Testopel ® vs. Generic Testosterone Pellets.: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Testopel ® vs. Generic Testosterone Pellets. (NCT04523480), a randomized phase 3 study. The primary outcome is Change in Testosterone (T) Levels.

2. Clinical Question

3. Trial Design

The registry identifies this as a phase 3 randomized, parallel-group trial with no masking. Its title describes a comparison of Testopel and generic testosterone pellets. The brief summary states that the study was intended to evaluate changes in vascular parameters among participants with clinical hypogonadism receiving one-time pellet insertions. The registered primary outcome, however, is change in testosterone levels. Vascular outcomes are not identified as the primary endpoint in the record.

The treatment descriptions specify one-time subcutaneous insertions. The Testopel 75mg Group is described as receiving 10 pellets, totaling 750 mg. The Compounded testosterone pellets 100mg Group is described as receiving 8 compounded pellets, totaling 800 mg. A Compounded Testosterone pellets 200mg Group is also described, with 4 compounded pellets totaling 800 mg, but the record says no participants entered that group because the pharmacy could not produce the product at that dosage. The intervention list uses the names Testopel 75mg, Testopel 100mg, and Testopel 200mg, while the arm descriptions identify the 100mg and 200mg products as compounded testosterone. This difference in naming is part of the registry record.

The registry reports enrollment of 75, a start date of 2020-03-12, primary completion on 2022-12-20, and a completed status. It does not report the allocation sequence, the method used to conceal assignments, or further operational details about recruitment and follow-up. Randomization is recorded, but the absence of masking means that participants and study personnel were not described as masked. The record does not establish which outcome assessors, if any, were masked.

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: Zero participants were enrolled into the "Compounded Testosterone pellets 200mg Group" due to the pharmacy being unable to produce the investigational product at that dosage amount.

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: No subjects were enrolled to the 200mg group due to complications with the compounding pharmacies ability to produce the medication.

6. Primary Endpoint

The registry lists the primary outcome as Change in Testosterone (T) Levels, measured over Baseline, 2 months, 4 months, and 6 months.

The primary endpoint is change in serum testosterone levels, measured in ng/dL. The record specifies measurements at baseline, 2 months, 4 months, and 6 months and says that results are expressed as medians with inter-quartile ranges. It does not report the values at those time points, the calculated changes, or a comparison between groups.

In general, a blood concentration can serve as a biochemical measure of how a treatment is associated with a hormone level over time. Describing change from baseline gives a within-participant reference point, while comparing changes between randomized groups can address whether the observed patterns differ by assigned treatment. These are general interpretations of the endpoint type; they do not establish what happened in this trial.

The registry lists change in hematocrit, PSA, and estradiol as secondary outcomes. It reports four outcome measures overall, but does not provide results for those secondary outcomes in the record. The primary outcome is therefore identifiable by its name, unit, summary measure, and time points, but its numerical findings and inferential uncertainty are not reported in the registry record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The statistical features identifiable in the registry record are the randomized parallel design, the outcome’s median and inter-quartile-range summary, its repeated time points, and the absence of reported analyses. The explanations below describe general statistical concepts and do not imply that a particular unreported method was used in this trial.

What does randomization contribute?

In general, random assignment is intended to make treatment groups comparable at the point of assignment, including with respect to factors that were not measured. If assignment is implemented as planned and the analysis preserves the randomized comparison, differences in outcomes can be interpreted more credibly as associated with assignment than differences in nonrandomized groups. Randomization does not guarantee that groups will be identical, and it does not address problems such as missing follow-up or incomplete outcome reporting. The registry records randomized allocation but does not describe the sequence-generation or assignment-concealment methods.

In this trial, the planned comparison included the compounded 200mg group, but no participants entered it. Random assignment cannot support a comparison with an empty group: there are no observations from that group from which to estimate its outcome distribution. The record also does not report how assignment was handled after that product could not be produced, so the operational consequences for allocation are not reported in the registry record.

Why report a median and inter-quartile range?

In general, the median is the middle value after observations are ordered. The inter-quartile range describes the span from the lower to the upper quartile and gives information about the spread of the central portion of the observations. These summaries can be useful when data are skewed or include values that would strongly influence a mean. They do not describe every feature of a distribution, and a median with an inter-quartile range does not by itself quantify uncertainty about a treatment-group difference.

The registry names these summaries for testosterone levels, but does not provide the actual medians or inter-quartile ranges. It also does not state whether the summary applies to raw levels at each visit, changes from baseline, or both. The endpoint title specifies change, while the description says serum testosterone levels are assessed. Additional details about the exact calculation of change are not reported in the registry record.

