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 and Immunogenicity of 13-Valent Pneumococcal Conjugate Vaccine (13vPnC) in HIV-Infected Subjects 6 Years of Age or Older Who Are Naive to Pneumococcal Vaccine (NCT00962780), a na phase 3 study. The primary outcome is Geometric Mean Fold Rise (GMFR) for Serotype-Specific Pneumococcal Immunoglobulin G (IgG) Antibody From 1 Month After 13vPnC Dose 2 to 1 Month After 13vPnC Dose 3 in All Participants.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00962780 |
| Phase | Phase 3 |
| Condition | HIV Infections, Pneumococcal Infections |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 303 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Pfizer |
| Results posted | Yes |
2. Clinical Question
Population
HIV-infected participants aged 6 years or older who had not previously been immunized with a pneumococcal vaccine. The primary endpoint used an evaluable immunogenicity population: participants had to receive vaccination as assigned, have blood drawn within specified time frames, have at least 1 valid, determinate assay result, and have no major protocol violation.
Intervention
The vaccination schedule comprised 3 doses of 13-valent pneumococcal conjugate vaccine (13vPnC) and 1 dose of 23-valent pneumococcal polysaccharide vaccine (23vPS), with each dose given approximately 1 month apart.
Comparator
There was no separate comparison group. The trial is classified as single-group, with allocation recorded as NA. The primary endpoint compares immune measurements after 13vPnC Dose 2 and Dose 3 within the vaccination schedule; it is not a randomized comparison of treatments.
Primary question
Among all participants evaluable for the endpoint, what was the geometric mean fold rise in serotype-specific pneumococcal IgG antibody from 1 month after 13vPnC Dose 2 to 1 month after 13vPnC Dose 3, across the 13 specified serotypes?
This question concerns change in measured antibody concentration over two assessment times. It does not compare the schedule with no vaccination, another vaccine schedule, or a concurrently assigned control group. The registry record describes the endpoint and its analysis population, but a numerical estimate and confidence interval are not reported in the registry record. Therefore, the magnitude and precision of the immune-response change cannot be assessed from the registry record.
3. Trial Design
This was a Phase 3, open-label, single-group trial. The registry lists enrollment as 303 and status as completed. The recorded study start was 2010-03, and primary completion was 2013-04. The sponsor was Pfizer. The study concerned HIV infections and pneumococcal infections.
All participants were to receive 3 doses of 13vPnC and 1 dose of 23vPS, each dose given approximately 1 month apart. The registry also lists blood draws as procedures. Because the study was open-label and had no separate randomized arm, there was no blinded or concurrent control comparison described in the record. The primary immune-response comparison was between measurements taken 1 month after 13vPnC Dose 2 and 1 month after 13vPnC Dose 3.
The primary outcome was a geometric mean fold rise (GMFR) in serotype-specific pneumococcal IgG antibody among all participants evaluable for that measure. Secondary outcomes included IgG geometric mean concentrations, opsonophagocytic activity geometric mean titers, and fold rises in IgG or opsonophagocytic activity. These outcomes were described across pediatric, adult, and all-participant groups, as applicable. The registry lists 19 outcome measures and 0 analyses.
The design can describe immune measurements and adverse events recorded during the schedule, but a single-group study does not provide a randomized estimate of how those measurements or events would differ under another treatment. Further details about the planned statistical analysis, including any prespecified comparisons beyond the endpoint descriptions, 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.
Overall Study
| Stage | 13vPnC, 23vPS (Pediatric Participants) | 13vPnC, 23vPS (Adult Participants) |
|---|---|---|
| STARTED | 151 | 152 |
| Vaccinated 13vPnC Dose 1 | 150 | 151 |
| Vaccinated 13vPnC Dose 2 | 145 | 145 |
| Vaccinated 13vPnC Dose 3 | 144 | 142 |
| Vaccinated 23vPS Dose | 143 | 139 |
| COMPLETED | 141 | 138 |
| NOT COMPLETED | 10 | 14 |
Reasons for not completing this period:
| Reason | 13vPnC, 23vPS (Pediatric Participants) | 13vPnC, 23vPS (Adult Participants) |
|---|---|---|
| Death | 0 | 1 |
| Protocol Violation | 9 | 4 |
| Withdrawal by Subject | 1 | 8 |
| Other | 0 | 1 |
Analysis population for the primary outcome, as defined in the registry: Evaluable immunogenicity population:eligible participants who received vaccination as assigned;had blood drawn within pre-specified time-frames;had at least 1 valid, determinate assay result; had no major protocol violation. N (number of participants analyzed)=participants evaluable for this measure, n=participants evaluable for specified serotype.
