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 Study to Evaluate the Efficacy, Safety and Immunogenicity of Influenza Vaccine in Healthy Subjects (Aged 6 to <72 Months) Versus Control Vaccines (NCT00644059), a randomized phase 3 study. The primary outcome is Number of Subjects (Unprimed) 6 to <36 Months Age With Local and Systemic Reactions After Any Vaccination for All Seasons, Comparison of Adjuvanted Trivalent Influenza Vaccine (aTIV) and Flu Vaccine Control..
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00644059 |
| Phase | Phase 3 |
| Condition | Influenza, Human |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Single |
| Enrollment | 4902 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Novartis |
| Results posted | Yes |
2. Clinical Question
Population
Healthy, unprimed children aged 6 to <36 months are the population specified for the primary outcome. The broader trial enrolled healthy subjects aged 6 to <72 months. For the primary safety analysis, the registry describes the Safety set as exposed subjects who provided post-baseline safety data.
Intervention
The intervention was an adjuvanted trivalent inactivated subunit influenza vaccine, abbreviated aTIV in the registry record. The study evaluated one or two intramuscular doses; the listed vaccine groups include 0.25 and 0.5 dose designations.
Comparator
The primary comparison was aTIV against a flu-vaccine control. The control could be a non-adjuvanted trivalent inactivated subunit influenza vaccine or a non-adjuvanted trivalent inactivated split influenza vaccine. The wider trial also included non-influenza control vaccines: meningococcal C conjugate vaccine or tick-borne encephalitis vaccine.
Primary question
Among unprimed children aged 6 to <36 months, how many experienced each local or systemic reaction within 7 days after any vaccination, comparing aTIV with flu-vaccine control across all seasons? The endpoint is a safety count, not a direct measure of protection against influenza. The registry record does not report the category-specific primary-outcome results, so the comparison cannot be quantified from that record.
3. Trial Design
NCT00644059 is recorded as a completed, randomized, observer-blind, controlled, multicenter Phase III trial using a parallel design. The title describes evaluation of the efficacy, safety, and immunogenicity of one or two intramuscular doses of influenza vaccine against control vaccines in healthy subjects aged 6 to <72 months. The registry lists enrollment of 4902.
The experimental vaccine was an adjuvanted trivalent inactivated subunit influenza vaccine. Influenza-vaccine controls were non-adjuvanted trivalent inactivated subunit or split influenza vaccines. Non-influenza controls were meningococcal C conjugate vaccine or tick-borne encephalitis vaccine. The listed groups distinguish 0.25 and 0.5 dose designations for the adjuvanted and flu-control vaccines. The brief description also refers to one or two injections and those dose volumes. The registry does not give enough information to reconstruct every assignment and dosing sequence from these details alone.
The primary outcome concerns local and systemic reactions in unprimed subjects aged 6 to <36 months, with reactions assessed within 7 days after any vaccination across all seasons. The described analysis population is the Safety set: exposed subjects who provided post-baseline safety data. This differs from the overall age range in the study title. Several secondary outcomes address safety, virus-confirmed influenza, influenza-like illness, and activity lost because of illness. The registry lists 21 outcome measures and 57 analyses. The exact allocation procedure, blinding procedures beyond observer-blind status, and detailed analysis plan are not reported in the registry 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.
Before assignment: All subjects enrolled were included in the trial. The data entered is for the overall study.
Overall Study
| Stage | TIV-adj | Flu-control | Non-flu Control |
|---|---|---|---|
| STARTED | 2019 | 1849 | 1034 |
| COMPLETED | 1895 | 1726 | 969 |
| NOT COMPLETED | 124 | 123 | 65 |
Reasons for not completing this period:
| Reason | TIV-adj | Flu-control | Non-flu Control |
|---|---|---|---|
| Lost to Follow-up | 37 | 34 | 16 |
| Withdrawal by Subject | 52 | 60 | 30 |
| Adverse Event | 8 | 5 | 1 |
| Inappropriate Enrollment | 1 | 3 | 0 |
| Protocol Deviation/violation | 20 | 19 | 15 |
| Unable to classify | 6 | 2 | 3 |
Analysis population for the primary outcome, as defined in the registry: The analysis was done on Safety set - All subjects in the exposed population who provided post-baseline safety data.
