This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for A Study of a New Vaccine Against Two Types of Ebola (NCT05079750), a non-randomized phase 1 study. The primary outcome is Safety and Tolerability of ChAdOx1 biEBOV in Healthy Volunteers: Number of Participants With Occurrence of Solicited Local and Systemic Reactogenicity Signs and Symptoms.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT05079750 |
| Phase | Phase 1 |
| Condition | Ebola |
| Allocation | Non-Randomized |
| Design model | Sequential |
| Masking | None (open label) |
| Enrollment | 26 |
| Arms in the primary outcome | n/a |
| Lead sponsor | University of Oxford |
| Results posted | Yes |
2. Clinical Question
Population
Healthy adult volunteers in the UK were enrolled in a first-in-human Phase I trial. The registry lists an enrollment of 26. These results concern the volunteers enrolled in this study, not a patient population with Ebola.
Intervention
The intervention was ChAdOx1 biEBOV, a bivalent ChAdOx1 vectored vaccine intended to address Zaire and Sudan Ebola virus species. Participants received different dose levels; the high-dose group included a single-dose regimen and a two-dose regimen twelve weeks apart.
Comparator
There was no randomized control arm. The registry describes a non-randomized, open-label, sequential dose-escalation study. Dose groups can be described alongside one another, but they are not randomized, like-for-like treatment comparisons.
Primary question
The primary question concerned safety and tolerability, assessed through the occurrence of solicited local and systemic reactogenicity signs and symptoms during the 7 days following vaccination. The registry also identifies humoral and cellular immunogenicity as secondary outcomes, but their results are not reported in the registry record.
The study therefore asks an early-stage question about the observed safety experience and immune responses after vaccination in healthy adult volunteers. It does not test whether vaccination prevents Ebola infection or disease. The registry’s primary endpoint description focuses on symptoms participants were asked about after vaccination, and also specifies reporting the maximum severity of local and systemic solicited symptoms for individual participants. That endpoint is distinct from the secondary immunogenicity outcomes, which concern immune response measures.
Because assignment was non-randomized and sequential, differences between dose groups should not be read as if they arose from a randomized comparison. The registry record does not report a control group, a causal contrast, or a prespecified comparative estimate. The available safety counts can describe what was recorded in each listed group, but they do not by themselves establish that dose level caused a difference in event frequency.
3. Trial Design
This was a completed, open-label, non-randomized, dose-escalation, first-in-human, single-centre Phase I study sponsored by the University of Oxford. The registry describes the intended population as healthy adult volunteers in the UK. The study began on 2021-11-11 and had a primary completion date of 2023-03-21. Its registered enrollment was 26.
The arm descriptions identify a low-dose group of 6 participants and a mid-dose group of 6 participants, each receiving a single vaccination. The high-dose description covers 14 participants: 7 received a single dose and 7 received two doses twelve weeks apart. The registry’s adverse-event listing uses the labels “High Dose 1” and “High Dose 2”; the relationship between those labels and the regimen descriptions is not explained in the registry record. The listed group labels and counts should therefore be interpreted as recorded rather than treated as evidence of a randomized comparison.
“Sequential” and “dose escalation” describe the broad design structure: dose levels were studied in sequence rather than assigned through random allocation. The registry record does not report the detailed escalation rules, criteria for moving between dose levels, or the timing of any review between groups. Masking is listed as none, so this was an open-label study. The record does not report a placebo or other control intervention.
As an early clinical study, its registered focus was safety, tolerability, and immunogenicity. The primary outcome description concerns solicited local and systemic reactogenicity during the 7 days following vaccination. Humoral and cellular immunogenicity are listed as secondary outcomes. The registry record does not report the statistical analysis plan, the analysis populations, or the detailed procedures used to summarize those secondary outcomes. The completed status indicates the registry lists the trial as completed; it does not, by itself, supply results for every registered outcome.
