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 Efficacy of R0.6C Vaccine (NCT04862416), a randomized phase 1 study. The primary outcome is Number of Serious Adverse Events and Grade 3 Adverse Events.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT04862416 |
| Phase | Phase 1 |
| Condition | Malaria, Malaria,Falciparum |
| Allocation | Randomized |
| Design model | Sequential |
| Masking | None (open label) |
| Enrollment | 32 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Radboud University Medical Center |
| Results posted | Yes |
2. Clinical Question
Population
Healthy malaria-naïve adults in the Netherlands. The study is described as first-in-human and single-site. The registry records enrollment of 32 participants.
Intervention
R0.6C transmission blocking vaccine, given with Alhydrogel alone or with Matrix M1. The arm descriptions include 30 ug and 100 ug doses, with four planned vaccinations on days 0, 28, 56 and 168.
Comparator
The study includes arms with different vaccine doses and adjuvant combinations. It is randomized, but the registry does not report a single comparison as the basis for the posted primary outcome analysis.
Primary question
The primary outcome counts serious adverse events and solicited or unsolicited Grade 3 adverse events considered possibly, probably or definitely related to vaccination, from first administration through 84 days after the last immunization.
This is an early-stage safety and activity study, rather than a confirmatory comparison with a single control arm. Its stated aims are to assess safety, tolerability and Plasmodium falciparum transmission-reducing activity for R0.6C in two adjuvant combinations. The listed secondary outcomes are Grade 1 and 2 adverse events, transmission-reducing activity and anti-6C antibody quantities.
The posted record gives the study population, intervention arms and primary safety outcome, but it does not report a numerical estimate for transmission-reducing activity or antibody quantities. It also does not set out a single treatment contrast for an efficacy conclusion. The practical statistical question is therefore how to read the small, arm-specific safety summaries, while keeping the limits of the available outcome information in view.
3. Trial Design
The registry describes a phase I, first-in-human, open-label, single-site, dose-escalation study. Allocation is randomized, masking is none, and the study model is sequential. The study is recorded as completed. Enrollment is 32. The recorded start date is 2021-05-17 and the primary completion date is 2022-06-29.
The arms vary by vaccine dose and adjuvant. At 30 ug, the descriptions include R0.6C with Alhydrogel alone and R0.6C with Alhydrogel plus Matrix M1. The same two adjuvant combinations are listed at 100 ug. Each arm description specifies four vaccinations on days 0, 28, 56 and 168. Arm-level planned participant counts are shown in the registry record; these descriptions are not a substitute for participant-level accounting or an analysis population definition.
The sequential dose-escalation structure matters when interpreting the arm summaries. It means that the study is organized across a sequence of groups rather than as one simple, prespecified two-arm comparison. The record does not report the operational rules for escalation or how decisions were made between groups. It is also not reported in the registry record whether any additional comparisons were prespecified.
The trial is open-label, so the registry does not describe masking of participants or study staff. Open-label status is relevant context for outcomes that depend on reporting or assessment, although the record does not provide enough detail to assess how adverse events were elicited or adjudicated. The study’s setting, population and phase also constrain how broadly its findings can be interpreted: the record concerns healthy malaria-naïve adults in one site, and does not describe other populations.
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.
Only the first 6 of 8 groups are shown.
Overall Study
| Stage | 1A 30μg R0.6C Alhydrogel | 1B 30μg R0.6C Alhydrogel + Matrix M1 | 2A 30μg R0.6C Alhydrogel | 2B 30μg R0.6C Alhydrogel + Matrix M1 | 3A 100μg R0.6C Alhydrogel | 3B 100μg R0.6C Alhydrogel + Matrix M1 |
|---|---|---|---|---|---|---|
| STARTED | 3 | 3 | 5 | 5 | 3 | 3 |
| COMPLETED | 3 | 2 | 5 | 4 | 3 | 3 |
| NOT COMPLETED | 0 | 1 | 0 | 1 | 0 | 0 |
Reasons for not completing this period:
| Reason | 1A 30μg R0.6C Alhydrogel | 1B 30μg R0.6C Alhydrogel + Matrix M1 | 2A 30μg R0.6C Alhydrogel | 2B 30μg R0.6C Alhydrogel + Matrix M1 | 3A 100μg R0.6C Alhydrogel | 3B 100μg R0.6C Alhydrogel + Matrix M1 |
|---|---|---|---|---|---|---|
| Withdrawal by Subject | 0 | 1 | 0 | 1 | 0 | 0 |
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.
