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 Evaluate the Safety and Tolerability, for Nirsevimab in Immunocompromised Children (NCT04484935), a na phase 2 study. The primary outcome is Number of Participants With Treatment-Emergent Adverse Events (TEAEs), Treatment-Emergent Serious AEs (TESAEs), AEs of Special Interest (AESIs), and New Onset Chronic Disease (NOCDs).
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT04484935 |
| Phase | Phase 2 |
| Condition | RSV Infection |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 100 |
| Arms in the primary outcome | n/a |
| Lead sponsor | AstraZeneca |
| Results posted | Yes |
2. Clinical Question
Population
Immunocompromised children aged ≤ 24 months at the time of dosing were eligible. The study aimed to enroll approximately 100 participants; the registry lists enrollment of 100. The as-treated population included participants who were enrolled and received any dose of nirsevimab.
Intervention
Participants received nirsevimab as a single dose. The registry describes dosing in relation to RSV season, including 50 mg and 100 mg in the first season and 200 mg in the second season. The safety groups are titled Nirsevimab 50 mg/100 mg and Nirsevimab 200 mg.
Comparator
There was no control group. The study was open-label, uncontrolled, and single-group; allocation is listed as not applicable. The dose groups are not a like-for-like control comparison, so differences between their counts cannot establish a treatment effect.
Primary question
The primary endpoint counted participants with treatment-emergent adverse events, treatment-emergent serious adverse events, adverse events of special interest, and new onset chronic diseases. The study also assessed serum concentrations, antidrug antibodies, medically attended RSV lower respiratory tract infection, and hospitalizations.
The study, NCT04484935, was a Phase 2 safety, tolerability, and pharmacokinetic evaluation in a population described as immunocompromised children. Its brief summary also names efficacy as an objective, but the primary endpoint itself is safety-focused. The main interpretive question is therefore descriptive: what adverse-event counts and other outcomes were recorded following nirsevimab administration, and how much can those observations establish without a concurrent control group?
The registry lists a follow-up period of approximately one year after dosing. The primary safety collection window ran from the first dose on Day 1 through 360 days post dose. These time frames help define which events could be captured, but they do not show that every participant contributed the same amount of observation time or that all outcomes were fully observed.
3. Trial Design
This was a Phase 2, open-label, uncontrolled, single-dose study of nirsevimab. The registry lists the study as completed and records enrollment of 100. Its brief summary describes approximately 100 participants and follow-up for approximately one year after dosing. The study start date was 2020-08-19, and the primary completion date was 2023-02-17.
Because the study had no control group, its main contribution is descriptive: it records safety and other outcomes among participants who received nirsevimab. Open-label means the study was not masked. The registry does not report a randomized allocation scheme, and allocation is listed as not applicable. The dose groups cannot be treated as randomized comparison arms or as a like-for-like control comparison.
The intervention was nirsevimab. The arm descriptions refer to doses of 50 mg, 100 mg, and 200 mg in relation to RSV season. The posted safety groups are titled Nirsevimab 50 mg/100 mg and Nirsevimab 200 mg. The registry record does not explain how participants were assigned among these dose groups, so the group labels alone should not be used to infer an assignment process.
The primary endpoint counted participants with treatment-emergent adverse events, treatment-emergent serious adverse events, adverse events of special interest, and new onset chronic diseases. Secondary outcomes included serum concentrations of nirsevimab, antidrug antibody responses, and medically attended RSV lower respiratory tract infection and hospitalizations.
The registry record does not report a protocol-level statistical analysis plan, sample-size justification, or interim analysis plan. The planning assumptions attached to the sample-size illustrations are not evidence that the trial was designed as a two-arm efficacy comparison. The stated assumptions describe an illustration based on an observed effect, with equal allocation, a two-sided significance level of 0.05, and a normal approximation; they do not establish the study’s original design rationale.
4. Participant Flow and Accounting
The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.
Before assignment: This study consisted of a screening period (Visit 1, Day -30 to Day -1); a dosing visit (Visit 2, Day 1) where participants received treatment with nirsevimab and a follow-up period up to Day 361 (Visit 3 to 7). A total of 100 children were enrolled in this study.
