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 This Is An Open-Label, Non-Comparative Study Designed To Evaluate A Short Course Of IV Anidulafungin, Followed Optionally By Oral Voriconazole, For The Treatment Of Candidemia And Invasive Candidiasis (NCT00548262), a non-randomized phase 4 study. The primary outcome is Number of Participants for Global Response (Based on Clinical and Microbiological Success or Failure) at End of Treatment.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00548262 |
| Phase | Phase 4 |
| Condition | Candidemia, Invasive Candidiasis |
| Allocation | Non-Randomized |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 54 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Pfizer |
| Results posted | Yes |
2. Clinical Question
Population
Hospitalized patients with documented candidemia or invasive candidiasis were the intended population. The primary analysis population was the modified Intent-to-Treat population: participants who took at least one dose of study treatment and had a positive baseline culture for a Candida species within 96 hours before study entry. The registry lists enrollment of 54 participants, but the number meeting the primary analysis population definition is not reported in the registry record.
Intervention
The treatment approach began with intravenous anidulafungin, with oral voriconazole as an optional subsequent treatment. The registry title describes this as a short course, but the exact treatment duration and the criteria for using optional voriconazole are not reported in the registry record.
Comparator
There was no concurrent comparator group. The study is recorded as non-randomized, unmasked, and single-group. Its results therefore describe outcomes among participants receiving the study treatment approach; they do not estimate a randomized between-treatment contrast.
Primary question
The primary objective was to estimate the global response rate at end of treatment, up to Day 42. Global success required both clinical and microbiological success. The registry describes computing clinical, microbiological, and global response rates with 95% confidence intervals and states that no hypotheses would be tested. The numerical global response result and its confidence interval are not reported in the registry record.
3. Trial Design
NCT00548262 is recorded as a Phase 4, completed, open-label, non-comparative study. Its allocation is non-randomized, its masking is listed as none, and its model is single-group. Enrollment was 54 participants. The study evaluated intravenous anidulafungin, followed optionally by oral voriconazole, for documented candidemia or invasive candidiasis in hospitalized patients. The registry records a start date of 2008-02 and primary completion in 2009-10.
Because the study had no concurrent control group, its design supports a description of outcomes in the treated group, not a direct estimate of how outcomes would differ under another treatment. Non-random allocation and the absence of masking also mean the registry does not describe a blinded comparison that could separate treatment effects from other influences on assessment or outcome. These are features of the design, not numerical findings about the treatment.
The primary objective was estimation rather than hypothesis testing: the registry says clinical, microbiological, and global response rates and their 95% confidence intervals would be computed, with no hypotheses tested. It does not report a protocol-based sample-size justification, the intended precision target, or an inferential comparison. The exact treatment schedule, the use criteria for optional voriconazole, and the number of participants who completed each treatment step are not reported in the registry record.
The record lists 22 outcome measures and 98 analyses. Secondary outcome descriptions include global response at different assessment times, response by Candida species isolated at baseline, response in baseline-risk subgroups, and response by APACHE II score. The existence of those listed measures does not itself indicate that every result is available or that any subgroup contrast was prespecified for confirmatory testing.
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.
Before assignment: The planned sample size for this study was 210 subjects; however, due to slow enrollment, only 54 subjects were screened and randomized.
Overall Study
| Stage | Anidulafungin-Voriconazole |
|---|---|
| STARTED | 54 |
| COMPLETED | 22 |
| NOT COMPLETED | 32 |
Reasons for not completing this period:
| Reason | Anidulafungin-Voriconazole |
|---|---|
| Death | 21 |
| Adverse Event | 2 |
| Lack of Efficacy | 4 |
| Lost to Follow-up | 1 |
| Other | 3 |
| Withdrawal by Subject | 1 |
Analysis population for the primary outcome, as defined in the registry: Modified Intent-to-Treat population (MITT): all Intent-to-Treat (ITT) participants (took at least 1 dose of study treatment) and with a positive baseline culture for a Candida spp within 96 hours before entry into the study. Success=clinical and microbiological success; Failure=all other combinations. Missing or indeterminate set to Failure.
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 | Anidulafungin-Voriconazole |
|---|---|---|
| Participants analysed | 54 | |
| Age, Customized: Between 18 and 44 years | participants | 18 |
| Age, Customized: Between 45 and 64 years | participants | 18 |
| Age, Customized: ≥ 65 years | participants | 18 |
| Sex: Female, Male: Female | Participants | 32 |
| Sex: Female, Male: Male | Participants | 22 |
6. Primary Endpoint
The registry lists the primary outcome as Number of Participants for Global Response (Based on Clinical and Microbiological Success or Failure) at End of Treatment, measured over End of Treatment (EOT) (up to Day 42).