Only the first 6 of 9 groups are shown.
| Characteristic | Unit | 1A 30μg R0.6C Alhydrogel | 1B 30μg R0.6C Alhydrogel + Matrix M1 | 2A 30μg R0.6C Alhydrogel | 2B 30μg R0.6C Alhydrogel + Matrix M1 | 3A 100μg R0.6C Alhydrogel | 3B 100μg R0.6C Alhydrogel + Matrix M1 |
|---|---|---|---|---|---|---|---|
| Participants analysed | 3 | 3 | 5 | 5 | 3 | 3 | |
| Age, Categorical: <=18 years | Participants | 0 | 0 | 0 | 0 | 0 | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 3 | 3 | 5 | 5 | 3 | 3 |
| Age, Categorical: >=65 years | Participants | 0 | 0 | 0 | 0 | 0 | 0 |
| Age, Continuous | years | 22 (18 to 50) | 50 (19 to 53) | 23 (20 to 51) | 23 (23 to 44) | 27 (20 to 47) | 23 (20 to 23) |
| Sex: Female, Male: Female | Participants | 1 | 2 | 4 | 2 | 3 | 2 |
| Sex: Female, Male: Male | Participants | 2 | 1 | 1 | 3 | 0 | 1 |
| Race/Ethnicity, Customized: Caucasian | participants | 2 | 3 | 5 | 4 | 3 | 3 |
| Race/Ethnicity, Customized: Asian | participants | 0 | 0 | 0 | 1 | 0 | 0 |
| Race/Ethnicity, Customized: Brazilian | participants | 1 | 0 | 0 | 0 | 0 | 0 |
| Region of Enrollment: Netherlands | participants | 3 | 3 | 5 | 5 | 3 | 3 |
| Weight (kg) | kg | 84.6 (72.0 to 90.0) | 69.2 (68.6 to 73.4) | 67.0 (57.0 to 77.4) | 74.0 (61.0 to 75.6) | 82.6 (64.0 to 89.0) | 68.0 (65.0 to 72.8) |
6. Primary Endpoint
The registry lists the primary outcome as Number of Serious Adverse Events and Grade 3 Adverse Events, measured over From first immunization up to 84 days after the last immunization.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | adverse events |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is the number of serious adverse events and solicited and unsolicited Grade 3 adverse events considered possibly, probably or definitely related to the vaccine. The stated observation period begins with the first R0.6C administration and continues through 84 days after the last immunization.
This endpoint combines event severity with an assessment of possible relationship to vaccination. Serious adverse events and Grade 3 events are not interchangeable categories: seriousness generally concerns regulatory or clinical consequences, while grade describes severity. The registry’s wording identifies both kinds of events as relevant to this primary outcome. It does not report detailed criteria for grading, seriousness classification or attribution to vaccination.
General statistical context: an early-stage safety endpoint can describe whether specified events were observed during a defined follow-up period. The observation window is important because events outside it do not fall within the stated endpoint period. A count also differs from a count of participants: one participant may experience more than one event, while a participant-level summary records whether a person experienced at least one event. The record’s endpoint is expressed as a number of adverse events, but the posted safety table uses participant counts affected; the two summaries should not be treated as equivalent without event-level detail.
This kind of endpoint is used to characterize safety and tolerability during initial clinical evaluation. The registry does not report a formal hypothesis test or a prespecified threshold for interpreting the count.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The posted adverse-event table lists zero participants with serious adverse events in each of the eight arm rows. It also lists zero deaths in each arm. These are descriptive entries for the groups and outcomes shown. They do not establish that the vaccine has no risk, and they do not provide a precise estimate of the frequency of uncommon events.
For the table’s other adverse-event field, the number of participants affected is 3 in each arm with 3 participants at risk, and 5 in each arm with 5 participants at risk. The registry excerpt does not identify this field as the primary endpoint’s Grade 3 events, nor does it give the event grades, relatedness assessments or event-level counts for those entries. Accordingly, these values should not be read as the number of primary endpoint events. The table alone does not show which events were solicited or unsolicited, how severe they were, or whether they were judged possibly, probably or definitely related to vaccination.
