68Ga-THP-PSMA PET/CT Imaging in High Risk Primary Prostate Cancer or Biochemical Recurrence of Prostate Cancer: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for 68Ga-THP-PSMA PET/CT Imaging in High Risk Primary Prostate Cancer or Biochemical Recurrence of Prostate Cancer (NCT03617588), a na phase 2 study. The primary outcome is Change in Patient Management.

2. Clinical Question

3. Trial Design

PRONOUNCED was a phase 2, open-label, single-group study of 68Ga-THP-PSMA PET/CT in patients with high-risk primary prostate cancer or biochemical recurrence after radical treatment. The brief summary describes it as a single-centre study in the UK. The intervention was a single intravenous administration of Gallium-68 THP-PSMA.

The brief summary describes three clinical groups. Group A comprised patients with newly diagnosed high-risk primary prostate cancer who were scheduled for radical prostatectomy. Group B comprised patients with biochemical recurrence after radical prostatectomy who were being considered for radical salvage therapy. Group C comprised patients with biochemical recurrence after radical radiotherapy, without surgery, who were being considered for radical salvage therapy. The summary describes 20 patients in each planned group, while the registry record reports enrollment of 49. It does not report the enrolled group breakdown for Groups B and C separately.

There was no randomized allocation, masking, or separate control arm. The study therefore evaluates imaging in a single-group setting; it does not provide a like-for-like comparison against another imaging strategy or a no-imaging group. The endpoint’s before-and-after management-plan assessment can describe whether intended plans changed after scans, but it does not by itself establish why a change occurred or what the clinical consequences were.

The study status is completed. The listed start date is 2018-06-18 and the primary completion date is 2019-06-12. The registry record reports a secondary safety outcome concerning treatment-emergent adverse events. It lists two outcome measures and no analyses. The record does not report a detailed statistical analysis plan or a sample-size justification.

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: Subject analysis set title: Safety Evaluable Population Subject analysis set type: Safety analysis Subject analysis set description: All patients who received a 68Ga-THP-PSMA PET/CT dose, regardless of whether they received the full intended dose, or proceeded to undergo the intended 68Ga-THP-PSMA PET/CT scan.

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 Change in Patient Management, measured over up to 3 months post PET/CT.

The primary endpoint, Change in Patient Management, measures the number of participants whose documented management plan changed after 68Ga-THP-PSMA PET/CT. The description says the analysis measured the percentage with a change by comparing the intended pre-scan plan with the revised post-scan plan. A “Yes” classification meant that any treatment option differed between the plans; “No” meant the plans were identical. The assessment timeframe was up to 3 months post PET/CT.

This endpoint is used to assess whether imaging is associated with a change in planned care. In general, a management-impact endpoint can capture whether scan findings prompt clinicians to reconsider a plan, even when the study does not compare patient outcomes between randomized groups. It is a measure of decision-making impact, not a direct measure of whether a changed plan improves outcomes.

The registry record says the endpoint was assessed in the full analysis set, with a sensitivity assessment in the per protocol population. It also states that all 49 patients underwent a technically successful post-baseline scan and that these populations were the same. The endpoint’s observed count or percentage is not reported in the registry record, so the frequency of management changes cannot be described from that record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What does the design permit?

This is a single-group, open-label study, not a randomized comparison. In general, randomization helps balance measured and unmeasured characteristics between comparison groups, while masking can reduce some influences on outcome assessment. Neither feature is listed for this study: allocation is NA and masking is none. The absence of a comparator does not prevent describing what happened after imaging, but it limits causal interpretation. A pre-scan management plan gives a within-patient reference point; it does not create the counterfactual comparison that would show what management would have been without the scan.

The groups reflect different clinical circumstances: newly diagnosed high-risk disease, biochemical recurrence after prostatectomy, and biochemical recurrence after radiotherapy without surgery. These circumstances are not interchangeable by definition, and the registry record does not report separate primary-endpoint results for them. An overall result, if reported, would describe the enrolled mix rather than establish the same management impact in each group.

How is the endpoint classified?

The endpoint compares intended and revised management plans. The registry definition assigns “Yes” when any treatment option differs and “No” when the plans remain identical. In general, a binary outcome reduces a complex decision to categories, which can make a result easy to interpret but can conceal differences in the size, direction, and clinical importance of changes. The registry record does not report more detailed categories for changed plans, so those aspects cannot be assessed.

The endpoint description refers to measuring a percentage, while the outcome is also described as a count of participants. These are two ways of expressing a binary outcome: a count records how many participants meet the definition, while a percentage expresses that count relative to the population assessed. Neither observed value is reported in the registry record. No recalculation or comparison can therefore be made from the primary outcome information in the record.

