baseline PSA Score of Injection Site Erythema at Least 2 Hours After PLEGRIDY Injection., measured over 6 Hours.
| Element | Registry entry |
|---|---|
| Result type | N/A |
| Measure of spread | not applicable |
| Unit | not stated |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is the Patient Erythema Self-Assessment (PSA) score for the first injection-site erythema, measured 6 hours after application of Preparation H. It was intended to be compared with the baseline PSA score for injection-site erythema, assessed at least 2 hours after PLEGRIDY injection.
A patient-reported score can capture the participant's own assessment of a symptom or visible reaction. In general, such an endpoint is useful when the experience being assessed is not fully represented by a clinical or laboratory measurement. The registry does not describe the PSA scale, how it is scored, what values mean, or whether a higher score indicates greater severity. Those details are needed to interpret the size and direction of a score difference.
The timing defines the intended comparison: an assessment after topical application and a baseline assessment after injection. The record does not specify further details about how the two assessments were paired or analyzed. More importantly, it states that the logpad was defective, data were not collected, and no data were analyzed. There are consequently no reported PSA values, treatment-effect estimate, or uncertainty measure. The endpoint's intended clinical meaning can be described, but its result cannot be interpreted from the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The central statistical fact is that the registry reports no primary-outcome data and no analysis. The reason given is that the logpad used by subjects was defective and data were not collected. This is not a result showing that Preparation H had no effect, nor is it evidence that the treatment and no-treatment groups were equivalent. Without recorded PSA scores, the registry cannot quantify the difference between the intended post-application and baseline assessments.
The primary endpoint was a patient erythema self-assessment score after topical application compared with baseline. The record does not provide the score scale or its interpretation, and it provides no estimate, confidence interval, or test result. A confidence interval, in general, communicates the statistical uncertainty around an estimated effect. Since there is no reported estimate, there is no interval from which to judge precision. No p-value or other inferential result is reported either.
The registry also names secondary assessments: erythema width in millimeters after application compared with baseline, and the number of patients experiencing injection-site erythema, itching, and pain. Results for these outcomes are not reported in the registry record. Their inclusion in the outcome list does not establish that measurements were available or analyzed. The record specifically describes the primary data collection failure, but does not explain the status of each secondary measure.
Safety entries list 0 serious adverse events, 0 other adverse events, and 0 deaths for the control group and the treatment group. Each group is listed with 15 participants at risk in the serious and other adverse event entries. These are the recorded counts; they do not demonstrate that no event could occur, and they do not replace an efficacy analysis. The registry does not give further details on safety surveillance or how the terminated study affected event collection.
The study status is terminated, and the listed primary completion date is 2016-09. The record does not provide a statistical analysis plan or explain whether any analyses were planned before termination. It lists no analyses. As a result, there is no basis in the registry for comparing the groups on the intended endpoint, assessing statistical significance, or determining the precision of a treatment-effect estimate.
Any planning illustrations based on an observed effect must be distinguished from trial results and from the original design. The registry describes its planning assumptions as an illustration based on the observed effect, with two-sided significance level 0.05, equal allocation, and a normal approximation. It does not report that these were the trial's own design assumptions. Since no primary outcome was collected or analyzed, the record does not provide an observed primary effect that could support a meaningful interpretation of such planning calculations.
Overall, the posted data document the trial's question, design features, termination, and recorded safety counts. They do not answer whether topical Preparation H changed injection-site erythema. The absence of an estimate is a consequence of missing primary data, not an estimate of zero effect.
9. Statistical Methods Explained
What can randomization establish?
Randomization assigns participants to trial groups by a chance-based process. In general, this is intended to make the groups comparable, on average, with respect to factors that could influence the outcome. It supports a fair treatment comparison when outcomes are collected and analyzed according to an appropriate plan. Random assignment by itself does not produce evidence about an effect: the outcomes still need to be measured, and the comparison needs to be reported.
The registry describes this study as randomized and parallel, with a no-treatment group and a topical Preparation H group. It does not report how the random sequence was generated, how assignments were concealed, or whether participants were analyzed according to their assigned groups. Those methods are not reported in the registry record. Further, the study's open-label description conflicts with the double-masking entry. The record does not resolve the discrepancy, so the effect of masking on outcome assessment cannot be evaluated from it.
What was the intended comparison?
The primary comparison was based on PSA scores for injection-site erythema. The endpoint specifies a score after application of Preparation H and a baseline score at least 2 hours after injection. A treatment-effect analysis would ordinarily estimate a contrast between outcomes under the intervention and comparator, using a prespecified method appropriate to the endpoint and design. The registry does not report such an estimate or describe the planned model or test.
The PSA scale is not described. For a score outcome, interpretation depends on the scale's properties, its valid range, and what its values represent. The record does not provide those details, so it is not possible to determine whether a particular numerical difference would be small, large, or clinically important. It also does not state whether the intended analysis would compare changes from baseline, post-application scores adjusted for baseline, or another contrast. No approach should be attributed to the investigators without a report.
