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 Phase 2 Study of Belimumab Administered Subcutaneously to Subjects With Systemic Lupus Erythematosus (SLE) (NCT00732940), a randomized phase 2 study. The primary outcome is Evaluation of the Number of Participants Who Experienced Adverse Events (AEs) During the 24 Week Period..
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00732940 |
| Phase | Phase 2 |
| Condition | Systemic Lupus Erythematosus |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 56 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Human Genome Sciences Inc. |
| Results posted | Yes |
2. Clinical Question
Population
Participants with systemic lupus erythematosus (SLE) were enrolled. The registry record reports enrollment of 56 participants. Further eligibility details and the characteristics of the enrolled population are not reported in the registry record.
Intervention
One group received subcutaneous belimumab on a three-times-weekly schedule. The schedule began with 200 mg on days 0, 2, and 4, followed by 100 mg three times a week through the Week 24 evaluation. An option to continue at the same dose through a 144 week continuation period was described.
Comparator
The other group received 100 mg of subcutaneous belimumab every other week. The schedule began on days 0, 7, and 14, then continued every other week through the Week 24 evaluation. An option to continue at the same dose through a 144 week continuation period was described. Both groups received belimumab; there was no placebo or untreated comparison group in the listed arms.
Primary question
The stated primary outcome concerns the percentage of participants who experienced adverse events during up to 24 weeks. This frames the main question as a safety and tolerability comparison between the two dosing schedules. The registry record points to the adverse events results but does not report a separate overall result for this primary endpoint.
3. Trial Design
This was a phase 2, randomized, open-label, parallel-group study of subcutaneous belimumab in people with systemic lupus erythematosus. The registry record reports enrollment of 56 participants and lists two dosing schedules, both using belimumab. The study is marked terminated. The reason for termination is not reported in the registry record.
One group received 100 mg every other week, with initial doses on days 0, 7, and 14. The other received 200 mg on days 0, 2, and 4, followed by 100 mg three times weekly. Both schedules were described through the Week 24 final evaluation, with an option to continue the same dosing through a 144 week continuation period. Whether participants entered or completed that continuation period is not reported in the registry record.
Open-label means participants and study personnel were not masked to the assigned schedule. Randomization means allocation was intended to occur by chance, but the method used to generate or conceal the allocation sequence is not reported in the registry record. The listed design is parallel-group: the schedules were assigned to separate groups rather than being described as successive treatments for each participant.
The primary outcome was adverse-event occurrence during up to 24 weeks. Listed secondary outcomes include serum belimumab concentration levels over 24 weeks, changes in immunoglobulin measures at Week 24, and change in Physician’s Global Assessment score at Week 24. Although these outcomes are named, their numerical results are not reported in the registry record. The record does not describe eligibility criteria, baseline characteristics, or the planned statistical analysis in detail.
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 | Belimumab SC Q2WKS | Belimumab SC 3X/WK |
|---|---|---|
| STARTED | 28 | 28 |
| COMPLETED | 26 | 25 |
| NOT COMPLETED | 2 | 3 |
Reasons for not completing this period:
| Reason | Belimumab SC Q2WKS | Belimumab SC 3X/WK |
|---|---|---|
| Withdrawal by Subject | 1 | 2 |
| Adverse Event | 0 | 1 |
| Lost to Follow-up | 1 | 0 |
Analysis population for the primary outcome, as defined in the registry: Please see Adverse Events Section
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 | Belimumab SC Q2WKS | Belimumab SC 3X/WK | Total |
|---|---|---|---|---|
| Participants analysed | 28 | 28 | 56 | |
| Age Continuous | years | 39.2 (SD 11.5) | 40.9 (SD 13.1) | 40.1 (SD 12.2) |
| Sex: Female, Male: Female | Participants | 26 | 27 | 53 |
| Sex: Female, Male: Male | Participants | 2 | 1 | 3 |
| Region of Enrollment: United States | participants | 24 | 25 | 49 |
| Region of Enrollment: Mexico | participants | 4 | 3 | 7 |
6. Primary Endpoint
The registry lists the primary outcome as Evaluation of the Number of Participants Who Experienced Adverse Events (AEs) During the 24 Week Period., measured over Up to 24 weeks.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | Percentage of participants |
| Endpoint classification | Binary Endpoint |
The stated primary endpoint concerns the percentage of participants who experienced adverse events during up to 24 weeks. It is a participant-level safety measure: the intended quantity is the proportion of participants with an event during the specified observation period, rather than the total number of events. The registry record also describes the endpoint using the number of participants, so the count and percentage are two ways of expressing the same general type of outcome when a denominator is available.
