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 BEL114333, a Continuation Study of BEL113750 in Subjects With Systemic Lupus Erythematosus (SLE) in Northeast Asia, and in Japan Subjects Completing the Open-label Extension of HGS1006-C1115 (NCT01597622), a na phase 3 study. The primary outcome is Number of Participants With Adverse Events (AEs) and Serious AEs (SAEs).
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01597622 |
| Phase | Phase 3 |
| Condition | Systemic Lupus Erythematosus |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 142 |
| Arms in the primary outcome | n/a |
| Lead sponsor | GlaxoSmithKline |
| Results posted | Yes |
2. Clinical Question
Population
Participants with systemic lupus erythematosus who completed the BEL113750 study in Northeast Asia or completed the HGS1006-C1115 open-label extension in Japan were eligible to continue into this study. The safety population consisted of enrolled participants who received at least one intravenous dose of belimumab during the current study. The registry record lists 142 participants in the study.
Intervention
Participants received open-label belimumab at 10 mg/kg intravenously every 4 weeks, alongside standard SLE therapies. Participants already randomized to belimumab in a parent study could continue treatment; participants randomized to placebo could begin belimumab. The current study therefore offered ongoing or newly started belimumab, rather than preserving a placebo group.
Comparator
There was no concurrent comparison group in this study. The registry record identifies a single-group model, no masking, and allocation as not applicable. Earlier parent-study assignments explain how participants entered the continuation study, but they do not create a randomized control comparison within this study.
Primary question
The primary outcome counts participants with adverse events and serious adverse events during the stated observation period. It describes the safety experience recorded during extended open-label exposure. The record also lists SLE Responder Index responders by study visit as a secondary outcome, but does not report analysis results for that outcome. Because every participant in the current study received belimumab, the primary counts describe events in this cohort; they cannot by themselves estimate how those outcomes would compare with a group not receiving belimumab.
3. Trial Design
This was a completed Phase III, multicenter continuation study of belimumab in participants with systemic lupus erythematosus. The registry record lists an enrollment of 142. Participants came from the BEL113750 study in Northeast Asia or, in Japan, the HGS1006-C1115 open-label extension. The study offered continuing belimumab to participants who had received it in a parent study and allowed those previously assigned to placebo to begin belimumab.
The current study used a single-group, open-label design. Masking was none, and allocation was not applicable. All participants received belimumab 10 mg/kg intravenously every 4 weeks, with standard SLE therapies during the study. The described treatment continued until belimumab became commercially available in a participant’s country of participation, or until another stopping point; the remainder of that stopping description is not reported in the registry record.
The primary outcome was the number of participants with adverse events and serious adverse events. Its timeframe is listed as up to 6 calendar years and 9 months. The outcome description includes exposure in the parent study and follow-up up to 16 weeks after infusion in the current study. Treatment-emergent events were defined in relation to the first belimumab dose, with additional criteria for ongoing events among participants who had been randomized to placebo in a parent study.
The registry record lists SRI responders by study visit as a secondary outcome. It does not report the protocol’s rationale for the enrollment target, detailed eligibility criteria, interim analyses, or a statistical analysis plan. The single-group structure is central to interpretation: the study can describe observed events in participants receiving belimumab, but does not offer a concurrent untreated or placebo group for estimating a treatment contrast.
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: Total 143 participants were screened for this study and 142 participants were enrolled and received study treatment in current study. BEL113750, a 52 week double-blind study; C1115, a 52 week double-blind study followed by a 6 month open-label extension.
Overall Study
| Stage | Open-label Belimumab 10 mg/kg |
|---|---|
| STARTED | 142 |
| COMPLETED | 104 |
| NOT COMPLETED | 38 |
Reasons for not completing this period:
| Reason | Open-label Belimumab 10 mg/kg |
|---|---|
| Adverse Event | 7 |
| Lack of Efficacy | 3 |
| Protocol Violation | 1 |
| Lost to Follow-up | 1 |
| Investigator Discretion | 5 |
| Withdrawal by Subject | 20 |
| Death | 1 |
Analysis population for the primary outcome, as defined in the registry: Safety Population. All participants in the Enrolled population who received at least one IV dose of belimumab during current study.
