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 A Study of Vismodegib (GDC-0449, Hedgehog Pathway Inhibitor) With Concurrent Chemotherapy and Bevacizumab As First-Line Therapy for Metastatic Colorectal Cancer (NCT00636610), a randomized phase 2 study. The primary outcome is Progression-free Survival (PFS).
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00636610 |
| Phase | Phase 2 |
| Condition | Metastatic Colorectal Cancer |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Double |
| Enrollment | 199 |
| Arms in the primary outcome | 2 |
| Lead sponsor | Genentech, Inc. |
| Results posted | Yes |
2. Clinical Question
Population
Patients with metastatic colorectal cancer receiving first-line treatment. The primary endpoint population was the intent-to-treat population, defined in the registry record as all randomized patients. The trial enrolled 199 participants.
Intervention
Vismodegib 150 mg, taken orally once daily starting on Day 3 of each 2-week treatment cycle, alongside bevacizumab and the chemotherapy regimen selected for the patient.
Comparator
Placebo to vismodegib, taken orally once daily starting on Day 3 of each 2-week treatment, alongside bevacizumab and the selected chemotherapy regimen. The chemotherapy option was Modified FOLFOX or FOLFIRI.
Primary question
How did median progression-free survival compare between the randomized vismodegib and placebo groups when each was added to chemotherapy and bevacizumab? Progression-free survival was measured from randomization to documented disease progression or death from any cause, whichever occurred first.
The study addressed whether adding a Hedgehog pathway inhibitor to first-line biochemotherapy was associated with a different time to progression or death than adding placebo. It was randomized, placebo-controlled, and double-blind. The physician and patient chose FOLFOX or FOLFIRI; randomization to vismodegib or placebo was stratified according to that chemotherapy choice and whether RECIST-measurable disease was present at baseline.
The reported primary endpoint is a time-to-event measure rather than a count of responses at a single assessment. It captures the time until the first of the specified events, while the median describes the point by which half of the relevant survival distribution has experienced an event. The registry record reports median values and 90% confidence intervals for both randomized groups. It does not report a hazard ratio or a sponsor-reported comparative analysis in the available record.
3. Trial Design
This was a randomized, placebo-controlled, double-blind, parallel-group phase II study of vismodegib with concurrent chemotherapy and bevacizumab as first-line therapy for metastatic colorectal cancer. The registry record gives an enrollment of 199 and status of completed. The recorded study start was 2008-05, and primary completion was 2010-12.
Patients were assigned to vismodegib 150 mg or placebo. Both groups also received bevacizumab and one of two chemotherapy regimens: Modified FOLFOX or FOLFIRI. The treating physician and patient decided which chemotherapy regimen to use. Randomization was stratified by the chosen regimen and the presence or absence of RECIST-measurable disease at baseline. Thus, chemotherapy choice was not itself the randomized comparison described in the record; the randomized contrast was vismodegib versus placebo within the treatment context.
The treatment descriptions state that study drug or placebo was taken orally once daily starting on Day 3 of each 2-week treatment cycle. The brief summary says treatment continued until disease progression. Beyond those details, the duration and modification rules for individual therapies are not reported in the registry record.
The primary endpoint population was intent-to-treat: all randomized patients. The reported arm sizes were 98 for vismodegib and 101 for placebo. The registry record describes progression-free survival from randomization to the earlier of documented disease progression or death from any cause. The endpoint timeframe is described as from first treatment through the data cut-off date of March 15, 2010, up to 90 weeks. The exact analysis procedures, including censoring rules and any model used for a comparative treatment estimate, are not reported in the registry record.
Serious adverse-event summaries are presented separately by chemotherapy regimen and randomized study drug. Those safety group counts should not be mistaken for the primary endpoint population counts: the record does not explain in detail how the safety analysis population was defined or why its group sizes differ from the overall randomized arm sizes.
