CellFX System for the Treatment of Cutaneous Non-Genital Warts: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for CellFX System for the Treatment of Cutaneous Non-Genital Warts (NCT04554394), a randomized na study. The primary outcome is Percentage of Verrucae Cleared.

2. Clinical Question

3. Trial Design

The study is titled as a prospective, non-randomized, multicenter pivotal study of Nano-Pulse Stimulation treatment for cutaneous non-genital warts. Its stated purpose is to evaluate safety and effectiveness of the CellFX System in patients with these warts, excluding warts on the face. The registry records the study as completed, with a start date of 2019-07-17 and primary completion date of 2020-06-09. Enrollment is recorded as 62.

The design fields do not align cleanly with the narrative description. Allocation is recorded as randomized, while the title and brief summary call the study non-randomized. The model is listed as single group, yet arm descriptions identify a CellFX-treated wart and a non-treated control wart for each enrolled subject. These entries should be read as discrepancies in how the registry record characterizes the design, not as evidence that a particular randomization procedure or between-group analysis took place.

The primary-outcome description also limits the comparison that can be interpreted. It says that clearance or size reduction was not assessed in the non-treated control arm or a similar group. Thus, despite the description of control warts, the posted primary endpoint is not reported as a treated-versus-control effect. No randomization method, allocation ratio, masking procedure beyond the masking field of none, or detailed analysis plan is reported. The registry lists subject satisfaction as a secondary outcome, but no result for that outcome appears in the 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: 62 subjects were enrolled. One wart per subject was randomized and pre-assigned as the control.

Overall Study

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: Percent of verrucae clearance observed at 60-days post-last treatment. Reduction in verrucae size and/or clearance not assessed in the "Non-treated Control" Arm/Group or similar.

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.

Population: Subjects diagnosed with cutaneous warts, including common, flat and plantar subgroups

6. Primary Endpoint

The registry lists the primary outcome as Percentage of Verrucae Cleared, measured over 60-days post-last CellFX treatment.

The primary endpoint is titled “Percentage of Verrucae Cleared,” with the unit described as percentage of verrucae clearance. It is assessed at 60-days post-last CellFX treatment. A verruca counts as cleared under the stated definition when it has a 91-100% reduction. The record describes this as the percentage of verrucae with clearance, rather than a measure of the average change in wart size.

In general, a threshold endpoint converts a continuous change, such as reduction in lesion size, into a category defined by a prespecified cutoff. This can make a result easier to interpret as the fraction meeting a clinically defined level of response, but the cutoff also discards information about variation within categories. For example, the endpoint does not distinguish among reductions that fall within the same stated clearance range. This is a general feature of threshold outcomes, not a claim about the study’s observed data.

The registry record does not report the observed endpoint value, the number of verrucae assessed, or an uncertainty interval. It also says that clearance and size reduction were not assessed in the non-treated control arm or a similar group. Accordingly, this endpoint can be described as a post-treatment clearance measure, but the record does not support interpreting it as a comparative treatment effect.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

Statistical interpretation begins with identifying what quantity the endpoint is intended to estimate. Here, the stated primary quantity is the percentage of verrucae with clearance at 60-days post-last CellFX treatment, using a 91-100% reduction threshold. This is a proportion-type endpoint: each assessed verruca would be classified according to whether it meets the threshold, and the percentage would describe the share meeting it. The registry record does not report the numerator or denominator needed to reproduce or evaluate that proportion.

What would an uncertainty interval describe?

In general, a confidence interval expresses uncertainty around an estimate under a statistical model and its assumptions. For a proportion, it can indicate how much the estimated proportion might vary because only a sample of eligible outcomes was observed. Its width depends on factors such as the amount of information and the observed outcome pattern. The registry record reports no confidence interval for the primary endpoint, so neither precision nor a plausible range for the underlying clearance proportion can be assessed from this record.

A confidence interval is not a guarantee that the true value lies within its limits, nor does it replace consideration of the study design. In particular, an interval for a treated group alone would not establish a contrast with untreated warts. The control-wart description does not resolve this issue because the primary-outcome text says control clearance was not assessed. No comparative estimate or interval is reported.

Why does the analysis unit matter?

The endpoint refers to verrucae, while enrollment refers to the study population. These are not necessarily interchangeable units of analysis: a participant may contribute more than one wart. If multiple lesions from the same participant were included, their outcomes could be correlated. In general, analyses that account for within-participant clustering can produce uncertainty estimates that better reflect this dependence. An analysis that assumes every lesion is independent may understate uncertainty when outcomes within a participant are related. The registry record does not report the number of lesions assessed, the analysis unit, or any method for handling clustering, so it is not possible to determine which approach was used.