Overall Study
| Stage | Nirsevimab 50 mg/100 mg | Nirsevimab 200 mg |
|---|---|---|
| STARTED | 48 | 52 |
| COMPLETED | 45 | 49 |
| NOT COMPLETED | 3 | 3 |
Reasons for not completing this period:
| Reason | Nirsevimab 50 mg/100 mg | Nirsevimab 200 mg |
|---|---|---|
| Other | 0 | 1 |
| Withdrawal by parent/guardian | 0 | 1 |
| Lost to Follow-up | 1 | 0 |
| Death | 2 | 1 |
Analysis population for the primary outcome, as defined in the registry: The As-treated population consisted of all participants who were enrolled and received any dose of nirsevimab.
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: The As-treated population consisted of all participants who were enrolled and received any dose of nirsevimab.
| Characteristic | Unit | Nirsevimab 50 mg/100 mg | Nirsevimab 200 mg | Total |
|---|---|---|---|---|
| Participants analysed | 48 | 52 | 100 | |
| Age, Continuous | months | 7.64 (SD 3.270) | 17.90 (SD 3.748) | 12.97 (SD 6.232) |
| Sex: Female, Male: Female | Participants | 18 | 17 | 35 |
| Sex: Female, Male: Male | Participants | 30 | 35 | 65 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 4 | 3 | 7 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 44 | 49 | 93 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 0 | 0 | 0 |
| Race/Ethnicity, Customized: Asian | Participants | 16 | 12 | 28 |
| Race/Ethnicity, Customized: American Indian or Alaskan Native | Participants | 1 | 0 | 1 |
| Race/Ethnicity, Customized: Black or African American | Participants | 9 | 11 | 20 |
| Race/Ethnicity, Customized: Native Hawaiian or Other Pacific Islander | Participants | 0 | 0 | 0 |
| Race/Ethnicity, Customized: White | Participants | 20 | 25 | 45 |
| Race/Ethnicity, Customized: Other | Participants | 2 | 2 | 4 |
| Race/Ethnicity, Customized: Multiple categories checked | Participants | 0 | 2 | 2 |
6. Primary Endpoint
The registry lists the primary outcome as Number of Participants With Treatment-Emergent Adverse Events (TEAEs), Treatment-Emergent Serious AEs (TESAEs), AEs of Special Interest (AESIs), and New Onset Chronic Disease (NOCDs), measured over TEAEs were collected from the first dose administration (Day 1) up to 360 days post dose.
| Element | Registry entry |
|---|---|
| Result type | Count Of Participants |
| Measure of spread | not applicable |
| Unit | Participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint was the number of participants with treatment-emergent adverse events, treatment-emergent serious adverse events, adverse events of special interest, and new onset chronic diseases. It is a participant-count endpoint: it records whether participants experienced events in the specified categories rather than measuring event severity on a continuous scale or counting every occurrence as a separate participant.
A treatment-emergent adverse event was defined as an untoward medical occurrence whose onset followed nirsevimab administration and occurred within 360 days post dose. The definition did not require that the event be considered related to treatment. A serious adverse event included events meeting specified seriousness criteria, such as death, a life-threatening event, inpatient hospitalization, persistent or significant disability or incapacity, a congenital abnormality, or another medically significant event.
Adverse events of special interest covered immediate hypersensitivity, including anaphylaxis, thrombocytopenia, and immune complex disease, based on investigator assessment and preferred-term codes. A new onset chronic disease was a newly diagnosed medical condition of a chronic, ongoing nature after treatment.
Safety endpoints of this kind are used to describe events observed during a defined follow-up period. In a single-group study, they can characterize what was reported among treated participants, but they cannot by themselves determine whether an event was caused by treatment or occurred more often than it would have without treatment. The registry record does not provide a separate primary-endpoint result for each of the listed event categories.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The posted safety counts are descriptive observations from a study without a control group. In the Nirsevimab 50 mg/100 mg group, the registry lists 48 participants at risk for the serious-event count and 12 affected; it lists 48 at risk for other adverse events and 35 affected, with 2 deaths. In the Nirsevimab 200 mg group, it lists 52 at risk for the serious-event count and 20 affected; it lists 52 at risk for other adverse events and 41 affected, with 1 death. These figures describe the recorded groups; they do not establish that dose caused differences between them.
