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 Pilot Trial of "Chemo-Switch" Regimen to Treat Advanced Melanoma (NCT00673361), a na phase 2 study. The primary outcome is Progression Free Survival (PFS).
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00673361 |
| Phase | Phase 2 |
| Condition | Melanoma |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 9 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Duke University |
| Results posted | Yes |
2. Clinical Question
Population
People with melanoma were eligible for the study. The title describes the condition as advanced melanoma, but further eligibility details and the characteristics of participants who enrolled are not reported in the registry record. The record lists enrollment of 9.
Intervention
The “chemo-switch” strategy began with concurrent decrescendo biochemotherapy and then switched to daily low-dose temozolomide plus sorafenib. The registry describes the regimen as a sequence intended to use biochemotherapy initially and then continue with the low-dose combination.
Comparator
There was no separate control group. The study is listed as single-group, with allocation recorded as NA. This means the registry record does not describe a randomized, like-for-like comparison against another treatment or a control condition.
Primary question
The primary endpoint was progression-free survival (PFS), with timeframes listed at 3 weeks, 6 weeks, 16 weeks, and 24 weeks. The record does not provide analyzed PFS results. It therefore does not establish how participants’ progression-free survival was distributed or how it compared with another group.
The broad clinical question was what effects, both good and bad, the sequential regimen had in melanoma. The registry also lists response rate by RECIST criteria as a secondary outcome. These stated questions describe what the trial set out to examine; they are not evidence that the regimen achieved tumor shrinkage, delayed progression, or changed any other outcome. Because there was no control group and the record says no data analysis was performed, the posted information cannot estimate a comparative treatment effect. Details of eligibility, the operational definitions used for outcomes, and the planned analysis are not reported in the registry record.
3. Trial Design
This was a phase II pilot trial sponsored by Duke University. The registry identifies a single-group model, allocation recorded as NA, and no masking. In practical terms, the record describes a study without a randomized comparator and without masking. The listed intervention sequence was concurrent decrescendo biochemotherapy followed by low-dose temozolomide plus sorafenib. The arm is named “Chemo-Switch” Regimen, but its arm description is blank.
The registry reports enrollment of 9. The study start is recorded as 2007-03, and primary completion as 2009-01. Its status is TERMINATED. The primary outcome description states that the study terminated before its accrual goal and that no data analysis was conducted. The target accrual and the reason for termination are not reported in the registry record.
The primary outcome is named as PFS, with assessment timeframes listed at 3 weeks, 6 weeks, 16 weeks, and 24 weeks. Response rate by RECIST criteria is listed as a secondary outcome. The registry does not provide analyzed values for either outcome. It also does not report the detailed schedule of treatment, the criteria for entering or leaving each treatment phase, the follow-up procedures, or the operational outcome-assessment rules.
As a single-group pilot, the study could describe outcomes among enrolled participants if those outcomes were collected and analyzed. It would not, by design, supply a concurrent control group for separating a regimen effect from other explanations for observed outcomes. In this case, the registry specifically says that no data analysis was performed, so even descriptive outcome estimates are not available in the 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 | "Chemo-Switch" Regimen |
|---|---|
| STARTED | 9 |
| COMPLETED | 7 |
| NOT COMPLETED | 2 |
Reasons for not completing this period:
| Reason | "Chemo-Switch" Regimen |
|---|---|
| Screen Failure | 2 |
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 | "Chemo-Switch" Regimen |
|---|---|---|
| Participants analysed | 9 | |
| Age, Customized | participants | 9 |
| Sex: Female, Male: Female | Participants | 5 |
| Sex: Female, Male: Male | Participants | 4 |
| 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 | 2 |
| Race (NIH/OMB): White | Participants | 7 |
| Race (NIH/OMB): More than one race | Participants | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| Region of Enrollment: United States | participants | 9 |
6. Primary Endpoint
The registry lists the primary outcome as Progression Free Survival (PFS), measured over 3 weeks, 6 weeks, 16 weeks, & 24 weeks.
| Element | Registry entry |
|---|---|
| Result type | N/A |
| Measure of spread | not applicable |
| Unit | not stated |
| Endpoint classification | not reduced to a single comparison |
PFS is the primary endpoint named in the registry. In general, progression-free survival measures the time participants remain alive without disease progression, according to the study’s chosen definitions and assessment procedures. It is used in clinical research because it combines information about disease progression and the time until that event, rather than describing tumor status at only one assessment. This is a general explanation; the registry does not report the precise operational definition used in this study, including how progression was determined or how events and censoring were handled.