The arm descriptions call the non-treated wart a control wart for each enrolled subject. Such wording may suggest a within-subject structure, but it does not establish that paired outcome data were collected or analyzed. A paired analysis requires outcome information for both members of a pair and a method that uses that pairing. The primary-outcome description says the non-treated control arm or similar group was not assessed for clearance or size reduction. No paired analysis can therefore be inferred from the arm wording alone.

What does the registry say about the analysis plan?

The registry records zero analyses and does not report a statistical analysis plan for the primary outcome. It does not specify an estimator, model, hypothesis test, handling of missing observations, or method for accounting for the apparent design discrepancies. The allocation field says randomized, while the study description says non-randomized and the model says single group. Those classifications have different implications for how a comparison might be interpreted, but the record does not supply enough detail to determine which design procedures were implemented.

In general, randomization can support causal comparisons when allocation is implemented as planned and outcomes are analyzed appropriately. A non-randomized study may be more susceptible to differences between groups or lesions that are not due to treatment. Neither general principle resolves the contradictory registry entries or establishes that the study’s primary endpoint was comparative. The record’s explicit statement that control clearance was not assessed is the key limitation for interpreting the primary outcome as an effect relative to control.

How should planning calculations be understood?

Sample-size planning asks how much information a future study might need to detect a specified effect under stated assumptions. The registry’s planning description refers to a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation, with the effect defined as a fraction of the observed effect. It also distinguishes planning for time-to-event outcomes from planning for other outcomes. These are planning assumptions, not evidence that the actual study used that design or analysis.

The registry record does not report the observed primary effect needed to support those calculations, nor does it report resulting planning estimates in the registry record for this analysis. Any such illustration should be treated as conditional on its assumptions, not as a description of the enrolled study. Sample-size calculations are not observed power. Observed power is not a substitute for reporting an estimate and its uncertainty, and a planning calculation cannot fill in the absent endpoint result.

Finally, statistical significance and clinical meaning are different questions. In general, a p-value addresses compatibility of data with a specified null model, while an estimate and its uncertainty describe magnitude and precision. Neither can be evaluated for the primary outcome because the registry record reports no outcome estimate or test. Statistical concepts can clarify what information would be useful, but they cannot supply results absent from the record.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists two outcome measures and names subject satisfaction as a secondary outcome. It does not report results for that secondary outcome, nor does it describe how satisfaction was measured. No analysis details are reported for either outcome, and the analysis count is zero. The primary endpoint is specified, but its result is absent.

Multiplicity arises generally when several outcomes, time points, subgroups, or statistical tests are considered. Repeated testing can increase the chance of a seemingly notable result arising by chance unless the analysis plan addresses that issue. The registry record does not report a multiplicity strategy, a hierarchy of outcomes, or whether any adjustment was planned. It would be inappropriate to infer either that multiplicity was controlled or that it was ignored in an analysis that is not described.

The record also does not report how missing endpoint observations were handled, whether all enrolled participants or lesions were included in the primary analysis, or how the analysis population was defined. It does not state how many verrucae were assessed or whether participants with multiple lesions contributed multiple observations. These omissions prevent evaluation of the denominator and the possibility of bias from incomplete outcome data. They also limit interpretation of any planning illustration based on observed effects, since the underlying result and analysis population are not given.

In general, transparent reporting of outcome definitions, analysis populations, missing-data handling, and multiplicity methods helps readers distinguish prespecified analyses from exploratory ones and assess the robustness of conclusions. Those details are not reported in the registry record. This absence is a reporting limitation; it does not establish that no such procedures existed outside the record.

11. Safety Results

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

Deaths

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 1% reporting threshold.

Most frequent non-serious adverse event terms

The safety entries list the CellFX Treated Wart Lesion group. For serious adverse events, 62 are listed as at risk and 0 as affected; deaths are reported as 0. For other adverse events, 62 are listed as at risk and 8 as affected. The registry does not provide serious adverse event terms, and the listed top serious terms are empty.

These are registry counts, not a complete description of event severity, timing, duration, or relationship to treatment. The record does not explain the distinction between the serious and other-event categories or provide individual event descriptions. It also does not explain the at-risk denominator beyond the entries themselves. The two at-risk entries should therefore be reported as recorded, rather than combined or interpreted as distinct participant totals.

In general, a count of zero reported events does not establish that an intervention has no risk; it indicates that no events in that category are recorded among the stated at-risk group in this registry entry. Conversely, the count of other events does not by itself establish their seriousness or cause. The safety figures should be read alongside the limited reporting detail and should not be used to infer information the registry does not report.

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

The record establishes that a completed, prospective, multicenter study of the CellFX System for cutaneous non-genital warts was registered, with enrollment recorded as 62. It specifies a primary endpoint based on the percentage of verrucae meeting a 91-100% reduction threshold at 60-days post-last treatment. It also reports a small set of safety counts. These details describe the intended question and selected registry entries, but they do not provide the primary efficacy result.

