Phenelzine Sulfate in Treating Patients With Non-metastatic Recurrent Prostate Cancer: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Phenelzine Sulfate in Treating Patients With Non-metastatic Recurrent Prostate Cancer (NCT02217709), a na phase 2 study. The primary outcome is Number of Patients With PSA Decline of >= 50% From Baseline Following at Least 12 Weeks of Treatment With Phenelzine Sulfate.

2. Clinical Question

In plain terms, the study was set up to describe a PSA response in a group receiving phenelzine, rather than estimate a difference between treatment groups. That distinction matters: a response count in one group does not by itself establish what would have happened to similar patients without the treatment or with a different treatment. The clinical question recorded is focused on a biomarker threshold, not a direct comparison of survival or disease progression. The registry also lists time to radiographic disease progression and the percent of common toxicities observed as secondary outcomes, but their numerical results are not reported in the registry record.

3. Trial Design

This was a phase II trial sponsored by the University of Southern California. It is recorded as completed, with a start date of 2014-09-08 and a primary completion date of 2020-06-29. The listed enrollment was 26. The study model is single group, allocation is listed as not applicable, and masking is listed as none. Thus, the registry describes one treatment group without a concurrent randomized control group or masking.

The treatment group received phenelzine sulfate. The arm description says the starting dose was 15 mg daily and that it was escalated to 30 mg by mouth twice daily over 16 plus or minus 5 days. The record also mentions possible dose escalation after more than 3 cycles at 30 mg twice daily when toxicities had resolved to grade 1 or lower, but the available arm description ends before completing the dose instruction. The full dose-modification details are not reported in the registry record.

The primary outcome is a count: the number of participants with a PSA decline of at least 50% from baseline following at least 12 weeks of treatment. Its stated timeframe is baseline to up to 12 months. Secondary outcomes include the percent of common toxicities observed and time to radiographic disease progression. The record lists 4 outcome measures, but does not provide numerical findings for the primary outcome or the named secondary outcomes.

As a single-group study, the design can describe outcomes among participants treated in the study, if those outcomes are reported. It does not provide a like-for-like treatment comparison. No additional details about the statistical plan, eligibility criteria, analysis population, follow-up procedures, or sample-size justification are reported in the registry record. The listed enrollment is the planned or recorded study enrollment figure; it should not be treated as the number with an evaluable primary outcome without an analysis population or outcome denominator.

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:

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.

6. Primary Endpoint

The registry lists the primary outcome as Number of Patients With PSA Decline of >= 50% From Baseline Following at Least 12 Weeks of Treatment With Phenelzine Sulfate, measured over Baseline to up to 12 months.

The primary endpoint is the number of participants with a PSA decline of at least 50% from baseline following at least 12 weeks of phenelzine sulfate treatment. PSA is a laboratory biomarker, and this endpoint classifies participants according to whether their measured PSA meets the stated decline threshold. The registry gives a timeframe of baseline to up to 12 months.

The registry describes a decline at this threshold as a significant indicator of a positive treatment response in prostate cancer, associated with a lower risk of disease progression and improved survival. This is the rationale recorded for using the threshold; it does not mean that this trial directly measured or established those longer-term outcomes through the primary endpoint. A PSA response is a biomarker outcome, while progression and survival are distinct clinical outcomes.

As a binary endpoint, each participant would be classified as either meeting or not meeting the threshold, assuming the required measurements and follow-up were available. A count can show how many participants in the analyzed group met the criterion, but interpretation also depends on the denominator, missing measurements, and the analysis population. The registry record does not report the primary endpoint count, denominator for the endpoint analysis, or an uncertainty interval. The endpoint definition is therefore available, but the observed response estimate cannot be assessed from this record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry record identifies a single-group phase II study and a primary outcome expressed as a participant count. It does not report the statistical analysis plan, any analysis results, or a numerical primary outcome result. The explanations below are general statistical context for reading this kind of design and endpoint; they are not claims about procedures that were used in this trial.

What does a single-group design allow?

In general, a single-group study can describe what was observed among people receiving the study intervention. For a binary outcome such as meeting or not meeting a PSA threshold, an analysis may report the number meeting the threshold and the number assessed. Those quantities are needed to interpret the observed frequency. In this record, the primary outcome is defined, but its observed count and analysis denominator are not reported in the registry record.