Adverse-event occurrence is relevant to a study whose stated purpose is to test safety and tolerability of repeated subcutaneous belimumab doses. Comparing the groups can describe whether the observed experience differed across the two schedules. An event count alone does not establish that a drug or schedule caused an event; causal interpretation depends on the design, event definitions, timing, and other evidence.
The primary endpoint description directs readers to the adverse events results section and identifies the population as described there. The posted results include counts for serious and other adverse events by group, but the registry record does not report a distinct overall result for all participants experiencing any adverse event as the primary endpoint. It also does not state the precise event-collection rules or provide an endpoint analysis method. Those details should not be inferred from the endpoint label.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record describes a randomized comparison of two belimumab dosing schedules, with 28 participants at risk for serious adverse events in each group. The serious adverse-event counts were 2 in the every-other-week group and 4 in the three-times-weekly group. The counts for other adverse events were 19 and 18, respectively. These are descriptive counts from the posted results; they do not by themselves establish a difference in risk between schedules.
The record reports no statistical analyses. It does not provide an estimate comparing the groups, a confidence interval, or a test of a between-group difference. Consequently, the precision of any comparison and the range of differences compatible with the data cannot be assessed from the registry results. The counts should not be treated as evidence that one schedule is safer or less safe.
The primary endpoint is the percentage of participants experiencing adverse events during up to 24 weeks, but a distinct overall result for that endpoint is not reported in the registry record. The counts for serious and other adverse events do not necessarily answer that primary question: the record does not specify whether or how those categories map to the overall endpoint, or whether a participant could contribute to more than one category. The record’s pointer to the adverse events results section does not supply an overall endpoint estimate.
The serious-event terms listed include acute myocardial infarction, bradycardia, retroperitoneal haemorrhage, cellulitis, gastroenteritis, and pneumococcal sepsis, each shown with 3.6%. The registry record does not indicate which arm each term belongs to or clarify whether the listed terms represent unique participants. They therefore cannot be used to make an arm-specific comparison.
The study is marked terminated, but the reason and the effect of termination on follow-up are not reported in the registry record. The record also does not say how many participants completed the Week 24 evaluation or entered the continuation period. This missing context limits interpretation of the observation period and completeness of the safety data. The results describe the posted observations; they do not establish a treatment effect or resolve how the schedules compare statistically.
9. Statistical Methods Explained
The available record supports a descriptive reading of the safety counts, but it does not describe a full statistical analysis plan. The study is randomized and parallel-group, while masking is listed as none. Randomization can help balance measured and unmeasured participant characteristics across groups on average, but it does not guarantee balance in a particular study. Open-label conduct also means that knowledge of the assigned schedule was not masked. How that knowledge may have affected event reporting or assessment cannot be determined from the registry record.
What does a participant-level percentage mean?
A participant-level percentage represents the share of an analyzed group who experienced at least one event meeting the endpoint definition during the observation period. It is different from an event rate that counts every episode, because one person can experience more than one event. It is also different from a time-to-event analysis, which uses information about when events occurred and how long participants were observed.
The stated primary outcome is expressed as a percentage of participants and refers to adverse events during up to 24 weeks. However, the registry record does not report the overall endpoint result separately. It reports serious and other adverse-event counts, but does not explain the relationship between those categories and the primary endpoint. Without a definition and a reported overall result, the primary endpoint cannot be reconstructed from the category counts.
Why does the denominator matter?