The registry record does not report the percentage of verrucae cleared, the number assessed, or an uncertainty interval. It says that reduction in size and/or clearance was not assessed in the non-treated control arm or a similar group. Consequently, the record does not support a numerical estimate of the treatment effect relative to untreated warts. The description of a control wart for each subject is not enough to establish that comparative outcome data were collected or analyzed.

The record’s study classifications are internally inconsistent: the title describes a non-randomized study, the allocation field says randomized, and the model is listed as single group. Those entries do not establish which allocation process was followed. The analysis plan and methods for handling multiple lesions, missing observations, and the analysis population are not reported. These gaps constrain conclusions about both the validity and precision of any study estimate.

The safety entries report 0 serious adverse events and 0 deaths, alongside 8 other adverse events among 62 listed as at risk for other events. Those counts should be interpreted narrowly because event descriptions and additional context are not reported. Overall, the registry record documents study design intent and limited safety information, but it does not allow a reader to judge the magnitude, precision, or comparative nature of the primary outcome.

13. Why This Trial Matters Statistically

This trial is statistically notable because its registry record illustrates why a clearly named outcome is not enough to evaluate a study result. The endpoint is defined with a specific clearance threshold and assessment time, yet the record does not report the observed percentage, its denominator, or its uncertainty. Without those elements, readers cannot assess either the magnitude of the result or how precisely it was estimated.

The mismatch between design fields is also important. A non-randomized description, a randomized allocation entry, a single-group model, and arm descriptions naming treated and non-treated warts appear together in the record. Design determines which comparisons are meaningful and what assumptions support them. The entries do not establish a specific allocation method or comparative analysis, so the primary result cannot be interpreted as a controlled treatment effect from this record.

The endpoint is stated at the verruca level, while enrollment is stated for the study population. In general, when several lesions come from one participant, their outcomes may be related. Reporting the analysis unit and any method for accounting for this relationship is important for interpreting uncertainty. Those details are not reported. The record also says control clearance was not assessed, making the described control-wart structure insufficient for a primary-outcome contrast.

These issues matter beyond this study: registry transparency allows readers to distinguish planned outcomes from reported findings and to see whether the design supports the claims being considered. In this case, the outcome definition and safety counts are available, but the primary result and key analysis details are not reported in 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.

Several limitations specific to this record constrain interpretation. The study is described as non-randomized in its title and summary, while the allocation field records randomized and the model is listed as single group. Arm descriptions nevertheless distinguish CellFX-treated and non-treated warts. The registry does not explain these conflicting entries or report the actual allocation procedures, so the design cannot be reconstructed confidently from the record.

The primary endpoint is described as clearance among verrucae at 60-days post-last treatment, with clearance defined as a 91-100% reduction. The record states that reduction and/or clearance was not assessed in the non-treated control arm or a similar group. This limits interpretation to a treatment-group endpoint as described; it does not support a direct comparative estimate. The observed endpoint value and its denominator are also not reported.

The record does not give the number of lesions assessed, the unit used in the analysis, or a method for handling possible dependence among multiple warts from the same participant. It does not report the analysis population, missing-data handling, or a statistical plan. Although subject satisfaction is listed as a secondary outcome, its measurement and result are not reported. The record gives no primary-outcome confidence interval or test result, and no analyses are listed.

Safety reporting is limited to event counts and at-risk entries. Serious adverse event terms are not listed, and the record does not describe the other adverse events. These are limitations of the available registry record; they do not establish what may have been reported elsewhere.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: CellFX System for the Treatment of Cutaneous Non-Genital Warts — NCT04554394.
• Registry record last updated 2023-07-27; status last verified 2023-06.
• Results first posted 2023-07-27.
• 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.

18. Record Summary

NCT04554394 concerns the CellFX System for cutaneous non-genital warts. The registry describes a prospective, multicenter pivotal study and records it as completed. Enrollment is 62, with a start date of 2019-07-17 and primary completion date of 2020-06-09. The study description excludes facial warts.

The primary endpoint is the percentage of verrucae cleared, defined as a 91-100% reduction and assessed at 60-days post-last treatment. The record does not report the endpoint result or a statistical analysis. It describes treated and non-treated warts, but states that control clearance or size reduction was not assessed. Design entries conflict on randomization and study model.

The safety record lists 0 serious adverse events, 0 deaths, and 8 other adverse events, with 62 at risk in each listed category. Subject satisfaction is named as a secondary outcome without a reported result. The registry record therefore supplies the outcome definition and limited safety counts, but not the primary result or the analysis detail needed to assess its magnitude and precision.