Evaluation Of Acceptability And Satisfaction Of Hemophilia Patients Treated With FusENGO: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Evaluation Of Acceptability And Satisfaction Of Hemophilia Patients Treated With FusENGO (NCT01959919), a registered phase not stated study. The primary outcome is Ease of Using Clotting Factor Treatment Score.

2. Clinical Question

The study was designed to prospectively investigate patients’ experiences and satisfaction with Factor VIII treatment delivered using FuseNGO. Its stated focus was acceptability and satisfaction, rather than a randomized test of clinical efficacy. The registry describes treatment on demand and prophylaxis, but does not report how participants were distributed between these treatment approaches or whether results were analyzed separately for them.

The central statistical question is therefore descriptive: what did participants report about ease of treatment, and how variable were their scores? A comparison with previous delivery systems would need information about how that comparison was collected and analyzed. Those details, along with a numerical primary endpoint result, are not reported in the registry record. The study’s design and available safety counts cannot establish a causal difference between delivery systems.

3. Trial Design

The registry identifies this as a non-interventional longitudinal study. It describes prospective assessment of experiences during treatment with Factor VIII in the FuseNGO delivery system, compared with participants’ previous delivery system. The stated observation period was 3- 6 months and not to exceed 12 months, according to local therapeutic plans. The primary endpoint is specified at the Final Visit (Month 8); the registry does not explain how this endpoint timing relates to the variable observation period described in the study summary.

The registry lists Refacto FusENGO as a device intervention and identifies a single device arm. It does not describe random allocation, a concurrent control arm, or a protocol-driven treatment assignment. The record explicitly notes that this is not a randomized comparison and that the arms are not a like-for-like control comparison. As a result, the study is not structured to isolate the effect of the delivery system from other differences between people or their treatment circumstances.

Enrollment is listed as 86. That is the registry’s enrollment figure; it should not be treated as the number contributing to the primary endpoint, because the stated per-protocol population required both at least 1 treatment using Refacto AF FuseNGo and completion of the two final questionnaires. The number meeting that endpoint population definition is not reported in the registry record.

The study is marked completed. Its start date is 2014-01-27 and its primary completion date is 2016-12-12. The sponsor is Pfizer. The registry lists 7 outcome measures and 5 analyses, but does not provide enough detail in the available record to reconstruct the full analysis plan, timing of every measurement, or handling of all outcome data.

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

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: Per-protocol population included all participants who received at least 1 treatment using the Refacto AF FuseNGo and completed the two final questionnaires.

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: Safety population included all the participants who were enrolled and received at least 1 dose of Refacto AF FuseNGo.

6. Primary Endpoint

The registry lists the primary outcome as Ease of Using Clotting Factor Treatment Score, measured over Final Visit (Month 8).

The primary endpoint is the Ease of Using Clotting Factor Treatment Score, measured in units on a scale at the Final Visit (Month 8). It uses four participant-rated HaemoPREF items: ease of preparing treatment for injection, ease of storing treatment, ease of disposing of containers, syringe and needle after use, and ease of using the current treatment. Each item is scored from 0 (not at all easy) to 10 (extremely easy), and the four item scores are summed to produce an overall score from 0 (no ease) to 40 (maximum ease). Higher scores indicate greater ease in using clotting factor treatment.

This endpoint is relevant to the study’s stated aim because it captures participants’ reported experience of practical aspects of treatment delivery. It is a patient-reported measure, not a laboratory measure or a direct measure of bleeding control. A mean score can describe the average reported ease in the analyzed population; the standard deviation describes how spread out individual scores are around that mean. Neither statistic, by itself, establishes why participants gave their ratings.

The registry identifies the endpoint parameter as a mean with standard deviation, but its numerical mean and standard deviation are not reported in the registry record. The number of participants contributing to this endpoint is also not reported in the registry record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry identifies the primary outcome as a continuous measure and specifies a mean with standard deviation. A continuous outcome can take values across a scale, rather than being limited to categories such as yes or no. For this endpoint, the possible overall score extends from 0 to 40. A mean describes the average score among participants included in the analysis. A standard deviation describes the spread of participant scores around that average; it is not the same as the uncertainty in the estimated mean.

What does the score represent?

The total is formed by summing ratings on four ease-related items. Because each item concerns a practical aspect of using treatment, the total combines several related experiences into one measure. This summary is useful for describing overall reported ease, but it does not show which individual item most influenced a participant’s total. Item-level results are not reported in the registry record.

Higher scores have a stated interpretation of greater ease. The scale’s endpoints provide context for understanding a reported total, but the registry does not report a numerical group mean or standard deviation. No confidence interval or other measure of precision for the primary result is reported in the registry record. In general, a confidence interval expresses uncertainty around an estimate; it does not describe the spread of individual participant scores. Without the reported estimate and its precision, the magnitude and uncertainty of the average score cannot be assessed.

What can a one-arm design estimate?

The registry lists a single device arm and describes a non-interventional longitudinal study. A descriptive analysis can characterize reported scores among participants who meet the stated population definition. It cannot, on its own, distinguish an effect of the device from other influences. Although the study description refers to participants’ previous delivery system, details of a formal paired comparison, the relevant analysis population, and the statistical method for such a comparison are not reported in the registry record.