Why does missing outcome collection matter?
Defective data collection prevented the primary scores from being collected, according to the registry. This is different from having measurements with a wide confidence interval or a non-significant test. With no reported primary observations, there is no observed effect to estimate and no sampling uncertainty to quantify. Statistical methods cannot recover the unrecorded patient assessments without additional information or assumptions that are not reported.
Missing outcome data can also affect the comparability intended by randomization. In general, if outcome availability differs across assigned groups or is related to outcomes, analyses restricted to observed measurements may be biased. Here, the registry does not report the pattern of missingness by group, whether any participants had usable assessments, or any method for handling missing values. It states that data were not collected and no data were analyzed. Imputation or other missing-data procedures are not reported in the registry record.
How should uncertainty be understood?
In general, a confidence interval presents a range of effects compatible with the observed data under the analysis assumptions. Its width reflects precision: a wider interval indicates less precise information. A significance test addresses compatibility of data with a specified null hypothesis, but a p-value alone does not measure effect size or clinical importance. These concepts require an estimate and usable data. The registry reports neither for the primary endpoint, so no confidence interval, significance result, or assessment of precision is available.
The outcome description includes a score and a measure of erythema width in millimeters. The appropriate summary depends on the data type and distribution. For example, a continuous measurement may be summarized with a mean when that is appropriate, while skewed or ordinal data may require other summaries or models. This is general statistical context, not a description of the analysis used in this trial. The registry does not report the score scale, distribution, outcome summaries, or analysis choices. There is therefore no basis to select or infer a particular model.
What do the planning assumptions represent?
The registry distinguishes a planning illustration from the trial's own design. Its stated assumptions include a two-sided significance level of 0.05, equal allocation between arms, and a normal approximation; the effect to detect is described as a fraction of an observed effect. Such calculations are generally used to illustrate how a planned study's size relates to an assumed effect and analysis conditions. They are not observed power, and they do not establish whether the study was adequately planned.
The record does not report a trial-specific sample-size justification or say that the illustration's assumptions were used to design this study. Because the primary outcome was not collected or analyzed, there is no reported primary effect that can be interpreted as an observed treatment effect. Any planning output should therefore be read only as an assumption-based illustration, not as evidence of efficacy, a result, or a retrospective measure of the trial's ability to detect an effect.
What analyses are reported?
The registry lists no analyses. The primary outcome description explicitly states that no data were analyzed. No statistical analysis plan, adjustment method, model, or analysis population is reported in the registry record. The secondary outcome descriptions do not substitute for results. Without analysis details and estimates, the trial cannot be reconstructed statistically from the registry entry, and no unadjusted recalculation can be made from posted outcome summaries.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists four outcome measures, including the primary PSA assessment and secondary measures concerning erythema width and injection-site reactions. It does not report analyses for these outcomes. A multiplicity plan would explain how inference is handled when several outcomes or comparisons are considered, since examining multiple results can increase the chance of a misleading positive finding. No such plan or adjustment is reported in the registry record.
The record states that the logpad was defective, data were not collected, and no data were analyzed. It does not provide outcome-specific missingness details for the listed secondary measures, so their collection status cannot be inferred from the primary-outcome explanation. No imputation method, missing-data sensitivity analysis, or other approach to incomplete measurements is reported.
The analysis populations are also not reported in the registry record. The entry does not say whether an intention-to-treat, per-protocol, or other population was planned or used. Nor does it state how participants were to be handled if outcome measurements were unavailable. These omissions matter because analysis-population choices and missing-data assumptions can affect how a randomized comparison is interpreted.
Because no analyses are listed and no primary data were analyzed, multiplicity adjustment, missing-data handling, and population definitions cannot be evaluated. This is an absence of reported inferential results, not evidence that the listed outcomes were equivalent between groups.
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 |
|---|---|---|---|
| Control Group | 0 | 15 | 0.0% |
| Treatment Group | 0 | 15 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Control Group | 0 of 15 |
| Treatment Group | 0 of 15 |
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 |
|---|---|
| Control Group | 0 of 15 |
| Treatment Group | 0 of 15 |
The registry lists 0 serious adverse events and 0 deaths in the control group, and 0 serious adverse events and 0 deaths in the treatment group. It also lists 0 other adverse events in each group. Each group is recorded as having 15 participants at risk for serious and other adverse events.
These entries are reported counts, not estimates that the risk of an event is zero. A zero count in a registry entry does not establish that an intervention is free of risk, particularly when the study was terminated and the primary data collection problem is documented. The record does not describe the duration or completeness of safety follow-up, or provide additional information about how adverse events were collected.