The primary outcome description is more specific than the available tabular results: it concerns serious events and specified related Grade 3 events during a stated follow-up period. The posted table provides participant counts affected in separate serious and other adverse-event fields, but does not provide a direct event count for the complete primary outcome as described. The number of analyses is listed as 0, and no primary-outcome analysis estimate, confidence interval or p-value is posted in this record.
The trial includes dose and adjuvant variations, but the registry does not present one primary contrast for statistical comparison. Its note says the primary outcome has several categories or time points and was not reduced to one comparison. That limits what can be inferred from the available analysis display: readers can describe the arm-level entries, but cannot use them as evidence of a quantified between-group difference.
The stated secondary outcomes include transmission-reducing activity and anti-6C antibody quantities, as well as Grade 1 and 2 adverse events. Numerical results for these outcomes are not reported in the registry record. The study’s stated aims therefore extend beyond the outcomes that can be evaluated from the posted figures. The record supports a description of what is displayed, not a conclusion about vaccine activity or comparative efficacy.
General statistical context: with small groups, an absence of observed events still leaves uncertainty about the underlying event frequency. Confidence intervals, when reported, communicate the range of values compatible with the data under the analysis assumptions; none is reported for the primary outcome. The arm-level counts should therefore be interpreted as a limited description of observations in this study, not as a precise estimate of risk or a comparative treatment effect.
9. Statistical Methods Explained
What is the structure of the analysis?
The registry identifies a randomized, open-label, sequential, dose-escalation design. Random allocation means that assignment to study arms is described as randomized, but it does not by itself specify the allocation procedure, the randomization ratio or any stratification factors. Those details are not reported in the registry record. The sequential model indicates that the trial proceeds through groups in sequence, but the rules governing escalation, review or stopping are not reported in the registry record.
For statistical interpretation, this is not presented as a single two-arm study with one control and one experimental group. The listed arms differ in dose and adjuvant combination. In addition, the record explicitly notes that the primary outcome has several categories or time points and is not reduced to one comparison. The number of analyses is listed as 0. There is consequently no posted primary contrast, effect estimate or inferential test to interpret.
How should event counts be understood?
The primary endpoint is an event count, but the posted adverse-event rows report participants affected in serious and other adverse-event fields. An event count and a participant count answer different questions. Event counts can include repeated events for the same participant; participant counts usually indicate how many people experienced at least one event in a category. Without event-level data and a fuller table definition, the posted affected-participant figures should not be substituted for the primary event count.
General statistical context: counts are often summarized with methods that account for their distribution and for possible variation in event rates. Over-dispersion is a general concern when a count distribution varies more than a simple model expects; ignoring it can make uncertainty look too small. This record does not identify a count model, report a dispersion parameter, or provide a fitted estimate. It is therefore not possible to say which method, if any, was used to analyze the primary count.
What can an effect estimate or confidence interval contribute?
General explanation: an effect estimate summarizes the contrast or outcome quantity calculated from the study, while a confidence interval expresses uncertainty around that estimate under stated assumptions. A confidence interval is not a guarantee that the true value lies within its limits. Its interpretation depends on the design, analysis method and data used. In the posted record, no primary endpoint estimate or confidence interval is reported, so there is no such precision measure to interpret.
A p-value, when used, describes how compatible the data are with a specified null model under the analysis assumptions; it does not measure the probability that a treatment is effective. No p-value for the primary outcome is reported. The absence of a posted test does not establish that no analysis was performed elsewhere; it means the analysis is not reported in the registry record.
What does the planning illustration mean?
The sample-size section is described as a planning illustration computed from an observed effect, not as the trial’s own design. The stated assumptions are a two-sided significance level of 0.05, equal allocation between two arms and a normal approximation; the effect to detect is a stated fraction of the observed effect. For non-time-to-event tables, the illustration is expressed as participants per arm for a specified power. These are planning quantities, not observed trial results and not observed power.
The registry record does not report the trial’s own sample-size justification. It also does not report a single comparison for the primary outcome, and the record notes that the outcome has several categories or time points and is not reduced to one comparison. As a result, the planning illustration should not be treated as a design calculation for this multi-arm sequential study. Its assumptions do not establish that the trial was sized to detect a particular safety difference, or that it had a particular probability of detecting an effect.