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint counts participants classified as having global success or failure at end of treatment, up to Day 42. Success required clinical success and microbiological success together. Clinical success meant cure, defined as resolution of Candida signs and symptoms, or improvement, defined as significant but incomplete resolution. Clinical failure included receiving at least 3 doses of anidulafungin with no significant improvement in signs and symptoms, or death due to Candida.
Microbiological success meant eradication, defined as a negative culture for the baseline Candida species, or presumed eradication when a follow-up culture was unavailable and the clinical outcome was success. Microbiological failure meant persistence, defined as a positive culture for at least one baseline Candida species, or presumed persistence when a follow-up culture was unavailable and the clinical outcome was failure. The endpoint definition therefore combines clinical status with culture findings, and it uses the clinical outcome to classify cases without an available follow-up culture.
This composite endpoint is intended to summarize both clinical and microbiological response rather than either component alone. That makes its interpretation dependent on both components and on the stated rules for unavailable cultures. It is defined for the modified Intent-to-Treat population, not automatically for every enrolled participant. The registry record does not report the number in that population, the success count, the failure count, or the resulting response rate. It also does not report the numerical 95% confidence interval for the endpoint.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The central statistical aim was to estimate a global response rate, not to test a treatment against a control. The registry explicitly states that response rates and 95% confidence intervals would be computed and that no hypotheses would be tested. This framing matters: an estimate describes the observed proportion under the endpoint definition, while a confidence interval describes uncertainty around that estimate. Neither quantity, by itself, establishes what would have happened to the same patients under another treatment.
The registry record does not report the primary success count, failure count, analysis-population denominator, response-rate estimate, or confidence interval limits. Consequently, the numerical size and precision of the primary result cannot be assessed from the record details available. Enrollment of 54 is not interchangeable with the primary analysis denominator, because the endpoint population requires treatment exposure and a qualifying positive baseline culture. The number meeting those criteria is not reported in the registry record.
The single-group, non-randomized, open-label design places a clear boundary on interpretation. Descriptive outcomes can characterize the participants included in the analysis, but there is no concurrent randomized control group for estimating a comparative treatment effect. Changes in participants’ condition, other care, selection into the analysis population, and assessment practices cannot be disentangled as treatment contrasts using a single-group response rate. This is a design limitation, not evidence that any particular factor changed the result.
The global endpoint is a joint classification. Clinical and microbiological success both had to be present for success, while the listed failure rules and unavailable-culture conventions determine how other combinations are categorized. Thus, the response rate would not be a simple clinical improvement rate or a culture-eradication rate alone. Separate numerical component results are not reported in the registry record.
The record also describes outcomes by Candida species, baseline risk factors, assessment time, and APACHE II score. Such analyses can describe variation across groups, but without the corresponding estimates, denominators, and uncertainty intervals, their findings cannot be evaluated. The registry does not report whether these analyses were exploratory or how multiplicity was handled. The count of recorded analyses does not establish that all comparisons were planned as confirmatory tests.
For safety, the record lists serious adverse events affecting 29 of 54 participants at risk and other adverse events affecting 26 of 54 at risk. It also lists serious-event terms with percentages. These summaries describe reported events in this group; they do not establish that the study treatment caused them. The information available does not provide the detail needed to compare risk with another treatment or to interpret all event timing and attribution.
9. Statistical Methods Explained
What does an estimated response rate mean?
General statistical explanation: for a binary outcome such as success or failure, a response rate is the proportion of participants in the defined analysis population who meet the success criteria. Its meaning depends on the endpoint definition and denominator. In this study, success required both clinical and microbiological success, and the designated population was the modified Intent-to-Treat population. Enrollment alone is not necessarily the denominator for that estimate.
The registry states that clinical, microbiological, and global response rates would be computed. The numerical estimates are not reported in the registry record. Without the relevant count and denominator, a reader cannot determine the observed rate or check how many participants contributed to the endpoint. Nor can the registry entries establish whether the endpoint was available for every eligible participant.
How should a confidence interval be read?
General statistical explanation: a confidence interval communicates the uncertainty associated with an estimate under the statistical procedure used. For a response rate, it gives a range of values compatible with the data and that procedure. A narrower interval generally indicates greater precision, while a wider interval indicates less precision. The interval is not a guarantee that the true value lies inside its limits, and it does not convert a single-group estimate into a treatment comparison.
