Trivalent Ganglioside Vaccine With Immunological Adjuvant or Immunological Adjuvant Alone in Metastatic Sarcoma Patients Who Are Rendered Disease Free: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Trivalent Ganglioside Vaccine With Immunological Adjuvant or Immunological Adjuvant Alone in Metastatic Sarcoma Patients Who Are Rendered Disease Free (NCT01141491), a randomized phase 2 study. The primary outcome is Progression Free Survival.

2. Clinical Question

Statistically, the question is whether the observed time-to-event experience differs between the randomized arms. The posted results give a median progression-free survival for each arm, with a 95% confidence interval. They do not give a hazard ratio, a p-value, or another reported comparative estimate. The medians alone describe each arm; they do not establish the size or precision of a treatment contrast.

3. Trial Design

The registry describes a randomized, multicenter, double-blind, phase II trial with a parallel-group model and quadruple masking. Participants were assigned to vaccine plus OPT-821 or OPT-821 alone. Each arm had 68 participants in the posted outcome results, and total enrollment was 136. The record lists the trial as completed.

The study population was metastatic sarcoma patients rendered disease free. This is a particular clinical setting: the endpoint concerns time until a later recurrence or another progression event, rather than change in a measurable tumor burden at enrollment. The registry says CT scans were used to evaluate recurrence, with progression determined by the principal investigator at each study site.

The intervention arm is described as receiving a KLH-conjugated trivalent ganglioside vaccine containing GM2, GD2 lactone, and GD3 lactone with OPT-821. The comparator arm received OPT-821 alone. The arm description gives injection schedules for the comparator, but a corresponding detailed schedule for the vaccine arm is not reported in the registry record. The record identifies masking as quadruple but does not explain which groups or roles were masked.

The primary endpoint is progression-free survival, with the registry stating a 3-years timeframe and reporting the endpoint in days. Overall survival is listed as a secondary outcome, but a result for that outcome is not reported in the registry record. The record does not report a detailed statistical analysis plan, the method used to compare the arms, or the approach to handling participants who did not complete follow-up.

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

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.

Population: Adults (male or female), 16 years of age and older who have metastatic sarcoma at initial presentation or who had relapsed disease and are rendered disease-free following surgical metastectomy

6. Primary Endpoint

The registry lists the primary outcome as Progression Free Survival, measured over 3-years.

Progression-free survival measures the time from randomization until a defined progression event or death. In this trial, the registry defines progression as evidence of tumor growth or appearance anywhere in the body, assessed by the site principal investigator. It also describes CT scans as the means of evaluating recurrence. The definition initially includes death from any cause; a later sentence refers to progression or death from disease. This wording makes the exact death component less clear than the recurrence component.

Time-to-event endpoints are used when the timing of an event matters and participants may have different lengths of observation. Such analyses can account for participants whose event has not been observed by the time their follow-up ends, provided the analysis method and censoring information are available. The registry record does not report those analysis details.

The posted primary results are medians in days, with 95% confidence intervals. A median is the point in the estimated event-time distribution by which half of the observed time-to-event experience lies on either side, subject to the survival-analysis estimation method. It gives a time-based summary, but does not describe the full pattern of events or the relative event rate over follow-up. The record states a 3-years timeframe, but the posted medians and intervals do not by themselves show the follow-up distribution or the number of events.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

Time-to-event analysis is designed for outcomes measured as elapsed time until an event, such as progression or death. Unlike a simple comparison of event counts, it uses both whether an event occurred and when it occurred. Participants who have not had an event by the end of their observed follow-up may contribute information up to that point without being treated as though an event occurred. This is commonly described as censoring. That explanation is general; the registry record does not report the censoring rules, follow-up completeness, or how censoring was handled in this trial.

What does a median summarize?

A median progression-free survival is a time point on the estimated event-time distribution. It is useful as an interpretable summary of when events accumulate, but it compresses the survival experience into a single value. It does not show whether the groups differed early or late in follow-up, whether their survival patterns crossed, or how many participants remained under observation at different times. The registry reports medians of 186.0 days and 271.0 days, but not the underlying survival curves or numbers at risk.

Median-based summaries can be difficult to interpret when the event-time distribution is not well characterized or when follow-up is limited. The confidence interval gives information about uncertainty in the median estimate, but not about every feature of the curve. The record labels the endpoint timeframe as 3-years and gives 95% confidence intervals, without describing the estimation procedure used for either the medians or their intervals.

What would a comparative analysis add?

A direct arm comparison might be reported using a hazard ratio, a test of the survival curves, or another prespecified method. In general, a hazard ratio compares the instantaneous event rates between groups over follow-up, subject to assumptions about how that relationship behaves. A hazard ratio is not the same as a ratio of medians, and it does not tell a reader the absolute probability of remaining progression free at a particular time. A confidence interval for a comparative estimate would show its statistical precision. No hazard ratio, comparative p-value, or other such result is reported in the registry record.