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: Baseline is the last available value prior to the first belimumab exposure.
| Characteristic | Unit | Open-label Belimumab 10 mg/kg |
|---|---|---|
| Participants analysed | 142 | |
| Age, Continuous | Years | 34.6 (SD 9.28) |
| Sex: Female, Male: Female | Participants | 129 |
| Sex: Female, Male: Male | Participants | 13 |
| Race/Ethnicity, Customized: American Indian or Alaskan Native | Participants | 1 |
| Race/Ethnicity, Customized: Japanese Heritage | Participants | 71 |
| Race/Ethnicity, Customized: East Asian Heritage | Participants | 68 |
| Race/Ethnicity, Customized: Southeast Asian Heritage | Participants | 2 |
6. Primary Endpoint
The registry lists the primary outcome as Number of Participants With Adverse Events (AEs) and Serious AEs (SAEs), measured over Up to 6 calendar years and 9 months.
| Element | Registry entry |
|---|---|
| Result type | Count Of Participants |
| Measure of spread | not applicable |
| Unit | Participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint counts participants who experienced adverse events and serious adverse events. An adverse event was defined as an untoward medical occurrence temporally associated with use of the medicinal product, whether or not considered related to it. Serious adverse events were those involving death, a life-threatening event, hospitalization or prolonged hospitalization, disability or incapacity, a congenital anomaly or birth defect, or another medically important event.
Counting participants is useful for describing how many people in the safety population experienced at least one event. It avoids treating repeated events in the same person as if they were separate participants. The endpoint description states that the count for any adverse event includes participants with non-serious and/or serious events. The serious adverse event count is a separate safety summary; it is not a count of all individual serious-event episodes.
Safety endpoints are used to characterize events observed during treatment and follow-up. They do not, by themselves, establish that treatment caused an event. The definition explicitly includes events whether or not considered related to the medicinal product. Since this study had no concurrent comparison group, the counts also cannot establish how often such events would have occurred under another treatment or without belimumab. The registry record does not report a formal causal assessment or an inferential comparison for this endpoint.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The posted safety results describe one open-label belimumab group. Among the 142 participants at risk for the listed adverse event summaries, 48 had at least one serious adverse event, 134 had at least one adverse event of any seriousness, and 1 death is listed. These are participant counts, not numbers of event episodes. A participant may have experienced more than one event, and the any-adverse-event category includes participants with serious and/or non-serious events.
The record lists several of the most frequent serious adverse event terms with percentages: cellulitis, herpes zoster, and contusion at 2.1% each; endocarditis, acute pyelonephritis, and pyrexia at 1.4% each. These are presented as serious-event terms, not as evidence that belimumab caused the events. The endpoint definition includes events regardless of whether they were considered related to the medicinal product. The registry record does not report participant-level event histories or a causal assessment for each term.
Observation covered a long period: the primary outcome timeframe is up to 6 calendar years and 9 months, and the endpoint description includes parent-study exposure and up to 16 weeks after infusion in the current study. Long follow-up can capture events occurring over extended treatment exposure, but it also means that participants may not all have had identical observation time. The registry record does not report individual follow-up durations or an exposure-adjusted event analysis. The raw participant counts therefore should not be read as event rates per unit of time.
There is no concurrent control group and no random allocation within this continuation study. The observed counts can describe what was recorded among participants receiving belimumab, but they cannot distinguish treatment effects from the underlying disease, background therapies, prior study exposure, or other influences. The registry record reports no inferential analyses for the listed outcomes. No p-values or confidence intervals for these safety counts are reported in the registry record.
The record also lists SRI responders by study visit as a secondary outcome, but does not include the corresponding results or an analysis. The safety findings should therefore be kept distinct from any claim about clinical response. Overall, the figures provide descriptive safety information for this cohort and observation period. They do not establish comparative safety, quantify risk relative to another treatment, or demonstrate a causal relationship between belimumab and any listed event.