The registry says 95% confidence intervals would be computed, but the numerical interval limits and the method used to calculate them are not reported in the registry record. It is therefore not possible to assess the precision of the primary estimate or determine whether an interval method accounted for any particular feature of the data. No calculation method should be inferred from the stated confidence level alone.
What does the single-group design permit?
General statistical explanation: a single-group study can estimate outcomes among the participants observed under its treatment approach. A randomized control group is ordinarily needed to estimate a causal contrast between assigned treatment strategies while balancing other influences in expectation. This trial is recorded as non-randomized, unmasked, and single-group, so its primary objective is appropriately described as estimation of response rather than a controlled treatment comparison.
The absence of a control does not make the observed outcomes meaningless; it limits the question they answer. A response estimate can describe the study group, subject to the endpoint and population definitions. It cannot establish the response that would have occurred with an alternative treatment, or isolate the contribution of anidulafungin from optional subsequent voriconazole and other care. The registry does not report a comparative hypothesis test.
Why does the endpoint combine two kinds of success?
General statistical explanation: a composite outcome combines multiple criteria into a single classification. It can capture more than one dimension of outcome, but the overall result depends on the component definitions and on how their combinations are classified. Here, global success required clinical and microbiological success. A participant who did not meet both conditions was not classified as a global success under the stated definition.
The endpoint also specifies how unavailable follow-up cultures are handled. An unavailable culture is treated as presumed eradication when clinical outcome is success and presumed persistence when clinical outcome is failure. These rules avoid leaving those cases entirely unclassified, but they mean that the microbiological component is not always based on an observed follow-up culture. The number of participants affected by these rules is not reported in the registry record.
What can subgroup and repeated-time analyses establish?
General statistical explanation: subgroup estimates can describe response within defined participant categories, while assessments at different times describe outcomes under the corresponding time-specific definitions. Their interpretation depends on subgroup size, missing outcome data, and the statistical plan. Small or imbalanced groups can yield imprecise estimates. Examining many outcomes or subgroups can also increase the chance of a seemingly notable pattern arising by chance if many tests are performed.
The registry lists response analyses by baseline Candida species, baseline risk factors, assessment time, and APACHE II score. It records 98 analyses, but the numerical results, subgroup denominators, confidence intervals, and multiplicity approach are not reported in the registry record. The analysis count alone does not show which analyses were primary, exploratory, or intended to support a formal claim.
How should planning calculations be distinguished from trial results?
General statistical explanation: sample-size planning calculations explore how many participants might be needed under specified assumptions. They are not observed outcomes and do not show the probability that a study has detected a real effect after the data are collected. The planning illustrations associated with this study use a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation, with the effect to detect set as a stated fraction of the observed effect. For time-to-event calculations, the stated quantity is total events; for other calculations, it is participants per arm.
Those assumptions describe planning illustrations, not the design recorded for this trial. The actual study is single-group and non-comparative, and the registry does not report its own sample-size justification. The illustrations are not observed power and should not be read as evidence that the trial was designed or powered for a randomized two-arm comparison. The observed effect and any planning results are not numerically reported in the registry record details available.
10. Multiplicity, Missing Data and Analysis Populations
The record lists a primary global response outcome and a range of secondary measures, including response by Candida species, baseline risk factors, assessment time, and APACHE II score. It also records 22 outcome measures and 98 analyses. The stated primary objective was estimation: response rates and 95% confidence intervals would be computed, with no hypotheses tested. A formal hypothesis-testing plan, any multiplicity adjustment, and a hierarchy for interpreting secondary outcomes are not reported in the registry record.
General statistical explanation: when many outcomes, time points, or subgroups are examined, the chance of observing an apparently unusual result among them can increase. Adjustment procedures or a prespecified testing hierarchy can address some multiplicity concerns, but the appropriate approach depends on the goals and statistical plan. In the absence of reported details, the subgroup and secondary analyses should be read as descriptive rather than as evidence of a confirmed difference.
The primary population is defined as modified Intent-to-Treat: participants who took at least one dose and had a positive baseline Candida culture within 96 hours before entry. The registry does not report the number meeting those criteria, the number with outcome data, or how many participants were excluded from the primary analysis. The endpoint definition classifies unavailable follow-up cultures as presumed eradication or presumed persistence according to clinical outcome. The frequency of unavailable cultures and any other missing-data handling are not reported in the registry record.