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 | Vismodegib 150 mg | Placebo to Vismodegib |
|---|---|---|
| STARTED | 98 | 101 |
| COMPLETED | 6 | 18 |
| NOT COMPLETED | 92 | 83 |
Reasons for not completing this period:
| Reason | Vismodegib 150 mg | Placebo to Vismodegib |
|---|---|---|
| Adverse Event | 4 | 4 |
| Death | 6 | 3 |
| Physician decision to withdraw patient | 15 | 9 |
| Subject decision to withdraw | 15 | 11 |
| Disease progression - radiographic | 41 | 51 |
| Disease progression - clinical | 8 | 3 |
| Reason for discontinuation not available | 3 | 2 |
Analysis population for the primary outcome, as defined in the registry: Intent-to-treat patient population: All randomized patients.
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 | Vismodegib 150 mg | Placebo to Vismodegib | Total |
|---|---|---|---|---|
| Participants analysed | 98 | 101 | 199 | |
| Age, Continuous | years | 60.8 (SD 10.4) | 60.4 (SD 11.0) | 60.6 (SD 10.7) |
| Sex: Female, Male: Female | Participants | 39 | 46 | 85 |
| Sex: Female, Male: Male | Participants | 59 | 55 | 114 |
6. Primary Endpoint
The registry lists the primary outcome as Progression-free Survival (PFS), measured over From first treatment through the data cut-off date of March 15, 2010, up to 90 weeks.
| Element | Registry entry |
|---|---|
| Result type | Median |
| Measure of spread | 90% Confidence Interval |
| Unit | Months |
| Endpoint classification | Time-to-Event Analysis |
Progression-free survival (PFS) measures the time from randomization until the earlier of documented disease progression or death from any cause. In this trial, progression was defined using tumor assessments: it could involve an increase in the sum of the longest diameters of target lesions, unequivocal worsening of existing non-target lesions, or the appearance of new lesions. For patients without measurable disease, the definition included a lesion becoming measurable or unequivocal progression of a non-target lesion.
This is a time-to-event endpoint. It incorporates both when an event occurs and the fact that some participants may not have had an event by the end of observation. The median PFS is the time at which the estimated survival distribution reaches its midpoint; it does not describe every participant’s experience or the range of individual event times. The registry record reports median PFS in months with 90% confidence intervals.
PFS is used in clinical trials because it summarizes the time until disease progression or death, rather than relying only on a tumor measurement at one assessment. The endpoint is based on a defined event and follow-up period, but its interpretation depends on how progression was assessed, how follow-up ended for participants without an event, and how incomplete observations were handled. Those operational analysis details are not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
Median PFS was 9.3 months in the vismodegib group, with a 90% confidence interval from 7.98 to 10.51 months. In the placebo group, median PFS was 10.1 months, with a 90% confidence interval from 9.43 to 11.33 months. These are group-level median estimates for the intent-to-treat population, defined as all randomized patients.
A confidence interval expresses uncertainty around an estimated quantity under the method used to construct it. The reported intervals are 90% confidence intervals; they indicate that the median estimates are not known with unlimited precision. The interval endpoints are estimates too, not guaranteed bounds on the true value. The registry record does not state the method used to calculate these intervals.
The two reported medians are descriptive summaries. They do not by themselves provide a formal estimate of the relative treatment effect over the full follow-up period. In particular, the record does not include a hazard ratio, a comparative confidence interval, or a sponsor-reported hypothesis test for the primary endpoint. Without those comparative results, the medians alone do not establish the magnitude or statistical uncertainty of a treatment contrast. The overlap of confidence intervals is not a substitute for a formal comparison.
The endpoint definition includes progression or death, whichever came first. Therefore, the medians refer to time without either of those recorded events, not to overall survival, response rate, symptom burden, or quality of life. The timeframe is described as extending from first treatment through the data cut-off date of March 15, 2010, up to 90 weeks. The registry record does not provide additional detail about the maturity of follow-up or the number of participants censored before an event.
The recorded group sizes were 98 for vismodegib and 101 for placebo. Enrollment and group size alone do not show how many participants had a PFS event or how many contributed to each point in the estimated curve. Those event and censoring counts are not reported in the registry record. The statistical displays may help readers inspect the reported outcome, but the written registry results remain the source for the median estimates and their stated uncertainty.