9. Statistical Methods Explained
The registry record describes a single-group, open-label study and reports participant counts for safety outcomes. That design determines what statistical conclusions are available. In a randomized comparison, treatment groups can be contrasted to estimate differences under the study’s assumptions. Here, all participants in the current study received belimumab, so the posted counts describe the observed cohort rather than a treatment contrast.
What participant counts represent
A count of participants with an event records whether each person experienced at least one qualifying event during the defined observation period. It does not count every recurrence. For the any-adverse-event outcome, the endpoint description includes participants who had non-serious events, serious events, or both. The serious adverse event count answers a narrower question about participants meeting the serious-event definition. These two summaries can overlap because a serious event is also an adverse event, but they are not interchangeable measures.
General statistical context: a participant proportion is often presented alongside a count to make a result easier to compare across groups of different sizes. That comparison is most useful when the populations, event definitions, and follow-up periods are sufficiently similar. A proportion still does not account for differences in time under observation. For an extended study, person-time methods can sometimes describe event occurrence relative to the amount of follow-up, but the registry record does not report such an analysis for these results.
What a confidence interval would add
General statistical context: a confidence interval expresses uncertainty around an estimated quantity, such as a participant proportion or a difference between groups. It reflects sampling variability under the method used; it does not remove bias, establish causation, or account automatically for every feature of the study design. For a single-group safety proportion, an interval could describe uncertainty about the underlying proportion represented by the observed cohort, but it would not provide a comparison with a control group. Confidence intervals for these outcomes are not reported in the registry record.
Why comparisons require caution
General statistical context: random allocation is intended to make treatment groups comparable, on average, with respect to measured and unmeasured factors at the start of a trial. That benefit applies to a randomized comparison within the relevant study. In a continuation study, earlier assignment in a parent study does not substitute for a concurrent randomized control if everyone in the current study receives the same treatment. Participants may also enter from different parent-study pathways. The registry record identifies those pathways but does not report a comparative analysis by prior assignment or source study.
Open-label treatment means that masking was not used. General statistical context: knowledge of treatment can influence reporting, assessment, decisions about follow-up, or attribution of events, although the extent depends on the outcome and study procedures. The endpoint definition includes events regardless of whether they were considered related to the medicinal product, which is relevant when interpreting the event counts. Details about adjudication or blinded event review are not reported in the registry record.
Repeated events and timing
Participant counts answer whether people experienced one or more events, not how many events occurred, how often they recurred, or when they began. The listed serious-event terms and percentages are not a complete participant-level account of event timing. The outcome timeframe extends up to 6 calendar years and 9 months and includes exposure in a parent study as well as follow-up up to 16 weeks after infusion in the current study. The registry record does not report a time-to-event analysis, an exposure-adjusted event rate, or a detailed distribution of follow-up duration.
General statistical context: when observation time varies, time-to-event analyses can incorporate the timing of an event and account for participants whose observation ends before an event is observed. Such methods require defined event times and follow-up information, as well as assumptions appropriate to the analysis. Those details and analyses are not reported in the registry record. It is therefore appropriate to read the posted values as descriptive participant counts rather than as estimates of event incidence over a common amount of time.
Over-dispersion and count models
General statistical context: over-dispersion occurs when count data vary more than a model’s assumptions allow. It matters when modeling numbers of events, because underestimated variability can make uncertainty appear too small. The primary results are counts of participants with events, not a modeled count of recurrent event episodes. The registry record does not report a count model, an assessment of over-dispersion, or a recurrent-event analysis, so no such method should be inferred.
Analysis results and planning
The registry record lists zero analyses. It does not report p-values, confidence intervals, adjusted estimates, or results for the listed SRI responder outcome. A sample-size justification, interim analysis plan, and detailed statistical analysis plan are not reported in the registry record. General statistical context: planning illustrations based on an observed effect are not observed power and do not replace a trial’s design rationale or its analysis. No inferential result should be inferred from the descriptive safety counts alone.