The record does not report an interim-analysis plan, a protocol-based sample-size justification, or further details of the statistical analysis plan. Those omissions prevent assessment of planned monitoring, the intended precision of the estimate, and the prespecified handling of all outcomes and missing observations.
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 |
|---|---|---|---|
| Anidulafungin-Voriconazole | 29 | 54 | 53.7% |
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 |
|---|---|
| Anidulafungin-Voriconazole | 26 of 54 |
Most frequent serious adverse event terms
| Event term | Organ system | Anidulafungin-Voriconazole |
|---|---|---|
| Septic shock | Infections and infestations | 11 of 54 |
| Cardio-respiratory arrest | Cardiac disorders | 4 of 54 |
| Multi-organ disorder | General disorders | 4 of 54 |
| Death | General disorders | 3 of 54 |
| Acute respiratory failure | Respiratory, thoracic and mediastinal disorders | 3 of 54 |
| Cardiac arrest | Cardiac disorders | 2 of 54 |
| Renal failure | Renal and urinary disorders | 2 of 54 |
| Hypotension | Vascular disorders | 2 of 54 |
| Shock haemorrhagic | Vascular disorders | 2 of 54 |
| Blood disorder | Blood and lymphatic system disorders | 1 of 54 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Anidulafungin-Voriconazole |
|---|---|---|
| Hypokalaemia | Metabolism and nutrition disorders | 10 of 54 |
| Anaemia | Blood and lymphatic system disorders | 5 of 54 |
| Pyrexia | General disorders | 4 of 54 |
| Hypertension | Vascular disorders | 4 of 54 |
| Leukopenia | Blood and lymphatic system disorders | 3 of 54 |
| Thrombocytopenia | Blood and lymphatic system disorders | 3 of 54 |
| Diarrhoea | Gastrointestinal disorders | 3 of 54 |
| Vomiting | Gastrointestinal disorders | 3 of 54 |
| Hyperglycaemia | Metabolism and nutrition disorders | 3 of 54 |
| Hyperkalaemia | Metabolism and nutrition disorders | 3 of 54 |
Serious events with the highest arm-level rate: septic shock (20.4%), cardio-respiratory arrest (7.4%), multi-organ disorder (7.4%), death (5.6%), acute respiratory failure (5.6%).
The registry reports serious adverse events affecting 29 of 54 participants at risk and other adverse events affecting 26 of 54 participants at risk in the Anidulafungin-Voriconazole group. These are participant counts in the registry safety summary. They should be read as descriptions of events recorded among the study group, not as estimates of excess risk relative to a control group.
The listed serious-event terms include septic shock at 20.4%, cardio-respiratory arrest at 7.4%, multi-organ disorder at 7.4%, death at 5.6%, acute respiratory failure at 5.6%, and cardiac arrest at 3.7%. These entries are event-term summaries; they do not provide a complete account of each participant’s course, timing, severity, or relationship to treatment. The registry record does not report the overall death count in the safety summary.
General statistical explanation: adverse-event counts can include events arising from the underlying illness as well as events that may be related to treatment. A single-group study cannot estimate how these counts would compare under an alternative treatment. The reported figures therefore describe the observed safety experience in this group, while causality and comparative safety are not established by these summaries. Detailed event attribution and a comparative safety analysis are not reported in the registry record.
12. What the Result Does, and Does Not, Mean
The study was designed to estimate global response among hospitalized participants with documented candidemia or invasive candidiasis who met the modified Intent-to-Treat criteria. The endpoint combined clinical and microbiological success at end of treatment, up to Day 42. Its definitions include specific rules for clinical failure, culture persistence, and follow-up cultures that are unavailable. Those rules determine what the primary outcome represents.
The registry states that response rates and 95% confidence intervals would be computed, but the primary response count, denominator, estimate, and confidence interval limits are not reported in the registry record. As a result, the magnitude and precision of the primary outcome cannot be described numerically from these record details. Enrollment of 54 participants does not supply the missing endpoint denominator because the primary analysis population has additional eligibility criteria.
The single-group, non-randomized, open-label design means the study provides no concurrent randomized comparison. Its response outcomes cannot establish how the same population would have fared under another treatment or separate the treatment approach from other influences on outcome. The optional use of oral voriconazole also means the recorded approach includes more than the initial intravenous anidulafungin treatment; details of its use are not reported in the registry record.