What is not documented?
The statistical analysis plan, any interim analyses, handling of repeated events, missing-data methods, analysis populations and rules for determining relatedness are not reported in the registry record. The registry does not provide a model specification, adjustment variables, or a method for accounting for multiple outcomes or comparisons. Those omissions matter because the endpoint includes event categories and a follow-up period, while the arms vary in dose and adjuvant.
General statistical context: prespecification helps readers distinguish planned analyses from analyses chosen after observing results. Clear population definitions also show which randomized participants are included in each analysis. Without these details, readers should avoid attributing a particular statistical method or interpretation to the study team. The posted material supports a descriptive reading of the displayed safety counts, but does not permit reconstruction of a full inferential analysis.
10. Multiplicity, Missing Data and Analysis Populations
The study has several outcomes of interest. The registry lists Grade 1 and 2 adverse events, transmission-reducing activity and anti-6C antibody quantities as secondary outcomes, in addition to the primary safety endpoint. It also lists five outcome measures. The record does not describe a multiplicity strategy for assessing several endpoints, categories, time points or comparisons.
General statistical context: when many outcomes or comparisons are examined, the chance of seeing an apparently notable result by chance can increase. Prespecified hierarchies, adjusted thresholds or a clear distinction between confirmatory and exploratory outcomes can help readers understand that issue. The registry record does not report whether any such approach was used, so no adjustment or absence of adjustment should be assumed.
The number of analyses is listed as 0, and the primary outcome is not reduced to one comparison because it has several categories or time points. This means there is no posted analysis set from which to evaluate how multiple testing was handled. Numerical findings for the secondary outcomes are not reported in the registry record.
Missing-data methods and analysis populations are also not reported in the registry record. The record gives enrollment and arm descriptions, but does not state how many participants completed follow-up, whether all randomized participants were included in each outcome summary, or how incomplete observations were handled. It does not report an intention-to-treat, per-protocol or safety population definition. General statistical context: these definitions affect which participants contribute to each estimate and how missing outcomes may affect interpretation. Without them, readers cannot determine whether the displayed counts reflect all randomized participants, participants who received vaccination, or another defined population.
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 |
|---|---|---|---|
| 1A 30μg R0.6C Alhydrogel | 0 | 3 | 0.0% |
| 1B 30μg R0.6C Alhydrogel + Matrix M1 | 0 | 3 | 0.0% |
| 2A 30μg R0.6C Alhydrogel | 0 | 5 | 0.0% |
| 2B 30μg R0.6C Alhydrogel + Matrix M1 | 0 | 5 | 0.0% |
| 3A 100μg R0.6C Alhydrogel | 0 | 3 | 0.0% |
| 3B 100μg R0.6C Alhydrogel + Matrix M1 | 0 | 3 | 0.0% |
| 4A 100μg R0.6C Alhydrogel | 0 | 5 | 0.0% |
| 4B 100μg R0.6C Alhydrogel + Matrix M1 | 0 | 5 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| 1A 30μg R0.6C Alhydrogel | 0 of 3 |
| 1B 30μg R0.6C Alhydrogel + Matrix M1 | 0 of 3 |
| 2A 30μg R0.6C Alhydrogel | 0 of 5 |
| 2B 30μg R0.6C Alhydrogel + Matrix M1 | 0 of 5 |
| 3A 100μg R0.6C Alhydrogel | 0 of 3 |
| 3B 100μg R0.6C Alhydrogel + Matrix M1 | 0 of 3 |
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 |
|---|---|
| 1A 30μg R0.6C Alhydrogel | 3 of 3 |
| 1B 30μg R0.6C Alhydrogel + Matrix M1 | 3 of 3 |
| 2A 30μg R0.6C Alhydrogel | 5 of 5 |
| 2B 30μg R0.6C Alhydrogel + Matrix M1 | 5 of 5 |
| 3A 100μg R0.6C Alhydrogel | 3 of 3 |
| 3B 100μg R0.6C Alhydrogel + Matrix M1 | 3 of 3 |
Most frequent non-serious adverse event terms
| Event term | Organ system | 1A 30μg R0.6C Alhydrogel | 1B 30μg R0.6C Alhydrogel + Matrix M1 | 2A 30μg R0.6C Alhydrogel | 2B 30μg R0.6C Alhydrogel + Matrix M1 | 3A 100μg R0.6C Alhydrogel | 3B 100μg R0.6C Alhydrogel + Matrix M1 |
