This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for Safety of and Immune Response to a Meningitis Vaccine in HIV-Infected Children and Youth (NCT00459316), a randomized phase 1, phase 2 study. The primary outcome is Number of Immunogenic Responders, With Response Defined as a 4-fold or Greater Increase in Serum Bactericidal Antibody Titers From Study Entry to Week 28 After 2 Doses of MCV-4..
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00459316 |
| Phase | Phase 1, Phase 2 |
| Condition | HIV Infections, Meningitis |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 384 |
| Arms in the primary outcome | n/a |
| Lead sponsor | National Institute of Allergy and Infectious Diseases (NIAID) |
| Results posted | Yes |
2. Clinical Question
Population
The study enrolled HIV-infected children and youth, with groups distinguished by age and CD4% at screening. The registry describes Group 1 participants as having CD4% at screening of 15% to 25% or at least 25%, Group 2 as having CD4% below 15%, and Group 3 as younger participants with CD4% at least 25%. The precise age wording for Group 1 and Group 2 is not fully clear in the registry record.
Intervention
The intervention was quadrivalent meningococcal conjugate vaccine, or MCV4. Participants received a dose at study entry. Eligible participants could receive further doses according to group and study step; the primary immune-response measure concerns participants who received 2 doses.
Comparator
The study was randomized, but the registry record does not describe one uniform comparison across all participants. In Group 1, eligible participants were randomized at week 24, with Group 1B receiving a second dose then. The specific comparator group and allocation details for the primary endpoint are not reported in the registry record.
Primary question
The primary endpoint counts participants with a 4-fold or greater increase in serum bactericidal antibody titers from study entry to week 28 after 2 MCV4 doses. It assesses immune response for the vaccine's four serogroups in the analyzed participants. The registry record does not report the response counts or proportions by group.
3. Trial Design
NCT00459316 was a Phase I/II, randomized, open-label study using a parallel-group model. Its stated purpose was to assess the safety and immune response to preventive meningitis vaccination in HIV-infected youth. The registry lists an enrollment of 384 and identifies the National Institute of Allergy and Infectious Diseases (NIAID) as sponsor. The study started in 2007-06, reached primary completion in 2013-03, and has a completed status.
The vaccine was quadrivalent meningococcal conjugate vaccine. The group descriptions organize participants using age and CD4% at screening. All described groups received vaccine at study entry. In Group 1, eligible participants were randomized at week 24, and Group 1B received a second dose at that time. Group 2 and Group 3 descriptions also refer to further vaccination among eligible participants at week 24 and 3 years. The exact allocation sequence, the number assigned to each randomized arm, and the criteria for eligibility for later doses are not reported in the registry record.
The registry also describes an open-label immunogenicity study of a booster dose in previously immunized HIV-infected children and youth. This makes the record broader than a single, simple comparison of vaccination against no vaccination: the schedule and analysis population depend on study group and step. The primary endpoint specifically concerns participants who received 2 doses and had antibody data at both study entry and week 28. The record does not report a placebo or untreated control group for that endpoint.
Because masking was listed as none, participants and study personnel were not masked according to the registry design entry. The consequences of that design feature depend on the outcome: laboratory antibody measurements may be less susceptible to expectations than outcomes based on subjective reporting, while safety reporting and clinical decisions can be more open to awareness of treatment. Details of laboratory masking, outcome adjudication, and the exact randomization procedure 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.