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: Safety population included all enrolled participants who received at least 1 dose of investigational product.
| Characteristic | Unit | 13vPnC, 23vPS (Pediatric Participants) | 13vPnC, 23vPS (Adult Participants) | Total |
|---|---|---|---|---|
| Participants analysed | 150 | 151 | 301 | |
| Age, Continuous | years | 10.3 (SD 3.04) | 41.2 (SD 8.45) | 25.8 (SD 16.72) |
| Sex: Female, Male: Female | Participants | 76 | 88 | 164 |
| Sex: Female, Male: Male | Participants | 74 | 63 | 137 |
6. Primary Endpoint
The registry lists the primary outcome as Geometric Mean Fold Rise (GMFR) for Serotype-Specific Pneumococcal Immunoglobulin G (IgG) Antibody From 1 Month After 13vPnC Dose 2 to 1 Month After 13vPnC Dose 3 in All Participants, measured over 1 month after 13vPnC Dose 2, 1 month after 13vPnC Dose 3.
| Element | Registry entry |
|---|---|
| Result type | Geometric Mean |
| Measure of spread | 95% Confidence Interval |
| Unit | fold rise |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is the geometric mean fold rise in pneumococcal immunoglobulin G (IgG) antibody from 1 month after 13vPnC Dose 2 to 1 month after 13vPnC Dose 3. It covers 13 pneumococcal serotypes: 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F, and 23F. The analysis was to use participants with data from both blood draws who met the evaluable-population criteria.
In general, a fold rise expresses the ratio between a later measurement and an earlier measurement. A geometric mean summarizes such ratios on a logarithmic scale and then returns them to the original scale. This approach is often used for antibody measurements because their distributions can be right-skewed. The endpoint therefore summarizes the average relative change, rather than the average absolute change in antibody concentration.
The registry states that the assay results were log-transformed and that the confidence interval was obtained by transforming back a Student t-based interval for the mean logarithm of the fold rise. The endpoint is a laboratory immune-response measure; it is not, by itself, a direct measure of clinical illness or protection. A numerical GMFR estimate and its confidence interval are not reported in the registry record, so the observed direction, size, and precision of the change cannot be described.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record provides the trial design, endpoint definition, analysis-population criteria, and safety summaries, but it does not provide numerical results for the primary endpoint. It lists 19 outcome measures and 0 analyses. Consequently, there is no posted GMFR estimate or confidence interval to interpret for the change in IgG antibody between the post-Dose 2 and post-Dose 3 assessment times.
A confidence interval would ordinarily communicate both the estimated fold rise and the uncertainty around that estimate. A narrower interval generally indicates greater statistical precision, while a wider interval indicates less precision. Here, neither an estimate nor an interval is reported in the registry record, so the precision of the primary result cannot be evaluated. It is also not possible to determine from the record whether the result was above, below, or near a value considered meaningful for a particular scientific or clinical purpose.
The study has a single-group design. Its primary comparison is within participants across two measurement times, not between randomized treatment groups. Even if a numerical before-and-after change were available, that contrast alone would not isolate the effect of 13vPnC from other possible influences on measurements over time. There is no concurrent control group described for evaluating what would have happened over the same period without the schedule or under another schedule.
The listed enrollment is 303, but that figure is not the number analyzed for the primary endpoint. The endpoint population required vaccination as assigned, appropriately timed blood draws, at least 1 valid determinate assay result, and no major protocol violation. The number meeting those criteria is not reported in the registry record. It is therefore not possible to assess endpoint-specific completeness or how the analyzed population compares with the enrolled group.
