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 Sorafenib in Treating Patients With Advanced Anaplastic Thyroid Cancer (NCT00126568), a na phase 2 study. The primary outcome is Number of Patients With Response to Treatment Measured by RECIST Criteria.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00126568 |
| Phase | Phase 2 |
| Condition | Anaplastic Thyroid Cancer, Recurrent Thyroid Cancer |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 20 |
| Arms in the primary outcome | n/a |
| Lead sponsor | National Cancer Institute (NCI) |
| Results posted | Yes |
2. Clinical Question
Population
The trial concerned patients with advanced anaplastic thyroid cancer. The primary endpoint population was all patients who received at least one cycle of treatment. The registry record lists an enrollment of 20 participants, but does not report how many received a cycle or provide further details about their clinical characteristics.
Intervention
Participants received oral sorafenib tosylate. Treatment was given twice daily on days 1-28, with courses repeating every 28 days if disease had not progressed and unacceptable toxicity had not occurred.
Comparator
This was a single-group study, with no concurrent control group described. Allocation is recorded as not applicable, and masking was none. The registry record therefore does not describe a randomized comparison with another treatment or with a control condition.
Primary question
The primary question was how many treated participants had a response according to RECIST criteria at 6 months after treatment. The record describes the response categories and lesion measurement rules, but does not report the number of participants who met a stated responder definition. Consequently, the primary response result cannot be quantified from the registry record.
3. Trial Design
This was a phase II trial of sorafenib tosylate in patients with advanced anaplastic thyroid cancer. It used a single-group model, with no masking. Allocation is listed as not applicable, consistent with the absence of a randomized treatment comparison. The registry lists an enrollment of 20 participants. That enrollment figure does not establish how many participants received treatment or contributed to each outcome.
The treatment was oral sorafenib twice daily on days 1-28. Courses were to repeat every 28 days in the absence of disease progression or unacceptable toxicity. The primary endpoint population was described as all patients who received at least one cycle. This definition is narrower than an analysis population that automatically includes every enrolled participant, and the record does not state how many participants met it.
The recorded start was 2005-06 and primary completion was 2011-09. The trial status is terminated. The reason for termination, whether recruitment or follow-up ended as planned, and the timing of termination relative to the stated primary completion are not reported in the registry record. The status alone does not explain why the trial stopped.
Progression-free survival, overall survival, and adverse events were listed as secondary outcomes. The record describes progression-free survival as measured from treatment outset to disease progression, and overall survival as measured from treatment outset to death. Numerical results for these time-to-event outcomes are not reported in the registry record. The record also lists four outcome measures and zero analyses. Those entries do not establish that no analyses were performed; they indicate that analysis details are not recorded there.
Because this is a single-group study, the findings can describe outcomes among treated participants but cannot by themselves separate treatment effects from the natural course of disease, participant selection, or other influences. A comparison with another group is not part of the recorded design.
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 | BAY 43-9006 |
|---|---|
| STARTED | 20 |
| COMPLETED | 18 |
| NOT COMPLETED | 2 |
Reasons for not completing this period:
| Reason | BAY 43-9006 |
|---|---|
| Death | 2 |
Analysis population for the primary outcome, as defined in the registry: All patients that received at least one cycle of treatment
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 | BAY 43-9006 |
|---|---|---|
| Participants analysed | 20 | |
| Age, Continuous | years | 59 (28 to 79) |
| Sex: Female, Male: Female | Participants | 7 |
| Sex: Female, Male: Male | Participants | 13 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 0 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 17 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 3 |
| 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 | 20 |
| Race (NIH/OMB): More than one race | Participants | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| Region of Enrollment: United States | participants | 20 |
6. Primary Endpoint
The registry lists the primary outcome as Number of Patients With Response to Treatment Measured by RECIST Criteria, measured over at 6 months after treatment.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint was the number of patients with a response to treatment measured by RECIST criteria at 6 months after treatment. It is a count endpoint: it concerns how many participants meet the endpoint definition, rather than a continuous measurement such as change in tumor size. The population specified for this outcome includes all patients who received at least one cycle of treatment.
The registry describes response evaluation using the Response Evaluation Criteria in Solid Tumors committee criteria. It names complete response, stable disease, partial response, and progressive disease, and says that best response depends on achievement of measurement and confirmation criteria. The record does not state which of these categories qualified as a response for the primary count. That missing operational detail matters because a count requires a clear rule for classifying participants as responders or nonresponders.