A count is easiest to interpret alongside the number of people who could have experienced the event. The posted serious-event data give 28 participants at risk in each group, alongside the corresponding event counts. The other-event data also give 28 at risk in each group. These denominators identify the reported groups at risk, but they do not explain how participants with incomplete follow-up were handled or whether the at-risk population differs from the population used for the primary endpoint.
In general, a percentage can be affected by the choice of denominator. An analysis restricted to participants with complete follow-up can differ from one that includes all randomized participants, especially if follow-up is incomplete for reasons related to health or treatment. Which analysis population was used for each reported result, and how missing observations were handled, are not reported in the registry record.
What does a confidence interval add?
In general, a confidence interval expresses uncertainty around an estimated quantity. For a comparison between groups, it can show which effect sizes are reasonably compatible with the observed data under the analysis assumptions. A point estimate alone gives a single summary; an interval communicates that estimates from a study are subject to sampling variability. No confidence interval or comparative estimate is reported in the registry record, so the precision of the group comparison cannot be assessed.
Why can event counts be difficult to compare?
Rare or uncommon events can produce unstable comparisons, particularly when groups are small. A change in a small number of observed participants can materially alter the pattern of counts. More generally, event data can be over-dispersed when participants vary in their underlying risk or when events cluster within individuals. Over-dispersion means the observed variability can be greater than a simple model assumes; methods that ignore it may understate uncertainty. The registry record does not report a model for these data, and the posted counts alone cannot show whether over-dispersion is present.
Serious and other adverse-event categories may also require careful handling. If a participant experiences multiple events, event-level summaries can count more than one event for that person, while participant-level summaries generally count the person once per defined outcome. The registry record does not explain whether the listed categories are mutually exclusive, how repeated events were treated, or whether events were attributed to a particular schedule. Those details matter when moving from a descriptive count to a formal comparison.
What can be inferred from the listed design?
Random allocation provides a basis for comparing the assigned groups, but interpretation still depends on the analysis population, follow-up, outcome definitions, and statistical methods. The registry record does not report the randomization procedure, allocation concealment, prespecified group-comparison method, or handling of protocol deviations. It also reports no statistical analyses. Therefore, the reported event counts should be read as descriptive results, not as estimates that have been adjusted for other factors or tested for statistical significance.
The registry record includes planning assumptions for sample-size illustrations: a two-sided significance level of 0.05, equal allocation, and a normal approximation, with the effect to detect expressed as a fraction of the observed effect. These are described as planning illustrations rather than the trial’s own design justification. The record does not report a sample-size justification for the trial. In general, a planning calculation estimates the sample size associated with specified assumptions; it is not an observed measure of statistical power after the study is complete. No illustration values are reported in the registry record here, and the stated primary outcome is not reduced to a single comparison for that purpose.
10. Multiplicity, Missing Data and Analysis Populations
The registry record names multiple secondary outcomes, including serum belimumab concentration levels over 24 weeks; absolute and median percent changes from baseline in IgA, IgG, and IgM at Week 24; and absolute change from baseline in Physician’s Global Assessment score at Week 24. It reports 32 outcome measures, but no statistical analyses. The analysis methods for these outcomes and any adjustment for multiple comparisons are not reported in the registry record.
In general, testing many outcomes or contrasts creates more opportunities for apparently notable results to arise by chance. Multiplicity methods can control that risk, but the method depends on which outcomes and comparisons were planned and how they were tested. Without a reported analysis plan, it is not possible to determine whether a multiplicity strategy was prespecified or applied. The number of listed measures alone does not reveal how many statistical tests were performed.
Missing-data procedures are also not reported in the registry record. The record does not state how missing outcome measurements, withdrawals, incomplete follow-up, or participants who did not reach Week 24 were handled. It does not identify analysis populations such as all randomized participants or participants with observed measurements. Those omissions matter because a result based on observed measurements can be affected by who remains under observation and why data are missing.
The study is marked terminated, but the reason for termination and its implications for follow-up are not reported. It is therefore not possible to determine from the registry record whether termination affected the planned collection or analysis of outcomes. No assumptions about missingness or multiplicity should be read into the descriptive safety counts.