What would uncertainty measures add?

General statistical context: an estimate from a study population is subject to sampling uncertainty. A confidence interval gives a range of values compatible with the data under the method used; it does not guarantee that the true value lies in that range, and it does not resolve bias or limitations in the design. For a binary endpoint, an interval around a proportion can help show how uncertain the estimated frequency is. The registry record does not report a management-change estimate or its confidence interval, and it does not report a test result for this endpoint.

The record’s outcome population description says the full analysis set and per protocol population were the same because all 49 patients underwent a technically successful post-baseline scan. It also states that the endpoint was assessed in the full analysis set and as a sensitivity assessment in the per protocol population. A sensitivity assessment generally checks whether conclusions depend on analysis choices or population definitions. Here, according to the record, those two populations were the same; however, the primary outcome results for either assessment are not reported.

How should planning calculations be understood?

The registry record describes a planning illustration based on an observed effect, with a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. It says that the effect to detect is a stated fraction of the observed effect. Such calculations are planning illustrations, not observed power. The registry record does not report the study’s own sample-size justification, and the described illustration’s two-arm assumptions do not match the listed single-group design. No specific planning values are reported in the registry record.

General statistical context: a planning calculation asks what sample size could be needed under stated assumptions about an effect, variability, significance level, and allocation. It cannot establish that a completed study had a particular probability of detecting its actual effect. A planning result based on an observed effect is especially dependent on that estimate and its uncertainty. It should not be confused with the outcome estimate, an analysis of the study data, or evidence of efficacy.

What is missing from the statistical record?

The registry record lists no analyses and does not report the primary endpoint result, a detailed statistical analysis plan, a confidence interval, or a hypothesis test. It does not report handling of missing primary-outcome data, prespecified subgroup analyses, or interim analyses. The endpoint description notes the safety and per protocol populations, but does not supply a fuller account of the analysis procedures. Without those details, readers cannot verify the planned methods against the analyses performed or assess how alternative analysis choices might affect the result.

10. Multiplicity, Missing Data and Analysis Populations

The registry record identifies Change in Patient Management as the primary endpoint and Treatment Emergent Adverse Events as a secondary safety outcome. It lists two outcome measures, but does not report a statistical analysis plan or analyses. No multiplicity adjustment or strategy for handling multiple comparisons is reported in the registry record.

General statistical context: when a study examines several outcomes, subgroups, or comparisons, the chance of at least one apparently notable result can increase if each is assessed separately. A prespecified analysis plan can clarify which endpoint is primary, which analyses are supportive, and whether any adjustment is intended. That general concern should not be taken to mean that an unreported adjustment was or was not used in this study; the plan is not reported in the registry record.

The registry record says the primary endpoint was assessed in the full analysis set and also assessed in the per protocol population as a sensitivity analysis. It states that all 49 patients underwent a technically successful post-baseline scan and that the full analysis set and per protocol populations were the same. The endpoint result in either population is not reported.

Handling of missing primary-endpoint data is not reported in the registry record. The statement about technically successful scans does not, by itself, document completeness of every endpoint assessment or explain how any unavailable management-plan information would have been handled. Interim analyses and rules for stopping or changing analyses are also not reported. These omissions limit assessment of whether outcome selection, missingness, or analysis choices could influence the result.

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 safety figures are recorded for Group A, Groups B and C combined, and the Safety Evaluable Population. For the Safety Evaluable Population, the registry record lists 0 serious adverse events among 49 at risk, 5 other adverse events among 49 at risk, and 0 deaths. Group A has 0 serious adverse events, 2 other adverse events, and 0 deaths among 20 at risk. Groups B and C combined have 0 serious adverse events, 3 other adverse events, and 0 deaths among 29 at risk.

These are counts, not comparative risk estimates. The study has no randomized control group, so the figures cannot show whether event occurrence was higher or lower than it would have been under another strategy. The record does not list serious adverse-event terms, and the top serious terms list is empty. It also does not report whether the other adverse events were judged related to the intervention or imaging. The counts therefore describe what the registry recorded, without establishing cause or providing a comparison with untreated patients.

General statistical context: observing no recorded events does not prove that the underlying risk is zero. The precision of a safety estimate depends on the number assessed, the event definition, follow-up, and completeness of reporting. The record’s safety figures should be read as descriptive findings over the recorded study population, not as proof that serious events cannot occur.

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

The study is designed to ask whether 68Ga-THP-PSMA PET/CT is followed by a change in the documented management plan for patients with high-risk primary prostate cancer or biochemical recurrence after radical treatment. Its endpoint definition is concrete: any difference in treatment options between the intended and revised plans counts as a change. This makes the question about management decisions, rather than directly about survival, disease control, or quality of life.