The lesion measurement description specifies measurable lesions as accurately measurable in at least one dimension, with the longest diameter recorded, and gives thresholds of >20 mm using conventional techniques or >10 mm using spiral CT. These are registry definitions, not outcome results.
General: A response count can provide an interpretable summary of tumor response at a specified assessment time. Its interpretation depends on the assessment rules, the number assessed, and the handling of participants with missing evaluations or early discontinuation. Those details, as well as the response count itself, are not reported in the registry record. The endpoint therefore identifies what was intended to be measured, but the posted information does not show the observed response frequency or its precision.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies response at 6 months after treatment as the primary endpoint and lists 20 participants as enrolled. It does not report the number with a response, the number assessed for the primary endpoint, or a response estimate. There is therefore no numerical primary result to interpret and no basis in the recorded information for describing the observed response frequency or its precision.
The endpoint population is defined as all patients who received at least one cycle, but the number meeting that definition is not reported. Enrollment and analysis populations should not be treated as interchangeable: some enrolled participants may not have received treatment or may not have had an evaluable assessment. The record does not state whether that occurred or how such cases were handled.
Progression-free survival and overall survival are listed as secondary outcomes, along with adverse events. Their measurement origins are described, but numerical survival estimates, event counts, follow-up summaries, and uncertainty measures are not reported in the registry record. The absence of those results means the outcomes cannot be evaluated quantitatively from the record. It does not establish that the outcomes were not measured.
For safety, the record lists 20 participants at risk for serious adverse events and 8 affected, and 20 at risk for other adverse events and 20 affected. It also lists selected serious adverse-event terms and percentages. These figures describe reported safety categories, but they do not provide a complete account of event timing, recurrence, severity grading, attribution to treatment, or individual participant histories. The list includes terms referring to death; an aggregate death count is not reported in the registry record.
General: An estimate is more informative when accompanied by an uncertainty interval, because the interval conveys how much statistical uncertainty remains around the estimate under the analysis assumptions. No primary response estimate or confidence interval is reported. Likewise, a significance test cannot substitute for an effect estimate and its precision. The record lists zero analyses and gives no inferential result for the primary endpoint. No conclusion about statistical significance can be drawn from the available outcome information.
The single-group design also limits causal interpretation. Without a concurrent comparator, a response or survival outcome cannot establish what would have happened to comparable participants under a different treatment or no study treatment. This is a design limitation, not a result about sorafenib. The registry record also does not report why the trial was terminated, so termination should not be interpreted as evidence about benefit, lack of benefit, safety, or feasibility.
9. Statistical Methods Explained
The primary outcome is expressed as a participant count. For such an outcome, a complete statistical description would ordinarily identify the number meeting the response definition and the number included in the analysis. A proportion can then be estimated from those counts, with an uncertainty interval to show the precision of that estimate. The registry record reports neither the primary count nor an estimate and interval. No recalculated result can be derived from the recorded information.
What does a confidence interval add?
General: A confidence interval describes uncertainty around an estimate under a specified statistical model and analysis procedure. It is not a guarantee that the true value lies within a particular interval. For a response outcome, an interval would help readers judge whether the data are compatible with a broad range of response frequencies. Its width depends on the amount of information and the observed data. Since no primary response estimate or interval is reported in the registry record, the precision of the intended endpoint cannot be assessed from the recorded results.
Why does the analysis population matter?
The primary population is specified as participants who received at least one cycle. This definition determines who would contribute to the response count, but the record does not report the number treated or assessed. A complete account would explain how participants without an assessment were handled and whether the analysis used the originally specified population. The record does not report an intention-to-treat analysis, a per-protocol analysis, or another named analysis population. It is not possible to infer those choices from the stated endpoint population alone.
The measurement time is specified as 6 months after treatment. An endpoint at a defined time requires clear assessment rules, including how the time point was applied to participants who stopped treatment, progressed, or could not be assessed. The registry record describes the response categories and lesion measurability criteria, but does not report these missing-assessment procedures or clarify the primary responder threshold. It also does not report an analysis of response over time.
What can a single-group estimate establish?