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 | Group 1: Low Dose | Group 2: Mid Dose | Group 3: High Dose |
|---|---|---|---|
| STARTED | 6 | 6 | 14 |
| COMPLETED | 6 | 6 | 13 |
| NOT COMPLETED | 0 | 0 | 1 |
Reasons for not completing this period:
| Reason | Group 1: Low Dose | Group 2: Mid Dose | Group 3: High Dose |
|---|---|---|---|
| Lost to Follow-up | 0 | 0 | 1 |
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 | Group 1: Low Dose | Group 2: Mid Dose | Group 3: High Dose - Single Dose | Group 3: High Dose - Two Doses | Total |
|---|---|---|---|---|---|---|
| Participants analysed | 6 | 6 | 7 | 7 | 26 | |
| Age, Customized | years | 24 (19 to 31) | 26 (22 to 32) | 20 (19 to 28) | 30 (28 to 33) | 28 (20 to 43) |
| Sex: Female, Male: Female | Participants | 4 | 3 | 5 | 4 | 16 |
| Sex: Female, Male: Male | Participants | 2 | 3 | 2 | 3 | 10 |
| Race/Ethnicity, Customized: White | Participants | 6 | 4 | 4 | 7 | 21 |
| Race/Ethnicity, Customized: Black Carribean and Mixed White or | Participants | 0 | 1 | 0 | 0 | 1 |
| Race/Ethnicity, Customized: Asian or Asian British | Participants | 0 | 0 | 2 | 0 | 2 |
| Race/Ethnicity, Customized: Other Asian Background | Participants | 0 | 1 | 1 | 0 | 2 |
| Region of Enrollment: United Kingdom | Participants | 6 | 6 | 7 | 7 | 26 |
6. Primary Endpoint
The registry lists the primary outcome as Safety and Tolerability of ChAdOx1 biEBOV in Healthy Volunteers: Number of Participants With Occurrence of Solicited Local and Systemic Reactogenicity Signs and Symptoms, measured over 7 days following vaccination.
| Element | Registry entry |
|---|---|
| Result type | Count Of Participants |
| Measure of spread | not applicable |
| Unit | Participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint is the number of participants with solicited local and systemic reactogenicity signs and symptoms during the 7 days following vaccination. The registry’s description says the data are presented as the number and percentage of participants reporting each event. It also specifies the maximum severity of any local and any systemic solicited symptoms reported by each participant.
Solicited symptoms are events that are actively sought rather than recorded only when participants volunteer them. In general, this approach can make symptom ascertainment more consistent: participants are asked about specified events over a defined follow-up period. It is useful in early vaccine studies because short-term local and systemic reactions are part of the safety and tolerability profile being assessed. The registry record does not list the individual solicited symptoms or their results in the registry record for this analysis.
The participant is the unit of the stated endpoint. A participant may report more than one symptom, so event counts and counts of participants with at least one event would answer different questions. The registry description distinguishes event-specific reporting from the participant-level maximum severity summary. Those summaries help characterize the kinds and severity of symptoms recorded, but they do not substitute for longer-term safety follow-up or for immunogenicity outcomes.
The primary endpoint definition is not itself a finding. The actual results for solicited local and systemic symptoms, including their counts, percentages, and severity summaries, are not reported in the registry record. The posted adverse-event counts described elsewhere are not a replacement for those specific primary endpoint results.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The safety figures in the registry record are descriptive counts by listed group. For serious adverse events, the record lists 1 affected participant among 6 at risk in Group 1: Low Dose, and 0 among 6 in Group 2: Mid Dose, 0 among 14 in Group 3: High Dose 1, and 0 among 7 in Group 4: High Dose 2. The record lists 0 deaths in each of these groups. For other adverse events, the corresponding affected-participant counts are 6, 5, 12, and 5, with at-risk counts of 6, 6, 14, and 7. These are descriptions of the recorded counts, not estimates of comparative treatment effects.
The record also lists “Endometriotic cyst” among the top serious adverse event terms, with 16.7%. The registry information does not provide enough event-level context to determine how that term relates to the group summaries, its timing, or whether it was considered related to vaccination. A serious adverse event is not automatically an event caused by the intervention. Causality and clinical context cannot be inferred from a term and percentage alone.