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 | TIV-adj | Flu-control | Non-flu Control | Total |
|---|---|---|---|---|---|
| Participants analysed | 2019 | 1849 | 1034 | 4902 | |
| Age, Continuous | Months | 31.9 (SD 19.8) | 32.6 (SD 20.1) | 32.2 (SD 19.8) | 32.2 (SD 19.9) |
| Sex: Female, Male: Female | Participants | 962 | 903 | 484 | 2349 |
| Sex: Female, Male: Male | Participants | 1057 | 946 | 550 | 2553 |
6. Primary Endpoint
The registry lists the primary outcome as Number of Subjects (Unprimed) 6 to <36 Months Age With Local and Systemic Reactions After Any Vaccination for All Seasons, Comparison of Adjuvanted Trivalent Influenza Vaccine (aTIV) and Flu Vaccine Control., measured over 7 days post-vaccination.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | Number of subjects |
| Endpoint classification | Binary Endpoint |
The primary endpoint is the number of unprimed subjects aged 6 to <36 months who experienced each local or systemic reaction within 7 days after any vaccination. The registry describes the comparison as aTIV versus flu-vaccine control, covering all seasons. It specifies a count of subjects, rather than a continuous measurement or a time-to-event quantity.
Counting subjects with reactions provides a direct description of how often each recorded reaction occurred in the defined safety population and observation period. Local and systemic reactions concern different experiences, so the endpoint is organized by reaction category rather than treated as one undifferentiated event. The count alone does not describe severity, duration, or the clinical importance of a reaction unless those features are separately defined and reported. Nor does the primary endpoint measure vaccine efficacy against influenza; virus-confirmed influenza appears among the secondary outcomes.
The registry record does not provide the category-specific results for this primary outcome. It therefore does not support a numerical account of how reaction counts compared between vaccine groups, or how precise those comparisons were. The endpoint definition is available, but its observed result is not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record establishes the question and analysis population for the primary endpoint, but it does not provide the actual category-specific counts or a statistical comparison for that endpoint. The primary outcome is the number of unprimed children aged 6 to <36 months experiencing each local or systemic reaction within 7 days after any vaccination. Without the reported counts by group, there is no basis in the registry record for describing the size or direction of a difference, or its uncertainty.
The adverse-event information separately lists six groups and gives numbers at risk and numbers affected by serious and other adverse events. For example, the TIV-adj 0.25 group lists 1177 at risk for serious events and 91 affected; it also lists 1177 at risk for other events and 1101 affected. The other groups have their own counts. These are descriptive safety figures, not the category-specific primary endpoint results. The registry record does not supply confidence intervals or an inferential comparison for those group figures, so they should not be treated as a test of the primary question.
The registry also lists serious adverse event terms with percentages, including Influenza at 7.3%, Gastroenteritis at 1.3%, Bronchopneumonia at 0.7%, Bronchitis at 0.7%, Concussion at 0.5%, and Gastroenteritis rotavirus at 0.5%. The listing does not establish an arm-specific comparison for each term, and the record does not include the underlying event counts alongside those percentages. The percentages therefore provide limited descriptive context and do not establish relative risk between groups.
Although efficacy and immunogenicity are part of the trial's stated aims, the primary endpoint described in the record is a safety outcome. Secondary outcomes include virus-confirmed influenza and influenza-like illness, but their results are not included in the registry entries. Consequently, no efficacy conclusion or comparison of influenza outcomes can be drawn from this record description. The appropriate reading is narrow: the registry describes a randomized trial with safety and influenza-related outcomes, while the results needed to quantify the primary safety comparison are not reported in the registry record.
Statistical precision cannot be judged for the primary comparison without effect estimates and uncertainty intervals. Counts by themselves can be informative descriptively, but they do not show how compatible the data are with a range of underlying group differences. No p-value, confidence interval, or adjusted estimate for the primary endpoint is reported in the registry record.