General: A single-group study can describe outcomes observed among participants receiving the study treatment. It does not provide a direct estimate of the difference between treatment and a concurrent control. Changes in outcomes may reflect influences other than the intervention, including the course of illness, selection of participants, or differences in follow-up. Randomization is one way clinical trials seek to balance such influences between groups, but this study is not recorded as randomized and has no control group described. A within-group outcome should therefore not be treated as a comparative treatment effect.
The trial record lists no analysis details and no inferential analyses. It does not report a statistical model, a confidence-interval method, a test for the primary endpoint, or adjustments for covariates. These details are not reported in the registry record. General statistical explanations cannot fill in the analysis actually used.
How should planning calculations be read?
The sample-size assumptions describe a planning illustration rather than the trial's design. They specify a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation, with the effect to detect stated as a proportion of the observed effect. The record identifies this as an illustration computed from the observed effect, not as the trial's own planning justification. It does not report a protocol-based sample-size rationale. The assumptions of equal allocation between two arms do not describe the recorded single-group trial design, so any such illustration must not be read as the actual allocation or enrollment plan.
General: Sample-size calculations estimate the amount of information needed to detect a prespecified effect under stated assumptions. They are planning tools, not descriptions of what the trial observed. Power calculated for a hypothetical design is not observed power and does not show whether a trial result is true or clinically important. A planning illustration tied to an observed effect is especially dependent on that effect estimate and on the assumptions chosen. The primary response estimate needed to examine that basis is not reported in the registry record.
For time-to-event outcomes, analyses commonly account for the timing of events and participants whose event has not occurred by the end of observation. The registry defines the origins for progression-free and overall survival, but does not report event counts, censoring information, estimates, or analysis methods. Those outcomes cannot be reconstructed from their definitions alone.
Finally, the adverse-event summaries are counts and percentages, not an inferential comparison. There is no comparator group in the recorded design, and the registry does not report a treatment-attribution method or a statistical analysis of safety. General: Over-dispersion can matter when variability in count data exceeds what a simple probability model assumes; an analysis may then need a model that allows for that extra variability. No such count model or over-dispersion assessment is reported, and the primary endpoint is not presented with data that would permit a model assessment.
10. Multiplicity, Missing Data and Analysis Populations
The registry record lists a primary response outcome and secondary outcomes for progression-free survival, overall survival, and adverse events. It does not report how multiple outcomes were handled in statistical testing, whether any hierarchy among endpoints was prespecified, or whether any adjustment for multiple comparisons was planned. Multiplicity procedures are not reported in the registry record.
The record lists zero analyses, but that entry should not be interpreted as proof that no statistical work was done. Rather, it means no analysis is recorded in the information summarized. The statistical analysis plan, any interim analyses, subgroup analyses, and the timing of any analysis decisions are not reported in the registry record. The reason for termination is also not reported, and no inference about its relationship to outcome results is warranted.
Missing-data handling is not described. The record does not state how participants who did not receive a cycle, missed the 6-month assessment, discontinued treatment, or lacked a measurable lesion were treated in the primary analysis. It also does not report a missingness count or sensitivity analysis. These absences matter because the primary endpoint is defined for participants who received at least one cycle, while enrollment is reported separately.
The primary endpoint population is described, but no broader analysis-population rule is reported. There is no stated intention-to-treat population, per-protocol population, or rule for exclusions. The number who received at least one cycle and the number assessed are not reported in the registry record. As a result, the relationship between enrollment, treatment exposure, and endpoint analysis cannot be evaluated.
General: Multiplicity can increase the chance of a false positive when several hypotheses are tested without an appropriate strategy. Missing observations can also affect interpretation, particularly if the likelihood of missingness is related to outcome or treatment discontinuation. These are general methodological concerns, not evidence that either problem occurred in this trial. The record does not provide enough detail to assess how they were addressed.
