This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for NaF Positron Emission Tomography/Computed Tomography (PET/CT)Imaging to Assess Treatment Responsiveness to TAK-700 in Patients With Castrate Resistant Prostate Cancer (CRPC) With Bone Metastasis (NCT01816048), a na phase 2 study. The primary outcome is Number of Participants With a Change in Maximum NaF PET/CT Standardized Uptake Values.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01816048 |
| Phase | Phase 2 |
| Condition | Prostatic Neoplasms, Prostate Cancer |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 8 |
| Arms in the primary outcome | n/a |
| Lead sponsor | University of Wisconsin, Madison |
| Results posted | Yes |
2. Clinical Question
Population
Participants had metastatic castrate resistant prostate cancer with bone metastasis. The registry record says the study closed early: 8 of 20 planned participants were enrolled, and only 4 completed the week 12 scan. The record does not describe further eligibility details or the characteristics of the enrolled participants.
Intervention
TAK-700 was administered orally at 300 mg twice daily, continuously on 28-day treatment cycles. NaF PET/CT imaging was used to assess bone metastases. The stated primary assessment compares the maximum standardized uptake value before dosing with the value 12 weeks after starting TAK-700.
Comparator
There was no separate control group: the registry describes a single-group study, with allocation listed as not applicable and no masking. The primary comparison is within participants, between baseline and follow-up imaging. It is not a randomized comparison of TAK-700 against another treatment or against no treatment.
Primary question
The primary question was how many participants had a change in maximum NaF PET/CT standardized uptake values from baseline to 3 months. This is a pharmacodynamic imaging question: it concerns whether the imaging measure changes during treatment. The registry record does not report the observed count, the direction or magnitude of changes, or an analysis of the primary endpoint.
3. Trial Design
This was a phase 2, single-group study sponsored by the University of Wisconsin, Madison. The registry lists allocation as not applicable and masking as none. The design therefore does not include a randomized control group or blinded treatment assignment. Its stated focus was assessing whether NaF PET/CT scans could evaluate response in bone metastases among participants treated with TAK-700.
TAK-700 was described as an oral drug administered at 300 mg twice daily continuously on 28-day treatment cycles. The study also involved fluorine F 18 sodium fluoride and PET and CT procedures. The registry lists the primary endpoint timeframe as baseline and 3 months, and its endpoint description specifies comparison with imaging 12 weeks after starting treatment.
The study started in 2013-05, with primary completion in 2015-12. Its status is terminated. The record states that 8 of 20 planned participants were enrolled and that only 4 completed the week 12 scan. It does not report why the study was terminated, why enrollment stopped, or why some participants did not complete that scan.
Additional listed outcomes include adverse events, PSA kinetics, changes in NaF PET/CT, clinical outcomes such as RECIST and radiographic progression-free survival, and circulating tumor cell measures. The registry lists 10 outcome measures but no analyses. The statistical analysis plan, allocation concealment procedures, and any interim-analysis plan are not reported in the registry 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.
Overall Study
| Stage | TAK-700 |
|---|---|
| STARTED | 8 |
| COMPLETED | 2 |
| NOT COMPLETED | 6 |
Reasons for not completing this period:
| Reason | TAK-700 |
|---|---|
| Adverse Event | 1 |
| Death | 1 |
| Withdrawal by Subject | 1 |
| Disease Progression | 3 |
Analysis population for the primary outcome, as defined in the registry: The study closed early so only 8 of 20 planned were enrolled and of the 8, only 4 completed the week 12 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.
| Characteristic | Unit | TAK-700 |
|---|---|---|
| Participants analysed | 8 | |
| Age, Categorical: <=18 years | Participants | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 2 |
| Age, Categorical: >=65 years | Participants | 6 |
| Sex: Female, Male: Female | Participants | 0 |
| Sex: Female, Male: Male | Participants | 8 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 0 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 8 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 |
| Race (NIH/OMB): Asian | Participants | 0 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 |
| Race (NIH/OMB): Black or African American | Participants | 0 |
| Race (NIH/OMB): White | Participants | 8 |
| Race (NIH/OMB): More than one race | Participants | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| Region of Enrollment: United States | participants | 8 |
6. Primary Endpoint
The registry lists the primary outcome as Number of Participants With a Change in Maximum NaF PET/CT Standardized Uptake Values, measured over Baseline and 3 months.
| Element | Registry entry |
|---|---|
| Result type | Count Of Participants |
| Measure of spread | not applicable |
| Unit | Participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint is the number of participants with a change in maximum NaF PET/CT standardized uptake values, or SUVmax, between baseline and 3 months. The endpoint description defines the change as the value at three months minus the value at baseline, with the follow-up scan described as 12 weeks after treatment starts. The registry record does not define what size of difference counts as a change, or report the number of participants who met such a definition.