9. Statistical Methods Explained
The outcome is a count of subjects experiencing events. A count describes how many people in an analysis group had an event during the stated observation window. It is not automatically a rate: a rate ordinarily relates events to a specified amount of time, and the primary endpoint is defined as subjects with reactions within 7 days after vaccination. The registry gives the outcome unit as number of subjects.
What does a confidence interval communicate?
In general, a confidence interval gives a range of values compatible with the data and the statistical method used. It communicates uncertainty around an estimate; it does not say that the true value has a specified probability of lying in that particular interval. For a comparison of groups, an interval can help readers judge both the direction and precision of the estimated difference or ratio. No confidence interval for the primary outcome is reported in the registry record, so its precision cannot be assessed from the record.
Why distinguish the analysis population?
In general, a safety analysis often uses participants who received at least one study intervention and have relevant safety information. The registry describes this primary analysis population as exposed subjects who provided post-baseline safety data. That definition is narrower than simply counting everyone enrolled. It identifies who contributes to the analysis, but the record does not report the exact number included in the primary analysis or how participants without post-baseline safety data were handled.
The primary population is also defined by age and priming status: unprimed subjects aged 6 to <36 months. These restrictions matter because a result in one defined subgroup should not be assumed to describe every enrolled participant. The broader study included subjects aged 6 to <72 months, and several secondary outcomes cover broader or different age groups. The registry record does not provide a full account of how those outcome populations relate to each other.
What can group counts establish?
Counts of affected subjects can describe observed safety events in each listed group. To compare groups statistically, an analysis also needs a defined comparison measure and a method for representing uncertainty. General approaches for binary outcomes may compare proportions or model the probability of an event; the selected method depends on the protocol, outcome structure, and data. The registry record does not report the statistical method used for the primary reaction categories, so no particular method should be attributed to this trial.
When count data vary more than a simple model expects, over-dispersion can make standard errors too small if the model does not account for it. This is a general concern for count models, not a reported feature of this endpoint. The primary outcome counts subjects with reactions, and no model or dispersion assessment is reported in the registry record. It would therefore be inappropriate to infer that over-dispersion was present or that a particular adjustment was used.
How should the planning illustration be read?
General sample-size calculations ask how many participants may be needed to detect a specified effect under stated assumptions. Such calculations depend on choices such as the significance level, allocation, statistical approximation, and target effect. The planning illustration associated with this trial is described as using a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. It uses a stated fraction of the observed effect as the effect to detect. Those are assumptions for an illustration, not evidence that the trial was designed using those assumptions.
The illustration is based on an observed effect and is not the trial's own design justification. A planning sample size does not measure the probability that the completed trial detected an effect; that would be an observed-power interpretation and is not appropriate. The trial's sample-size justification is not reported in the registry record. Nor should planning values be read as observed participant counts: the record separately states enrollment of 4902, while the safety groups give their own numbers at risk.
The registry lists 21 outcome measures and 57 analyses. Multiple outcomes or comparisons can raise multiplicity concerns because examining many results may increase the chance of at least one apparently notable result. In general, planned outcome hierarchies, adjustment procedures, and prespecified contrasts help clarify interpretation. The multiplicity strategy and detailed statistical analysis plan are not reported in the registry record. No interim analysis plan is reported either, so it should not be inferred that interim monitoring or a particular stopping rule was used.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists 21 outcome measures and 57 analyses. With multiple outcomes, groups, age ranges, seasons, and comparisons, interpretation depends on which questions were prespecified and how the analysis handled repeated testing. In general, multiplicity adjustment can control the chance of false-positive findings across a defined family of tests, while a prespecified hierarchy can distinguish primary from supporting questions. The registry record does not report a multiplicity strategy or enough detail to identify the families of tests used. It is therefore not possible to say whether the reported analyses were adjusted or which comparisons were treated as confirmatory.
The record describes the primary analysis population as exposed subjects who provided post-baseline safety data. It does not report the number of participants excluded for missing safety data, the amount of missingness by group, or the method used to handle missing values. In general, missing data can affect estimates if participants with unavailable outcomes differ systematically from those with recorded outcomes. The extent and direction of any such effect cannot be assessed without details on missingness and analysis.