The listed assessment timeframes are 3 weeks, 6 weeks, 16 weeks, and 24 weeks. These time points indicate when the endpoint was to be considered, but they do not themselves provide PFS results. The primary outcome description states that the study terminated before its accrual goal and had no data analysis. No estimate of PFS, event count, distribution of follow-up, confidence interval, or comparison is reported in the registry record.
PFS can be useful when a study aims to characterize how long disease control persists, but interpretation depends on consistent assessment, complete follow-up, clear event definitions, and appropriate handling of participants whose event status is unknown at the end of observation. Those details are not reported in the registry record. Consequently, the endpoint’s name and timeframes should not be mistaken for evidence of an observed benefit or a measured duration of disease control in this trial.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The central statistical fact is that the registry explicitly describes the study as terminated before its accrual goal, with no data analysis. Although enrollment is listed as 9, the record contains no analyzed PFS result and no response-rate result. It therefore supports no estimate of the regimen’s effect on either endpoint. The listed PFS timeframes do not substitute for outcome values, and the record does not report the number of progression events or the time participants were followed.
There is also no randomized or parallel control group. Even if outcome summaries had been reported, a single-group study would not directly estimate the difference between this regimen and an alternative. General statistical interpretation of an uncontrolled outcome must allow for other explanations, such as the characteristics of enrolled participants, the course of the disease, and the way outcomes are observed. The registry does not provide enough information to assess those factors in this study.
A confidence interval is a statistical range that communicates uncertainty around an estimated quantity; it is not a guarantee that the true value lies within a particular range. No confidence interval or other uncertainty estimate for PFS or response is reported in the registry record. Likewise, no p-value, effect estimate, or formal hypothesis-test result is reported. Without an analyzed estimate, the precision of the clinical outcomes cannot be judged.
The safety counts are distinct from efficacy results. For the “Chemo-Switch” Regimen group, the registry lists 9 participants at risk for serious adverse events and 0 affected. It also lists 9 at risk for other adverse events and 0 affected. These are the posted counts; they do not supply detailed event descriptions or establish the absence of risk. Deaths are not reported in the record. The safety information cannot fill the gap left by the absent outcome analysis.
In statistical terms, the record documents a planned question and limited enrollment, but not an analyzed answer. It would be inappropriate to interpret the absence of reported PFS and response estimates as evidence that outcomes were favorable, unfavorable, or unchanged. The registry’s explicit statement that no analysis was performed is the key limit on interpretation. Any conclusion about treatment effects, comparative effectiveness, or the precision of outcomes would go beyond what the posted results support.
9. Statistical Methods Explained
The methods that can be described from the registry are limited. The study is identified as phase II, pilot, single-group, and unmasked, with allocation recorded as NA. It lists enrollment of 9 and names PFS as the primary outcome. The outcome description says that the study terminated before its accrual goal and had no data analysis. The statistical analysis plan, the rationale for the accrual goal, and any planned model or estimation procedure are not reported in the registry record.
What does a single-group design estimate?
In general, a single-group study can describe outcomes observed among participants who receive the study regimen. It does not provide a concurrent untreated or alternative-treatment group. Without such a comparator, an outcome observed after treatment cannot by itself isolate the contribution of the regimen from other influences. A controlled comparison can address a different question: how outcomes differ between groups assigned or otherwise exposed to distinct strategies. This general distinction is especially important when interpreting a trial whose registry record does not report an analysis.
How is PFS usually analyzed?
As a general statistical approach, time-to-event outcomes such as PFS are often analyzed with methods that account for differing follow-up times and participants whose event has not been observed by the end of follow-up. A survival curve can describe the estimated probability of remaining event-free over time. A confidence interval can communicate uncertainty around such an estimate. A comparative model may be used when a suitable comparison group and analysis plan exist. These are general methods, not methods documented for this trial. The registry does not report a survival curve, event counts, estimates, confidence intervals, a comparative model, or the treatment of censoring.
Why does follow-up and censoring matter?
In general, a participant who has not had a recorded event by the end of available observation does not necessarily have an event-free outcome indefinitely. The observation may simply end before an event is documented. Time-to-event methods represent the observed follow-up while accounting for that incomplete event information under assumptions about how observation ends. Their interpretation depends on reliable event ascertainment and appropriate handling of participants who leave follow-up. The registry does not describe follow-up completeness, loss to follow-up, censoring rules, or missing outcome handling, so those assumptions cannot be evaluated for this study.
What does the record say about testing and precision?
