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 Safety and Efficacy Study of PLX3397 in Adults With Relapsed or Refractory Hodgkin Lymphoma (NCT01217229), a na phase 2 study. The primary outcome is Progression-Free Survival According to the Cheson Criteria by Kaplan-Meier Analysis Following Orally Administered PLX3397 in Adults With Relapsed or Refractory Hodgkin Lymphoma (Modified Intent-to-Treat Population).
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01217229 |
| Phase | Phase 2 |
| Condition | Hodgkin Lymphoma |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 20 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Daiichi Sankyo |
| Results posted | Yes |
2. Clinical Question
The study examined PLX3397 in adults with relapsed or refractory classical Hodgkin lymphoma. The registry record describes the study as a Phase 2 safety and efficacy study, with overall response rate identified as the primary objective in the brief summary. However, the primary outcome measure listed in the record is progression-free survival (PFS) by Kaplan-Meier analysis. The record does not reconcile these descriptions, and it does not report a PFS median or inter-quartile range.
Population
Adults with relapsed or refractory Hodgkin lymphoma. The brief summary specifies classical Hodgkin lymphoma. The PFS population is described as the Modified Intent-to-Treat population, whose definition is not reported in the registry record.
Intervention
Orally administered PLX3397, described in the brief summary as a selective inhibitor of Fms, Kit, and oncogenic Flt3 activity.
Comparator
No comparator group is listed. The study is identified as single-group, and allocation is recorded as not applicable.
Primary question
The listed primary outcome asks how long participants remained alive without documented disease progression, measured from the first day of treatment to progression or death. The record also identifies overall response rate as the primary objective in its brief summary, so the relationship between these descriptions is unclear.
Because the record describes a single-group study without a listed control, its results can describe outcomes observed during PLX3397 treatment but cannot provide a direct randomized comparison with another treatment. The posted primary outcome is time-to-event, not a simple count of responses. Its interpretation would depend on the estimated event-time distribution and the completeness of follow-up, alongside the population and analysis methods. Those details are not all reported in the registry record.
3. Trial Design
This is a completed Phase 2 study sponsored by Daiichi Sankyo. The registry describes a single-group study of PLX3397 in adults with relapsed or refractory Hodgkin lymphoma. Enrollment is listed as 20. The intervention is an orally administered drug; no control intervention or separate comparator arm is listed.
Allocation is recorded as not applicable, and masking is recorded as none. These design features mean the study is not described as a randomized, masked comparison. Consequently, the posted data do not establish a between-group treatment contrast. Outcomes can be described for the study group, but changes over time or comparisons with outcomes from other settings would not by themselves isolate a treatment effect.
The study began on 2011-03-03, reached primary completion on 2012-04-26, and is recorded as completed. The primary outcome measure listed in the record is PFS assessed by Kaplan-Meier analysis, with a timeframe of baseline to 1 year postdose. The description defines the event as documented disease progression or death, whichever occurred first, and measures time from the first day of treatment. PFS was assessed in the Modified Intent-to-Treat population, but the record does not define that population.
The brief summary describes overall response rate as the primary objective and names safety, duration of response, disease control rate, PFS, and effects of the drug on the body as secondary objectives. In contrast, the listed primary outcome measure is PFS. The registry record does not explain the difference between the objective described in the summary and the named primary outcome measure.
Enrollment, study dates, phase, and design describe the planned and registered study context; they do not supply the missing outcome estimate. The registry record does not report the median PFS, its inter-quartile range, a confidence interval, or a sponsor-reported hazard ratio. It also does not report a comparator-based analysis. These omissions limit how precisely the observed PFS can be characterized from the posted 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 | PLX3397 |
|---|---|
| STARTED | 20 |
| COMPLETED | 0 |
| NOT COMPLETED | 20 |
Reasons for not completing this period:
| Reason | PLX3397 |
|---|---|
| Adverse Event | 1 |
| Disease progression, deterioration | 2 |
| Disease progression, Cheson criteria | 14 |
| Protocol Violation | 1 |
| Disease progression not confirmed | 2 |
Analysis population for the primary outcome, as defined in the registry: Progression-free survival was assessed in the Modified Intent-to-Treat population.