Steps 1 & 2
| Stage | Group 1: CD4%≥15, Age ≤11 to <25 | Group 2: CD4%<15, Age ≤11 to <25 | Group 3: Age ≥2 to <11, CD4%≥25 |
|---|---|---|---|
| STARTED | 280 | 39 | 59 |
| COMPLETED | 259 | 32 | 57 |
| NOT COMPLETED | 21 | 7 | 2 |
Reasons for not completing this period:
| Reason | Group 1: CD4%≥15, Age ≤11 to <25 | Group 2: CD4%<15, Age ≤11 to <25 | Group 3: Age ≥2 to <11, CD4%≥25 |
|---|---|---|---|
| Other eligibility failure | 1 | 1 | 0 |
| Death | 1 | 1 | 0 |
| Not able to get to clinic | 7 | 4 | 0 |
| Withdrawal by Subject | 6 | 1 | 0 |
| Not willing to adhere to regulations | 1 | 0 | 0 |
| Lost to Follow-up | 5 | 0 | 2 |
Step 3
| Stage | Group 1: CD4%≥15, Age ≤11 to <25 | Group 2: CD4%<15, Age ≤11 to <25 | Group 3: Age ≥2 to <11, CD4%≥25 |
|---|---|---|---|
| STARTED | 152 | 0 | 40 |
| COMPLETED | 149 | 0 | 39 |
| NOT COMPLETED | 3 | 0 | 1 |
Reasons for not completing this period:
| Reason | Group 1: CD4%≥15, Age ≤11 to <25 | Group 2: CD4%<15, Age ≤11 to <25 | Group 3: Age ≥2 to <11, CD4%≥25 |
|---|---|---|---|
| Withdrawal by Subject | 3 | 0 | 1 |
Analysis population for the primary outcome, as defined in the registry: This outcome only includes participants who received 2 doses and had antibody data from both entry and Week 28.The number of participants analyzed for Group 1 (15\<CD4%\<25), Group 1 (CD4%≥25), Group 2, Group 3 are respectively: serogroup A: 49, 63, 20, 49 serogroup C: 47, 65, 18, 49 serogroup W-135: 47, 66, 19, 49 serogroup Y: 49, 66, 19, 49
5. Baseline Characteristics
The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.
Population: All participants who started study treatment.
| Characteristic | Unit | Group 1 (15<CD4%<25) | Group 1 (CD4%≥25) | Group 2 | Group 3 | Total |
|---|---|---|---|---|---|---|
| Participants analysed | 127 | 153 | 39 | 59 | 378 | |
| Age, Continuous | years | 18 (11 to 24) | 16 (11 to 24) | 20 (14 to 24) | 6 (2 to 10) | 16 (2 to 24) |
| Sex: Female, Male: Female | Participants | 44 | 70 | 16 | 31 | 161 |
| Sex: Female, Male: Male | Participants | 83 | 83 | 23 | 28 | 217 |
| Race: Asian | participants | 1 | 1 | 0 | 2 | 4 |
| Race: Native Hawaiian or other Pacific islander | participants | 1 | 0 | 0 | 1 | 2 |
| Race: Black or African American | participants | 72 | 69 | 22 | 34 | 197 |
| Race: White | participants | 47 | 75 | 14 | 21 | 157 |
| Race: American Indian | participants | 2 | 3 | 0 | 0 | 5 |
| Race: More than One race | participants | 0 | 3 | 2 | 0 | 5 |
| Race: Unknown | participants | 4 | 2 | 1 | 1 | 8 |
| Ethnicity: Hispanic or Latino | participants | 44 | 61 | 16 | 18 | 139 |
| Ethnicity: Not Hispanic or Latino | participants | 83 | 89 | 23 | 40 | 235 |
| Ethnicity: Unknown | participants | 0 | 3 | 0 | 1 | 4 |
| Screening CD4% | percent | 20.0 (14.0 to 24.9) | 33.0 (25.0 to 53.1) | 8.5 (1.0 to 14.0) | 36.0 (25.0 to 56.0) | 27.9 (1.0 to 56.0) |
| Entry plasma HIV RNA viral load, copies/mL: <400 copies/mL | participants | 35 | 83 | 3 | 43 | 164 |
| Entry plasma HIV RNA viral load, copies/mL: ≥ 400 copies/mL | participants | 92 | 70 | 36 | 16 | 214 |
| CDC Classification at Study Entry: C | participants | 28 | 37 | 11 | 8 | 84 |
| CDC Classification at Study Entry: Not C | participants | 99 | 116 | 28 | 51 | 294 |
| Antiretroviral (ARV) Treatment at Entry: HAART with PI | participants | 70 | 81 | 22 | 38 | 211 |
| Antiretroviral (ARV) Treatment at Entry: HAART with NNRTI (no PI) | participants | 14 | 34 | 3 | 14 | 65 |
| Antiretroviral (ARV) Treatment at Entry: Other ARV | participants | 6 | 8 | 1 | 1 | 16 |
| Antiretroviral (ARV) Treatment at Entry: No ARV | participants | 37 | 30 | 13 | 6 | 86 |
6. Primary Endpoint
The registry lists the primary outcome as Number of Immunogenic Responders, With Response Defined as a 4-fold or Greater Increase in Serum Bactericidal Antibody Titers From Study Entry to Week 28 After 2 Doses of MCV-4., measured over Study entry and Week 28.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint counts immunogenic responders after 2 doses of MCV4. A responder was defined as a participant with a 4-fold or greater increase in serum bactericidal antibody titers from study entry to week 28. Titers were measured for each of the four serogroups included in the vaccine. The comparison is therefore a change from each participant's entry measurement, not simply a final antibody level.