In short, the posted results give median PFS estimates for each randomized group, with their 90% confidence intervals. They do not include the sponsor’s comparative treatment estimate or analysis, so interpretation of the between-group contrast must remain limited to those descriptive summaries.
9. Statistical Methods Explained
Progression-free survival is a time-to-event outcome. Each participant is followed from the defined starting point until the first qualifying event, or until observation ends without a recorded event. In this trial, the starting point is randomization in the endpoint definition, and the event is documented disease progression or death from any cause, whichever occurred first. The registry’s timeframe also describes the endpoint as followed from first treatment through the data cut-off date of March 15, 2010, up to 90 weeks.
What a median means
The median is the midpoint of a distribution, not an average. For a time-to-event outcome, it is the time at which the estimated proportion remaining free of the event reaches one-half. This summary is useful because it can be interpreted in the original time units and does not require the event times to follow a particular symmetric distribution. It is still only one feature of the outcome: it does not show the full pattern of events over time, nor does it describe the experience of every participant.
The reported median PFS was 9.3 months for vismodegib and 10.1 months for placebo. The registry also reports 90% confidence intervals for those medians. A confidence interval conveys uncertainty in an estimate under a specified statistical procedure. Its width reflects the available information and the method used, while the interval itself does not guarantee that the true value lies within its endpoints. The registry record does not state the procedure used to calculate the intervals.
What censoring means
In time-to-event analyses, a participant may reach the end of available follow-up without a recorded event, or leave observation before an event is documented. Such an observation is generally treated as censored: it contributes information up to the last known follow-up time, but the event time is not known. This is a general explanation of time-to-event methods, not a statement about the handling of individual participants in this study. The registry record does not report censoring counts, the censoring rules, or the assumptions used in the analysis.
Why a comparative estimate matters
Separate medians describe each randomized group. A comparative time-to-event analysis can use information across follow-up to estimate how the event experience differs between groups. A hazard ratio is one common type of comparative measure in time-to-event research, but no sponsor-reported hazard ratio is present in the registry record. Nor is a comparative confidence interval or p-value reported for the primary endpoint. Consequently, the available figures do not permit a full account of the sponsor’s comparative statistical analysis.
The record identifies the study as randomized and double-blind, and says randomization was stratified by chemotherapy regimen and baseline RECIST-measurable disease status. Stratification is a design feature that aims to balance specified categories across randomized groups. The record does not state whether the primary analysis adjusted for these factors, how any model was specified, or whether other covariates were included.
Over-dispersion and model assumptions
General statistical context: over-dispersion occurs when variability in observed data exceeds what a model assumes. When it is present and not accounted for, uncertainty estimates from a model can be too small or otherwise poorly calibrated. Over-dispersion is most directly relevant to particular count-data models and is not something that can be diagnosed from median PFS values alone. The registry record does not report a model specification or an assessment of over-dispersion for this endpoint.
Time-to-event analyses also depend on decisions about the event definition, follow-up, censoring, and the statistical method used to estimate the distribution or compare groups. The disease-progression definition is reported, including criteria for participants with and without measurable disease. The detailed assessment schedule, adjudication procedures, censoring rules, and method for calculating medians and confidence intervals are not reported in the registry record.
Sample-size illustrations are planning calculations, not trial outcomes and not observed power. The stated planning assumptions refer to a two-sided significance level of 0.05, equal allocation, a normal approximation, and an effect specified as a fraction of the observed effect. For time-to-event illustrations, the stated method concerns the total number of events. Numerical planning estimates are not reported in the registry record, and the record does not say that these assumptions were the trial’s own design justification. The trial’s actual design rationale and sample-size justification are not reported in the registry record.
10. Multiplicity, Missing Data and Analysis Populations
The registry record lists progression-free survival as the primary outcome and one secondary outcome concerning PFS in patients with various degrees of Hedgehog antigen tumor expression. It does not report a prespecified multiplicity strategy, a hierarchy of hypotheses, or adjustments for multiple comparisons. Without those details, the record does not establish how error rates across primary and secondary questions were controlled or how secondary findings should be interpreted.