The registry does not report the full statistical analysis plan, the sample-size justification, or interim analyses. It also does not state whether the primary analysis followed a particular intention-to-treat or per-protocol definition. The named Safety set is the population description available for the primary endpoint; it should not be replaced with an assumed analysis population. These reporting gaps limit assessment of multiplicity control, missing-data assumptions, and the relation between the planned and completed analyses.
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 |
|---|---|---|---|
| TIV-adj_0.25 | 91 | 1177 | 7.7% |
| TIV-adj_0.5 | 31 | 835 | 3.7% |
| Flu-control_0.25 | 104 | 1069 | 9.7% |
| Flu-control_0.5 | 65 | 777 | 8.4% |
| Non-Flu-control (TBE/Men C Vaccine) | 65 | 607 | 10.7% |
| Non-Flu-control (TBE Vaccine) | 45 | 422 | 10.7% |
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 |
|---|---|
| TIV-adj_0.25 | 1101 of 1177 |
| TIV-adj_0.5 | 769 of 835 |
| Flu-control_0.25 | 989 of 1069 |
| Flu-control_0.5 | 686 of 777 |
| Non-Flu-control (TBE/Men C Vaccine) | 567 of 607 |
| Non-Flu-control (TBE Vaccine) | 375 of 422 |
Most frequent serious adverse event terms
| Event term | Organ system | TIV-adj_0.25 | TIV-adj_0.5 | Flu-control_0.25 | Flu-control_0.5 | Non-Flu-control (TBE/Men C Vaccine) | Non-Flu-control (TBE Vaccine) |
|---|---|---|---|---|---|---|---|
| Influenza | Infections and infestations | 12 of 1177 | 8 of 835 | 39 of 1069 | 40 of 777 | 33 of 607 | 31 of 422 |
| Gastroenteritis | Infections and infestations | 14 of 1177 | 1 of 835 | 13 of 1069 | 3 of 777 | 8 of 607 | 2 of 422 |
| Bronchitis | Infections and infestations | 8 of 1177 | 3 of 835 | 7 of 1069 | 0 of 777 | 3 of 607 | 1 of 422 |
| Pneumonia | Infections and infestations | 5 of 1177 | 2 of 835 | 5 of 1069 | 3 of 777 | 2 of 607 | 0 of 422 |
| Concussion | Injury, poisoning and procedural complications | 6 of 1177 | 2 of 835 | 1 of 1069 | 1 of 777 | 1 of 607 | 0 of 422 |
| Gastroenteritis rotavirus | Infections and infestations | 1 of 1177 | 1 of 835 | 5 of 1069 | 0 of 777 | 3 of 607 | 0 of 422 |
| Bronchopneumonia | Infections and infestations | 0 of 1177 | 1 of 835 | 2 of 1069 | 1 of 777 | 1 of 607 | 3 of 422 |
| Laryngitis | Infections and infestations | 1 of 1177 | 1 of 835 | 2 of 1069 | 1 of 777 | 3 of 607 | 0 of 422 |
| Pyrexia | General disorders | 2 of 1177 | 1 of 835 | 1 of 1069 | 2 of 777 | 0 of 607 | 1 of 422 |
| Febrile convulsion | Nervous system disorders | 2 of 1177 | 1 of 835 | 4 of 1069 | 0 of 777 | 0 of 607 | 0 of 422 |
Most frequent non-serious adverse event terms
| Event term | Organ system | TIV-adj_0.25 | TIV-adj_0.5 | Flu-control_0.25 | Flu-control_0.5 | Non-Flu-control (TBE/Men C Vaccine) | Non-Flu-control (TBE Vaccine) |
|---|---|---|---|---|---|---|---|
| Injection site pain | General disorders | 334 of 1177 | 478 of 835 | 250 of 1069 | 360 of 777 | 173 of 607 | 179 of 422 |
| Pyrexia | General disorders | 482 of 1177 | 299 of 835 | 412 of 1069 | 183 of 777 | 221 of 607 | 125 of 422 |
| Injection site erythema | General disorders | 423 of 1177 | 321 of 835 | 325 of 1069 | 268 of 777 | 240 of 607 | 128 of 422 |
| Upper respiratory tract infection | Infections and infestations | 362 of 1177 | 170 of 835 | 306 of 1069 | 156 of 777 | 174 of 607 | 85 of 422 |
| Cough | Respiratory, thoracic and mediastinal disorders | 246 of 1177 | 176 of 835 | 210 of 1069 | 166 of 777 | 119 of 607 | 97 of 422 |
| Injection site induration | General disorders | 214 of 1177 | 169 of 835 | 131 of 1069 | 152 of 777 | 154 of 607 | 79 of 422 |
| Otitis media | Infections and infestations | 250 of 1177 | 109 of 835 | 226 of 1069 | 110 of 777 | 130 of 607 | 62 of 422 |
| Somnolence | Nervous system disorders | 381 of 1177 | 1 of 835 | 315 of 1069 | 1 of 777 | 186 of 607 | 0 of 422 |