General: a fold-rise criterion describes the size of change relative to a starting measurement. It can make an immune response definition interpretable across participants whose entry antibody levels differ, though the resulting responder count depends on the chosen threshold and on having measurements at both time points. The endpoint is an immunogenicity measure: it records an antibody response, not a direct count of meningitis infections or evidence about clinical protection.
The primary analysis population was restricted to participants who received 2 doses and had antibody data at both study entry and week 28. The registry lists analyzed group counts for serogroup A as 49, 63, 20, and 49, and for serogroup C as 47, 65, 18, and 49, across the stated groups. The corresponding listing for another serogroup is incomplete in the registry record. Response counts, proportions, and uncertainty estimates are not reported in the registry record, so the magnitude and precision of the immune response cannot be described from these registry entries.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies a primary immunogenicity endpoint, but it does not include the observed responder counts for that endpoint. It therefore does not permit a numerical description of how many analyzed participants met the 4-fold or greater response definition, nor a comparison of response between groups. No confidence intervals or significance tests for the primary endpoint are reported in the registry record. Without those results, the strength and precision of any group differences cannot be assessed.
The endpoint is based on antibody measurements at study entry and week 28 among participants who received 2 doses and had measurements at both times. That is a selected analysis population, rather than a count of everyone enrolled. The registry lists group-specific analyzed counts for serogroup A and serogroup C, but does not provide the corresponding responder counts. It also does not fully report the analyzed counts for all four serogroups. These gaps prevent a complete reading of the primary immune-response result.
The safety information includes serious adverse event counts for four groups: 4 of 127 in Group 1 (15<CD4%≤25), 5 of 153 in Group 1 (CD4%≥25), 5 of 39 in Group 2, and 2 of 59 in Group 3. These are descriptive counts, and the registry also reports non-serious adverse event counts. They should not be interpreted as a comparative test of safety: the registry record does not provide an adjusted analysis, uncertainty intervals, or a clearly specified statistical comparison for these figures. Group sizes and participant characteristics differ, and the record's group definitions and dose schedules are not interchangeable.
Serious adverse event terms listed in the record include Candida sepsis, migraine, foetal death, nephrolithiasis, and rash, each at 2.6%, and pneumonia at 1.7%. The denominator and grouping basis for these term percentages are not reported in the registry record, so they should not be treated as rates for a particular study group. The listing also does not establish that an event was caused by vaccination.
Overall, the registry entries describe the design, endpoint definition, and selected safety counts, but not the primary outcome result. They support a careful account of what was measured and who was analyzed, not a conclusion about the size of the antibody response or comparative safety.
9. Statistical Methods Explained
General: a randomized design assigns participants by chance to study groups, which can reduce systematic differences between groups at the time of assignment. Randomization does not guarantee that groups are identical, especially in smaller subgroups, and it does not resolve questions about missing measurements or later eligibility. This study is listed as randomized, but the registry record does not report the randomization sequence, allocation concealment, or the detailed comparison used for the primary endpoint.
What does the responder definition measure?
The endpoint classifies participants using whether serum bactericidal antibody titers increased by 4-fold or greater from study entry to week 28 after 2 MCV4 doses. Such a binary endpoint turns a continuous antibody measurement into a responder or non-responder classification. This can simplify interpretation, but it also discards information about how far a participant's change lies above or below the threshold. General: results near a classification threshold may be sensitive to measurement variability, while a continuous analysis can preserve more of the observed variation. The registry record does not report whether a continuous antibody analysis was also performed.
The endpoint is assessed separately across vaccine serogroups. The registry describes titers for each of the four serogroups, and the analysis population requires measurements at both time points. A response result for one serogroup does not automatically summarize response for the others. The primary outcome result by serogroup is not reported in the registry record, and the record does not identify a single pooled estimate across serogroups.
How should a group comparison be interpreted?
General: a comparison of responder counts may be expressed as a difference in proportions, a relative measure, or a model-based estimate. Each conveys a different aspect of the contrast. An uncertainty interval describes the range of effect estimates compatible with the observed data under the method's assumptions; it does not guarantee that the true effect lies within the interval. A p-value, when reported, addresses compatibility with a specified null model and is not a measure of clinical importance. No primary endpoint effect estimates, confidence intervals, or p-values are reported in the registry record, so none can be interpreted for this study.