No inferential analysis is reported. That means the registry provides no tested hypothesis, p-value, effect estimate, or confidence interval for PFS or response rate. Statistical significance, in general, refers to the compatibility of data with a specified statistical model and null hypothesis; it is not a measure of clinical importance, and it cannot be assessed without the relevant analysis. Precision likewise depends on an estimate and its uncertainty, neither of which is reported for the clinical outcomes.
The registry lists two outcome measures, including primary PFS and secondary response rate by RECIST criteria. The listing identifies outcomes of interest, not analyzed findings. The detailed definition of response, assessment rules, analysis population, and approach to multiple outcome testing are not reported in the registry record. It would be inappropriate to infer that particular statistical methods were used simply because these endpoints were named.
How should pilot status be understood?
In general, a pilot study may be used to explore whether a larger research effort is feasible or to obtain preliminary descriptive information. The term does not by itself establish the study’s objectives, statistical plan, or the suitability of its results for estimating treatment effects. Here, the record calls the study a pilot and states that it terminated before the accrual goal, but does not report the goal, its justification, or feasibility criteria. It also explicitly states that no data analysis was performed. Thus, the registry cannot support a claim that the study demonstrated feasibility or generated an outcome estimate.
The study’s enrollment of 9 is the number recorded as enrolled, not a basis for claiming adequate or inadequate power. No power calculation or sample-size justification is reported in the registry record. General sample-size calculations depend on assumptions about the outcome, the effect to be detected, variability or event rates, and the analysis design. Without documented trial-specific assumptions and a completed analysis, no conclusion about the study’s ability to detect an effect is justified. Planning illustrations, where present in statistical materials, should not be confused with observed power or with an analysis of participants’ outcomes.
10. Multiplicity, Missing Data and Analysis Populations
The registry identifies PFS as the primary outcome and response rate by RECIST criteria as a secondary outcome. It does not report an analysis for either measure. The statistical approach to handling multiple outcomes or multiple assessments is not reported in the registry record. In general, testing several outcomes or repeatedly examining results can increase the chance of a false-positive finding if the testing strategy is not addressed. Whether an adjustment was planned or used cannot be determined from this record, and no p-values or outcome estimates are available to interpret in any case.
Missing-data procedures and the analysis population are also not reported in the registry record. The record does not state whether all enrolled participants were intended for a particular analysis, how participants with incomplete follow-up would be handled, or whether any outcome data were unavailable. The statement that no data analysis was performed means that no analyzed population or missing-data method can be evaluated from the posted results.
For time-to-event outcomes, general methods can use partial follow-up, but their interpretation depends on event definitions, follow-up completeness, and censoring assumptions. Those features are not described for this trial. The listed PFS timeframes do not reveal whether assessments occurred for every participant or how incomplete observations were handled. The absence of this information is a reporting limitation; it does not establish that data were missing or that a particular method was omitted from the original protocol.
No interim analysis plan, stopping rule, or multiplicity procedure is reported in the registry record. The reason for termination is also not reported. The record states only that the study terminated before its accrual goal and had no data analysis. These omissions limit evaluation of the study’s statistical conduct, but they should not be filled by assumptions about what the protocol may have specified.
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 |
|---|---|---|---|
| "Chemo-Switch" Regimen | 0 | 9 | 0.0% |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 5% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| "Chemo-Switch" Regimen | 0 of 9 |
For the “Chemo-Switch” Regimen group, the registry lists 9 participants at risk for serious adverse events and 0 affected. It also lists 9 participants at risk for other adverse events and 0 affected. These counts describe the entries in the safety record; they are not a detailed account of the types, timing, duration, or severity of individual events. The record lists no top serious adverse event terms.
A zero count in a small enrolled group does not establish that an intervention has no risk. It indicates that the registry reports no affected participants in the listed categories for this group. General interpretation of safety counts also depends on how events were defined, collected, and followed, and on the amount of exposure and observation. Those details are not reported in the registry record. Deaths are not reported in the registry record; a missing death count should not be read as a count of zero.
These safety figures should also be kept separate from the unreported PFS and response outcomes. They do not provide evidence about tumor response or progression-free survival. Since the study is single-group and the record reports no outcome analysis, the counts cannot support a comparison of safety between regimens or a precise estimate of event risk.
12. What the Result Does, and Does Not, Mean
The registry record establishes that a phase II pilot study of a sequential “chemo-switch” regimen was conducted as a single-group study, enrolled 9, and was terminated before its accrual goal. It identifies PFS as the primary endpoint and response rate by RECIST criteria as a secondary outcome. The primary outcome description explicitly states that no data analysis was performed. As a result, the record does not report an analyzed estimate of PFS, response rate, or a treatment effect.