|---|---|---|---|---|---|---|---|
| Pain at injection site | Skin and subcutaneous tissue disorders | 3 of 3 | 2 of 3 | 5 of 5 | 4 of 5 | 3 of 3 | 3 of 3 |
| Headache | General disorders | 1 of 3 | 2 of 3 | 4 of 5 | 4 of 5 | 2 of 3 | 2 of 3 |
| Common cold | Infections and infestations | 1 of 3 | 2 of 3 | 4 of 5 | 4 of 5 | 2 of 3 | 2 of 3 |
| Itching at injection site | Skin and subcutaneous tissue disorders | 0 of 3 | 2 of 3 | 2 of 5 | 4 of 5 | 1 of 3 | 3 of 3 |
| Erythema at injection site | Skin and subcutaneous tissue disorders | 0 of 3 | 1 of 3 | 2 of 5 | 5 of 5 | 1 of 3 | 3 of 3 |
| COVID-19 | Infections and infestations | 0 of 3 | 1 of 3 | 2 of 5 | 4 of 5 | 2 of 3 | 3 of 3 |
| Induration at injection site | Skin and subcutaneous tissue disorders | 1 of 3 | 1 of 3 | 0 of 5 | 4 of 5 | 1 of 3 | 3 of 3 |
| Myalgia | Musculoskeletal and connective tissue disorders | 1 of 3 | 1 of 3 | 1 of 5 | 3 of 5 | 0 of 3 | 1 of 3 |
| Tenderness at injection site | Skin and subcutaneous tissue disorders | 2 of 3 | 1 of 3 | 1 of 5 | 2 of 5 | 0 of 3 | 1 of 3 |
| Fatigue | General disorders | 0 of 3 | 0 of 3 | 2 of 5 | 2 of 5 | 1 of 3 | 1 of 3 |
In each of the eight arm rows, the serious-adverse-event field lists zero participants affected, and the death field lists zero. The other-adverse-event field lists 3 affected participants in arms with 3 at risk and 5 affected participants in arms with 5 at risk. These are participant-level entries in the adverse-event table, not a report of the number of individual events.
The primary outcome is defined more narrowly: it counts serious adverse events and solicited or unsolicited Grade 3 adverse events considered possibly, probably or definitely related to vaccine, during the stated period. The table does not identify the grade or relatedness of its “other” events, and it does not show event-level counts. It is therefore not possible to determine from these entries how many participants experienced the primary composite outcome.
General statistical context: zero observed serious events in a small group does not prove that the underlying risk is zero. It indicates only that the table records no such affected participants in that group. The precision of a risk estimate depends on the amount and completeness of follow-up, among other factors. The registry does not report confidence intervals for these safety figures, nor does it provide enough detail to assess follow-up completeness or event adjudication.
12. What the Result Does, and Does Not, Mean
The registry record describes a completed phase I study of R0.6C vaccine in healthy malaria-naïve adults. It documents a randomized, open-label, sequential dose-escalation design with arms that vary by dose and adjuvant combination. The posted adverse-event table records zero participants with serious adverse events and zero deaths in each listed arm. Those entries are descriptive observations, not proof that serious events cannot occur or a precise estimate of their likelihood.
The other adverse-event field shows affected-participant counts, but it does not supply the severity, relatedness or event-level information needed to map those counts onto the primary endpoint definition. The primary outcome’s full event count is not reported in the registry record as a single analysis result. No primary comparison, effect estimate, confidence interval or p-value is reported.
The study’s stated aims include transmission-reducing activity and antibody quantities. The registry lists these as secondary outcomes, but numerical findings for them are not reported. Therefore, this page cannot quantify transmission-reducing activity, compare activity between adjuvant combinations, or describe antibody responses from the available record.
General statistical context: a small early-stage study can provide initial descriptive information, but precision depends on the amount of information available and the number of events observed. A lack of observed serious events in these arm summaries is not the same as a formal demonstration of equivalence or absence of risk. Nor do the posted results establish a comparative benefit. The record’s design and posted outcome information support a cautious account of the study structure and displayed safety counts, with substantial uncertainty around broader interpretations.