Methods such as a log-rank test and a Cox proportional-hazards model are commonly used in time-to-event settings. These are general examples, not methods that can be attributed to this trial: the registry record does not report which test or model was used. If proportional hazards are assumed for a model, that assumption concerns whether the relative event rate is sufficiently stable over time. The record does not report an assessment of that assumption. Nor does it report any adjustment variables or a prespecified analysis population.

How should confidence intervals be read?

A confidence interval communicates uncertainty associated with an estimate under a statistical procedure. The 95% confidence intervals reported for the arm-specific medians are 163.0 to 193.0 days and 186.0 to 273.0 days. They are intervals for the respective median estimates, not intervals for an arm difference. Comparing intervals by eye is not a substitute for a formal test or a confidence interval for the contrast. The registry record does not provide a comparative interval or the method used to derive the arm-specific intervals.

Uncertainty can arise from the number and timing of events, the amount of follow-up, and the pattern of censoring. These are general considerations. The record does not report the event count for progression-free survival, the number of participants censored, or follow-up summaries, so the contribution of these factors cannot be assessed from the posted results.

What do planning calculations represent?

Sample-size planning asks how many participants or events might be needed under stated assumptions to detect a specified effect with a chosen error rate and power. It is a design exercise, not a measure of what the completed trial actually achieved. The registry describes planning illustrations using a two-sided significance level of 0.05, equal allocation between arms, and a normal approximation, with the target effect defined as a fraction of the observed effect. For time-to-event calculations, the stated convention is a total event count. The record also marks the two-arm comparison values for this median-time endpoint as missing or not estimable.

Those planning assumptions are not reported as the trial’s original design justification. The registry does not report a prospective sample-size calculation, the effect size assumed at design, or the planned power. Any planning illustration based on the observed effect is retrospective and should not be described as observed power. Because the comparison values are not estimable in this record, there is no numerical planning result to interpret for this endpoint.

In general, analysis choices should be interpreted alongside the protocol and statistical analysis plan, including endpoint definitions, censoring rules, model assumptions, and handling of missing observations. Those details are not reported in the registry record. The posted medians and intervals can be described, but they do not reveal which inferential method generated the estimates or whether the analysis followed a prespecified plan.

10. Multiplicity, Missing Data and Analysis Populations

The registry record lists progression-free survival as the primary outcome and overall survival as a secondary outcome. It does not report a multiplicity strategy for controlling the chance of false-positive findings across outcomes, time points, or analyses. A multiplicity approach is relevant when several statistical tests are planned, because interpreting each test separately can overstate the strength of evidence. This is a general statistical consideration; the record does not establish how many analyses were planned.

The record reports no analysis entries and does not provide a detailed statistical analysis plan. It does not state whether the primary analysis used an intention-to-treat population, a per-protocol population, or another analysis set. It also does not report exclusions after randomization or the number of participants included in each endpoint analysis. Although each arm has 68 participants in the posted results, that does not by itself establish the analysis population or completeness of follow-up.

Missing-data procedures, reasons for missing assessments, and censoring rules are not reported in the registry record. For a time-to-event endpoint, incomplete follow-up is often handled through censoring, but the validity of that approach depends on assumptions and on the actual follow-up process. The record does not give enough information to evaluate those issues. Overall survival is listed as a secondary outcome, but its result is not reported. Accordingly, neither missing-data handling nor multiplicity can be assessed from the posted results.

11. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 0% reporting threshold.

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: erythema (1.5%), anaemia (1.5%), catheter site cellulitis (1.5%), cerebrovascular accident (1.5%), anaphylactoid reaction (1.5%).

The registry reports serious adverse events affecting 4 of 68 participants in the vaccine plus OPT-821 arm and 8 of 68 participants in the OPT-821-alone arm. Other adverse events were reported for 1 of 68 participants in the vaccine-plus-adjuvant arm and 0 of 68 in the adjuvant-alone arm. These counts should be read as the registry’s posted summaries, not as a complete estimate of all safety risks.

The serious adverse event terms listed are erythema, anaemia, catheter site cellulitis, cerebrovascular accident, anaphylactoid reaction, and hip fracture, each with a reported frequency of 1.5%. The registry does not identify the arm for each term in the posted term list, nor does it report event-level detail, timing, duration, seriousness criteria, or attribution to study treatment. Death counts are not reported in the registry record.

Counts alone do not establish whether a treatment caused an event or whether the arms differ in safety. Interpretation also depends on how events were collected, the number of participants observed for safety, follow-up duration, and definitions used. These details are not reported in the registry record. The figures should therefore be treated as descriptive safety information, not as a causal comparison.

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

The registry results show arm-specific median progression-free survival estimates: 186.0 days for vaccine plus OPT-821 and 271.0 days for OPT-821 alone. Each estimate has a 95% confidence interval. These figures summarize the posted time-to-event data, but the registry does not provide a comparative hazard ratio, p-value, or confidence interval for the difference between arms. They cannot establish the size or statistical precision of a treatment contrast on their own.