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 |
|---|---|---|---|
| BAY 43-9006 | 8 | 20 | 40.0% |
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 |
|---|---|
| BAY 43-9006 | 20 of 20 |
Most frequent serious adverse event terms
| Event term | Organ system | BAY 43-9006 |
|---|---|---|
| Death not associated with CTCAE term - Disease progression NOS(not otherwise specified) | General disorders | 3 of 20 |
| Dyspnea (shortness of breath) | Respiratory, thoracic and mediastinal disorders | 2 of 20 |
| Death not associated with CTCAE term - Death NOS(not otherwise specified) | General disorders | 1 of 20 |
| Death not associated with CTCAE term - Sudden death | General disorders | 1 of 20 |
| Edema: limb | Blood and lymphatic system disorders | 1 of 20 |
| Ileus, GI (functional obstruction of bowel, i.e., neuroconstipation) | Gastrointestinal disorders | 1 of 20 |
| Infection with unknown ANC(Absolute neutrophil count) - Lung (pneumonia) | Infections and infestations | 1 of 20 |
| Lymphopenia | Blood and lymphatic system disorders | 1 of 20 |
| Pain - Abdomen NOS(not otherwise specified) | Gastrointestinal disorders | 1 of 20 |
| Pain - Eye | Eye disorders | 1 of 20 |
Most frequent non-serious adverse event terms
| Event term | Organ system | BAY 43-9006 |
|---|---|---|
| Lymphopenia | Blood and lymphatic system disorders | 16 of 20 |
| Fatigue (asthenia, lethargy, malaise) | General disorders | 14 of 20 |
| Hemoglobin | Blood and lymphatic system disorders | 14 of 20 |
| Sodium, serum-low (hyponatremia) | Metabolism and nutrition disorders | 11 of 20 |
| Glucose, serum-high (hyperglycemia) | Metabolism and nutrition disorders | 10 of 20 |
| Rash/desquamation | Skin and subcutaneous tissue disorders | 10 of 20 |
| Cough | Respiratory, thoracic and mediastinal disorders | 9 of 20 |
| Diarrhea | Gastrointestinal disorders | 9 of 20 |
| Weight loss | Investigations | 9 of 20 |
| Albumin, serum-low (hypoalbuminemia) | Metabolism and nutrition disorders | 8 of 20 |
Serious events with the highest arm-level rate: death not associated with ctcae term - disease progression nos(not otherwise specified) (15.0%), dyspnea (shortness of breath) (10.0%), death not associated with ctcae term - death nos(not otherwise specified) (5.0%), death not associated with ctcae term - sudden death (5.0%), edema: limb (5.0%).
The registry lists 20 participants at risk for serious adverse events, with 8 affected. For other adverse events, it lists 20 at risk and 20 affected. These are the posted participant counts for the two safety groupings. They do not describe the number of individual events, since a participant may experience more than one event. The record does not provide detailed event-level data or explain how repeat events were counted.
Selected serious adverse-event terms are listed with percentages: death not associated with a CTCAE term due to disease progression NOS at 15.0%, dyspnea at 10.0%, and death not associated with a CTCAE term, death NOS, sudden death, limb edema, and ileus, GI, each at 5.0%. The registry record does not report the term-specific denominators or make clear whether these percentages refer to participants or events. They should therefore be read as registry-listed percentages, not recalculated incidence estimates.
The term list includes categories referring to death, but the aggregate number of deaths is not reported in the registry record. Nor does the list establish whether an event was caused by sorafenib. Attribution, event timing, duration, management, and severity grading are not fully described in the recorded information. The counts characterize the reported safety summary; they do not, by themselves, establish a causal relationship or permit comparison with another treatment.
12. What the Result Does, and Does Not, Mean
The registry record establishes that a phase II, single-group trial evaluated sorafenib tosylate in advanced anaplastic thyroid cancer and designated response at 6 months after treatment as its primary endpoint. It also records enrollment of 20 participants, the treatment schedule, secondary outcome definitions, and summary adverse-event counts. These details describe the study's question and the available safety summary.
The record does not report the primary response count or estimate, so it does not establish the observed response frequency. It also does not provide numerical progression-free or overall survival results. No confidence interval or inferential result for the primary endpoint is recorded. Consequently, the posted information does not allow an assessment of the magnitude or statistical precision of the primary outcome.
A single-group outcome is not a comparison. Even if a response count were available, it would describe participants in this study and would not show how outcomes would differ under another treatment or a control condition. The study design does not support a randomized between-group treatment-effect estimate. The registry record also does not provide a reason for termination, so the terminated status cannot be used as a result about treatment efficacy or safety.
General: Statistical evidence and clinical importance are distinct questions. An estimate's uncertainty concerns how precisely an outcome has been measured under an analysis; clinical importance requires interpretation in the clinical context. The registry record lacks the primary numerical result needed even to assess its statistical precision. No claim about clinical benefit, lack of benefit, or equivalence follows from the absence of a reported result.