A single-group study does not provide a randomized comparison with a concurrent control. Randomization is one way to create treatment groups that can be compared while reducing systematic differences between them. With no comparator listed, a result in the treated group would not, on its own, quantify how the outcome differs from what would have occurred under another treatment or no treatment. This is a design-level limitation, not a statement about the size or direction of any unreported result.

How should a binary endpoint be read?

In general, a binary endpoint sorts participants into categories defined by a rule. Here the rule is a PSA decline of at least 50% from baseline following at least 12 weeks of treatment. The count is meaningful only alongside a denominator and a clear account of who was included in the analysis. A participant without an available follow-up measurement may not be classifiable from the recorded information; how missing measurements were handled is not reported in the registry record.

An estimate based on a small group can be imprecise. A confidence interval, when reported, expresses the range of values reasonably compatible with the data under the statistical model used. It does not show the range of individual outcomes, and it does not eliminate limitations in study design or measurement. No confidence interval for the primary outcome is reported in the registry record, so its precision cannot be evaluated from the posted outcome information.

What is the role of an analysis plan?

In general, a statistical analysis plan specifies how outcomes are defined and analyzed, which participants are included, and how missing observations or multiple outcomes are handled. These choices can affect how an estimate should be interpreted. Details of the trial’s statistical plan, including any inferential procedures or prespecified analysis populations, are not reported in the registry record. The record lists 0 analyses, so no analysis results are listed for interpretation.

The registry names a primary outcome and secondary outcomes, but the presence of named outcomes does not reveal whether a statistical test was performed, what model was used, or whether an adjustment for multiple testing was planned. Those details are not reported in the registry record. It would be inappropriate to infer them from the phase, design, or outcome wording alone.

Why does over-dispersion matter in some analyses?

In general, over-dispersion occurs when count data vary more than a statistical model expects. If it is ignored in a setting where it is present, uncertainty may be understated. This concept is relevant to some count-data analyses, but the primary endpoint in this record is a count of participants meeting a binary criterion, and the registry does not report a fitted statistical model or a dispersion assessment. No conclusion about over-dispersion or its handling can therefore be drawn for this trial.

How should planning estimates be distinguished from observed results?

In general, sample-size calculations describe a planned design under assumptions; they are not a substitute for observed outcome data. A planning illustration may depend on an assumed effect, significance level, allocation, and model. It cannot show that a study had a particular probability of producing a significant result after the fact, and it should not be read as observed power. The trial’s own sample-size justification and planning assumptions are not reported in the registry record. The listed enrollment of 26 is not itself a result for the primary endpoint.

For this single-group record, the main statistical information needed to evaluate the primary endpoint would include the number meeting the threshold, the denominator assessed, how missing outcome measurements were handled, and an uncertainty estimate. Those outcome details are not reported in the registry record. The design and endpoint can be described, but an effect estimate or its precision cannot be reconstructed in the registry record listed.

10. Exact Estimates for Each Arm

No two-arm comparison is shown for this trial, but each arm's result can still be summarized with exact interval estimates computed from the posted counts. The Clopper-Pearson interval is exact and conservative; the Wilson interval is a common closer-to-nominal alternative; the Bayesian credible interval uses a uniform Beta(1, 1) prior. For small groups the three can differ noticeably.

R code and output

arm    <- c("Treatment (Phenelzine Sulfate)")
n      <- c(20)
events <- c(1)
for (i in seq_along(n)) {
  ci <- binom.test(events[i], n[i])$conf.int          # Clopper-Pearson exact interval
  cr <- qbeta(c(0.025, 0.975), 1 + events[i], 1 + n[i] - events[i])   # Bayesian, uniform Beta(1,1) prior
  wi <- (function(x, n) { p <- x / n; z <- qnorm(0.975); d <- 1 + z^2 / n
    c((p + z^2 / (2 * n) - z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d, (p + z^2 / (2 * n) + z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d) })(events[i], n[i])
  cat(sprintf("ARM|%s|%d|%d|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f\n", arm[i], n[i], events[i], 100 * events[i] / n[i],
              100 * ci[1], 100 * ci[2], 100 * wi[1], 100 * wi[2], 100 * cr[1], 100 * cr[2]))
}