What remains unknown includes the detailed analysis plan, participant flow, missing-data handling, outcome-specific estimates and inferential comparisons. These are not reported in the registry record, so conclusions should remain bounded by the information actually displayed.
13. Why This Trial Matters Statistically
This trial illustrates a common challenge in reading early-stage clinical studies: the registry can describe several treatment groups and a clearly worded safety outcome without presenting a single analysis that answers a simple between-group question. Here, the arms vary by dose and adjuvant, the design is sequential, and the record notes that the primary outcome has several categories or time points rather than one reduced comparison.
That distinction is statistically important. A list of group-level safety counts is not necessarily an estimate of a treatment contrast. To interpret a contrast, readers need a defined comparison, an analysis population and a method for summarizing uncertainty. Those are not reported for the primary outcome in this record. The adverse-event table is useful as a descriptive display, but its participant-level affected counts should not be conflated with the event-count endpoint.
The study also shows why endpoint definitions and table labels must be read together. The primary outcome specifies seriousness, Grade 3 severity, vaccine relatedness and a follow-up period. The available safety table separates serious events from other adverse events but does not provide the detail needed to identify which entries meet the complete primary definition. That limitation prevents a direct reconstruction of the endpoint result.
General statistical context: a planning illustration based on an observed effect is not the same as a prospectively justified sample size, and neither is a measure of observed power. Keeping those concepts distinct helps prevent design assumptions from being mistaken for trial findings. In this record, the sample-size illustration’s assumptions are stated, but the trial’s own sample-size justification is not reported.
Overall, the trial matters statistically as an example of why design, endpoint definition, population accounting and reporting completeness all shape what can be inferred. The posted results support description, but not a quantified comparative 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.
Several limitations specific to this record constrain interpretation. First, the posted safety table does not provide an event-level breakdown or a direct numerical result for the primary endpoint as defined. The table’s other-adverse-event entries do not state grade or relatedness, while the primary endpoint requires specified severity and attribution criteria. The two displays therefore cannot be assumed to represent the same outcome.
Second, the record does not report the number of participants completing the stated follow-up, the completeness of outcome collection, or how missing observations were handled. Enrollment and planned arm descriptions do not establish the analysis population for each outcome. Participant flow and analysis-population definitions are not reported in the registry record.
Third, the study includes multiple dose and adjuvant combinations within a sequential design, but the registry does not report escalation rules, a single primary comparison or a statistical model. The record notes that the primary outcome has several categories or time points and is not reduced to one comparison. Consequently, the posted material does not support a direct comparative estimate across the groups.
Fourth, numerical results for the listed transmission-reducing activity and anti-6C antibody outcomes are not reported in the registry record. The record therefore cannot support a statistical assessment of those stated aims. Details of event grading, relatedness assessment, randomization procedure, multiplicity handling and any interim analyses are also not reported in the registry record.
Finally, this is a single-site study in healthy malaria-naïve adults. The registry does not describe evidence from other populations or settings. These design and reporting features limit the scope of what can be inferred from the available record, independently of the direction of any unreported findings.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Safety and Efficacy of R0.6C Vaccine — NCT04862416.
- Registry record last updated 2025-03-05; status last verified 2025-02.
- Results first posted 2025-03-05.
- Data retrieved from ClinicalTrials.gov on 2026-11-09.
- Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.
Continue through the Clinical Biostats statistical pathway
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18. Record Summary
The registry describes NCT04862416, titled “Safety and Efficacy of R0.6C Vaccine,” as a completed, randomized, open-label phase I study. It is a first-in-human, single-site, sequential dose-escalation study in healthy malaria-naïve adults in the Netherlands. Enrollment is 32; the recorded start date is 2021-05-17 and primary completion date is 2022-06-29.
The arms vary by 30 ug or 100 ug R0.6C with Alhydrogel alone or combined with Matrix M1. The descriptions specify four vaccinations on days 0, 28, 56 and 168. The primary outcome concerns serious and related Grade 3 adverse events over the stated period following immunization.
The posted safety table lists zero serious-adverse-event-affected participants and zero deaths in each arm. It also lists participant counts for other adverse events, without enough detail to identify the primary endpoint events. No primary-outcome analysis estimate is reported. Numerical results for the listed transmission-reducing activity and antibody outcomes are not reported in the registry record.