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 |
|---|---|---|---|
| Belimumab SC Q2WKS | 2 | 28 | 7.1% |
| Belimumab SC 3X/WK | 4 | 28 | 14.3% |
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 |
|---|---|
| Belimumab SC Q2WKS | 19 of 28 |
| Belimumab SC 3X/WK | 18 of 28 |
Most frequent serious adverse event terms
| Event term | Organ system | Belimumab SC Q2WKS | Belimumab SC 3X/WK |
|---|---|---|---|
| Acute myocardial infarction | Cardiac disorders | 1 of 28 | 0 of 28 |
| Bradycardia | Cardiac disorders | 0 of 28 | 1 of 28 |
| Retroperitoneal haemorrhage | Gastrointestinal disorders | 1 of 28 | 0 of 28 |
| Cellulitis | Infections and infestations | 0 of 28 | 1 of 28 |
| Gastroenteritis | Infections and infestations | 0 of 28 | 1 of 28 |
| Pneumococcal sepsis | Infections and infestations | 0 of 28 | 1 of 28 |
| Pyelonephritis | Infections and infestations | 1 of 28 | 0 of 28 |
| Subcutaneous abscess | Infections and infestations | 0 of 28 | 1 of 28 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Belimumab SC Q2WKS | Belimumab SC 3X/WK |
|---|---|---|---|
| Headache | Nervous system disorders | 6 of 28 | 5 of 28 |
| Upper respiratory tract infection | Infections and infestations | 5 of 28 | 3 of 28 |
| Arthralgia | Musculoskeletal and connective tissue disorders | 3 of 28 | 4 of 28 |
| Diarrhoea | Gastrointestinal disorders | 4 of 28 | 1 of 28 |
| Nausea | Gastrointestinal disorders | 2 of 28 | 3 of 28 |
| Fatigue | General disorders | 3 of 28 | 2 of 28 |
| Nasopharyngitis | Infections and infestations | 5 of 28 | 0 of 28 |
| Myalgia | Musculoskeletal and connective tissue disorders | 3 of 28 | 2 of 28 |
| Injection site irritation | General disorders | 2 of 28 | 2 of 28 |
| Arthritis | Musculoskeletal and connective tissue disorders | 1 of 28 | 3 of 28 |
Serious events with the highest arm-level rate: acute myocardial infarction (3.6%), bradycardia (3.6%), retroperitoneal haemorrhage (3.6%), cellulitis (3.6%), gastroenteritis (3.6%).
The serious adverse-event data report 2 affected participants among 28 at risk in the every-other-week group and 4 among 28 at risk in the three-times-weekly group. The other adverse-event counts are 19 among 28 at risk and 18 among 28 at risk, respectively. These are counts, not adjusted comparisons. The registry record does not report confidence intervals or a statistical test for these group differences.
Six serious-event terms are listed with 3.6%: acute myocardial infarction, bradycardia, retroperitoneal haemorrhage, cellulitis, gastroenteritis, and pneumococcal sepsis. The registry record does not report which group each term came from, whether a term occurred in more than one participant, or whether the terms represent all serious events. The listed percentages should therefore not be treated as arm-specific rates or added together.
Deaths are not reported in the registry record. Nor does the record explain the criteria used to classify an event as serious, the timing of events, or the process used to assess relationship to treatment. These omissions limit interpretation of the event listings. An observed adverse event during a trial does not by itself establish that the assigned treatment caused it.
12. What the Result Does, and Does Not, Mean
The posted results describe safety observations in two randomized groups assigned different subcutaneous belimumab schedules. The serious-event counts were 2 and 4 among 28 participants at risk in each group, and the other-event counts were 19 and 18. The registry record also lists serious-event terms, each with a displayed 3.6%, without reporting their group attribution. These findings are descriptive and should be read in that context.
They do not establish that either schedule caused an event, nor do they show that the schedules differ statistically. No comparative effect estimate, confidence interval, or statistical test is reported. Small group counts can be imprecise, and the registry record does not provide enough analysis detail to judge the precision of a comparison. The absence of a reported test is not evidence that the groups are equivalent.