That absence is not a result showing that the regimen succeeded, failed, or had no effect. It means that the posted record does not give analyzed efficacy results with which to answer those questions. It also does not establish whether outcome information was collected but left unanalyzed, or whether particular outcome data were unavailable; those details are not reported in the registry record.
The single-group design places a further limit on what the study could establish. Without a concurrent comparator, an observed outcome could not directly quantify how the regimen performed relative to another treatment strategy. In this case, even a descriptive summary of observed efficacy outcomes is not reported. No confidence interval or other measure of precision is given, so the amount of uncertainty around any clinical outcome cannot be evaluated.
The safety entries report 0 affected participants for serious adverse events and 0 affected for other adverse events among 9 at risk in each category. These counts should be interpreted as recorded counts, not as proof that the regimen carries no risk. The record does not give event details, and deaths are not reported. Overall, the posted information describes the trial’s design, enrollment, termination, and limited safety counts, but it does not supply an analyzed clinical outcome or a basis for a comparative conclusion.
13. Why This Trial Matters Statistically
This trial is statistically important as an example of the difference between a study question and an analyzed answer. The registry names a primary endpoint, gives assessment timeframes, and lists a secondary response outcome. Those entries communicate what outcomes the study intended to examine, but the record states that no data analysis was performed. Without outcome estimates, the statistical questions of effect size and precision remain unanswered.
The record also illustrates why design matters when interpreting a clinical outcome. A single-group study can describe participants’ outcomes if analyzed, but it does not provide a concurrent reference group for a treatment comparison. This design limitation is separate from the absence of analysis: even a complete descriptive analysis would not create a randomized comparison. Here, the lack of reported outcome analysis means that neither descriptive efficacy estimates nor comparative estimates are available.
Enrollment and termination status are relevant to how much can be learned, but enrollment alone does not establish whether a study was sufficiently informative. The accrual goal, its justification, and any power assumptions are not reported in the registry record. The explicit statement that the trial ended before its goal gives context, while the absence of analysis prevents assessment of the outcomes that motivated the study.
Finally, the safety counts show why counts need context. The record reports zero affected participants in the listed serious and other adverse-event categories, but provides no event terms and does not report deaths. A small set of counts cannot establish the absence of risk or describe the range of possible events. Careful statistical reading therefore depends not only on numerical entries, but also on study design, analysis, uncertainty, and completeness of reporting.
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 states that the trial terminated before its accrual goal and had no data analysis. It reports enrollment of 9, but no analyzed PFS or response results. The accrual goal and reason for termination are not reported in the registry record. Without outcome estimates, there is no basis for judging the magnitude or precision of clinical outcomes.
The single-group design does not include a control group, and allocation is recorded as NA. The study therefore cannot provide a randomized, like-for-like comparison. The record also lists no masking. It does not report details about outcome assessment, participant follow-up, or adherence to the treatment sequence.
For the primary endpoint, the registry supplies the name PFS and timeframes of 3 weeks, 6 weeks, 16 weeks, and 24 weeks, but does not report the operational definition, event counts, censoring method, or any estimate. For response rate, RECIST criteria are named, but analyzed results and further assessment details are not reported. The analysis population, missing-data methods, and approach to multiple outcomes are not reported in the registry record.
The safety information is limited to the recorded at-risk and affected counts. Serious and other adverse-event details are not listed, and deaths are not reported. The registry does not provide enough information to evaluate exposure duration, completeness of safety follow-up, or the process used to collect events. These limitations concern what can be learned from the record; they should not be taken as evidence that unreported methods or data were necessarily absent from the original study materials.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Pilot Trial of "Chemo-Switch" Regimen to Treat Advanced Melanoma — NCT00673361.
- Registry record last updated 2016-01-13; status last verified 2012-12.
- Results first posted 2013-04-26.
- 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
The registry describes a phase II pilot trial of a sequential “chemo-switch” regimen for advanced melanoma. The intervention began with concurrent decrescendo biochemotherapy and switched to daily low-dose temozolomide plus sorafenib. The design is listed as single-group, with allocation recorded as NA and masking as none. Enrollment was 9; the recorded start was 2007-03 and primary completion was 2009-01.
The study status is TERMINATED. Its primary outcome was PFS, with listed timeframes of 3 weeks, 6 weeks, 16 weeks, and 24 weeks; response rate by RECIST criteria was a secondary outcome. The registry says the study terminated before its accrual goal and that no data analysis was performed. No analyzed efficacy estimates are reported. The safety record lists 0 affected participants for serious adverse events and 0 for other adverse events among 9 at risk in each category. Deaths are not reported in the registry record.