The record identifies the primary endpoint population as intent-to-treat, meaning all randomized patients. This definition makes the randomized groups the basis for the stated primary outcome population. The registry record does not report a separate per-protocol population, a safety analysis population definition, or how participants with missing outcome assessments were handled.
Missingness in a time-to-event outcome can involve loss of follow-up, incomplete assessments, or an event not observed before the data cut-off. General statistical methods often account for incomplete follow-up through censoring, but the specific censoring rules and assumptions used in this trial are not reported in the registry record. Counts of censored participants, missing endpoint data, and sensitivity analyses addressing missingness are also not reported.
The record does not provide the primary analysis model, a sponsor-reported comparative estimate, or a hypothesis-test result. It therefore does not describe whether any analysis adjustments or alternative analyses were used to assess robustness. These omissions limit the ability to reconstruct the analysis and to judge how multiplicity and incomplete follow-up affected the reported 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 |
|---|---|---|---|
| Placebo With FOLFOX+Bevacizumab | 21 | 62 | 33.9% |
| Vismodegib (GDC-0449) With FOLFOX+Bevacizumab | 29 | 61 | 47.5% |
| Placebo With FOLFIRI+Bevacizumab | 9 | 36 | 25.0% |
| Vismodegib (GDC-0449) With FOLFIRI+Bevacizumab | 18 | 37 | 48.6% |
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 |
|---|---|
| Placebo With FOLFOX+Bevacizumab | 62 of 62 |
| Vismodegib (GDC-0449) With FOLFOX+Bevacizumab | 61 of 61 |
| Placebo With FOLFIRI+Bevacizumab | 36 of 36 |
| Vismodegib (GDC-0449) With FOLFIRI+Bevacizumab | 36 of 37 |
Most frequent serious adverse event terms
| Event term | Organ system | Placebo With FOLFOX+Bevacizumab | Vismodegib (GDC-0449) With FOLFOX+Bevacizumab | Placebo With FOLFIRI+Bevacizumab | Vismodegib (GDC-0449) With FOLFIRI+Bevacizumab |
|---|---|---|---|---|---|
| Dehydration | Metabolism and nutrition disorders | 2 of 62 | 7 of 61 | 0 of 36 | 2 of 37 |
| Pulmonary Embolism | Respiratory, thoracic and mediastinal disorders | 1 of 62 | 5 of 61 | 3 of 36 | 2 of 37 |
| Pneumonia | Infections and infestations | 1 of 62 | 2 of 61 | 1 of 36 | 1 of 37 |
| Deep Vein Thrombosis | Vascular disorders | 0 of 62 | 4 of 61 | 1 of 36 | 0 of 37 |
| Abdominal Pain | Gastrointestinal disorders | 1 of 62 | 2 of 61 | 0 of 36 | 1 of 37 |
| Nausea | Gastrointestinal disorders | 1 of 62 | 2 of 61 | 0 of 36 | 1 of 37 |
| Vomiting | Gastrointestinal disorders | 1 of 62 | 2 of 61 | 0 of 36 | 1 of 37 |
| Diarrhoea | Gastrointestinal disorders | 1 of 62 | 0 of 61 | 1 of 36 | 2 of 37 |
| Small Intestinal Obstruction | Gastrointestinal disorders | 2 of 62 | 2 of 61 | 0 of 36 | 0 of 37 |
| Renal Failure Acute | Renal and urinary disorders | 1 of 62 | 3 of 61 | 0 of 36 | 0 of 37 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Placebo With FOLFOX+Bevacizumab | Vismodegib (GDC-0449) With FOLFOX+Bevacizumab | Placebo With FOLFIRI+Bevacizumab | Vismodegib (GDC-0449) With FOLFIRI+Bevacizumab |
|---|---|---|---|---|---|
| Fatigue | General disorders | 42 of 62 | 40 of 61 | 29 of 36 | 27 of 37 |
| Nausea | Gastrointestinal disorders | 40 of 62 | 38 of 61 | 21 of 36 | 23 of 37 |
| Diarrhoea | Gastrointestinal disorders | 36 of 62 | 30 of 61 | 29 of 36 | 22 of 37 |
| Vomiting | Gastrointestinal disorders | 16 of 62 | 23 of 61 | 15 of 36 | 19 of 37 |
| Decreased Appetite | Metabolism and nutrition disorders | 14 of 62 | 31 of 61 | 10 of 36 | 18 of 37 |
| Neutropenia | Blood and lymphatic system disorders | 26 of 62 | 19 of 61 | 13 of 36 | 14 of 37 |
| Constipation | Gastrointestinal disorders | 21 of 62 | 20 of 61 | 13 of 36 | 12 of 37 |
| Neuropathy Peripheral | Nervous system disorders | 34 of 62 | 19 of 61 | 6 of 36 | 2 of 37 |
| Epistaxis | Respiratory, thoracic and mediastinal disorders | 16 of 62 | 16 of 61 | 17 of 36 | 6 of 37 |
| Anaemia | Blood and lymphatic system disorders | 21 of 62 | 14 of 61 | 11 of 36 | 6 of 37 |
Serious events with the highest arm-level rate: dehydration (11.5%), pulmonary embolism (8.3%), deep vein thrombosis (6.6%), diarrhoea (5.4%), ileus (4.9%).