The trial’s stated primary endpoint concerns the percentage of participants experiencing adverse events during up to 24 weeks. The registry record points to the adverse events results section but does not report a distinct overall result for this endpoint. The serious and other event counts should not automatically be taken as a complete substitute, because the record does not define how those categories relate to the overall endpoint.
The registry record does not report results for the listed secondary measures, including pharmacokinetic and immunoglobulin outcomes or the Physician’s Global Assessment measure. It also does not describe the reason for termination, missing-data methods, analysis populations, or the detailed statistical plan. Thus, the available results do not establish the broader biological or clinical effects of the dosing schedules, and they do not settle how the schedules compare. They describe only the safety counts and event terms that are posted.
13. Why This Trial Matters Statistically
This trial is statistically informative as an example of the gap between a stated endpoint and the results that can be interpreted from a registry record. The primary outcome is framed as the percentage of participants experiencing adverse events during up to 24 weeks, while the posted safety information is organized as serious and other event counts. Without a reported overall endpoint result and a clear account of how the categories relate to it, the primary question cannot be answered directly from the listed counts.
The randomized parallel-group design gives a structure for comparing two schedules, but the record reports no statistical analyses. Descriptive counts can show what was recorded in each group; they do not convey the uncertainty around a between-group difference. A comparative estimate and its confidence interval would be needed to assess precision, while analysis details would clarify the population, definitions, and handling of incomplete observations.
The open-label design is also important for interpreting safety reporting. Knowledge of the assigned schedule can be relevant to how symptoms are noticed, reported, or assessed. The record does not describe procedures that might standardize event ascertainment, so the extent of any such influence is unknown. This is not a reason to dismiss the counts; it is a reason to treat them as observations whose interpretation depends on reporting and analysis details.
Finally, the record’s status is terminated, but its reason and consequences for follow-up are not reported. This illustrates why trial status, outcome completeness, and analysis methods matter alongside the numerical results. A registry entry can identify the design and list safety observations while leaving important uncertainties about the planned question and the analysis unresolved.
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 record marks the study terminated but does not report the reason. It also does not state whether termination altered the intended follow-up, outcome collection, or analysis. The schedules were described through the Week 24 evaluation, with an option to continue through a 144 week continuation period, but continuation participation and follow-up completion are not reported.
Details needed to interpret the safety counts are absent. The record does not define the serious and other adverse-event categories, explain whether participants could appear in both, or state whether the counts represent participants with at least one event or another summary rule. The serious-event terms are not assigned to groups, and the record does not say whether listed terms correspond to unique participants. The death counts are not reported.
The population details and analysis populations are not reported. Although enrollment is 56 and each group is listed with 28 at risk for the safety counts, the record does not describe withdrawals, incomplete observation, or the handling of missing data. The method used to randomize participants and the procedures for allocation concealment are not reported. Masking is listed as none.
The registry record also does not report a full statistical analysis plan, a comparative estimate, uncertainty intervals, or statistical tests. The reason for termination, the sample-size justification, and any interim analyses are not reported. The primary endpoint is described, but a distinct overall result for it is not reported. These limitations constrain interpretation to the descriptive safety information that is posted; they do not support assumptions about unreported procedures or results.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Phase 2 Study of Belimumab Administered Subcutaneously to Subjects With Systemic Lupus Erythematosus (SLE) — NCT00732940.
- Registry record last updated 2013-08-07; status last verified 2013-03.
- Results first posted 2011-05-05.
- 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.
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18. Record Summary
NCT00732940 is a phase 2, randomized, open-label, parallel-group study of subcutaneous belimumab in participants with systemic lupus erythematosus. The registry record reports enrollment of 56 and lists two schedules: 100 mg every other week and a schedule beginning with 200 mg three times weekly, followed by 100 mg three times weekly. Both were described through the Week 24 evaluation, with an option to continue for a 144 week period.
The primary outcome concerns the percentage of participants experiencing adverse events during up to 24 weeks. Posted safety counts include serious and other adverse events. The registry record reports no statistical analyses and does not provide a distinct overall result for the primary endpoint, comparative uncertainty estimates, or detailed analysis methods. The study is marked terminated; the reason is not reported in the registry record.