The registry record does not report the primary endpoint result. It therefore cannot establish the observed frequency of management changes or indicate the precision of that estimate. The absence of that result is central: the study question can be described, but its answer cannot be inferred from the study title, design, or safety counts.

Even if a management-change result were available, the design would need to be kept in view. This is a single-group, open-label study with no randomized comparator. A change documented after a scan would show that the plan differed after imaging, according to the endpoint definition. It would not alone show that the imaging caused the difference, that the revised plan was preferable, or that patient outcomes improved.

The registry record reports no serious adverse events and no deaths in the safety groups, and it reports other adverse events. Those counts are descriptive; the record does not identify the event terms or report causality assessments. They do not establish safety relative to another imaging strategy or a control group.

General statistical context: statistical evidence addresses uncertainty within a specified design and analysis; it does not automatically answer questions outside the measured endpoint. Here, the management endpoint and adverse-event counts address different aspects of the study. Neither should be treated as a substitute for unreported patient outcomes or a comparative assessment.

13. Why This Trial Matters Statistically

This study raises a statistical question that differs from a conventional comparison of treatments: whether imaging changes a clinician’s documented management plan. That outcome can be relevant when the purpose is to understand the decision-making impact of a diagnostic procedure. Its value depends on a clear definition of change, a well-documented pre-scan plan, and a complete post-scan assessment. The registry record defines change as any difference in treatment options between intended and revised plans.

The study also illustrates why design and endpoint must be interpreted together. A within-patient comparison of plans before and after imaging can describe decision changes, but without a separate control group it does not show what would have happened without the scan. The single-group, open-label design is not a like-for-like controlled comparison. That distinction prevents a descriptive management outcome from being mistaken for proof of a causal effect or improved patient outcome.

Reporting precision matters as well. A count or percentage accompanied by an uncertainty interval would help readers judge how stable the management-change estimate might be. The registry record does not report the primary endpoint result or its uncertainty, so the central statistical question remains unanswered in the record. A study can have a clearly described endpoint and still be difficult to interpret if the corresponding result is absent.

The safety information demonstrates a related point: counts provide a useful description, but do not by themselves provide comparative evidence or establish causality. The record reports no serious adverse events and no deaths, alongside other adverse events, but supplies no event terms or comparator. Careful reading keeps these descriptive observations distinct from conclusions about relative safety.

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 principal limitation for interpreting the study is that the registry record does not report the primary management-change result. It gives the endpoint definition and assessment timeframe, but not the number or percentage classified as “Yes” or “No,” nor an uncertainty estimate. The primary question therefore cannot be answered from the record.

The single-group, open-label design has no randomized comparator, and the registry record explicitly identifies the study as not being a like-for-like control comparison. Changes in management after imaging can be described, but other explanations for a change cannot be separated from the imaging’s role using this design alone. The endpoint records plan differences, not the appropriateness or consequences of those plans.

The brief summary describes three clinical groups, but the reported enrollment does not match the planned total described in that summary. The record reports enrollment of 49, and safety figures combine Groups B and C; it does not report their separate enrolled sizes or primary-endpoint results by group. The overall management impact across these differing clinical circumstances therefore cannot be examined by subgroup from the record.

Safety reporting is limited: the record gives counts for serious and other adverse events and deaths, but does not list serious-event terms or provide event-level details or a causality assessment. The registry record also does not report a detailed statistical analysis plan, missing-data methods, multiplicity approach, interim analyses, or sample-size justification. These are limitations of what can be assessed from the registry record, not evidence that particular procedures were or were not carried out.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: 68Ga-THP-PSMA PET/CT Imaging in High Risk Primary Prostate Cancer or Biochemical Recurrence of Prostate Cancer — NCT03617588.
• Registry record last updated 2020-06-24; status last verified 2020-06.
• Results first posted 2020-06-24.
• 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

NCT03617588 is the PRONOUNCED phase 2 study of 68Ga-THP-PSMA PET/CT in high-risk primary prostate cancer or biochemical recurrence after radical treatment. The record describes an open-label, single-group study and a single intravenous administration of Gallium-68 THP-PSMA. Enrollment was 49. The listed start date is 2018-06-18, the primary completion date is 2019-06-12, and the status is completed.

The primary endpoint assessed change in patient management up to 3 months post PET/CT by comparing intended and revised plans. Its result is not reported in the registry record. The record reports 0 serious adverse events and 0 deaths in the Safety Evaluable Population, with 5 other adverse events. It lists no analyses and does not report a detailed statistical analysis plan or sample-size justification.