The safety record gives numbers at risk and numbers affected for serious and other adverse events at different vaccination stages and follow-up. These counts describe reported events in the recorded groups; they do not establish that vaccination caused an event. The registry record does not report deaths for these categories. The serious-event terms listed with percentages also require context about event definitions, observation windows, and attribution, which is not reported in the registry record.
Overall, the posted information supports a description of the intended immune-response question and the reported safety counts, but not a conclusion about the size or precision of the primary immune response. It also does not support a randomized comparative safety or efficacy claim.
9. Statistical Methods Explained
What does a geometric mean fold rise represent?
For each participant with measurements at both specified assessment times, a fold rise expresses the later antibody measurement relative to the earlier measurement. A fold rise above 1 represents an increase on that ratio scale; a value below 1 represents a decrease. This is a general explanation of ratio measures, not a statement about the unreported trial result.
The geometric mean is calculated through logarithms: individual fold rises are transformed, summarized on the log scale, and transformed back. This method is useful when positive measurements or ratios are unevenly distributed, because very large values can otherwise have strong influence on an arithmetic mean. The registry states that the assay results were logarithmically transformed and that the GMFR was calculated from the mean logarithm of the fold rise.
How should the confidence interval be read?
A confidence interval describes uncertainty around an estimated quantity under the assumptions of its statistical method. In general, it gives a range of values reasonably compatible with the observed data and method; it is not a guarantee that the true value falls within that particular interval. The registry describes a Student t-based confidence interval for the mean logarithm of the fold rise, transformed back to the fold-rise scale. That transformation produces an interval expressed on the same scale as the GMFR.
The actual GMFR and confidence interval are not reported in the registry record. The method description therefore explains how an estimate was intended to be formed but does not allow its size or precision to be assessed. A statistical method description is not a substitute for the numerical result.
Why analyze serotypes separately or together?
The primary endpoint concerns the specified 13 serotypes. The registry also lists secondary outcomes for serotype-specific IgG concentrations and opsonophagocytic activity (OPA), with summaries across participant groups. Serotype-level measures can be informative because responses may differ by serotype. In general, summaries across several serotypes should not be read as proof that the response is the same for every serotype; the individual estimates and their uncertainty would be needed to assess that pattern. Those numerical results are not reported in the registry record.
OPA is a laboratory measure of antibody function, while IgG concentration measures antibody quantity. They address related but distinct features of an immune response. Neither laboratory measure alone establishes a clinical outcome. Interpretation of either depends on the measurement methods, the estimates, their uncertainty, and the clinical context.
Why can dispersion and skew matter?
Immune-response measurements can vary substantially among participants. General statistical practice uses transformations or distribution-aware summaries when measurements are skewed. The logarithmic approach described for the GMFR makes the analysis correspond to relative rather than absolute change. The record does not report individual-level distributions or a numerical measure of variability beyond the stated confidence-interval method, so the spread of participant responses cannot be assessed.
Over-dispersion is a general issue that arises when observed variability exceeds what a statistical model assumes. It can make standard errors too small if the model does not account for the extra variability. The registry description does not report a model for count data or an over-dispersion adjustment for the primary endpoint; this is not an indication that such an adjustment was needed. The stated endpoint method instead refers to log-transformed assay results and a Student t-based interval.
What does the single-group comparison establish?
The primary contrast uses measurements from the same participants at two times. In general, paired measurements can account for stable differences between participants because each participant contributes measurements at both assessments. However, a within-participant change is not the same as a randomized treatment contrast. Time-related changes, other exposures, or changes in measurement conditions could also contribute. A single-group design cannot separate such influences in the way a concurrent randomized comparison is designed to do.
The record does not report the statistical analysis plan, any prespecified handling of multiple outcomes, or the numerical primary result. Thus the method can be described at the level stated in the endpoint definition, but additional analysis choices and their consequences are not reported in the registry record.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists 19 outcome measures, including the primary GMFR and several secondary measures of antibody concentration, OPA titers, and fold rise. When a study examines multiple outcomes, serotypes, or participant groups, the chance of at least one apparently notable result can increase. General methods for addressing this include prespecifying a hierarchy of outcomes or adjusting inference for multiple comparisons. Whether either approach was planned or used is not reported in the registry record. The record also lists 0 analyses, so no numerical results are available for evaluating the set of outcomes.