The sample-size assumptions listed for planning illustrations use a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. They specify an effect to detect as a stated fraction of the observed effect. These are planning illustrations based on the observed effect, not the trial's own design justification and not observed power. The numerical planning outputs and the trial's sample-size justification are not reported in the registry record. General: sample-size planning estimates the amount of information needed under chosen assumptions; it does not establish that a study had adequate precision after enrollment or missing data.
Why do group structure and eligibility matter?
The registry describes a parallel design but also several cohorts, varying CD4% and age criteria, eligibility for later doses, and an additional booster study. Group 1 had randomization at week 24 among eligible participants, whereas the Group 2 and Group 3 descriptions refer to later doses for eligible participants. The full statistical plan for handling these pathways is not reported in the registry record. A comparison that combines groups or schedules could therefore answer a different question from a comparison within a randomized subset.
The number analyzed for the primary endpoint is not the enrollment count: eligibility required 2 doses and antibody data at both entry and week 28. General: restricting analysis to participants with complete measurements can introduce bias if completion is related to health status, immune response, or treatment experience. The record does not describe missing-data methods or give a full account of reasons for absent measurements. It also does not report whether analysis followed randomized assignment regardless of later dosing.
How should safety counts be handled?
The registry lists participants with serious adverse events and participants with other adverse events in each group. These are event-participant counts, not a modeled comparison. General: counts depend on the group denominator and observation period, and direct comparisons can be misleading when follow-up or exposure differs. The record does not provide a statistical test or adjusted safety estimate for the displayed group counts. The listed serious event terms and percentages also lack a reported denominator basis in the registry record. No causal attribution should be inferred from a term appearing in an adverse-event listing.
10. Multiplicity, Missing Data and Analysis Populations
The primary immune-response endpoint is assessed across the vaccine's four serogroups, and the registry record lists 15 outcome measures and 2 analyses. Multiple outcomes or repeated comparisons can increase the chance of a false-positive finding if each is tested separately without a suitable analysis plan. General: multiplicity methods can control that risk or distinguish a primary confirmatory question from exploratory analyses. The registry record does not report whether multiplicity adjustments were used, which outcomes were designated for adjustment, or how the analyses were prioritized.
The primary endpoint includes only participants who received 2 doses and had antibody measurements at both study entry and week 28. This complete-measurement requirement means that participants without one of those measurements are not included in the stated endpoint population. The record does not report how many otherwise eligible participants lacked measurements, why data were missing, or whether any imputation or sensitivity analysis was conducted. Missing-data methods are not reported in the registry record.
The analysis population is therefore only partly specified: the record names the dose and measurement requirements and gives some group counts by serogroup, but the full analysis set definition is not reported. It is also not reported in the registry record whether participants were analyzed according to randomized assignment, according to doses received, or using another population definition. These details matter because excluding participants after randomization can affect comparability between groups.
The registry record does not report an interim-analysis plan, stopping rules, or the statistical analysis plan. This absence does not establish that such procedures were or were not used; their status is not reported in the registry record.