In general, a randomized concurrent comparison helps separate treatment differences from systematic differences between groups. This record does not describe such a randomized comparison. The analysis should therefore be read as descriptive unless additional methods and results are reported elsewhere in the registry record. The study’s non-interventional character is important when interpreting any apparent change in reported experience over time.

How should the planning illustrations be understood?

The stated planning illustration assumptions are a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. The effect to detect is defined as a stated fraction of the observed effect. These are planning assumptions, not evidence about the study’s original design. The registry does not report the study’s own sample-size justification, so the planning illustration should not be presented as the trial’s planned enrollment rationale.

Any sample-size values derived from these assumptions are planning illustrations, not observed power. Observed power is not a substitute for reporting the estimated effect and its uncertainty. In general, sample-size planning asks how much information a proposed study might need under specified assumptions. It does not reveal whether an observed result is precise, clinically important, or free from bias. The illustration’s assumption of equal allocation between two arms should also not be mistaken for the design recorded for this study, which lists one device arm.

The illustration uses a fraction of the observed effect as its target. Such a calculation depends on the observed effect used as its starting point and on its assumptions. The actual numerical planning results are not stated in the registry record. They should not be used to imply that the study had a particular power or that its analysis confirmed an effect.

What statistical details remain unavailable?

The registry record does not report the primary endpoint’s mean, standard deviation, confidence interval, or analyzed participant count. It also does not report whether any adjustment was made for multiple outcomes or analyses, how missing questionnaire items or incomplete questionnaires were handled, or whether any sensitivity analyses were conducted. The record lists 7 outcome measures and 5 analyses, but those totals do not establish which outcomes were prespecified as primary or how statistical testing was organized beyond the named primary endpoint.

For a continuous score, an analysis may need to consider whether the distribution is suitable for the chosen summary and method. The statistical plan and underlying score distribution are not reported, so no judgment about model assumptions or distributional fit is possible. These limitations do not invalidate the stated measure; they constrain how much can be concluded from the registry information.

10. Confidence Intervals for Each Arm

No two-arm comparison is shown for this trial, but each arm's mean can be given with a t-based 95% confidence interval computed from the posted mean, spread and number of participants.

R code and output

arm <- c("Refacto AF FuseNGo")
n   <- c(84)
m   <- c(31.15)
sp  <- c(6.539)
sd  <- sp      # posted standard deviations
for (i in seq_along(n)) {
  se <- sd[i] / sqrt(n[i]); h <- qt(0.975, n[i] - 1) * se
  cat(sprintf("CARM|%s|%d|%.3f|%.3f|%.3f|%.3f\n", arm[i], n[i], m[i], sd[i], m[i] - h, m[i] + h))
}

CARM  Refacto AF FuseNGo  84  31.150  6.539  29.731  32.569

11. Multiplicity, Missing Data and Analysis Populations

The registry identifies one primary endpoint: the mean Ease of Using Clotting Factor Treatment Score at the Final Visit (Month 8). It also lists 7 outcome measures and 5 analyses. The record does not describe how the primary endpoint was distinguished from other analyses in the statistical plan, whether multiple testing was addressed, or whether any adjustment to significance thresholds was planned. The method for controlling false-positive findings across multiple outcomes or analyses is not reported in the registry record.

The endpoint analysis population is defined per protocol. Participants had to receive at least 1 treatment using Refacto AF FuseNGo and complete the two final questionnaires. The number who met these criteria is not reported in the registry record. The record also does not explain how participants who did not complete questionnaires were handled, whether partial questionnaires could contribute to a score, or how missing item responses were treated. There is no reported imputation method or sensitivity analysis for missing data.

The enrollment figure of 86 should not be assumed to be the endpoint analysis size. Enrollment and endpoint availability are not interchangeable, especially when questionnaire completion is part of the analysis population definition. The registry does not provide a participant flow or counts for exclusions from the per-protocol population.

The record does not report whether additional analysis populations were used or whether analyses were adjusted for participant characteristics. Nor does it provide the statistical analysis plan needed to establish whether analysis choices were set before results were known. These absences limit assessment of potential selection, missing-data, and multiplicity concerns. They are not evidence that a particular method was or was not used; the relevant details are not reported in the registry 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 0% reporting threshold.

Most frequent non-serious adverse event terms

The registry records 0 participants with serious adverse events among 86 at risk in the Refacto AF FuseNGo group. It records 3 participants with other adverse events among 86 at risk. These are participant counts as entered in the record; they are not a comparison between treatment groups, because only one device group is listed.

The record does not list serious adverse event terms. It also does not report whether recorded events were judged related to treatment or the device, when they occurred, how severe they were, or whether they led to changes in treatment. The death count is not reported in the registry record; a missing value should not be read as a count of zero.

These safety figures are descriptive and should be interpreted within the study’s non-interventional design. They do not establish that the device caused or prevented an event, and they do not provide a comparative estimate against another delivery system. The registry lists adverse events and serious adverse events as a secondary outcome, but the available counts alone do not supply details about event types or follow-up completeness.