The primary endpoint population was restricted to participants who received vaccination as assigned, had blood drawn within prespecified time frames, had at least 1 valid, determinate assay result, and had no major protocol violation. The GMFR calculation was to use participants with data from both post-Dose 2 and post-Dose 3 blood draws. These criteria define who could contribute to the endpoint; they do not state how many participants met them.
Missing blood draws, invalid assays, or exclusions for protocol violations can reduce the information available for an endpoint. If participants with and without usable measurements differ, the analyzed group may not represent all enrolled participants. General statistical interpretation therefore benefits from knowing the number analyzed, reasons for missingness or exclusion, and any sensitivity analyses. Those details are not reported in the registry record.
The enrollment figure is 303, but it should not be treated as the primary endpoint denominator. The endpoint-specific analyzed number and methods for handling missing measurements are not reported in the registry record. No sample-size justification, interim analyses, or detailed statistical plan is 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 |
|---|---|---|---|
| Prior 13vPnC Dose 1 | 1 | 301 | 0.3% |
| 13vPnC Dose 1 | 1 | 301 | 0.3% |
| 13vPnC Dose 2 | 4 | 290 | 1.4% |
| 13vPnC Dose 3 | 1 | 286 | 0.3% |
| 23vPS Dose | 0 | 282 | 0.0% |
| Follow-up | 1 | 282 | 0.4% |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Prior 13vPnC Dose 1 | 16 of 301 |
| 13vPnC Dose 1 | 216 of 301 |
| 13vPnC Dose 2 | 171 of 290 |
| 13vPnC Dose 3 | 137 of 286 |
| 23vPS Dose | 31 of 282 |
| Follow-up | 2 of 282 |
Most frequent serious adverse event terms
| Event term | Organ system | Prior 13vPnC Dose 1 | 13vPnC Dose 1 | 13vPnC Dose 2 | 13vPnC Dose 3 | 23vPS Dose | Follow-up |
|---|---|---|---|---|---|---|---|
| Pharyngitis bacterial | Infections and infestations | 0 of 301 | 0 of 301 | 1 of 290 | 0 of 286 | 0 of 282 | 1 of 282 |
| Convulsion | Nervous system disorders | 0 of 301 | 1 of 301 | 0 of 290 | 0 of 286 | 0 of 282 | 0 of 282 |
| Haemorrhoids | Gastrointestinal disorders | 0 of 301 | 0 of 301 | 1 of 290 | 0 of 286 | 0 of 282 | 0 of 282 |
| Lobar pneumonia | Infections and infestations | 0 of 301 | 0 of 301 | 1 of 290 | 0 of 286 | 0 of 282 | 0 of 282 |
| Tonsillitis | Infections and infestations | 0 of 301 | 0 of 301 | 1 of 290 | 0 of 286 | 0 of 282 | 0 of 282 |
| Road traffic accident | Injury, poisoning and procedural complications | 0 of 301 | 0 of 301 | 0 of 290 | 1 of 286 | 0 of 282 | 0 of 282 |
| Lymphadenopathy | Blood and lymphatic system disorders | 1 of 301 | 0 of 301 | 0 of 290 | 0 of 286 | 0 of 282 | 0 of 282 |
| Croup infectious | Infections and infestations | 1 of 301 | 0 of 301 | 0 of 290 | 0 of 286 | 0 of 282 | 0 of 282 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Prior 13vPnC Dose 1 | 13vPnC Dose 1 | 13vPnC Dose 2 | 13vPnC Dose 3 | 23vPS Dose | Follow-up |
|---|---|---|---|---|---|---|---|
| Pain at injection site (Any) | Skin and subcutaneous tissue disorders | 0 of 0 | 156 of 238 | 166 of 236 | 131 of 213 | 0 of 0 | 0 of 0 |
| Pain at injection site (Mild) | Skin and subcutaneous tissue disorders | 0 of 0 | 127 of 228 | 139 of 227 | 107 of 201 | 0 of 0 | 0 of 0 |
| Muscle pain (Any) | General disorders | 0 of 0 | 126 of 226 | 97 of 216 | 81 of 191 | 0 of 0 | 0 of 0 |
| Fatigue (Any) | General disorders | 0 of 0 | 123 of 230 | 86 of 211 | 66 of 183 | 0 of 0 | 0 of 0 |
| Headache (Any) | General disorders | 0 of 0 | 111 of 220 | 81 of 207 | 57 of 177 | 0 of 0 | 0 of 0 |