The groups were not randomized, and the study was open-label and sequential. Group differences may reflect the design and the participants enrolled at different stages, as well as the different dose regimens. No randomized control comparison is registered. The listed counts therefore do not support a causal claim that a particular dose level produced more or fewer events than another. Small group counts also make descriptive estimates imprecise; without confidence intervals or other uncertainty estimates, the registry figures do not show how uncertain an underlying event frequency may be.
The registry record does not report the primary endpoint’s solicited symptom results, the humoral or cellular immunogenicity results, or inferential analyses for these outcomes. It also does not report confidence intervals, hypothesis tests, or adjusted comparisons in the registry record for this analysis. Consequently, the adverse-event counts should not be read as a complete account of the primary endpoint, nor as evidence about immune response magnitude.
Planning illustrations based on an observed effect are not observed power and do not add evidence about this study’s outcomes. The registry record does not report the trial’s own sample-size justification. Taken together, the posted counts offer a limited descriptive account of safety events by recorded group. They do not establish comparative safety, efficacy against Ebola, or the size and precision of immune responses.
9. Statistical Methods Explained
Clinical-trial results can be summarized descriptively or analyzed to estimate a contrast between groups. A descriptive summary reports what was observed in the participants included in each group. An inferential analysis attempts to quantify uncertainty around an estimate or assess a specified hypothesis. The registry entries available for this analysis include event counts by group but do not report a statistical analysis plan, confidence intervals, or hypothesis tests for the trial outcomes.
What does a participant count represent?
For a binary event outcome, each participant is classified according to whether the event occurred under the outcome’s definition. The affected-participant count is interpreted alongside the number at risk, which provides the group denominator. Counts are useful for showing how many people were recorded with an event, but they do not alone describe precision. In general, a confidence interval expresses a range of values compatible with the observed data under a statistical method. Its width reflects uncertainty as well as the amount and pattern of information in the data. No confidence intervals for the adverse-event counts are reported in the registry record.
Counts of participants with an event must also be distinguished from counts of events. A participant can report multiple symptoms or experience multiple events, depending on the endpoint definition. The primary endpoint description specifies participant counts for each solicited symptom and maximum severity per participant; it does not give the results in the registry record for this analysis. The serious and other adverse-event summaries are separate group-level summaries, and the record does not provide enough event-level detail to determine overlap between categories or terms.
Why are dose groups not a randomized comparison?
Random allocation is commonly used to balance, on average, both measured and unmeasured participant characteristics between comparison groups. This study is registered as non-randomized and sequential, so that protection against allocation-related differences is not available in the same way. The dose groups were also part of dose escalation, rather than concurrent randomized arms. Any difference in observed counts could be influenced by group composition, study sequence, follow-up, or regimen, as well as by dose. The registry record does not report an adjusted analysis that addresses these possibilities. The group counts should therefore be interpreted descriptively, not as a direct estimate of a causal dose effect.
Open-label status means masking is listed as none. In general, awareness of treatment assignment can affect the reporting or assessment of subjective outcomes. Solicited symptom collection can standardize what is asked, but it does not remove every possible influence of awareness. The registry record does not describe additional steps used to reduce assessment or reporting bias.
What can a planning illustration tell readers?
A sample-size planning illustration asks what sample size might be needed under specified statistical assumptions to detect a chosen effect. The registered illustration assumptions state a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation, with the target effect expressed as a fraction of the observed effect. Such an illustration is a planning exercise, not a result of the trial and not observed power. It does not establish that the trial was designed around those assumptions. The trial’s own sample-size justification is not reported in the registry record.