The study was open-label, and the registry identifies no control group. Without a concurrent comparison group, the counts cannot distinguish events associated with the underlying conditions, background illness, or other circumstances from events attributable to nirsevimab. The study design also does not support a causal comparison between the dose groups. The registry record does not report how participants came to be in each group, and the listed groups are not described as randomized.
Serious adverse event terms listed in the record include pneumonia at 7.7%, lower respiratory tract infection at 5.8%, COVID-19 at 5.8%, rhinovirus infection at 4.2%, viral diarrhoea at 4.2%, and pyrexia at 4.2%. These percentages are registry descriptions of reported serious-event terms. They should not be interpreted as comparative risks because there is no control group, and the registry record does not report a comparative analysis for these terms.
The primary endpoint combined several safety categories. The registry’s endpoint description defines those categories, while the posted safety counts are grouped into serious and other adverse events. The record does not provide separate participant counts for every component of the primary endpoint, nor does it report confidence intervals or statistical tests for these counts. This limits how precisely the results can be quantified and prevents an inferential claim about differences between groups.
Counts are also sensitive to the number of participants observed and to the duration and completeness of follow-up. The record gives a planned follow-up of approximately one year and a safety collection window through 360 days post dose, but does not report participant-level follow-up completeness in the information available. A participant count does not show the total number of events, their timing, or how long participants remained under observation.
The outcomes include safety, pharmacokinetics, antidrug antibodies, and RSV illness. The registry lists four outcome measures and zero analyses. A measure being listed does not establish that its result or a statistical analysis was posted. Interpretation should therefore remain anchored to the reported counts and definitions rather than assuming that all study objectives have corresponding numerical results in the registry record.
9. Statistical Methods Explained
Several statistical ideas help clarify what the reported counts can and cannot establish. The primary outcome is a count of participants with events. For each participant, this type of measure generally records whether an event occurred within the defined period. It is different from a count of all event episodes: one participant with repeated events may still contribute as one affected participant to a participant-count outcome. The registry defines the endpoint as a participant count, but it does not report a complete breakdown of each primary-endpoint component.
What does a participant count describe?
A participant count is directly interpretable as the number of people recorded with an event in a defined group. The accompanying at-risk count identifies the group size used for that event category. These counts are useful for describing the observed safety experience. They do not, on their own, express uncertainty around the underlying event frequency. A confidence interval is a general statistical tool for representing uncertainty around an estimate; no confidence intervals for the posted safety counts are reported in the registry information.
Counts also depend on how events are defined and collected. The treatment-emergent window in this study began after the first dose and extended through 360 days post dose. Seriousness was defined by clinical criteria, while the special-interest events had their own specified definitions. Such definitions make event classification more consistent, but they do not eliminate differences in assessment or reporting. The study was open-label, and the registry record does not report masking of participants or investigators.
Why does the single-group design matter?
In a controlled comparison, outcomes in a treatment group can be interpreted alongside outcomes under a specified comparator, subject to the design and analysis. Here, there was no control group. The observed counts therefore describe events among participants who received nirsevimab, not the contrast between treatment and no treatment. General statistical reasoning is that causal interpretation requires a credible comparison and assumptions about how groups differ. The registry record does not provide a randomized comparison that would support those assumptions.
The two listed dose groups do not supply an equivalent substitute for a control group. Their labels identify nirsevimab dose categories, but the record does not report random assignment between them. Participant characteristics, clinical circumstances, or observation patterns could differ between groups. A numerical difference between their counts is not, by itself, evidence of a dose effect.
What do uncertainty measures add?
General statistical inference distinguishes the observed data from uncertainty about a broader underlying process. A confidence interval communicates a range of values compatible with the data under a specified method and assumptions. A hypothesis test evaluates data against a defined statistical model and null hypothesis. Neither measure can correct for the absence of a suitable control group or for unreported aspects of data collection. The registry record does not report confidence intervals, p-values, or a comparative hypothesis test for the safety figures.