| Muscle pain (Mild) | General disorders | 0 of 0 | 100 of 213 | 75 of 208 | 57 of 182 | 0 of 0 | 0 of 0 |
| Fatigue (Mild) | General disorders | 0 of 0 | 93 of 218 | 69 of 207 | 53 of 177 | 0 of 0 | 0 of 0 |
| Headache (Mild) | General disorders | 0 of 0 | 96 of 209 | 59 of 199 | 45 of 171 | 0 of 0 | 0 of 0 |
| Joint pain (Any) | General disorders | 0 of 0 | 79 of 205 | 61 of 201 | 49 of 174 | 0 of 0 | 0 of 0 |
| Joint pain (Mild) | General disorders | 0 of 0 | 63 of 199 | 43 of 193 | 37 of 170 | 0 of 0 | 0 of 0 |
Serious events with the highest arm-level rate: pharyngitis bacterial (0.4%), road traffic accident (0.3%), haemorrhoids (0.3%), lobar pneumonia (0.3%), tonsillitis (0.3%).
The registry reports serious adverse events and other adverse events by vaccination stage and follow-up, with numbers at risk and numbers affected. For serious adverse events, the recorded figures are: Prior 13vPnC Dose 1, 1 affected among 301 at risk; 13vPnC Dose 1, 1 among 301; 13vPnC Dose 2, 4 among 290; 13vPnC Dose 3, 1 among 286; 23vPS Dose, 0 among 282; and Follow-up, 1 among 282. These are stage-specific registry counts, not a randomized comparison.
For other adverse events, the figures are: Prior 13vPnC Dose 1, 16 among 301; 13vPnC Dose 1, 216 among 301; 13vPnC Dose 2, 171 among 290; 13vPnC Dose 3, 137 among 286; 23vPS Dose, 31 among 282; and Follow-up, 2 among 282. The numbers at risk vary by stage. The registry record does not explain the reasons for those differences, so they should not be interpreted as evidence about why participants were or were not represented at each stage.
The serious-event terms listed include Pharyngitis bacterial (0.4%), Road traffic accident (0.3%), Haemorrhoids (0.3%), Lobar pneumonia (0.3%), Tonsillitis (0.3%), and Convulsion (0.3%). These terms and percentages describe listed serious-event entries; the record does not report enough context to infer causation or compare risk with an untreated or alternative-treatment group. Deaths are not reported in the registry record.
12. What the Result Does, and Does Not, Mean
The record describes a study designed to assess safety, tolerability, and immunogenicity of a schedule combining 13vPnC and 23vPS in HIV-infected participants aged 6 years or older who were pneumococcal-vaccine naive. Its primary immune-response question is the change in serotype-specific IgG from 1 month after 13vPnC Dose 2 to 1 month after Dose 3, summarized as a geometric mean fold rise.
However, the registry record does not report the numerical primary endpoint estimate or its confidence interval. It therefore does not show how large or precise the measured change was. The endpoint definition and the specified analysis method explain what the investigators intended to estimate, but they do not establish the observed result. The same caution applies to the secondary immune-response outcomes: their descriptions are present, but their numerical results are not reported in the registry record.
The safety counts document participants affected by serious and other adverse events within the listed vaccination-stage and follow-up categories. In general, counts observed during a study are descriptive. They do not by themselves show that an intervention caused an event, and a single-group study cannot provide a randomized comparison of safety against another schedule or no vaccination.
The study also does not, from the information reported in the registry record, establish clinical protection against pneumococcal infection. Antibody concentration and laboratory activity are immune-response measures, not direct counts of disease prevented. No numerical clinical-outcome comparison is reported in the registry record.