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 | PLX3397 |
|---|---|---|
| Participants analysed | 20 | |
| Age, Categorical: <=18 years | Participants | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 17 |
| Age, Categorical: >=65 years | Participants | 3 |
| Age, Continuous | years | 40.9 (SD 19.05) |
| Sex: Female, Male: Female | Participants | 11 |
| Sex: Female, Male: Male | Participants | 9 |
| Region of Enrollment: United States | participants | 20 |
6. Primary Endpoint
The registry lists the primary outcome as Progression-Free Survival According to the Cheson Criteria by Kaplan-Meier Analysis Following Orally Administered PLX3397 in Adults With Relapsed or Refractory Hodgkin Lymphoma (Modified Intent-to-Treat Population), measured over Baseline to 1 year postdose.
| Element | Registry entry |
|---|---|
| Result type | Median |
| Measure of spread | Inter-Quartile Range |
| Unit | days |
| Endpoint classification | Time-to-Event Analysis |
PFS is a time-to-event endpoint. In this study, it is defined as the number of days from the first day of treatment until the first documented disease progression or death, whichever occurred first. A participant who experiences either event reaches the endpoint at that time. The registry specifies Kaplan-Meier analysis and a timeframe of baseline to 1 year postdose.
Time-to-event measures are useful when the timing of an event matters and participants may have different lengths of observation. Kaplan-Meier methods can incorporate information from participants whose event has not been observed by the end of their available follow-up, provided their follow-up and censoring are handled appropriately. This is a general description of the method; the registry record does not report the censoring rules or the number of participants censored.
The median PFS is the time by which the estimated event-free proportion has reached the midpoint of its range. The inter-quartile range describes the spread of event times around the middle of the distribution. These summaries can make a time-to-event result more interpretable than a single event count, but they do not show the full curve or explain the precision of the estimate on their own.
The record names the median and inter-quartile range as the outcome summary, but the corresponding values are not reported in the registry record. A confidence interval and the underlying event count are also not reported. Therefore, the endpoint's definition is available, but its posted numerical result and precision cannot be assessed.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies PFS as the primary outcome measure and describes its definition and analysis method. It does not report a median PFS, an inter-quartile range, or a confidence interval. As a result, the posted record does not allow a reader to assess the estimated duration of PFS or how precise that estimate is. The outcome definition alone is not a result.
There is also a difference in emphasis within the record. Its brief summary calls overall response rate the primary objective, while the listed primary outcome measure is PFS. The summary names several secondary objectives, including safety and other disease outcomes. The record does not explain whether the outcome listing reflects a change in the study objectives, how the outcomes were ranked, or which analysis was intended to be primary in the final report. The distinction matters because a study's stated question and its reported endpoint need to be interpreted together.
The design is single-group, with allocation recorded as not applicable and masking recorded as none. There is no listed control group for a direct comparison. Thus, even if a numerical outcome estimate were available, the design would support a description of outcomes in the treated study group rather than a randomized estimate of how outcomes differ from an alternative. Other factors affecting participants' outcomes cannot be separated from treatment effects through a concurrent randomized contrast in this record.
The enrollment is listed as 20, and the PFS population is called Modified Intent-to-Treat. The record does not define that population or report the number included in the PFS analysis. It does not provide the number of progression or death events, the number censored, follow-up completeness, or details of missing-data handling. These omissions prevent assessment of how much information contributed to the time-to-event estimate.
No sponsor-reported hazard ratio is present in the registry record, and no comparator is listed. A hazard ratio would ordinarily describe a relative event rate over follow-up for a specified comparison; without a comparison group, it would not be a substitute for a single-group median. No confidence interval is available to characterize statistical precision. The record also does not report a statistical analysis plan, a multiplicity strategy, or an explanation of the relationship between the listed primary objective and primary outcome measure.
The serious adverse event listing records 1 affected among 20 at risk, with 0 deaths. Lung infection and pyrexia are each listed among the top serious event terms at 5.0%. These are registry safety figures, not a comparison against another group. The other adverse-event listing records 20 affected among 20 at risk, but the record's available summaries do not provide event-level detail or clarify overlap across terms. The safety information should therefore be read as descriptive reporting, not as a comparative estimate.