The registry’s safety counts and serious-event terms describe events recorded among participants at risk. They do not by themselves establish that treatment caused an event, nor do they estimate comparative safety. The registry also lists secondary and subgroup outcomes, but their numerical findings and the approach to multiplicity are not reported in the registry record.
In short, the record defines a descriptive response question and the population and endpoint used to address it. It does not report the numerical primary result needed to judge the observed response or its precision, and the design does not support a controlled causal comparison. Those boundaries are essential when interpreting what the study can and cannot establish.
13. Why This Trial Matters Statistically
This study is statistically informative as an example of the distinction between estimating an outcome and comparing treatments. Its stated objective was to estimate response rates with confidence intervals, and the registry explicitly says no hypotheses would be tested. That approach describes the intended role of the primary analysis without implying a treatment effect relative to a control.
The endpoint also illustrates how a clinically meaningful summary can depend on operational definitions. Global success required both clinical and microbiological success, while missing follow-up cultures were classified according to the clinical outcome. These choices shape the response rate and should be understood before interpreting any reported estimate. The registry record does not report the numerical result or the number of participants affected by the unavailable-culture rules.
The design highlights why the comparator matters for inference. A single-group response can describe outcomes in the enrolled analysis population, but it does not show how those outcomes compare with an alternative strategy. This distinction is particularly important when a study is open-label and non-randomized: the design does not provide a randomized, masked comparison to separate treatment effects from other influences.
The listed secondary analyses also make multiplicity and transparency relevant. The record includes response evaluations by species, baseline risks, assessment time, and APACHE II score, with 98 analyses recorded. Without a reported analysis hierarchy or multiplicity plan, those results would need cautious descriptive interpretation. Overall, the trial illustrates how endpoint definitions, analysis populations, study design, and completeness of reported estimates jointly determine the strength of statistical conclusions.
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 primary limitation for interpretation is that the numerical global response result is not reported in the registry record. The success and failure counts, analysis denominator, response-rate estimate, and 95% confidence interval limits are unavailable in the record details. This prevents assessment of the observed outcome and its statistical precision.
The registry lists enrollment of 54, but the primary endpoint applies to the modified Intent-to-Treat population. That population requires at least one dose of study treatment and a positive baseline Candida culture within 96 hours before entry. Its size and the number with evaluable endpoint data are not reported. Enrollment therefore cannot stand in for the primary analysis denominator.
The single-group, non-randomized, open-label design provides no concurrent control for estimating a comparative effect. The study evaluates an approach involving intravenous anidulafungin and optional oral voriconazole, but treatment duration, criteria for optional voriconazole, and detailed treatment exposure are not reported in the registry record. The contribution of each treatment component cannot be separated from the available design description.
The global endpoint combines clinical and microbiological criteria and includes presumptive classifications when follow-up cultures are unavailable. The number of participants affected by those rules and the handling of other missing information are not reported. The registry also lists many secondary analyses but does not report a multiplicity strategy, a detailed statistical analysis plan, or whether subgroup analyses were exploratory.
Finally, the registry does not report a protocol-based sample-size justification or an interim-analysis plan. Safety figures are descriptive and lack a concurrent comparison; detailed event attribution and the overall death count are not reported in the safety summary. These limitations constrain interpretation of both effectiveness and safety from the registry record.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: This Is An Open-Label, Non-Comparative Study Designed To Evaluate A Short Course Of IV Anidulafungin, Followed Optionally By Oral Voriconazole, For The Treatment Of Candidemia And Invasive Candidiasis — NCT00548262.
- Registry record last updated 2011-01-17; status last verified 2010-12.
- Results first posted 2011-01-17.
- 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
NCT00548262 is a completed Phase 4, open-label, non-randomized, single-group study with enrollment of 54 participants. It evaluated intravenous anidulafungin followed optionally by oral voriconazole for documented candidemia or invasive candidiasis in hospitalized patients. The primary objective was to estimate clinical, microbiological, and global response rates with 95% confidence intervals, without hypothesis testing.
The primary endpoint was global response at end of treatment, up to Day 42, in the modified Intent-to-Treat population. Success required both clinical and microbiological success under the definitions in the registry. The numerical primary result, its denominator, and its confidence interval are not reported in the registry record. The design has no concurrent control group, so the study describes outcomes in its treatment group rather than a randomized treatment contrast.
The registry lists 22 outcome measures and 98 analyses, along with safety counts and serious-event terms. A detailed multiplicity approach, sample-size justification, interim-analysis plan, and further missing-data procedures are not reported in the registry record.