How should repeated measurements be understood?

In general, measurements on the same participant over time are correlated: a participant’s values tend to be related to their own earlier values. Analyses that compare repeated measurements can account for this within-participant structure, but the appropriate model depends on the scientific question and the data. A model might focus on change at a particular follow-up, an overall time pattern, or differences between groups across time. The registry lists baseline, 2 months, 4 months, and 6 months but does not identify a repeated-measures model, a primary follow-up contrast, or a method for handling the correlation between visits.

The record also does not state how measurements were handled if a participant missed one or more visits. Methods for incomplete repeated data can rely on different assumptions, and conclusions may depend on whether those assumptions are reasonable. Without the analysis plan and participant-level outcome information, it is not possible to evaluate those choices.

What do confidence intervals and p-values usually add?

In general, a confidence interval describes the precision of an estimated effect under the assumptions of the statistical method. A narrow interval indicates greater precision than a wide interval, while the range of values in the interval helps readers judge which effect sizes remain compatible with the data. A p-value measures how unusual data at least as incompatible with a specified null hypothesis would be under a statistical model. Neither measure gives the probability that a treatment works, and neither substitutes for understanding the estimate itself.

No confidence interval or p-value for the primary outcome is reported in the registry record. The record lists zero analyses, so there is no reported model result to interpret. The absence of an inferential result is not evidence of no difference; it leaves the comparison unresolved in this record.

What do planning calculations mean?

In general, sample-size planning asks how many participants may be needed to detect a chosen effect under specified assumptions. A planning illustration is not an observed outcome and is not the probability that a completed trial detected an effect. The registry description of planning assumptions refers to a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation, with the target effect expressed as a fraction of an observed effect. Those assumptions do not establish the trial’s own design rationale. A sample-size justification or protocol-based calculation is not reported in the registry record, and no numerical planning estimate is reported in the information.

10. Multiplicity, Missing Data and Analysis Populations

The primary outcome is described across baseline, 2 months, 4 months, and 6 months, and the record also lists secondary changes in hematocrit, PSA, and estradiol. When several outcomes, time points, or group contrasts are examined, the chance of finding an apparently notable result by chance can increase. In general, multiplicity procedures can define a priority order, adjust inference, or otherwise clarify how findings should be interpreted. The registry record does not report a multiplicity strategy, a hierarchy among the time points, or which contrast was considered primary for statistical testing.

The record lists four outcome measures and zero analyses. It does not provide results for the primary outcome or the named secondary outcomes. It also does not report an analysis plan explaining whether each outcome was measured at every visit, how the change score was constructed, or whether any outcome was analyzed with an adjusted model. Those details are not reported in the registry record; no specific method should be inferred from the endpoint descriptions alone.

Participant flow and analysis populations are also not described. The record gives enrollment of 75 and safety counts at risk for the 75mg Testopel and 100mg compounded groups, but it does not identify an intention-to-treat, per-protocol, or other efficacy population. It does not state how many participants completed each visit, whether any data were excluded, or how missing measurements were handled. The absence of these details limits assessment of both missing-data bias and the connection between randomized assignment and the reported safety denominators.

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 0% reporting threshold.

Most frequent non-serious adverse event terms

The adverse-event listing reports zero serious adverse events among 33 participants at risk in the Testopel 75mg Group and zero among 42 participants at risk in the Compounded Testosterone Pellets 100mg Group. It also reports zero deaths in each of those groups. For other adverse events, the registry lists one affected participant in the Testopel 75mg Group and zero in the 100mg compounded-pellet group. The 200mg compounded-pellet group has zero participants at risk and no reported events.

These are registry counts, not estimates of comparative risk. The record does not provide event descriptions, timing, severity details for the other adverse event, or an assessment of relatedness. It also does not explain how events were collected or whether the listed denominators apply throughout the entire follow-up period. Zero serious events in the listed groups does not establish that serious events cannot occur or that treatments have equivalent safety. The lack of participants in the 200mg group means its event listing cannot inform safety among exposed participants.

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

The record establishes that a randomized, unmasked, parallel-group phase 3 trial was registered as completed, with a primary outcome of testosterone-level change over the stated follow-up visits. It also establishes that the planned compounded 200mg group enrolled no participants because the pharmacy could not produce that dosage. The record contains safety counts for the groups with participants at risk and describes the planned insertion regimens.