The serious adverse-event summaries are separated by chemotherapy regimen and randomized study drug. For FOLFOX plus bevacizumab, the record lists 21 participants with serious adverse events among 62 at risk in the placebo group, and 29 among 61 at risk in the vismodegib group. For FOLFIRI plus bevacizumab, it lists 9 among 36 at risk in the placebo group and 18 among 37 at risk in the vismodegib group. These are counts of participants with at least one serious adverse event as recorded in the registry summary, not counts of all event episodes.
The listed serious adverse-event terms include dehydration at 11.5%, pulmonary embolism at 8.3%, deep vein thrombosis at 6.6%, diarrhoea at 5.4%, ileus at 4.9%, and mucosal inflammation at 4.9%. The record does not clarify in this summary whether these percentages refer to participants, events, or another denominator, so they should be read as registry-listed percentages rather than recomputed or interpreted as rates.
These safety summaries are descriptive. They do not establish that an event was caused by a particular study drug, and the group counts are divided by chemotherapy regimen rather than presented as a single randomized comparison. Death counts are not reported in the registry record. The registry record also does not provide enough detail to assess exposure duration, event timing, or adjustments for differences between groups.
12. What the Result Does, and Does Not, Mean
The results describe median progression-free survival in a randomized phase II study of vismodegib versus placebo, with both groups receiving chemotherapy and bevacizumab. The vismodegib group had a reported median of 9.3 months, with a 90% confidence interval from 7.98 to 10.51 months. The placebo group had a reported median of 10.1 months, with a 90% confidence interval from 9.43 to 11.33 months.
Those estimates are specific to the trial’s population and treatment setting: patients with metastatic colorectal cancer receiving first-line therapy, with the chemotherapy regimen selected by the treating physician and patient. The primary analysis population is described as all randomized patients. The findings should not be generalized automatically to other populations, treatment settings, or regimens that are not described in the registry record.
The posted results do not include a sponsor-reported hazard ratio, comparative confidence interval, or p-value for the primary endpoint. The medians can be read as separate group summaries, but they do not quantify the full between-group effect across follow-up or show how statistically uncertain that comparison is. Nor do they establish whether differences in the observed medians are due to treatment, chance, follow-up patterns, or other factors.
Progression-free survival is not the same as overall survival, tumor response, quality of life, or symptom control. The endpoint combines time to documented progression or death, and the registry record does not report those components separately. The listed serious adverse events provide descriptive safety counts, but they do not by themselves establish causation or a complete comparison of harms.
Accordingly, the registry record supports a description of the reported PFS medians and safety summaries, not a definitive conclusion about comparative benefit or harm. The details needed for a fuller statistical assessment—including the comparative primary analysis, missing-data handling, and multiplicity approach—are not reported in the registry record.