In general, a standardized uptake value is a quantitative way to describe tracer uptake in an image. SUVmax refers to the maximum such value used in the assessment. NaF PET/CT is relevant to this question because the study targets imaging of bone metastases; the endpoint asks whether the imaging measure changes over the treatment period. A change in an imaging measure is a pharmacodynamic observation, not by itself a direct measure of symptoms, survival, or overall clinical benefit.
For interpretation, it matters that the endpoint is expressed as a count of participants with a change, rather than a reported average change in SUVmax. The registry does not provide individual measurements, a summary of the amount of change, a threshold for classifying change, or uncertainty around the endpoint. It also reports that only 4 participants completed the week 12 scan, limiting the information available for the planned follow-up assessment.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record establishes the study question and the extent of follow-up, but it does not provide a primary endpoint result. It does not report how many participants had a change in SUVmax, whether uptake increased or decreased, or the size of any changes. No estimate of uncertainty, statistical test, or analysis result is listed. Consequently, the record does not support a quantitative conclusion about the imaging endpoint.
The available completion information is important context. The study enrolled 8 of 20 planned participants, and only 4 completed the week 12 scan. The primary question depends on comparing baseline and follow-up imaging. When follow-up measurements are unavailable for some participants, the number with a recorded change cannot automatically be treated as representing everyone enrolled. The registry record does not explain why scans were not completed or how missing measurements were handled.
There was no randomized control group. Any change between baseline and follow-up would therefore be a within-participant observation during treatment, not a randomized estimate of the effect of TAK-700 relative to another treatment or to no treatment. General statistical interpretation: without a concurrent comparison group, observed changes can also reflect time, measurement variability, other care, or other influences. The record does not provide information that would separate these possibilities.
The registry lists secondary outcomes that include PSA kinetics, RECIST, radiographic progression-free survival, adverse events, and circulating tumor cell measures. Listing an outcome does not establish that it was analyzed or that a result was observed. The record lists 10 outcome measures and 0 analyses, and does not report results for these secondary measures. Their presence in the outcome list should not be read as evidence of a particular response or association.
For safety, the registry reports serious adverse event figures for the TAK-700 group and names serious event terms with percentages. These are descriptive safety data, not a comparison against a control group. The figures do not establish whether an event was caused by treatment. The record does not provide the event-level details needed to judge timing, severity beyond the serious classification, or clinical course.
Overall, the posted record is most informative about the study design, early closure, and limited completion of the planned scan. It does not report the primary imaging result or statistical analyses. Those omissions mean the endpoint's direction, magnitude, precision, and relationship to other outcomes are not reported in the registry record.
9. Statistical Methods Explained
What does the endpoint count? The primary endpoint is a count of participants with a change in SUVmax from baseline to follow-up. This is not the same as reporting the average change in SUVmax, the distribution of individual changes, or the proportion with an increase or decrease. The registry record does not state the rule used to classify a measurement as a change. It also does not report the endpoint count or a method for estimating its uncertainty.
How does the within-participant comparison work? In general, a baseline-to-follow-up imaging assessment uses measurements from the same participant at different times. This pairing can be useful because each participant serves as their own reference for change. A suitable analysis would need to respect that the measurements are linked within a participant rather than treating them as independent observations. The registry describes the time points but does not report the statistical method used for this comparison.
What can a confidence interval tell a reader? General statistical explanation: a confidence interval describes uncertainty around an estimate under the assumptions of the method used. A narrow interval indicates greater precision than a wide interval, while neither interval alone establishes that a result is clinically meaningful. No confidence interval for the primary endpoint is reported in the registry record, so the precision of any endpoint estimate cannot be assessed from the record.
What can a p-value tell a reader? General statistical explanation: a p-value summarizes how compatible data are with a specified null hypothesis under the model and assumptions used. It does not measure the size or importance of an effect, nor does it establish causality. The registry record lists no primary analysis or p-value. It is therefore not possible to describe statistical evidence for a change from the posted record.
How does the design affect interpretation? This is a single-group, unmasked study without a randomized control group. General statistical point: a within-group change can describe what happened over time among observed participants, but does not isolate treatment effects from other time-related or measurement influences. Randomization and a concurrent comparison group can help address some of those alternative explanations. They are not part of the design described in this record.
What does limited scan completion mean? The record reports 8 enrolled participants and 4 who completed the week 12 scan. General statistical explanation: missing follow-up can affect an estimate if the availability of measurements is related to participants' outcomes or other relevant characteristics. Even when missingness is unrelated to the outcome, fewer observed measurements generally leave less information for estimating a result. The record does not report reasons for missing scans, comparisons of participants with and without follow-up, or a missing-data method.