Accordingly, the posted information permits a clear description of the trial question, endpoint construction, participant eligibility for the endpoint, and recorded adverse-event counts. It does not permit a quantitative conclusion about the primary immune response, its precision, comparative effects, or clinical benefit.
13. Why This Trial Matters Statistically
This trial illustrates a common distinction in clinical research: defining an endpoint and reporting its result are separate steps. The registry specifies a GMFR, the two assessment times, the 13 serotypes, the log-scale calculation, and the confidence-interval method. Yet without the numerical estimate and interval, readers cannot evaluate the magnitude or precision of the primary endpoint.
It also illustrates why study design determines the scope of inference. A single-group, open-label study can describe measurements and adverse events observed during a vaccination schedule. Its within-participant comparison can characterize change over time, but it cannot provide the same causal contrast as randomized assignment to different schedules or a control condition. The absence of a concurrent comparison group matters when interpreting any observed change or event count.
Endpoint populations matter as well. The primary measure requires paired blood-draw data and other evaluability conditions, whereas the enrollment figure describes the study overall. Without the endpoint-specific analyzed number and information about missing measurements, the completeness and representativeness of the immune-response analysis cannot be judged.
Finally, multiple outcomes and serotype-level measurements raise questions about how results were prioritized and interpreted. The registry lists 19 outcome measures, but the statistical plan and numerical analyses are not reported in the registry record. This makes it especially important to distinguish a stated analysis method from evidence about its result. These issues are broadly relevant when reading immunogenicity trials, especially when laboratory endpoints, population exclusions, and descriptive safety summaries are presented without a comparative result.
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 main trial-specific limitation in the registry record is the absence of numerical primary and secondary outcome results. Although the record describes the primary GMFR and its confidence-interval method, it does not report an estimate, confidence interval, or endpoint-specific analyzed number. The listed enrollment of 303 cannot substitute for those details.
The single-group, open-label design has no randomized comparator described in the record. The primary endpoint compares measurements at two times within the vaccination schedule, so it cannot isolate changes attributable to one dose from other influences that may change over time. The design also does not permit a like-for-like comparison of adverse-event rates against another treatment group.
The evaluable immunogenicity population excludes participants who did not meet the stated vaccination, blood-draw, assay, or protocol criteria. The registry record does not report how many were excluded, the reasons for missing endpoint data, or whether sensitivity analyses were conducted. Those omissions limit assessment of potential selection effects and the robustness of the endpoint analysis.
The record lists multiple outcome measures but does not report a multiplicity strategy, a full statistical analysis plan, or numerical analyses. It also does not report a sample-size justification or interim analyses. These details should not be inferred from the trial phase or enrollment figure. Finally, the safety summaries are descriptive, and deaths are not reported in the registry record; attribution, observation-window details, and comparative safety estimates are not reported in the registry record.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Safety and Immunogenicity of 13-Valent Pneumococcal Conjugate Vaccine (13vPnC) in HIV-Infected Subjects 6 Years of Age or Older Who Are Naive to Pneumococcal Vaccine — NCT00962780.
- Registry record last updated 2014-11-17; status last verified 2014-11.
- Results first posted 2014-11-17.
- 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
NCT00962780 was a completed Phase 3, open-label, single-group trial sponsored by Pfizer. It enrolled 303 HIV-infected participants aged 6 years or older who had not previously received a pneumococcal vaccine. The recorded study start was 2010-03, and primary completion was 2013-04.
The planned schedule included 3 doses of 13vPnC and 1 dose of 23vPS, with each dose given approximately 1 month apart. The primary endpoint was the geometric mean fold rise in serotype-specific IgG from 1 month after 13vPnC Dose 2 to 1 month after Dose 3, across 13 serotypes. Its analysis used log-transformed assay results and a Student t-based confidence interval transformed back to the fold-rise scale.
The registry lists 19 outcome measures and 0 analyses. Numerical immune-response results and the endpoint-specific analyzed number are not reported in the registry record. Safety counts are listed by vaccination stage and follow-up, without a randomized comparator.