It does not establish the size or direction of testosterone changes, whether changes differed between groups, or how precise any estimated difference was. No primary outcome values, confidence intervals, p-values, or analyses are reported. The registered endpoint therefore cannot be interpreted as a demonstrated treatment effect or as evidence that the groups had the same outcomes. The lack of a reported analysis leaves the primary comparative question unanswered in this registry record.

In general, randomization is a strength for comparing assigned interventions, but its benefits depend on having outcome information and a suitable analysis. It does not compensate for an unrepresented treatment group, missing outcome reporting, or uncertainty about analysis populations. Here, the absent 200mg group prevents an outcome comparison involving that regimen, while the lack of reported outcome estimates also prevents interpretation of the other planned comparison.

The safety counts are similarly limited. They describe the registry’s event listings and denominators, but do not show comparative rates, event context, or an assessment of treatment attribution. The record cannot support broad conclusions about safety or efficacy. Its useful contribution is to clarify the trial’s registered question, planned treatments, outcome schedule, and a feasibility problem that prevented enrollment in one group, while making clear that outcome analyses are not reported.

13. Why This Trial Matters Statistically

This trial is statistically informative as an example of the difference between a registered design and an interpretable result. The record specifies randomization, a parallel structure, treatment regimens, a primary endpoint, and follow-up time points. Those details define an intended comparison. They do not, by themselves, provide estimates of the outcomes or the uncertainty around those estimates.

The inability to produce the 200mg compounded product had a direct consequence for the planned group comparison: no participants entered that group. This illustrates why implementation feasibility affects the statistical question a study can ultimately address. A planned arm without observations cannot contribute an estimate, regardless of the trial’s randomized designation. The registry’s intervention names and arm descriptions also vary in how they label the products, making careful reading of the treatment descriptions important.

The endpoint’s reporting format is also relevant. A median and inter-quartile range can describe the location and spread of testosterone measurements, but comparisons across repeated visits require clear specification of the change being analyzed and the method used to account for within-participant dependence. Such methods are not identified in the registry record. The absence of the actual summaries and analyses means readers cannot evaluate whether the registered endpoint was analyzed as intended.

Finally, reporting that a trial is completed is not the same as reporting its results. The registry identifies the outcomes and safety counts, but lists zero analyses. This distinction matters for evidence synthesis and for readers deciding what conclusions can reasonably be drawn: design information describes what was planned, while estimates and uncertainty are needed to interpret what was observed.

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 main trial-specific limitation in the registry record is that the Compounded Testosterone pellets 200mg Group enrolled zero participants because the pharmacy could not produce the product at that dosage. Consequently, the record cannot provide observed outcome information for that planned group. The intervention list calls the 100mg and 200mg interventions Testopel, while the arm descriptions call them compounded testosterone pellets. The record does not explain this naming difference, so product identity should be read from the arm descriptions with that discrepancy in mind.

The primary outcome is identified as change in testosterone, but no group-level values, analyses, or inferential statistics are reported. The registry also names secondary changes in hematocrit, PSA, and estradiol without reporting their results. Although the outcome schedule is stated, the record does not specify the exact change calculation or the statistical method for repeated measurements. It is therefore not possible to judge the magnitude or precision of an outcome contrast.

Participant flow, completion by visit, analysis populations, and missing-data handling are not reported in the registry record. The safety denominators do not by themselves resolve those questions for the primary outcome. The record also does not report a multiplicity approach, a detailed statistical analysis plan, or a protocol-based sample-size justification. These limitations are specific to the information available in this record and restrict interpretation; they do not establish what may or may not have been documented elsewhere.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Testopel ® vs. Generic Testosterone Pellets. — NCT04523480.
• Registry record last updated 2023-08-14; status last verified 2023-07.
• Results first posted 2023-08-14.
• 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

The registry describes a completed, randomized, unmasked, parallel-group phase 3 trial in participants with clinical hypogonadism. Enrollment is listed as 75. The primary outcome is change in serum testosterone levels in ng/dL, summarized by median and inter-quartile range at baseline, 2 months, 4 months, and 6 months. Secondary outcomes include changes in hematocrit, PSA, and estradiol.

The treatment descriptions include one-time subcutaneous insertions of Testopel 75mg and compounded testosterone pellets at 100mg and 200mg. The record states that zero participants entered the 200mg compounded group because the pharmacy could not produce the product at that dosage. Serious adverse events and deaths are listed as zero in the groups with participants at risk; one other adverse event is listed in the Testopel 75mg Group. The registry reports zero analyses, and primary and secondary outcome results are not reported in the registry record.