13. Why This Trial Matters Statistically
This trial illustrates why the type of outcome and the form of reporting both matter. Progression-free survival is a time-to-event endpoint, so follow-up duration and incomplete observation are central to interpretation. A median gives a compact summary in months, but does not show the whole event-time distribution. The reported 90% confidence intervals add information about precision for each median, while still leaving the comparative uncertainty unresolved when no comparative estimate is reported.
Randomization and double-blinding are important design features for a treatment comparison. Stratification by chemotherapy regimen and baseline RECIST-measurable disease status also signals that these factors were considered in the assignment process. However, design features do not replace a clear report of the analysis: readers also need the treatment-effect estimate, its uncertainty, the model or method used, and the handling of censoring and missing data.
The study’s treatment context adds another interpretive point. Patients received one of two chemotherapy options, selected by the treating physician and patient, with bevacizumab in both randomized groups. The randomized contrast was vismodegib versus placebo on top of these treatment regimens. Safety counts are accordingly shown by chemotherapy regimen and randomized study drug, and should not be conflated with the primary endpoint’s overall randomized groups.
For clinical researchers and biostatisticians, the record is a useful example of the distinction between reporting group-specific endpoint summaries and reporting a comparative analysis. It also shows why registry results should be read alongside the stated endpoint definition, population, follow-up timeframe, and limitations in analysis detail. Here, the record gives the medians and confidence intervals but does not report the sponsor’s comparative estimate or detailed statistical plan.
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 contains group-specific median PFS estimates and 90% confidence intervals, but does not report a sponsor-reported hazard ratio, comparative confidence interval, or p-value. This limits assessment of the size and precision of the randomized treatment contrast. The reported medians alone do not provide a complete time-to-event comparison.
Several analysis details are not reported in the registry record: the method used to estimate medians and confidence intervals, the primary analysis model, censoring rules, the number of PFS events, censoring counts, and sensitivity analyses. The record defines the endpoint and the intent-to-treat population, but does not explain how missing or incomplete follow-up was handled.
The timeframe is stated as from first treatment through the data cut-off date of March 15, 2010, up to 90 weeks. More detailed information about follow-up distribution and endpoint assessment procedures is not reported in the registry record. The record also does not report a multiplicity plan for the primary and secondary outcomes or the protocol’s sample-size justification.
The safety summaries are stratified by chemotherapy regimen and study drug, but the record does not give the safety analysis population definition, event timing, exposure information, or deaths. The listed serious adverse-event percentages are not accompanied by a denominator definition in the summary. As a result, they should not be treated as a complete measure of comparative safety or as evidence that an event was caused by a particular treatment.
Finally, chemotherapy regimen was selected by the treating physician and patient, rather than being the randomized contrast described in the record. Results concern the randomized addition of vismodegib or placebo within that treatment setting; they do not isolate comparisons between FOLFOX and FOLFIRI.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: A Study of Vismodegib (GDC-0449, Hedgehog Pathway Inhibitor) With Concurrent Chemotherapy and Bevacizumab As First-Line Therapy for Metastatic Colorectal Cancer — NCT00636610.
- Registry record last updated 2017-06-08; status last verified 2017-05.
- Results first posted 2012-07-03.
- 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
NCT00636610 is a completed randomized, placebo-controlled, double-blind phase II study of vismodegib added to chemotherapy and bevacizumab as first-line therapy for metastatic colorectal cancer. Enrollment was 199. Patients received vismodegib 150 mg or placebo alongside Modified FOLFOX or FOLFIRI and bevacizumab; the chemotherapy regimen was selected by the treating physician and patient.
The primary outcome was progression-free survival, defined as time from randomization to documented disease progression or death from any cause, whichever occurred first. The intent-to-treat population included all randomized patients. Median PFS was 9.3 months for vismodegib and 10.1 months for placebo, with respective 90% confidence intervals of 7.98 to 10.51 months and 9.43 to 11.33 months.
The registry record does not report a sponsor-reported comparative hazard ratio, confidence interval, or p-value for the primary outcome. It also does not report detailed analysis methods, censoring rules, missing-data procedures, or the multiplicity strategy. Serious adverse-event counts are reported by chemotherapy regimen and randomized study drug.