For event counts, models may also need to account for how much observation time participants contribute. When event rates vary more than a simple model expects, over-dispersion can make standard uncertainty estimates too narrow; this is a general consideration, not a claim about this study. The registry record does not report an event-rate model, person-time analysis, or an over-dispersion assessment. The posted endpoint is defined as participants with events, and the displayed safety information does not establish that a rate model was used.
How should planning illustrations be read?
The sample-size illustrations use a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. They frame the effect to detect as a stated fraction of the observed effect. The record describes these as planning illustrations computed from the observed effect, not as the trial’s own design. They should not be interpreted as evidence that the study had a particular power for its observed outcomes. Sample-size illustrations are prospective planning calculations under stated assumptions; they are not observed power, and they do not alter the descriptive nature of this uncontrolled study.
The record does not report the original sample-size justification or a statistical analysis plan. It also does not report the numerical sample-size results in the information summarized in the registry record. Consequently, no conclusion about the adequacy of the planned enrollment for a specific safety or efficacy objective can be drawn from the available information.
What does the analysis population mean?
The primary endpoint identifies the as-treated population as participants who were enrolled and received any dose of nirsevimab. This population definition clarifies who is intended to contribute to the safety analysis. It is distinct from an intention-to-treat population, which is commonly defined using randomized assignment; this study was not randomized. The registry record does not report the number of participants included in each analysis population beyond the group-specific safety counts or describe how missing observations were handled.
10. Multiplicity, Missing Data and Analysis Populations
The study included several outcomes: the primary safety endpoint and secondary measures covering serum concentrations, antidrug antibodies, medically attended RSV lower respiratory tract infection, and hospitalizations. When a study assesses multiple outcomes, the chance of at least one apparently notable result can increase if each is tested separately. General statistical approaches may control this multiplicity through a prespecified hierarchy or adjustment. The registry record does not report a multiplicity strategy, a hierarchy for interpreting outcomes, or statistical tests across these measures. It lists four outcome measures and zero analyses.
The primary endpoint itself includes several categories: treatment-emergent adverse events, serious adverse events, adverse events of special interest, and new onset chronic diseases. The registry record supplies definitions for these categories, but does not report separate primary-endpoint results for each component in the information. It is therefore not possible to assess how a combined endpoint was constructed or whether any component drove an overall result.
The as-treated population consists of enrolled participants who received any dose. The registry record does not report missing-data methods, how participants with incomplete follow-up were handled, or whether all enrolled participants contributed to each outcome. It also does not report reasons for missing outcome data or the completeness of the planned follow-up.
These omissions matter because participant counts depend on both outcome ascertainment and the population included in each analysis. Without a reported analysis plan and missing-data accounting, the robustness of the counts to incomplete observation cannot be evaluated. No assumptions about imputation, censoring, or interim analyses can be made from the registry information.
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 |
|---|---|---|---|
| Nirsevimab 50 mg/100 mg | 12 | 48 | 25.0% |
| Nirsevimab 200 mg | 20 | 52 | 38.5% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Nirsevimab 50 mg/100 mg | 2 of 48 |
| Nirsevimab 200 mg | 1 of 52 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 5% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Nirsevimab 50 mg/100 mg | 35 of 48 |
| Nirsevimab 200 mg | 41 of 52 |
Most frequent serious adverse event terms
| Event term | Organ system | Nirsevimab 50 mg/100 mg | Nirsevimab 200 mg |
|---|---|---|---|
| Pneumonia | Infections and infestations | 1 of 48 | 4 of 52 |
| Lower respiratory tract infection | Infections and infestations | 1 of 48 | 3 of 52 |