Overall, the record offers useful context on the study population, design, endpoint definition, and selected safety figures, but it does not provide the primary numerical efficacy result. Interpretation of efficacy or precision beyond those details is not supported by the posted record.
9. Statistical Methods Explained
The listed primary outcome uses Kaplan-Meier analysis, a standard approach for time-to-event data. General explanation: rather than treating all participants as if they had the same observation period, the method estimates the event-free experience over time using each participant's observed follow-up. A participant contributes information until the event occurs or until follow-up ends without an observed event. The latter situation is generally called censoring. The registry record does not report how censoring was defined or how many participants were censored.
What does the endpoint count?
The event is the first documented disease progression or death, whichever occurs first. The time origin is the first day of treatment, and the stated unit is days. This definition combines progression and death into a single endpoint: it does not separately estimate time to progression and time to death. The timeframe is listed as baseline to 1 year postdose. The registry record does not provide a numerical summary of the observed time-to-event distribution.
What does a median represent?
General explanation: the Kaplan-Meier median is the time at which the estimated proportion remaining free of the event reaches the midpoint. It is a summary of the estimated event-time distribution, not the average follow-up time and not a statement that every participant has had an event by that time. If the estimated curve does not reach that midpoint during observation, a median may not be estimable; the registry record does not state whether that occurred in this study.
The outcome specification names the median and inter-quartile range. General explanation: the inter-quartile range describes the range between the lower and upper quartiles of the distribution, giving information about the spread of event times around its center. Neither the median nor the inter-quartile range is reported in the registry record, so their values cannot be interpreted. A confidence interval is also not reported. In general, a confidence interval conveys uncertainty around an estimated quantity; without one, the precision of a reported estimate cannot be evaluated in that way.
Why does a single-group design matter?
General explanation: a control group can provide a concurrent reference for separating outcomes associated with an intervention from outcomes that might occur for other reasons. This study is described as single-group, with allocation recorded as not applicable and masking recorded as none. No comparator is listed. Accordingly, the registry record does not support a randomized between-group contrast, and a within-study outcome description should not be treated as a comparative treatment effect.
The brief summary describes PLX3397 as a selective inhibitor of Fms, Kit, and oncogenic Flt3 activity. That is the drug description in the record; it does not establish a statistical result. The intervention is listed as orally administered PLX3397. The record does not provide a separate dose or treatment schedule in the registry record for this analysis.
What can be learned from the population label?
The PFS population is named Modified Intent-to-Treat. General explanation: an analysis population label indicates which participants are intended to contribute to a particular analysis, but labels can be defined differently across studies. The registry record does not state the inclusion rules for this population or how it relates to enrollment. It also does not report the number analyzed for PFS, so the population label alone is insufficient to assess analysis completeness.
There are no sponsor-reported hazard ratios in the registry record. General explanation: a hazard ratio is a relative comparison of event rates over follow-up and depends on a specified contrast. With no comparator arm listed, a comparative hazard ratio is not presented. The record also does not describe an adjusted model, model assumptions, or a statistical analysis plan. No assumptions should be inferred from the endpoint name or study phase.
The record names overall response rate as the primary objective in its brief summary but lists PFS as the primary outcome measure. This distinction is important for statistical interpretation: an objective is a stated study aim, whereas an outcome measure identifies what is recorded and how it is summarized. The record does not explain whether this difference reflects distinct versions of the study description or another reason. It also does not state how the listed primary and secondary outcomes were prioritized in analysis.
General explanation: when a study evaluates multiple outcomes, multiplicity procedures may be used to control the chance of a misleading positive finding across tests. Whether such procedures are appropriate depends on the planned hypotheses and analysis. The registry record does not report a multiplicity adjustment or an analysis plan, so no conclusion about adjustment can be drawn. It likewise does not report interim-analysis procedures, missing-data methods, or the handling of participants with incomplete follow-up.
10. Multiplicity, Missing Data and Analysis Populations
The brief summary identifies overall response rate as the primary objective and lists safety, duration of response, disease control rate, PFS, and effects of the drug on the body among the secondary objectives. The separately listed primary outcome measure is PFS. The registry record does not explain the difference between the primary objective and the named primary measure, or specify how these outcomes were ordered for analysis.