How should planning estimates be understood? General explanation: a sample-size calculation is a planning illustration based on assumptions about the effect to detect, variability, significance level, allocation, and analysis method. It is not an observed result and is not observed power. The planning assumptions described for this record use a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation, with the detectable effect expressed as a fraction of the observed effect. The actual study is single-group, so those planning assumptions do not describe its design. The registry record does not report the study's own sample-size justification or the observed primary effect on which a recalculation could be based.
What is over-dispersion, in general? For count outcomes, over-dispersion means the observed variability is greater than a chosen statistical model expects. If a model assumes less variability than the data contain, uncertainty may be understated. This endpoint is a count of participants with a change, but the record does not report a count model, evidence of over-dispersion, or a statistical analysis. Over-dispersion should therefore be treated as a general modeling consideration, not as a feature established for this study.
What does the outcome list say about analysis? The registry lists 10 outcome measures and 0 analyses. Outcomes can be prespecified or listed without having a reported analysis in the available record. The presence of a named outcome does not disclose its model, analysis population, handling of missing data, or whether adjustments were made. Those statistical details are not reported in the registry record.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists 10 outcome measures, including the primary imaging endpoint and secondary outcomes involving adverse events, PSA kinetics, NaF PET/CT findings, clinical outcomes, and circulating tumor cells. When several outcomes are considered, there can be more opportunities to observe an apparently notable result by chance. General statistical explanation: multiplicity procedures can control or describe this issue, but their choice depends on the analysis plan and the purpose of the comparisons.
The record lists 0 analyses and does not report whether multiplicity was considered, whether any outcome hierarchy was used, or whether adjustment was planned. No interpretation of adjusted or unadjusted statistical significance is possible from the record. The presence of multiple listed outcomes is not itself evidence that formal testing occurred.
Missing follow-up is particularly relevant to the primary endpoint. The record says 8 of 20 planned participants were enrolled and only 4 completed the week 12 scan. It does not say why the remaining enrolled participants lacked that scan, whether baseline imaging was available for all participants, or how incomplete endpoint data were handled. The analysis population and rules for including participants in each outcome are not reported in the registry record.
General statistical explanation: complete-case analysis uses only participants with the required measurements. Other approaches may be considered when measurements are missing, but they rely on assumptions that should be stated and justified. No missing-data method is reported, so neither the approach nor the assumptions can be evaluated.
11. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| TAK-700 | 4 | 8 | 50.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| TAK-700 | 1 of 8 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| TAK-700 | 8 of 8 |
Most frequent serious adverse event terms
| Event term | Organ system | TAK-700 |
|---|---|---|
| Dehydration | Gastrointestinal disorders | 1 of 8 |
| Diarrhea | Gastrointestinal disorders | 1 of 8 |
| Dyspnea | Respiratory, thoracic and mediastinal disorders | 1 of 8 |
| Hypokalemia | Metabolism and nutrition disorders | 1 of 8 |
| Left ventricular systolic dysfunction | Cardiac disorders | 1 of 8 |
| Nerve impingement | Nervous system disorders | 1 of 8 |
| Urinary tract infection | Infections and infestations | 1 of 8 |
| sudden death | General disorders | 1 of 8 |
Most frequent non-serious adverse event terms
| Event term | Organ system | TAK-700 |
|---|---|---|
| Nausea | Gastrointestinal disorders | 7 of 8 |
| Anorexia | Gastrointestinal disorders | 5 of 8 |
| Back pain | Musculoskeletal and connective tissue disorders | 4 of 8 |
| Fatigue | General disorders | 4 of 8 |
| Headache | Nervous system disorders | 4 of 8 |
| Hypokalemia | Metabolism and nutrition disorders | 4 of 8 |
| Hypertension | Vascular disorders | 3 of 8 |
| Insomnia | Psychiatric disorders | 3 of 8 |
| Pain | General disorders | 3 of 8 |
| Weight loss | Investigations | 3 of 8 |
Serious events with the highest arm-level rate: dehydration (12.5%), diarrhea (12.5%), dyspnea (12.5%), hypokalemia (12.5%), left ventricular systolic dysfunction (12.5%).
The registry reports serious adverse event figures for the TAK-700 group: 8 participants were listed as at risk and 4 as affected. It also reports 8 at risk for other adverse events and 8 affected, with 1 death. These are registry counts, not estimates from a randomized comparison. The record does not give event timing, participant-level detail, or the relationship of each event to treatment.
The listed serious adverse event terms are dehydration, diarrhea, dyspnea, hypokalemia, left ventricular systolic dysfunction, and nerve impingement; each is reported as 12.5%. The registry record does not explain the denominator used for these percentages or whether participants could be represented under more than one term. The terms should not be added together, and their percentages should not be interpreted as mutually exclusive categories.
General statistical explanation: safety counts describe events observed and recorded during the defined reporting period. A serious adverse event is not necessarily caused by the study treatment, and a count alone does not convey duration, severity details, or clinical course. Because this study has no control group, the registry figures cannot provide a like-for-like estimate of comparative risk.