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 |
|---|---|---|---|
| Group 1 (15<CD4%≤25) | 4 | 127 | 3.1% |
| Group 1 (CD4%≥25) | 5 | 153 | 3.3% |
| Group 2 | 5 | 39 | 12.8% |
| Group 3 | 2 | 59 | 3.4% |
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 |
|---|---|
| Group 1 (15<CD4%≤25) | 94 of 127 |
| Group 1 (CD4%≥25) | 113 of 153 |
| Group 2 | 33 of 39 |
| Group 3 | 47 of 59 |
Most frequent serious adverse event terms
| Event term | Organ system | Group 1 (15<CD4%≤25) | Group 1 (CD4%≥25) | Group 2 | Group 3 |
|---|---|---|---|---|---|
| Abortion spontaneous | Pregnancy, puerperium and perinatal conditions | 1 of 127 | 2 of 153 | 0 of 39 | 0 of 59 |
| Hepatitis | Hepatobiliary disorders | 1 of 127 | 0 of 153 | 0 of 39 | 0 of 59 |
| Candida sepsis | Infections and infestations | 0 of 127 | 0 of 153 | 1 of 39 | 0 of 59 |
| Pelvic inflammatory disease | Infections and infestations | 1 of 127 | 0 of 153 | 0 of 39 | 0 of 59 |
| Pneumonia | Infections and infestations | 0 of 127 | 0 of 153 | 0 of 39 | 1 of 59 |
| Overdose | Injury, poisoning and procedural complications | 0 of 127 | 1 of 153 | 0 of 39 | 0 of 59 |
| Hyperglycaemia | Metabolism and nutrition disorders | 0 of 127 | 1 of 153 | 0 of 39 | 0 of 59 |
| Muscular weakness | Musculoskeletal and connective tissue disorders | 0 of 127 | 0 of 153 | 0 of 39 | 1 of 59 |
| Headache | Nervous system disorders | 0 of 127 | 1 of 153 | 0 of 39 | 0 of 59 |
| Migraine | Nervous system disorders | 0 of 127 | 0 of 153 | 1 of 39 | 0 of 59 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Group 1 (15<CD4%≤25) | Group 1 (CD4%≥25) | Group 2 | Group 3 |
|---|---|---|---|---|---|
| Neutrophil count decreased | Investigations | 31 of 127 | 36 of 153 | 12 of 39 | 19 of 59 |
| Cough | Respiratory, thoracic and mediastinal disorders | 20 of 127 | 23 of 153 | 3 of 39 | 12 of 59 |
| Pyrexia | General disorders | 13 of 127 | 11 of 153 | 6 of 39 | 12 of 59 |
| Oropharyngeal pain | Respiratory, thoracic and mediastinal disorders | 12 of 127 | 13 of 153 | 7 of 39 | 7 of 59 |
| Abdominal pain | Gastrointestinal disorders | 11 of 127 | 14 of 153 | 7 of 39 | 3 of 59 |
| Headache | Nervous system disorders | 14 of 127 | 13 of 153 | 3 of 39 | 5 of 59 |
| Adverse event | General disorders | 14 of 127 | 12 of 153 | 0 of 39 | 8 of 59 |
| Nasal congestion | Respiratory, thoracic and mediastinal disorders | 6 of 127 | 13 of 153 | 1 of 39 | 7 of 59 |
| Vomiting | Gastrointestinal disorders | 7 of 127 | 9 of 153 | 4 of 39 | 4 of 59 |
| Ear pain | Ear and labyrinth disorders | 10 of 127 | 7 of 153 | 2 of 39 | 4 of 59 |
Serious events with the highest arm-level rate: candida sepsis (2.6%), migraine (2.6%), foetal death (2.6%), nephrolithiasis (2.6%), rash (2.6%).
The serious adverse event figures are reported as participants with an event and the number at risk in each group: 4 of 127 in Group 1 (15<CD4%≤25), 5 of 153 in Group 1 (CD4%≥25), 5 of 39 in Group 2, and 2 of 59 in Group 3. The registry also lists other adverse event counts of 94 of 127, 113 of 153, 33 of 39, and 47 of 59, respectively. These are descriptive counts; no group comparison or uncertainty estimate is reported in the registry record.
The record lists serious adverse event terms and percentages, including Candida sepsis, migraine, foetal death, nephrolithiasis, and rash at 2.6% each, and pneumonia at 1.7%. The denominator and the way these terms relate to the groups are not reported in the registry record. The terms should therefore be read as registry-listed events, not as group-specific risks or evidence of causation. Death counts are not reported in the registry record. Differences in group definitions, eligibility, and dose schedules further limit direct comparison of the counts.
12. What the Result Does, and Does Not, Mean
The study addresses immune response to MCV4 in HIV-infected children and youth, with safety also assessed. Its primary endpoint uses a defined antibody rise from study entry to week 28 after 2 doses. This makes the intended measure clear: it is a laboratory-based immunogenicity outcome, not a direct measure of meningitis cases or of clinical protection.
The registry record does not report the primary responder counts, response proportions, or uncertainty estimates. As a result, the registry entries do not establish the size or precision of the immune response, nor whether responses differed between groups. The listed numbers analyzed for some serogroups describe the size of the analysis populations, not the number who met the responder definition.
The safety counts document reported serious and other adverse events in the study groups. They are not, by themselves, proof that an event was caused by the vaccine, and they do not support a statistical comparison between schedules without further information on follow-up, exposure, and analysis. The serious-event term percentages lack a reported denominator basis, which limits their interpretation.