| Rhinitis | Infections and infestations | 260 of 1177 | 122 of 835 | 219 of 1069 | 97 of 777 | 123 of 607 | 57 of 422 |
| Crying | General disorders | 373 of 1177 | 5 of 835 | 325 of 1069 | 3 of 777 | 163 of 607 | 0 of 422 |
Serious events with the highest arm-level rate: influenza (7.3%), gastroenteritis (1.3%), bronchopneumonia (0.7%), bronchitis (0.7%), concussion (0.5%).
The registry lists serious and other adverse-event counts for six groups. Each group has a number at risk and a number affected for each event category. For example, TIV-adj 0.5 lists 835 at risk for serious events and 31 affected, and 835 at risk for other events and 769 affected. The other listed groups are TIV-adj 0.25, Flu-control 0.25, Flu-control 0.5, Non-Flu-control (TBE/Men C Vaccine), and Non-Flu-control (TBE Vaccine).
These figures are descriptive counts. The record does not provide a statistical comparison, uncertainty interval, or adjustment for differences between groups alongside them. They should not be treated as the primary local and systemic reaction endpoint, which concerns specific reactions within 7 days after vaccination in unprimed subjects aged 6 to <36 months. The record lists serious-event terms and percentages, but does not give arm-specific details for those terms in the registry record described. A death count is not reported in the registry record.
In general, serious adverse event counts describe events classified as serious under the study's reporting definitions; they do not by themselves establish causation. The registry record does not include enough detail to assess event timing, relatedness, severity by group, or the statistical precision of group differences. The safest reading is to keep the listed counts and percentages descriptive and avoid interpreting them as proof of a treatment effect.
12. What the Result Does, and Does Not, Mean
The record establishes that NCT00644059 was a randomized, controlled Phase III study of influenza vaccine strategies in healthy children aged 6 to <72 months, with a primary safety question in unprimed children aged 6 to <36 months. It specifies the reaction window as 7 days after any vaccination and identifies aTIV versus flu-vaccine control as the primary comparison. The registry also lists other vaccine controls and secondary outcomes concerned with safety and influenza-related illness.
What the record does not establish is the numerical result for each primary reaction category. Without those results, it is not possible to describe the direction or magnitude of the primary safety comparison, or how precisely it was estimated. The adverse-event group counts and serious-event term percentages are separate descriptive information; they do not fill in the missing primary endpoint results or provide an adjusted comparison.
The trial's stated aims include efficacy, safety, and immunogenicity, but the primary endpoint described in the record is safety. Secondary outcomes include virus-confirmed influenza and influenza-like illness. Their presence in the registry does not itself establish an outcome: results for those endpoints are not reported in the registry record. No conclusion about protection against influenza, immunogenicity, or comparative clinical benefit follows from the endpoint descriptions alone.
In general, a randomized design can support comparisons between assigned groups when the analysis, follow-up, and outcome reporting are sufficiently detailed. Randomization does not eliminate the need to examine missing data, analysis populations, outcome definitions, and uncertainty. Here, important statistical details—including the primary estimates, confidence intervals, and multiplicity procedures—are not reported in the registry record. Accordingly, the record supports a description of the trial's design and questions, but not a complete statistical interpretation of its effects.