The counts should be read separately from the unreported erythema outcomes. They do not answer the efficacy question, and they do not supply a comparison of PSA scores or erythema width. The registry's safety figures are limited to the listed event counts and at-risk entries; broader safety conclusions are not reported.
12. What the Result Does, and Does Not, Mean
The record establishes that a randomized, parallel-group study was intended to compare topical Preparation H with no topical treatment for injection-site erythema in relapsing MS patients receiving PLEGRIDY. It identifies the intended primary measure as the Patient Erythema Self-Assessment score after application compared with baseline. It also identifies secondary assessments of erythema width and injection-site reactions.
What the record does not establish is whether Preparation H changed erythema. The primary outcome description says the study was terminated, the logpad was defective, data were not collected, and no data were analyzed. No primary estimate, uncertainty interval, or test result is reported. The secondary outcomes likewise have no reported results. There is therefore no statistical basis in this record to claim benefit, lack of benefit, or equivalence between the groups.
The safety entries record zero serious adverse events, zero other adverse events, and zero deaths in each group. These counts describe what the registry lists; they are not proof that no adverse event occurred beyond the information captured in the entry, and they do not support a broad safety conclusion. The record does not provide details needed to assess completeness of event monitoring.
The study's termination and data-collection failure limit what can be learned from its randomized design. Randomization can support causal interpretation when outcomes are adequately observed and the comparison is analyzed. It cannot compensate for unavailable endpoint data. The registry also does not clarify its conflicting open-label and double-masking descriptions, or report a statistical analysis plan.
Accordingly, the useful conclusion is about the evidence record rather than treatment effect: the intended question is documented, but the posted results do not answer it. No treatment conclusion should be drawn from the absence of a reported primary result.
13. Why This Trial Matters Statistically
This trial illustrates the difference between a planned comparison and an informative result. The registry describes random allocation to topical Preparation H or no topical treatment and specifies a patient-assessed erythema outcome. But the primary data were not collected, so the study does not yield an effect estimate. A design can be appropriate in principle and still fail to answer its question if outcome measurement does not produce analyzable data.
It also shows why outcome measurement procedures are part of the statistical design. The stated reason for termination was a defective logpad used by subjects. This collection failure left no primary scores to summarize or compare. Statistical modeling, confidence intervals, and significance tests depend on observed information; they cannot replace measurements that were never collected.
The registry also illustrates why record consistency matters. Its titles and study description call the study open label, while the masking entry says double. Without clarification, readers cannot confidently assess how treatment awareness may have affected a self-assessed endpoint. A patient-reported measure can be informative, but interpretation depends on a clear scale and reliable collection, neither of which is described in enough detail to interpret a result.
Finally, the study's listed safety counts and planning assumptions answer different questions from the primary efficacy endpoint. Zero recorded events are not an estimate of an erythema treatment effect, and a planning illustration is not an observed result. Keeping these distinctions clear prevents missing data from being mistaken for evidence of no effect and prevents design calculations from being mistaken for trial findings.
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 primary limitation is the absence of collected and analyzed PSA data. The registry attributes this to a defective logpad and states that the study was terminated. Consequently, the central treatment comparison has no reported score summaries, effect estimate, or measure of uncertainty.
Other limitations concern incomplete reporting. The PSA scale and the meaning of its values are not described, and the record does not specify a planned statistical method for the primary comparison. It does not report an analysis plan, analysis populations, missing-data procedures, or multiplicity handling. Results for the listed secondary measures are not reported in the registry record.
The record's masking information is inconsistent: the study description says open label, whereas the masking entry says double. No explanation clarifies the discrepancy. The arm descriptions are blank, and the registry does not explain whether the secondary outcome measurements were collected despite the primary data-collection failure.
Safety reporting is limited to the listed event counts and at-risk entries. Details of surveillance and follow-up are not reported. The registry also does not report a trial-specific sample-size justification. These limitations constrain both interpretation of the intended comparison and assessment of how completely the terminated study's outcomes and safety information were captured.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Single Center, Open Label, Study of Preparation H on Erythema in Relapsing MS Patients Treated With PLEGRIDY — NCT02665221.
- Registry record last updated 2018-01-18; status last verified 2017-12.
- Results first posted 2018-01-18.
- 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
The registry describes a single-center, randomized, parallel-group Phase 4 study in relapsing MS patients receiving PLEGRIDY. It compares topical Preparation H Maximum Strength Cream with no topical treatment for injection-site erythema. The listed enrollment is 30, and the study status is terminated.
The primary endpoint was the Patient Erythema Self-Assessment score after application compared with baseline. The registry states that the logpad was defective, data were not collected, and no data were analyzed. Results for the listed secondary outcomes are not reported. Safety entries list zero serious adverse events, zero other adverse events, and zero deaths in each group, with 15 participants at risk recorded for each group.
The record does not provide an interpretable treatment-effect estimate. Its description of masking is inconsistent, and an analysis plan, analysis populations, and missing-data methods are not reported.