Planning estimates depend on the assumed effect, variability or event frequency, analysis method, and allocation structure. If the assumed effect is smaller, a planning exercise generally requires more information to distinguish it from no effect at a chosen error rate; that is a general statistical principle, not a finding from this trial. The registry’s description of the illustration does not provide the calculated planning values in the registry record for this analysis, so no sample-size recommendation can be stated. The illustration also assumes equal allocation between two arms, whereas this study’s registered design was sequential and non-randomized. That distinction matters when interpreting whether a planning calculation maps to the actual design.
How should uncertainty and multiple outcomes be considered?
Uncertainty is especially important when interpreting event counts from groups of limited size. A count may be compatible with a range of underlying event frequencies, and a zero count does not establish that an event cannot occur. General methods for sparse binary outcomes may use exact or other small-sample approaches rather than rely on large-sample approximations. The registry record does not state which methods were used for any outcome analysis. No uncertainty estimate should be inferred from the counts alone.
The registry lists 6 outcome measures, including the primary safety outcome and secondary humoral and cellular immunogenicity outcomes, and lists 0 analyses. These registry entries do not specify how multiple outcomes were handled in the study’s statistical plan. When multiple outcomes are assessed, the chance of at least one apparently notable result can increase if each is tested separately; general approaches include prespecifying a primary outcome or adjusting interpretation for multiplicity. The applicable strategy for this trial is not reported in the registry record.
Finally, analysis populations and missing-data procedures affect what a result means. For example, an analysis may include all enrolled participants, participants who received a specified intervention, or participants with outcome data, and the denominator can differ accordingly. The registry record does not report the analysis population definitions, how missing observations were handled, or whether follow-up completeness varied across groups. Those omissions limit the ability to assess the completeness and comparability of the posted results.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists 6 outcome measures and identifies safety and tolerability as the primary outcome, with humoral and cellular immunogenicity as secondary outcomes. It lists 0 analyses. These entries do not provide a full statistical analysis plan or explain whether any outcomes were tested inferentially. A multiplicity strategy, such as a prespecified hierarchy or adjustment for multiple comparisons, is not reported in the registry record.
Multiplicity matters when a study assesses several outcomes or several event categories. In general, interpreting many separate tests without accounting for their number can make apparently unusual findings more likely by chance. That general concern does not imply that a particular result in this trial is false; it means readers need to know which analyses were planned and how they were interpreted. The registry information does not specify the planned testing strategy, or whether any interim analyses were conducted.
The analysis populations are not reported in the registry record. The record also does not report how missing outcome data were handled, whether participants with incomplete follow-up were included in each analysis, or how missingness was assessed. These details matter because participant counts, denominators, and symptom summaries can depend on which observations are available and which participants are included. The registry’s enrolled count should not be assumed to be the denominator for every outcome.
Accordingly, the posted event counts can be read as the listed group summaries, but the available information does not establish that every enrolled participant contributed to every outcome or explain how missing observations may have affected the summaries.
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: Low Dose | 1 | 6 | 16.7% |
| Group 2: Mid Dose | 0 | 6 | 0.0% |
| Group 3: High Dose 1 | 0 | 14 | 0.0% |
| Group 4: High Dose 2 | 0 | 7 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Group 1: Low Dose | 0 of 6 |
| Group 2: Mid Dose | 0 of 6 |
| Group 3: High Dose 1 | 0 of 14 |
| Group 4: High Dose 2 | 0 of 7 |
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 |
|---|---|
| Group 1: Low Dose | 6 of 6 |
| Group 2: Mid Dose | 5 of 6 |