10. Multiplicity, Missing Data and Analysis Populations
The registry record lists a primary safety outcome and a secondary outcome of SRI responders by study visit. It does not report the multiplicity strategy, such as whether any adjustment was planned for testing more than one outcome or multiple study visits. Since no analysis results are reported for the secondary SRI outcome, the record does not allow assessment of how those repeated visit-specific results were handled.
Missing-data methods are not reported in the registry record. The safety population is defined as enrolled participants who received at least one intravenous dose of belimumab during the current study. The record does not describe how participants with incomplete follow-up, treatment discontinuation, or missing outcome information contributed to the summaries. It also does not report imputation methods or sensitivity analyses for missing observations.
The analysis populations are only partly described. The primary outcome specifies a safety population, and the overall study enrollment is listed as 142. The adverse event summaries list 142 participants at risk. A separate population definition for the secondary SRI outcome, or a distinction between intention-to-treat and other analysis sets, is not reported in the registry record.
General statistical context: multiplicity can increase the chance of at least one false-positive finding when several hypotheses are tested. Missing-data methods can affect estimates when outcome availability is related to participants’ health, treatment, or follow-up. These concerns cannot be evaluated from the listed counts alone. The registry record does not report a protocol-level statistical plan, interim analyses, or the handling of missing data and multiplicity.
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 |
|---|---|---|---|
| Open-label Belimumab 10 mg/kg | 48 | 142 | 33.8% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Open-label Belimumab 10 mg/kg | 1 of 142 |
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 |
|---|---|
| Open-label Belimumab 10 mg/kg | 134 of 142 |
Most frequent serious adverse event terms
| Event term | Organ system | Open-label Belimumab 10 mg/kg |
|---|---|---|
| Cellulitis | Infections and infestations | 3 of 142 |
| Herpes zoster | Infections and infestations | 3 of 142 |
| Contusion | Injury, poisoning and procedural complications | 3 of 142 |
| Endocarditis | Infections and infestations | 2 of 142 |
| Pyelonephritis acute | Infections and infestations | 2 of 142 |
| Pyrexia | General disorders | 2 of 142 |
| Uterine leiomyoma | Neoplasms benign, malignant and unspecified (incl cysts and polyps) | 2 of 142 |
| Osteonecrosis | Musculoskeletal and connective tissue disorders | 2 of 142 |
| Abscess jaw | Infections and infestations | 1 of 142 |
| Atypical pneumonia | Infections and infestations | 1 of 142 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Open-label Belimumab 10 mg/kg |
|---|---|---|
| Nasopharyngitis | Infections and infestations | 86 of 142 |
| Headache | Nervous system disorders | 40 of 142 |
| Cough | Respiratory, thoracic and mediastinal disorders | 26 of 142 |
| Viral upper respiratory tract infection | Infections and infestations | 25 of 142 |
| Herpes zoster | Infections and infestations | 23 of 142 |
| Abdominal pain upper | Gastrointestinal disorders | 23 of 142 |
| Nausea | Gastrointestinal disorders | 23 of 142 |
| Upper respiratory tract infection | Infections and infestations | 22 of 142 |
| Diarrhoea | Gastrointestinal disorders | 22 of 142 |
| Influenza | Infections and infestations | 20 of 142 |
Serious events with the highest arm-level rate: cellulitis (2.1%), herpes zoster (2.1%), contusion (2.1%), endocarditis (1.4%), pyelonephritis acute (1.4%).
The safety group is listed as open-label belimumab 10 mg/kg, with 142 participants at risk for both the serious and any-adverse-event summaries. The registry record reports 48 participants with at least one serious adverse event and 134 participants with at least one adverse event of any seriousness. It also lists 1 death. These are counts of participants, not counts of all event episodes. Participants with serious events may also be included among those with any adverse event.
The serious adverse event terms listed include cellulitis, herpes zoster, and contusion at 2.1% each, and endocarditis, acute pyelonephritis, and pyrexia at 1.4% each. The percentages are reproduced as recorded; they should be understood as summaries of the listed terms, not as causal estimates. The endpoint definition includes events whether or not they were considered related to the medicinal product.