| COVID-19 | Infections and infestations | 1 of 48 | 3 of 52 |
| Pyrexia | General disorders | 2 of 48 | 1 of 52 |
| Klebsiella sepsis | Infections and infestations | 0 of 48 | 2 of 52 |
| Thrombocytopenia | Blood and lymphatic system disorders | 0 of 48 | 2 of 52 |
| Rhinovirus infection | Infections and infestations | 2 of 48 | 0 of 52 |
| Viral diarrhoea | Infections and infestations | 2 of 48 | 0 of 52 |
| Nephrotic syndrome | Renal and urinary disorders | 0 of 48 | 2 of 52 |
| Febrile neutropenia | Blood and lymphatic system disorders | 0 of 48 | 2 of 52 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Nirsevimab 50 mg/100 mg | Nirsevimab 200 mg |
|---|---|---|---|
| Upper respiratory tract infection | Infections and infestations | 18 of 48 | 18 of 52 |
| Pyrexia | General disorders | 13 of 48 | 13 of 52 |
| Vomiting | Gastrointestinal disorders | 8 of 48 | 13 of 52 |
| Diarrhoea | Gastrointestinal disorders | 8 of 48 | 10 of 52 |
| COVID-19 | Infections and infestations | 4 of 48 | 12 of 52 |
| Rhinorrhoea | Respiratory, thoracic and mediastinal disorders | 6 of 48 | 7 of 52 |
| Dermatitis diaper | Skin and subcutaneous tissue disorders | 5 of 48 | 8 of 52 |
| Nasopharyngitis | Infections and infestations | 6 of 48 | 6 of 52 |
| Otitis media | Infections and infestations | 5 of 48 | 6 of 52 |
| Cough | Respiratory, thoracic and mediastinal disorders | 6 of 48 | 4 of 52 |
Serious events with the highest arm-level rate: pneumonia (7.7%), lower respiratory tract infection (5.8%), covid-19 (5.8%), rhinovirus infection (4.2%), viral diarrhoea (4.2%).
The registry lists safety counts for two nirsevimab groups. In the Nirsevimab 50 mg/100 mg group, 12 participants among 48 at risk were affected in the serious-event category, and 35 among 48 were affected in the other-adverse-event category; 2 deaths are listed. In the Nirsevimab 200 mg group, 20 among 52 were affected in the serious-event category, and 41 among 52 in the other-adverse-event category; 1 death is listed. These are counts, not estimates from a controlled comparison.
The serious-event term list includes pneumonia at 7.7%, lower respiratory tract infection at 5.8%, COVID-19 at 5.8%, rhinovirus infection at 4.2%, viral diarrhoea at 4.2%, and pyrexia at 4.2%. The registry record does not clarify in this information whether these percentages refer to unique participants across all terms or how overlapping terms were handled. They should be read as reported term-level summaries, not added together or treated as mutually exclusive categories.
Seriousness is a defined regulatory classification and does not by itself establish that an event was caused by treatment. The no-control design also means these counts cannot be contrasted with an untreated group. The registry record does not report event-level timing, causal attribution, or a comparative analysis for the listed events.
12. What the Result Does, and Does Not, Mean
The study documents safety observations after nirsevimab administration in immunocompromised children aged ≤ 24 months. Its primary endpoint was designed to count participants with treatment-emergent adverse events and specified safety-event categories over a defined period. The registry also posts group-level serious and other adverse-event counts, deaths, and selected serious-event terms. These are descriptive findings from the participants included in those groups.
They do not establish that nirsevimab caused any particular event. The endpoint definition explicitly includes adverse events whether or not investigators considered them related to treatment. In addition, there is no control group against which to compare the observed event counts. The two nirsevimab groups are not a like-for-like control comparison, and the registry does not report randomized allocation between them. Therefore, apparent differences between their counts cannot establish that one dose caused more or fewer events.
The study’s stated objectives also included pharmacokinetics, antidrug antibodies, and efficacy, while secondary outcomes included medically attended RSV lower respiratory tract infection and hospitalizations. The registry record lists these outcome areas but the information does not provide numerical results for them. Their presence as objectives should not be mistaken for evidence of a particular result.
Precision is also limited by the absence of reported confidence intervals or comparative tests for the safety counts. Counts describe what was recorded in the observed groups; they do not quantify uncertainty around an underlying event frequency. The registry record does not report follow-up completeness or methods for handling missing observations, which further limits assessment of how comprehensively the outcomes were captured.