General: immunogenicity findings can inform understanding of antibody response, but they are not interchangeable with clinical outcomes. A study can measure whether an immune marker changes without directly estimating infection prevention, disease severity, or long-term protection. Those clinical outcomes are not reported as results in the registry record. The study's open-label design, group-specific schedules, and eligibility for later doses also mean that a result from one group should not automatically be generalized to every enrolled participant.
The most defensible reading is therefore bounded: the registry describes the trial structure, defines the antibody-response outcome, and lists safety counts, but it does not provide the primary result needed to judge the observed immune response. No treatment recommendation or conclusion about vaccine effectiveness follows from these registry entries alone.
13. Why This Trial Matters Statistically
This trial is statistically notable because it combines a randomized, parallel design with several participant groups defined by age and CD4% at screening, differing eligibility for subsequent doses, and an open-label booster component. Those features make the target comparison important: a result among a subset randomized at week 24 would not necessarily answer the same question as an overall analysis across all groups and schedules.
The primary outcome also highlights the distinction between a laboratory endpoint and a clinical outcome. A 4-fold or greater antibody-titer increase is a specified way to classify immune response, but it is not itself a count of meningitis infections. Statistical interpretation must remain tied to the endpoint actually measured.
The analysis population requires receipt of 2 doses and antibody data at both study entry and week 28. This illustrates why denominators and missing-data handling matter: an outcome can be calculated only for participants meeting the stated criteria, and the record does not fully explain who was excluded or why. The partial reporting of analyzed group counts, without responder counts, makes that distinction especially important.
The safety information likewise illustrates the difference between descriptive reporting and comparative inference. Counts by group provide context, but without a clearly reported comparison, exposure details, or uncertainty estimates, they cannot establish whether observed differences exceed chance variation or reflect differences in group composition.
Finally, the registry's lack of primary outcome estimates, multiplicity details, and a complete analysis description limits reproducibility and critical appraisal. These are not reasons to infer a particular result. They identify the specific information a reader would need to understand the estimate, its precision, and the scope of the conclusion.
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 interpreting efficacy-related results is that the primary responder counts and estimates are not reported in the registry record. The endpoint definition is available, but the observed response by group and serogroup, along with confidence intervals or test results, is not. The record's analyzed counts for serogroup W-13 are incomplete, so the listed analysis population cannot be fully described across all four serogroups.
The primary analysis population excludes participants who did not receive 2 doses or lacked antibody data at either required time point. The record does not report how many participants were excluded for these reasons, why measurements were missing, or whether missingness was addressed through imputation or sensitivity analyses. It also does not report whether analysis was based on randomized assignment or treatment received.
The design information is incomplete for understanding the causal comparison. Although randomization is listed, details of sequence generation, allocation concealment, arm sizes, and the primary endpoint's comparator are not reported in the registry record. The open-label design may also matter for reporting and handling safety events. The effect of that feature cannot be quantified from the registry entries.
The safety counts lack reported uncertainty estimates and a specified comparative analysis. The denominator basis for the serious-event term percentages is not reported. Follow-up details specific to these adverse event counts and an assessment of attribution are also not reported in the registry record. Consequently, the counts should remain descriptive.
Other limitations include the absence of reported multiplicity procedures, interim-analysis details, and a full statistical analysis plan. The sample-size justification is not reported in the registry record; planning assumptions described for illustrations should not be mistaken for the trial's own design rationale.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Safety of and Immune Response to a Meningitis Vaccine in HIV-Infected Children and Youth — NCT00459316.
- Registry record last updated 2021-11-03; status last verified 2021-10.
- Results first posted 2014-05-12.
- 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
NCT00459316 was a completed, randomized, open-label Phase I/II parallel study sponsored by the National Institute of Allergy and Infectious Diseases (NIAID). It enrolled 384 participants and evaluated quadrivalent meningococcal conjugate vaccine in HIV-infected children and youth. The study started in 2007-06 and reached primary completion in 2013-03.
The primary endpoint counted participants with a 4-fold or greater increase in serum bactericidal antibody titers from study entry to week 28 after 2 doses. The analysis required antibody data at both time points. The registry record does not report the primary responder counts or estimates. It reports serious adverse event counts by group and lists several serious-event terms, but does not report a comparative safety analysis or the denominator basis for the term percentages. Missing-data procedures, multiplicity handling, and the full statistical analysis plan are not reported in the registry record.