| Group 3: High Dose 1 | 12 of 14 |
| Group 4: High Dose 2 | 5 of 7 |
Most frequent serious adverse event terms
| Event term | Organ system | Group 1: Low Dose | Group 2: Mid Dose | Group 3: High Dose 1 | Group 4: High Dose 2 |
|---|---|---|---|---|---|
| Endometriotic cyst | Reproductive system and breast disorders | 1 of 6 | 0 of 6 | 0 of 14 | 0 of 7 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Group 1: Low Dose | Group 2: Mid Dose | Group 3: High Dose 1 | Group 4: High Dose 2 |
|---|---|---|---|---|---|
| Solicited systemic AEs | Immune system disorders | 6 of 6 | 5 of 6 | 12 of 14 | 5 of 7 |
| Solicited local AEs | Skin and subcutaneous tissue disorders | 3 of 6 | 4 of 6 | 10 of 14 | 5 of 7 |
| Headache | Nervous system disorders | 1 of 6 | 2 of 6 | 3 of 14 | 3 of 7 |
| Oropharyngeal pain | Respiratory, thoracic and mediastinal disorders | 1 of 6 | 2 of 6 | 4 of 14 | 2 of 7 |
| Cough | Respiratory, thoracic and mediastinal disorders | 2 of 6 | 2 of 6 | 1 of 14 | 3 of 7 |
| Fatigue | General disorders | 3 of 6 | 0 of 6 | 1 of 14 | 2 of 7 |
| Diarrhoea | Reproductive system and breast disorders | 1 of 6 | 1 of 6 | 0 of 14 | 2 of 7 |
| COVID-19 | Infections and infestations | 0 of 6 | 1 of 6 | 0 of 14 | 3 of 7 |
| Dizziness | Nervous system disorders | 0 of 6 | 1 of 6 | 2 of 14 | 0 of 7 |
| Nasal congestion | Respiratory, thoracic and mediastinal disorders | 0 of 6 | 0 of 6 | 1 of 14 | 2 of 7 |
Serious events with the highest arm-level rate: endometriotic cyst (16.7%).
The registry lists serious adverse events by group as affected-participant counts alongside the number at risk: 1 among 6 in Group 1: Low Dose, and 0 among 6 in Group 2: Mid Dose, 0 among 14 in Group 3: High Dose 1, and 0 among 7 in Group 4: High Dose 2. It lists 0 deaths in each group. The other adverse-event counts are 6 among 6, 5 among 6, 12 among 14, and 5 among 7, respectively. These counts should be read as the recorded summaries, not as a comparison adjusted for study design.
The registry lists “Endometriotic cyst” as a top serious adverse event term, with 16.7%. It does not report enough context to establish the event’s timing, relationship to vaccination, or relation to the group-level summary. A serious event is not necessarily caused by the intervention; attribution requires information beyond its classification as serious.
Zero recorded events in a group does not demonstrate that the underlying risk is zero. With limited group information, the observed counts cannot precisely establish the frequency of uncommon events. The registry record does not report confidence intervals for these counts or event-level narratives. In addition, its high-dose labels in the adverse-event listing are not fully explained in relation to the arm descriptions. These figures are therefore best treated as a safety description requiring context, not as a definitive comparison between regimens.
12. What the Result Does, and Does Not, Mean
The registry record describes a completed early-stage study of ChAdOx1 biEBOV in healthy adult volunteers. Its design was non-randomized, open-label, sequential, and focused on dose escalation. The posted serious and other adverse-event counts provide a descriptive account by listed group, and the registry records 0 deaths in each group. Those observations are limited to the participants and outcomes recorded in this study.
The figures do not establish that one dose level is safer than another. The groups were not randomized, and the record does not provide a comparative analysis or uncertainty estimates. Counts alone cannot establish whether differences reflect treatment, participant characteristics, study sequence, or other factors. The serious adverse event term and percentage also do not establish that the event was caused by vaccination.
The findings described in the available registry information do not demonstrate whether the vaccine prevents Ebola, nor do they establish a clinical benefit. Prevention of infection or disease is not the primary endpoint described in the record. Humoral and cellular immunogenicity are registered secondary outcomes, but their results are not reported in the registry record. The primary endpoint’s solicited symptom counts, percentages, and severity results are also not reported in the registry record for this analysis.
Statistical precision cannot be judged from the posted counts alone. The registry record does not report confidence intervals, hypothesis tests, or the analysis populations and missing-data procedures needed to interpret outcome completeness. A planning illustration based on an observed effect is not evidence of power achieved in this trial and should not be used as a substitute for reported outcome estimates.