ARM  Treatment (Phenelzine Sulfate)  20  1  5.0  0.1  24.9  0.9  23.6  1.2  23.8

11. Multiplicity, Missing Data and Analysis Populations

The registry record lists a primary outcome and secondary outcomes, including percent of common toxicities observed and time to radiographic disease progression. It also records 4 outcome measures. The specific statistical procedures for these outcomes, and whether any adjustment for multiple testing was planned, are not reported in the registry record. Without those details, it is not possible to determine how the trial treated the possibility of chance findings across multiple outcomes or analyses.

In general, multiplicity arises when several outcomes or statistical tests are considered. Looking across multiple results can increase the chance that at least one appears notable by chance. Prespecifying a primary outcome and analysis can help clarify which result is central, while an adjustment may be used in some settings to address multiple testing. These are general considerations, not descriptions of procedures used in this trial. The registry naming a primary outcome does not establish which tests were performed or how they were interpreted.

The registry record does not report the analysis population for the primary endpoint or how missing PSA measurements were handled. Missing data can affect both the denominator and the interpretation of a response count. In general, excluding participants without follow-up measurements, classifying them in a particular way, or using a statistical method to address missingness can lead to different estimates. No such approach should be assumed.

The record lists 26 participants enrolled, but that figure does not establish how many were included in each outcome analysis. The number analyzed for the primary endpoint and the handling of withdrawals or incomplete follow-up are not reported in the registry record. No analysis results are listed. Consequently, neither multiplicity procedures nor missing-data assumptions can be evaluated from the posted record.

12. 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 serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: syncope (7.7%), hypertension (7.7%), constipation (3.8%), diarrhea (3.8%), weight gain (3.8%).

The safety record lists 26 participants at risk for serious adverse events and 8 affected. It also lists 26 at risk for other adverse events and 26 affected. These are counts for the single treatment group; there is no comparator group in the study design listed in the registry. The figures describe reported events among participants in this group and do not provide a comparative estimate of risk.

The serious adverse event terms with the largest listed percentages are syncope and hypertension, each at 7.7%. Constipation, diarrhea, weight gain, and hypotension are each listed at 3.8%. These percentages are reported as written in the registry record. The list does not give full event-level detail, such as timing, duration, recurrence, or severity for each occurrence. It also does not establish whether an event was caused by phenelzine.

One death is recorded in the treatment group. The registry record does not report its cause or relationship to treatment in the registry record. A death recorded during a study should not automatically be interpreted as treatment-related. Safety counts are useful for describing what was reported, but causal interpretation requires information beyond these group totals and terms.

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

The record establishes that this was a phase II, single-group study of phenelzine sulfate in patients with recurrent, non-metastatic prostate cancer, with enrollment of 26. It also defines a primary biomarker outcome: the number of participants with a PSA decline of at least 50% from baseline following at least 12 weeks of treatment. These registry entries describe the design and the question the trial set out to address.

The numerical primary outcome is not reported in the registry record. Consequently, the record does not establish how many participants reached the PSA threshold, how that count relates to the analyzed population, or how precise an estimate would be. The registry’s explanation that the threshold is associated with lower risk of progression and improved survival is rationale for the measure, not a trial result showing those outcomes.

Even if a response count were available, a single-group result would not demonstrate what would have happened to comparable participants under another treatment or without phenelzine. The absence of a listed control group limits causal interpretation. A biomarker response is also distinct from radiographic progression, survival, or other clinical outcomes. The registry lists some of these as secondary outcomes but does not report their numerical findings.

The safety figures describe reported serious and other adverse events in the treatment group. They do not, on their own, establish that the intervention caused an event, and they cannot show how event frequencies compare with another treatment. The recorded death likewise has no reported cause or treatment relationship in the registry entries.

Accordingly, the record is informative about the study’s structure, target outcome, and selected safety counts, but it does not support an estimate of primary PSA response or a treatment-effect comparison. Missing outcome results should not be filled in by inference from the trial title, its completion status, the endpoint rationale, or the safety counts.