A statistical plan for handling multiple outcomes or tests is not reported in the registry record. In general, multiplicity methods address the increased chance of a misleading finding when several hypotheses are assessed. Without a reported analysis plan, it is not possible to determine whether adjustment was intended or how any such procedure would apply. Interim analyses are also not reported.
The PFS population is described as Modified Intent-to-Treat, but its definition is not reported in the registry record. The record does not report the number included in the PFS analysis, the number of events, or the number censored. It does not describe how participants with missing assessments or incomplete follow-up were handled, whether imputation was used, or what assumptions were applied to censoring.
These omissions do not establish that data were missing or that an analysis was inappropriate. They mean that the posted information is not enough to evaluate the population definition, completeness of follow-up, or sensitivity of the result to missing information. The median PFS and inter-quartile range themselves are not reported in the registry record, further limiting assessment of the primary endpoint.
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 |
|---|---|---|---|
| PLX3397 | 1 | 20 | 5.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| PLX3397 | 0 of 20 |
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 |
|---|---|
| PLX3397 | 20 of 20 |
Most frequent serious adverse event terms
| Event term | Organ system | PLX3397 |
|---|---|---|
| Lung infection | Infections and infestations | 1 of 20 |
| Pyrexia | General disorders | 1 of 20 |
Most frequent non-serious adverse event terms
| Event term | Organ system | PLX3397 |
|---|---|---|
| Fatigue | General disorders | 8 of 20 |
| Hair depigmentation | Skin and subcutaneous tissue disorders | 8 of 20 |
| Fatigue | Gastrointestinal disorders | 8 of 20 |
| Hair colour changes | Skin and subcutaneous tissue disorders | 8 of 20 |
| Anaemia | Blood and lymphatic system disorders | 6 of 20 |
| Thrombocytopenia | Blood and lymphatic system disorders | 6 of 20 |
| Rash | Skin and subcutaneous tissue disorders | 5 of 20 |
| Dyspnea | Respiratory, thoracic and mediastinal disorders | 5 of 20 |
| Blood lactate dehydrogenase increased | Investigations | 5 of 20 |
| Dyspnoea | Respiratory, thoracic and mediastinal disorders | 5 of 20 |
Serious events with the highest arm-level rate: lung infection (5.0%), pyrexia (5.0%).
The registry lists safety figures for the PLX3397 group. It records 20 participants at risk for serious adverse events and 1 affected. It also lists 20 at risk for other adverse events and 20 affected. The record reports 0 deaths. These are descriptive figures; because no comparator group is listed, they do not estimate a difference in safety between treatments.
The top serious adverse event terms are lung infection and pyrexia, each listed at 5.0%. These percentages are reported as registry figures. The record does not provide event-level detail in the registry entries, such as timing, duration, severity grading beyond the serious classification, or whether a participant experienced more than one term. The terms and percentages should therefore be read as the listed summaries rather than as a complete account of each participant's course.
Serious adverse events and other adverse events are separate registry categories. Their affected counts should not be added together to infer a total number of participants, because the record does not state whether people appear in both categories. The serious-event listing also does not by itself show how often events were judged related to treatment. The registry record does not report such attribution information.
These figures describe what the registry records for this study group. They do not establish comparative safety, explain causation, or replace fuller clinical reporting.
12. What the Result Does, and Does Not, Mean
The posted information establishes the context of a completed Phase 2, single-group study of orally administered PLX3397 in adults with relapsed or refractory Hodgkin lymphoma. It identifies a PFS endpoint, defines progression or death as the event, names Kaplan-Meier analysis, and specifies the Modified Intent-to-Treat population. It also includes selected safety figures. These registry entries help a reader understand what was studied and how the primary outcome was intended to be described.
The record does not report the median PFS or inter-quartile range, despite naming them as the outcome summaries. It also does not report a confidence interval, event count, censoring count, or sponsor-reported hazard ratio. Consequently, the posted data do not show the numerical PFS result or its statistical precision. No efficacy conclusion can be drawn from the endpoint definition alone.