13. Why This Trial Matters Statistically
This trial illustrates why endpoint definitions and analysis populations are central to reading clinical research. The overall study concerns healthy children aged 6 to <72 months, while the primary reaction endpoint concerns unprimed subjects aged 6 to <36 months. Keeping those populations distinct prevents a result for one group from being generalized automatically to another.
It also shows why safety outcomes should not be conflated with efficacy outcomes. The primary endpoint counts local and systemic reactions in a defined post-vaccination window. Virus-confirmed influenza and influenza-like illness appear among the secondary outcomes, but their inclusion as planned questions does not substitute for result estimates. Readers need endpoint-specific results to evaluate the corresponding question.
The record further demonstrates the limits of descriptive adverse-event counts. Counts can convey how many participants were affected in each group, and the record lists serious-event terms with percentages. However, comparative interpretation also depends on the analysis population, event definitions, uncertainty, and any statistical adjustment. Without those elements, descriptive figures do not determine whether observed group differences are precise or attributable to the intervention.
Finally, a planning illustration based on an observed effect is conceptually different from the original design justification. Sample-size planning depends on assumptions about the target effect and analysis. An illustration can help readers understand how planning changes under different target effects, but it is not evidence of the trial's planned power or a substitute for outcome estimates. The original sample-size justification and detailed analysis plan are not reported in the registry record.
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 principal limitation for statistical interpretation is that the registry record does not report category-specific results for the primary endpoint. It defines reactions, population, comparison, and observation period, but does not give the counts or estimates needed to quantify the comparison. Confidence intervals and p-values for that primary question are also not reported in the registry record.
The record lists serious and other adverse-event counts by group and serious-event terms with percentages, but does not provide the detailed context needed for an adjusted comparison. The listed term percentages are not accompanied by arm-specific event counts in the registry record described. A death count is not reported in the registry record. The group counts therefore should not be treated as a complete account of comparative safety.
The study includes multiple age ranges, vaccine groups, outcomes, and analyses. The registry lists 21 outcome measures and 57 analyses, but does not report the multiplicity strategy or full analysis plan. It also does not report missing-data counts or handling, interim analyses, or the sample-size justification. These gaps prevent assessment of whether the recorded analyses followed prespecified procedures and how missing information may have affected the findings.
The registry states an overall enrollment of 4902, while the adverse-event data have group-specific numbers at risk. The primary analysis population is described as exposed subjects with post-baseline safety data, but its total size is not reported. The record also does not provide enough detail to reconstruct dosing and assignment sequences across all participants. These limitations constrain interpretation to the trial description and the particular descriptive figures that are explicitly listed.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Study to Evaluate the Efficacy, Safety and Immunogenicity of Influenza Vaccine in Healthy Subjects (Aged 6 to <72 Months) Versus Control Vaccines — NCT00644059.
- Registry record last updated 2015-09-18; status last verified 2015-08.
- Results first posted 2014-10-15.
- 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.
Continue through the Clinical Biostats statistical pathway
Use this trial's endpoint as a starting point for deeper study of effect measures, confidence intervals, and sample-size planning.
18. Record Summary
NCT00644059 is a completed, randomized, observer-blind, controlled, multicenter Phase III trial with parallel groups and enrollment of 4902. It studied an adjuvanted trivalent inactivated subunit influenza vaccine against flu-vaccine and non-influenza vaccine controls in healthy children aged 6 to <72 months.
The primary endpoint counts unprimed subjects aged 6 to <36 months with local or systemic reactions within 7 days after any vaccination, comparing aTIV with flu-vaccine control across all seasons. The registry describes the Safety set as exposed subjects who provided post-baseline safety data. It lists 21 outcome measures, 57 analyses, group-level adverse-event counts, and serious-event terms with percentages.
Category-specific primary results, confidence intervals, the detailed statistical analysis plan, multiplicity procedures, missing-data methods, and sample-size justification are not reported in the registry record. The record therefore supports description of the design and outcome questions, but not a quantitative conclusion about the primary comparison.