The trial’s endpoint reflects time until a recurrence or other progression event, with death included in the registry’s initial definition. The record describes CT-based assessment and investigator determination. It does not report event counts, censoring, or follow-up details that would help readers assess the completeness and stability of the estimates. The later wording about death from disease also leaves some ambiguity in the endpoint description.

The safety summaries report serious adverse events for 4 participants in the vaccine-plus-adjuvant arm and 8 in the adjuvant-alone arm. They do not establish that the intervention caused or prevented any event. The registry gives no deaths count and limited detail about the listed serious adverse event terms.

Overall survival is named as a secondary outcome, but no result is reported. The record also does not report the trial’s sample-size justification, detailed statistical plan, or analysis populations. These omissions limit assessment of the planned comparisons, missing information, and robustness of the findings. The results are therefore best understood as descriptive registry summaries, not as a complete account of the trial’s inferential findings.

13. Why This Trial Matters Statistically

This trial raises a useful statistical distinction between an arm-specific summary and a comparative result. A median progression-free survival can be clinically interpretable as a time point, but a comparison between arms requires an estimate of the contrast and its uncertainty. The registry presents medians and confidence intervals for each group, while omitting a reported hazard ratio, p-value, or other formal comparison. Readers can identify the posted values without being able to assess the precision of an arm-to-arm effect.

The distinction matters especially for time-to-event outcomes. Participants may have different follow-up durations, and the timing of events contributes information beyond a simple count. Without event totals, numbers at risk, follow-up summaries, or censoring details, readers cannot see how much information supports the medians or how the observed patterns evolved over time. These are general considerations that apply to survival analysis; the relevant trial details are not reported in the registry record.

The record also illustrates why endpoint definitions and analysis plans matter. It defines progression using investigator assessment and CT scans, while its wording about death is not entirely consistent. The registry does not provide a detailed statistical plan, multiplicity strategy, or analysis populations. Those omissions make it harder to evaluate whether the posted results correspond to a prespecified analysis and how secondary outcomes were handled.

Finally, the serious adverse event counts are descriptive and do not, by themselves, establish causality or a comparative safety effect. Taken together, the record offers useful basic information about the randomized comparison and its posted outcome summaries, while leaving important elements of inferential and safety interpretation unreported.

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 registry record provides median progression-free survival estimates and confidence intervals but no comparative effect estimate or inferential test. It does not report a hazard ratio, p-value, survival curves, event totals, or numbers at risk. That limits assessment of the time pattern and precision of any difference between arms.

The endpoint description includes investigator-determined progression and CT-based recurrence assessment. It first includes death from any cause, then refers to death from disease. The record does not clarify this wording difference or provide detailed criteria for adjudicating events. The method used to estimate the medians and confidence intervals is also not reported.

The registry lists overall survival as a secondary outcome without a posted result. It does not report a statistical analysis plan, multiplicity procedure, analysis populations, missing-data approach, censoring rules, or follow-up completeness. The arm sizes in the posted results do not establish how many participants contributed to each endpoint analysis.

Safety reporting is limited to participant counts and a list of serious adverse event terms with frequencies. The term list is not assigned to arms in the record, and death counts, event timing, attribution, and further clinical detail are not reported. These limitations mean the available safety figures should not be interpreted as a causal treatment comparison.

The registry also does not report the trial’s original sample-size justification or prospective power assumptions. Planning calculations based on the observed effect are not a substitute for that information, and the two-arm planning values for this endpoint are marked missing or not estimable. These gaps restrict what can be concluded from the registry record alone.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Trivalent Ganglioside Vaccine With Immunological Adjuvant or Immunological Adjuvant Alone in Metastatic Sarcoma Patients Who Are Rendered Disease Free — NCT01141491.
• Registry record last updated 2017-04-12; status last verified 2016-12.
• Results first posted 2016-12-07.
• Data retrieved from ClinicalTrials.gov on 2026-11-09.
• Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.

18. Record Summary

This completed randomized, multicenter, double-blind, phase II trial enrolled 136 metastatic sarcoma patients rendered disease free. It compared a trivalent ganglioside vaccine plus OPT-821 with OPT-821 alone, with 68 participants in each arm in the posted results. The listed primary outcome was progression-free survival over a 3-years timeframe.

The reported median progression-free survival was 186.0 days with vaccine plus OPT-821 and 271.0 days with OPT-821 alone. The registry gives a 95% confidence interval for each median but no comparative hazard ratio or p-value. Overall survival is listed as a secondary outcome, without a reported result. Serious adverse events affected 4 participants in the vaccine-plus-adjuvant arm and 8 in the adjuvant-alone arm. Important analysis and follow-up details are not reported in the registry record.