The adverse-event counts indicate that events were recorded among the participants at risk, and the listed serious terms include events concerning disease progression, dyspnea, deaths, limb edema, and ileus. They do not identify causation or provide a controlled comparison. The most defensible reading is descriptive: the registry records these safety counts and terms, while important details about event definitions, attribution, and the total number of deaths are not reported in the registry record.
13. Why This Trial Matters Statistically
This trial is statistically notable for the contrast between its stated clinical question and the limits of its recorded results. It was a phase II, single-group study with enrollment of 20 participants, and its primary endpoint was a response count at 6 months after treatment. Yet the registry record does not report that count, the number assessed, or an estimate with an uncertainty interval. Readers can identify the intended endpoint, but cannot quantify its result from the record.
The design also illustrates why an outcome measured within a treated group is not the same as a comparative treatment effect. Without a concurrent control group, differences from an external expectation cannot be attributed to treatment using the trial alone. This remains true regardless of whether an outcome is binary, as for response, or time-to-event, as for progression-free and overall survival.
Another important statistical issue is the distinction between enrollment and the primary analysis population. The record lists 20 enrolled participants but defines the primary population as those who received at least one cycle. It does not state the number who received treatment or were assessed. Without those denominators, readers cannot assess whether the endpoint count would reflect the full enrolled group or a subset.
The record's planning assumptions also illustrate why hypothetical calculations should not be confused with a trial's actual design. They describe a two-arm planning illustration, while the recorded study is single-group. Such an illustration is not evidence about the trial's enrollment rationale, observed power, or comparative result. The statistical design, analysis plan, and reason for termination are not reported in the registry record. These gaps limit reproducibility and interpretation without implying anything about the trial's unreported findings.
14. Limitations
- The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
- Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.
The main trial-specific limitation is the absence of a concurrent comparator. The study is recorded as single-group, with allocation not applicable and no masking. Outcomes among participants receiving sorafenib can be described, but the design does not provide a like-for-like control comparison. Causal interpretation is consequently limited.
The registry lists 20 participants enrolled, but the number who received at least one cycle is not reported. That matters because the primary endpoint population is defined by treatment receipt. The number assessed at 6 months and the number with a response are also not reported. The primary result therefore cannot be checked against the enrolled or treated population, and its precision cannot be evaluated.
The response definition is incomplete for interpreting a responder count. The record lists complete response, stable disease, partial response, and progressive disease, but does not clearly state which categories qualified as a response for the primary endpoint. It describes lesion measurement criteria, yet does not report the rules for missing or unevaluable assessments.
The status is terminated, but the reason is not reported in the registry record. Termination alone cannot establish whether the study stopped for safety, efficacy, recruitment, operational, or other reasons. The record also does not report numerical results for the secondary survival outcomes, analysis methods, multiplicity handling, interim analyses, or missing-data procedures.
Finally, the adverse-event summary provides counts and selected terms, but not sufficient detail to assess attribution, timing, recurrence, or term-specific denominators. The record lists terms related to death but does not report an aggregate death count. These reporting limitations restrict interpretation of both effectiveness and safety; they do not justify conclusions about unreported results.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Sorafenib in Treating Patients With Advanced Anaplastic Thyroid Cancer — NCT00126568.
- Registry record last updated 2018-01-19; status last verified 2017-12.
- Results first posted 2012-08-10.
- 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 NCT00126568, a phase II trial of sorafenib tosylate in advanced anaplastic thyroid cancer. It was a single-group study with no masking, and enrollment was 20. Oral treatment was scheduled twice daily on days 1-28, with courses repeating every 28 days unless disease progression or unacceptable toxicity occurred.
The primary outcome was the number of patients with response by RECIST criteria at 6 months after treatment, among participants receiving at least one cycle. The registry record does not report the response count or a numerical estimate. Progression-free survival, overall survival, and adverse events were listed as secondary outcomes, but numerical survival results are not reported.
The record lists 8 of 20 participants affected by serious adverse events and 20 of 20 affected by other adverse events, alongside selected serious-event terms. The study status is terminated; the reason is not reported in the registry record. Analysis details, missing-data procedures, and the primary outcome result are also not reported.