The appropriate interpretation is therefore narrow: the record provides group-level safety counts from a Phase I study, but the available information does not support a definitive comparative or efficacy conclusion. Further interpretation depends on complete outcome reporting, methods, and clinical context that are not reported in the registry record.
13. Why This Trial Matters Statistically
This trial is statistically informative as an example of the limits and purpose of early-stage clinical evidence. A first-in-human Phase I study can describe short-term safety and tolerability while assessing immune responses. The design and endpoint definitions matter because they determine what the resulting counts can answer. Here, the registered primary endpoint concerns solicited symptoms during the 7 days following vaccination, rather than prevention of Ebola disease.
The sequential dose-escalation design also illustrates why group comparisons require care. Counts from non-randomized groups can describe what was observed, but they do not have the same interpretation as a randomized comparison. Dose, regimen, participant composition, and study sequence can be entangled. Without a randomized control group and a reported comparative analysis, a numerical difference between groups cannot be isolated as a treatment effect.
The record also highlights the importance of complete reporting. The primary endpoint definition is available, but its symptom results are not reported in the information available for this analysis. Immunogenicity outcomes are registered, but their results are not reported either. Analysis populations, missing-data handling, confidence intervals, and the multiplicity strategy are also not reported. These elements are essential for understanding how complete, precise, and interpretable outcome summaries are.
Finally, the presence of event counts does not make a result conclusive. Descriptive counts are useful for understanding what was recorded, while estimates of uncertainty and clear outcome definitions help readers judge how much those observations can support. This study’s record therefore offers a practical lesson in separating the purpose of a Phase I study from claims that would require different outcomes and stronger comparative evidence.
14. Limitations
- The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
- Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.
The registry information available for this analysis leaves important outcome details unreported. Although the primary endpoint is defined as solicited local and systemic reactogenicity during the 7 days following vaccination, its actual event-specific counts, percentages, and severity summaries are not reported in the registry record. The humoral and cellular immunogenicity outcomes are listed, but their results are not reported either.
The study was non-randomized, open-label, and sequential, with no randomized control group described. This limits causal interpretation of differences among dose groups. The registry record does not report detailed escalation criteria, the timing of group reviews, or a statistical analysis plan. It also does not report confidence intervals or hypothesis tests for the listed event counts.
Further limitations arise from missing methodological detail. The analysis populations, missing-data procedures, follow-up completeness, and multiplicity strategy are not reported in the registry record. The adverse-event listing’s High Dose 1 and High Dose 2 labels are not fully explained in relation to the arm descriptions, which describe a high-dose group containing single-dose and two-dose regimens. The record does not provide event-level narratives or enough context to interpret the serious adverse event term and its percentage.
The registry lists a planning illustration based on specified assumptions, but the trial’s own sample-size justification is not reported. A planning illustration is not observed power and does not resolve uncertainty about the outcomes. These limitations mean the posted counts should be treated as a narrow descriptive record rather than a complete assessment of safety, immunogenicity, or comparative effects.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: A Study of a New Vaccine Against Two Types of Ebola — NCT05079750.
- Registry record last updated 2025-04-04; status last verified 2021-10.
- Results first posted 2025-04-04.
- 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
NCT05079750 is a completed Phase I study sponsored by the University of Oxford. The official title describes a study of a bivalent ChAdOx1 vectored vaccine against Zaire and Sudan Ebola virus species in healthy adult volunteers. The registry describes the design as open-label, non-randomized, sequential, and dose-escalating, with enrollment of 26. The study began on 2021-11-11 and had a primary completion date of 2023-03-21.
The primary outcome concerns solicited local and systemic reactogenicity signs and symptoms during the 7 days following vaccination. Humoral and cellular immunogenicity are registered secondary outcomes. The available registry information lists group-level counts for serious and other adverse events and 0 deaths in each listed group. It does not report the primary symptom results or immunogenicity results in the registry record for this analysis. Comparative analyses, uncertainty estimates, analysis populations, and missing-data methods are not reported in the registry record.