The study has no listed comparator group and is identified as single-group, with allocation not applicable and no masking. Its results therefore cannot provide a randomized estimate of how PLX3397 outcomes differ from outcomes under another treatment. A single-group description also cannot separate the intervention's contribution from other influences on outcomes.
The registry's brief summary names overall response rate as the primary objective, while the listed primary outcome measure is PFS. The record does not explain this difference. It also does not report how multiple outcomes were handled statistically or define the Modified Intent-to-Treat population. These gaps limit assessment of how the endpoint listing relates to the full analysis.
The serious adverse event figures and the listed event terms are descriptive. They do not establish comparative risks or event causation. The record's safety summaries should be interpreted within the information they report, without extrapolating beyond this study group.
In short, the registry record describes a study question and selected design and safety details, but it does not provide the primary numerical efficacy estimate needed to characterize the observed PFS result. It does not support claims about comparative benefit or harm.
13. Why This Trial Matters Statistically
This study illustrates why a clear endpoint definition is only part of statistical interpretation. The registry specifies the PFS event, time origin, unit, analysis method, timeframe, and named analysis population. Those details tell readers what the measure is intended to capture. Yet without the median, inter-quartile range, or confidence interval, the record does not reveal the estimated outcome or its precision.
It also illustrates the importance of distinguishing a study objective from a registered outcome measure. The brief summary identifies overall response rate as the primary objective, whereas the listed primary outcome measure is PFS. Both descriptions are part of the registry record, but their relationship is not explained. That uncertainty makes it harder to determine how the final reported endpoint aligns with the stated aims.
The single-group design is another central statistical consideration. A group can be described on its own, but without a concurrent comparator the study does not provide a randomized contrast. This distinction prevents descriptive outcome figures from being misread as proof of an intervention effect relative to another option.
Finally, the Modified Intent-to-Treat label and safety summaries show why definitions and denominators matter. The population label is not defined, and the record does not report the analyzed PFS population or follow-up details. Safety counts are informative as registry descriptions, but do not establish comparative risk or causation. Together, these features make the record a useful example of reading endpoint definitions, design, and reporting completeness as separate parts of the statistical evidence.
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 listed primary outcome's numerical summaries are not reported in the registry record. The median PFS and inter-quartile range are named, but their values are absent. A confidence interval is not reported either, so the precision of the estimate cannot be assessed from the posted information.
The record does not report the number of progression or death events, the number censored, follow-up completeness, or censoring rules. It specifies a timeframe of baseline to 1 year postdose, but does not provide details needed to assess how observation ended for participants who had no recorded event. These are important considerations for a Kaplan-Meier analysis.
The PFS analysis population is called Modified Intent-to-Treat, without a definition or reported analysis count. The record does not explain how missing assessments, incomplete follow-up, or other unavailable data were handled. It also does not report the statistical analysis plan, multiplicity procedures, or interim analyses.
The single-group design, with no listed comparator and no masking, limits interpretation to description of the study group rather than a randomized comparison. The record's brief summary names overall response rate as the primary objective, while the registered primary outcome measure is PFS; this difference is not explained. The available safety summaries also lack event-level detail and do not establish treatment attribution.
These limitations concern the information reported in the registry record. They do not show that particular methods were or were not used outside what the record reports.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Safety and Efficacy Study of PLX3397 in Adults With Relapsed or Refractory Hodgkin Lymphoma — NCT01217229.
- Registry record last updated 2020-06-30; status last verified 2020-06.
- Results first posted 2013-03-15.
- 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
NCT01217229 is a completed Phase 2, single-group study sponsored by Daiichi Sankyo. It enrolled 20 adults with relapsed or refractory Hodgkin lymphoma and evaluated orally administered PLX3397. Allocation is recorded as not applicable, and masking as none.
The listed primary outcome is PFS by Kaplan-Meier analysis, measured from the first day of treatment to documented progression or death. The PFS population is described as Modified Intent-to-Treat. The brief summary separately identifies overall response rate as the primary objective; the registry record does not explain the difference.
The record does not report the median PFS, inter-quartile range, or confidence interval. It lists 1 affected among 20 at risk for serious adverse events, 20 affected among 20 at risk for other adverse events, and 0 deaths. Lung infection and pyrexia are each listed among the top serious event terms at 5.0%.