12. What the Result Does, and Does Not, Mean
The study addresses whether NaF PET/CT imaging can be used to assess changes in bone metastases during treatment with TAK-700. Its primary endpoint focuses on the number of participants with a change in SUVmax between baseline and 3 months. This is a measurement-focused question about imaging response, rather than a direct endpoint of survival, symptoms, or quality of life.
The registry record does not report the primary endpoint result. It therefore does not establish whether SUVmax changed, in which direction it changed, how large any changes were, or how precise an estimate might be. The record also does not provide a reported analysis linking imaging changes with the listed clinical outcomes or circulating tumor cell measures.
Even if a before-and-after change had been reported, general statistical interpretation would require care. Without a randomized control group, changes over time cannot by themselves distinguish treatment-related effects from other influences or measurement variation. The small amount of completed follow-up further limits how confidently an observed pattern could characterize the intended population. The registry does not report enough detail to assess missingness or the representativeness of participants who completed the scan.
The study's early closure and limited scan completion are important details about the evidence available in the record, but they do not explain why the study stopped or predict what a completed study would have found. The registry record does not report the reason for termination. It also does not report the study's statistical plan, endpoint analysis, or results for the listed secondary outcomes.
Accordingly, the record supports a description of the study question and design, but not a conclusion about the imaging endpoint or comparative treatment effects. The reported safety counts can be read descriptively, with no control-group comparison and no basis in the record for assigning causation.
13. Why This Trial Matters Statistically
This study is statistically notable because it asks whether an imaging measure can track change in bone metastases while participants receive an investigational drug. Such a question separates a measurement or pharmacodynamic aim from a treatment-comparison aim. The primary endpoint is a participant count based on change in SUVmax, rather than a reported clinical outcome or a randomized estimate of treatment effect.
The single-group design shapes what the data could establish. A baseline-to-follow-up comparison can describe change among participants with observed scans, but it cannot by itself show what would have happened over the same period without TAK-700. An appropriate comparison group and a clear analysis plan would be needed to answer a causal treatment question more directly.
Completion is another central statistical issue. The study enrolled 8 of 20 planned participants, and only 4 completed the week 12 scan. A planned imaging endpoint depends on usable follow-up. Limited completion reduces the available information and raises questions about missing measurements, yet the registry record does not report reasons for noncompletion or the method used to address missing data.
Finally, the record lists several secondary outcome areas but no analyses. This illustrates why an outcome list and an analysis result are different kinds of information. Statistical interpretation requires estimates, uncertainty, methods, and clear definitions of the analyzed population, none of which are reported for the primary endpoint in this 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.
The most direct limitation is that the registry record does not report the primary endpoint result. It gives the endpoint definition and timing but no count of participants with a change, no magnitude or direction of change, and no uncertainty estimate. The record also does not specify the threshold used to classify an SUVmax value as changed.
Follow-up was limited: 8 of 20 planned participants were enrolled, and only 4 completed the week 12 scan. The reasons for early closure and incomplete scan completion are not reported. Nor does the record describe how missing primary endpoint measurements were handled or define the analysis population.
The study had a single group, no masking, and no randomized control group. These features limit causal interpretation and leave the observed before-and-after comparison vulnerable to influences not separated by the design. The record does not report participant characteristics or enough detail to assess how well the enrolled participants represent the intended population.
The registry lists 10 outcome measures but 0 analyses. It does not report a statistical analysis plan, multiplicity approach, or results for the secondary outcomes. The safety summary does not provide event-level timing or the denominator behind the listed serious-event percentages. The record also does not report the reason for termination, the study's sample-size justification, or interim analyses.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: NaF Positron Emission Tomography/Computed Tomography (PET/CT)Imaging to Assess Treatment Responsiveness to TAK-700 in Patients With Castrate Resistant Prostate Cancer (CRPC) With Bone Metastasis — NCT01816048.
- Registry record last updated 2019-12-09; status last verified 2017-12.
- Results first posted 2017-07-19.
- 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.
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18. Record Summary
NCT01816048 is a phase 2, single-group study sponsored by the University of Wisconsin, Madison, of TAK-700 and NaF PET/CT imaging in metastatic castrate resistant prostate cancer with bone metastasis. TAK-700 was administered at 300 mg orally twice daily on continuous 28-day treatment cycles. The primary endpoint was the number of participants with a change in SUVmax from baseline to 3 months.
The study started in 2013-05, had primary completion in 2015-12, and is listed as terminated. The record states that 8 of 20 planned participants were enrolled and only 4 completed the week 12 scan. It lists 10 outcome measures and 0 analyses. The primary endpoint result, analysis methods, reasons for termination, and handling of missing data are not reported in the registry record.