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

The registry record describes a study of treatment experience with a Factor VIII delivery system in people with Hemophilia A. Its primary measure focuses on reported ease of using treatment, combining ratings of preparation, storage, disposal, and use. The score has a defined range and direction, making its intended interpretation clear: higher totals indicate greater ease.

That definition does not substitute for the observed result. The primary mean and standard deviation are not reported in the registry record, so the average experience and variation among participants cannot be characterized from the available information. The record also does not report the number contributing to the primary analysis. Consequently, the endpoint’s precision and the extent of missing questionnaire data cannot be evaluated.

The design is non-interventional and lists one device arm. Although participants’ previous delivery system is mentioned in the study description, the registry does not establish a randomized or concurrent comparison. The record therefore does not support attributing any difference in experience to the delivery system itself. It also does not establish an effect on clinical outcomes such as bleeding, because the primary endpoint is a treatment-experience score and the available the registry entries do not report a clinical efficacy result.

The safety record includes 0 participants with serious adverse events and 3 with other adverse events among 86 at risk in the listed group. These counts do not provide comparative evidence, details of event type, or a basis for determining causality. The death count is not reported in the registry record.

In short, the registry establishes what the study intended to measure and the design context in which it was measured. It does not report enough outcome data to quantify the primary result or its uncertainty. The findings should not be described as proof that treatment is easier or harder, or that the device changes safety outcomes.

14. Why This Trial Matters Statistically

This study addresses a type of question that can be missed when research focuses only on clinical outcomes: how people experience the practical work of using a treatment. Preparation, storage, disposal, and use are distinct aspects of treatment delivery, and the primary score brings participant ratings of these aspects together. For biostatisticians and clinical researchers, this illustrates the value of defining patient-reported measures with a clear scale, item content, and direction of interpretation.

The registry also illustrates why a well-defined endpoint is only one part of an interpretable result. The primary measure is described in detail, including its item content and score range, but its observed mean, standard deviation, and analysis size are not reported in the registry record. Without these, readers cannot judge the average experience, variability, or precision. Transparent reporting of estimates, uncertainty, and analyzed populations is essential to make a patient-reported result useful.

The non-interventional, single-arm design matters as well. Experience with a new delivery system may be relevant to care, but a descriptive study does not by itself establish that the system caused a reported difference from a previous one. The registry’s reference to a prior delivery system does not provide the methods or results needed to evaluate such a contrast.

Finally, the safety counts demonstrate why event totals need context. Counts without event descriptions, attribution, follow-up details, or a comparison group give a limited account of safety. The study is statistically instructive because it combines a meaningful experience measure with substantial limits on what the available record can establish.

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 main limitation for interpretation is that the registry record does not report the numerical primary endpoint result. Although it defines the score and identifies a mean and standard deviation as the summary, readers cannot assess the reported level of ease, score variability, or statistical precision. The number of participants with analyzable endpoint data is also not reported.

The primary population is restricted to participants who received at least 1 treatment using Refacto AF FuseNGo and completed the two final questionnaires. The record does not report how many participants met this definition, how incomplete questionnaires were handled, or whether exclusions from the per-protocol population could have affected the results. This makes it difficult to assess how representative the analyzed participants were of those enrolled.

The study is described as non-interventional and lists one device arm. Although the study summary refers to participants’ previous delivery system, the registry does not report a concurrent control group, a formal comparison method, or results for such a comparison. A causal interpretation of differences in treatment experience is therefore not supported by the available record.

The registry also does not report the full statistical analysis plan, methods for handling missing data, multiplicity procedures, or sensitivity analyses. It describes a variable observation period according to local therapeutic plans, while identifying the primary endpoint at the Final Visit (Month 8); the relationship between those timing descriptions is not explained. The registry lists adverse-event counts but does not provide event terms or attribution details. These are limitations of the information reported in the registry, not proof that unreported procedures or analyses were absent.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Evaluation Of Acceptability And Satisfaction Of Hemophilia Patients Treated With FusENGO — NCT01959919.
• Registry record last updated 2018-09-25; status last verified 2018-09.
• Results first posted 2018-09-25.
• 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

The registry record describes a completed, non-interventional longitudinal study of Refacto FusENGO, a Factor VIII delivery system, in people with Hemophilia A. Enrollment is listed as 86; the study start date is 2014-01-27 and the primary completion date is 2016-12-12. The study aimed to investigate treatment experience over a period described as 3- 6 months and not to exceed 12 months according to local therapeutic plans.

The primary endpoint is the mean Ease of Using Clotting Factor Treatment Score at the Final Visit (Month 8). It combines four HaemoPREF item ratings into a score from 0 to 40, with higher scores indicating greater ease. The endpoint result and analyzed population size are not reported in the registry record. The registry identifies a per-protocol population requiring at least 1 treatment with Refacto AF FuseNGo and completion of the two final questionnaires.

For safety, 0 serious adverse events and 3 other adverse events are recorded among 86 at risk in the device group. Event terms and the death count are not reported in the registry record. The study lists one device arm and is not a randomized comparison.