In short, the record characterizes a single-group safety study and identifies events observed among treated participants. It does not establish a causal treatment effect, a comparative safety profile, or an efficacy conclusion. Such interpretations would require results and comparisons that are not reported in the registry record.
13. Why This Trial Matters Statistically
This trial is statistically informative as an example of the distinction between describing outcomes and estimating comparative effects. A single-group study can document the types and counts of events observed after treatment in a defined population. That descriptive role is meaningful, especially when the population of interest is clearly specified and follow-up windows are defined. The registry identifies immunocompromised children aged ≤ 24 months and describes a safety window through 360 days post dose.
At the same time, the design determines the scope of inference. Without a control group, event counts cannot separate treatment-related effects from background events or the circumstances of the participants. Listing two dose groups does not create a valid controlled comparison when the record does not report random allocation and labels both groups as receiving nirsevimab. This is a central statistical point: the presence of multiple group counts is not equivalent to a comparative design.
The endpoint’s focus on participants with events also illustrates the importance of defining the estimand and measurement. A participant count is not the same as an event count or an event rate. It communicates how many people were recorded with an event category, but not the number of repeated episodes or each participant’s time under observation. Clear endpoint definitions and complete follow-up information are important for interpreting such summaries.
Finally, the record distinguishes outcome listing from analysis reporting. It identifies safety, pharmacokinetic, antidrug antibody, and RSV illness outcomes, but lists zero analyses. The absence of reported inferential methods, missing-data handling, and multiplicity procedures limits conclusions beyond the descriptive counts. These features make the study useful for understanding what the registry record can describe, while underscoring why design and analysis details are needed before making broader statistical claims.
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 study was open-label and uncontrolled, so there is no concurrent control group to contextualize the observed events. The registry specifically cautions that the dose groups are not a like-for-like control comparison. The record does not describe how participants entered the 50 mg/100 mg and 200 mg groups, so dose-group differences should not be interpreted causally.
The primary endpoint combines several safety categories, but the information summarized in the record does not give separate participant counts for each component. The posted safety counts do not supply a complete account of every primary-endpoint category. The record also does not report confidence intervals, comparative tests, or a statistical model for these outcomes.
Follow-up was intended to last approximately one year, and the primary safety window extended through 360 days post dose. The registry information does not report follow-up completeness, the number of participants with missing outcomes, or methods for handling incomplete observation. It also does not provide participant-level event timing or a full account of event attribution.
The registry lists secondary outcome areas but does not provide numerical results for each in the information. It lists four outcome measures and zero analyses. The protocol-level statistical analysis plan, multiplicity strategy, interim analysis plan, and original sample-size justification are not reported in the registry record. The sample-size illustrations use planning assumptions and are not a substitute for those missing design details or for observed comparative evidence.
Finally, these limitations concern interpretation of the registry record and do not imply that unreported procedures were absent from the underlying study. They indicate that those procedures and results are not reported in the registry record, so they cannot be evaluated from the posted information.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Evaluate the Safety and Tolerability, for Nirsevimab in Immunocompromised Children — NCT04484935.
- Registry record last updated 2023-11-15; status last verified 2023-10.
- Results first posted 2023-11-15.
- Data retrieved from ClinicalTrials.gov on 2026-11-09.
- Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.
Continue through the Clinical Biostats statistical pathway
Use this trial's endpoint as a starting point for deeper study of effect measures, confidence intervals, and sample-size planning.
18. Record Summary
NCT04484935 is a completed Phase 2, open-label, uncontrolled, single-dose study of nirsevimab in immunocompromised children aged ≤ 24 months. The registry lists enrollment of 100 and a primary completion date of 2023-02-17. The primary endpoint counted participants with treatment-emergent adverse events, serious adverse events, adverse events of special interest, and new onset chronic diseases, with safety collection through 360 days post dose.
Posted safety counts describe the Nirsevimab 50 mg/100 mg and Nirsevimab 200 mg groups, including serious and other adverse events and deaths. The study also listed pharmacokinetic, antidrug antibody, and RSV illness outcomes. Because there was no control group and no randomized comparison, the counts are descriptive rather than estimates of comparative treatment effects. The registry record does not report a statistical analysis plan, missing-data methods, or comparative analyses.