14. Why This Trial Matters Statistically

This trial illustrates why a clearly stated endpoint and a reported result are both needed for statistical interpretation. The registry defines a binary PSA response threshold and a follow-up window, allowing readers to identify what was intended to be counted. But without the observed count, denominator, or uncertainty estimate, readers cannot quantify the response or judge its precision. A well-described question is not a substitute for the result needed to answer it.

The single-group design also makes the distinction between describing an outcome and estimating a treatment effect especially important. In general, a cohort’s observed outcome can be described without a control group, but a comparative claim requires an appropriate reference. A single-group response count cannot isolate the contribution of treatment from other influences. This remains true even when the endpoint is clinically meaningful or biologically relevant.

The record further shows why outcome labels need to be interpreted in context. PSA decline is a biomarker endpoint; time to radiographic disease progression and survival are separate outcomes. The endpoint description refers to associations between PSA decline and other clinical outcomes, but such context does not replace reporting results for those outcomes. Keeping the measured endpoint distinct from its proposed clinical implications helps prevent overstatement.

Safety information also needs careful framing. Counts and percentages can describe events in a treatment group, while the lack of a concurrent comparator limits conclusions about relative risk. The listed adverse-event figures are informative as descriptive registry data, but they do not by themselves establish attribution or a comparison.

Statistically, the record is a useful example of the limits imposed by incomplete outcome reporting. It permits readers to identify the design, population focus, intervention, endpoint definition, and some safety information. It does not permit a numerical estimate of the primary result, an assessment of its precision, or a causal comparison. Recognizing those boundaries is essential when interpreting registry evidence.

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 interpreting efficacy is that the numerical result for the primary endpoint is not reported in the registry record. The record gives the endpoint definition and timeframe, but not the number meeting the PSA threshold, the analysis denominator, or an uncertainty interval. The primary outcome therefore cannot be quantitatively evaluated from the listed information.

The single-group design has no listed comparator and no allocation between treatment groups. This means that the record does not support a randomized comparison or an estimate of relative treatment effect. The lack of masking is also recorded, but the registry does not describe how outcome assessment was conducted. The implications of that feature for measurement cannot be determined from the available details.

Further limitations arise from missing methodological information. Eligibility criteria, analysis populations, missing-data handling, statistical procedures, and a sample-size justification are not reported in the registry record. Although 26 participants are listed as enrolled, the number included in each outcome analysis is not stated. The record also lists 4 outcome measures but does not provide numerical results for the named secondary outcomes.

The treatment description is incomplete at its end. It specifies a starting dose and escalation schedule, but the further dose instruction is truncated in the registry record. The full dose-modification rules cannot be assessed. The registry does not report detailed event-level safety information, including timing and treatment relationship for the listed events, and it does not state the cause or treatment relationship of the recorded death.

These limitations constrain what can be concluded from the registry entry. They do not establish that outcomes were absent from the trial itself; they mean the relevant numerical and methodological details are not reported in the registry record.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Phenelzine Sulfate in Treating Patients With Non-metastatic Recurrent Prostate Cancer — NCT02217709.
• Registry record last updated 2026-06-25; status last verified 2025-11.
• Results first posted 2026-06-25.
• 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 describes a completed phase II, single-group trial sponsored by the University of Southern California, with 26 participants enrolled. The study began on 2014-09-08 and reached primary completion on 2020-06-29. Participants received phenelzine sulfate for recurrent, non-metastatic prostate cancer; the record also lists laboratory biomarker analysis and questionnaire administration.

The primary endpoint was the number of participants with a PSA decline of at least 50% from baseline following at least 12 weeks of treatment, over a timeframe of baseline to up to 12 months. Its numerical result is not reported in the registry record. Secondary outcomes include common toxicities and time to radiographic disease progression, but their numerical results are also not reported in the registry record.

The safety record lists 8 of 26 participants affected by serious adverse events, 26 of 26 affected by other adverse events, and one death. The registry lists no analysis results. The design and outcome definitions are available, but the record does not provide the primary result or the methodological detail needed to assess its precision or compare treatment outcomes.