The observation period was up to 6 calendar years and 9 months, with the endpoint description including parent-study exposure and up to 16 weeks after infusion in the current study. The registry record does not report an exposure-adjusted event rate, a comparison group, or a detailed account of follow-up time for individual participants. These summaries therefore describe recorded events in the study cohort; they do not establish the event frequency that would have occurred under another treatment.
12. What the Result Does, and Does Not, Mean
The principal meaning of the posted results is descriptive. They record how many participants in the open-label belimumab group experienced adverse events and serious adverse events over the defined observation period. The listed counts and serious-event terms provide information about the cohort’s observed safety experience, but they do not establish that belimumab caused any particular event.
The study was a continuation study with one treatment group. Participants who had received belimumab in a parent study could continue it, while participants previously randomized to placebo could begin it. Once in the current study, all participants received belimumab. Consequently, there is no within-study control group against which to estimate a difference in adverse event experience. Differences from other studies or populations cannot be interpreted as treatment effects without appropriate comparable data and analysis.
The count of participants with an event also does not reveal the total number of event episodes, their timing, duration, severity beyond the recorded categories, or the amount of follow-up for each person. The long observation window makes this distinction important: participant counts alone do not adjust for varying time exposed or observed. The registry record does not report an exposure-adjusted analysis or individual event histories.
The record lists SRI responders by study visit as a secondary outcome, but does not report its results or statistical analysis. Thus, the adverse event findings should not be taken as evidence for or against clinical response. Nor do the figures provide a comparison of benefits and harms. They support a description of reported events in this cohort; comparative effectiveness, comparative safety, and causal conclusions are not established by these data.
General statistical context: a descriptive study can still document outcomes in a defined group and help characterize what occurred during follow-up. Its conclusions depend on the population enrolled, outcome definitions, completeness of observation, and design. Here, the continuation setting and absence of a concurrent control constrain interpretation. The results are best read as cohort-specific safety observations rather than as a controlled estimate of treatment effect.
13. Why This Trial Matters Statistically
This study is statistically informative because it illustrates the distinction between describing an outcome and estimating a comparative treatment effect. Its single-group design records adverse events during open-label belimumab treatment, but does not contain a concurrent group receiving a different treatment. That design can answer what was observed among participants in the cohort; it cannot by itself answer how the same participants would have fared under an alternative treatment.
The continuation setting also shapes the population represented. Participants entered after completing different parent-study pathways in Northeast Asia or Japan. Some continued belimumab, while others began belimumab after earlier placebo assignment. Their shared treatment in the continuation study does not erase those different histories, and the registry record does not report an analysis separating outcomes by prior assignment or parent study.
The safety endpoint demonstrates why the unit of analysis matters. The results count participants with one or more events rather than every event episode. That is a useful way to summarize how many people were affected, but it does not describe recurrence, timing, or event rates per time exposed. With an observation window extending up to 6 calendar years and 9 months, duration of follow-up is part of the context needed to interpret counts.
Finally, the record lists a secondary SRI responder outcome without reporting its results, and lists no analyses. This makes clear that outcome names alone do not establish an efficacy finding. Statistical interpretation depends on reported estimates, uncertainty, analysis populations, and methods, as well as study design. The posted information supports a focused descriptive account of safety, while leaving comparative and inferential questions unanswered.
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 most important design limitation is the absence of a concurrent control group. The study is single-group and open-label, so event counts cannot be contrasted with outcomes under placebo or another treatment within this study. The lack of masking may also affect event reporting or assessment; details about blinded review or adjudication are not reported in the registry record.
The cohort consists of participants who completed a parent study or a specified open-label extension, rather than a general sample of people with SLE. Entry pathways included participants from BEL113750 in Northeast Asia and participants from the HGS1006-C1115 extension in Japan. The registry record does not report comparative outcome analyses by parent study or previous treatment assignment. Results may therefore reflect characteristics and treatment histories specific to this continuation cohort.
The primary outcome summarizes participants with at least one event, not event episodes or events per unit of exposure. The timeframe is up to 6 calendar years and 9 months, and includes parent-study exposure and follow-up up to 16 weeks after infusion in the current study. Individual follow-up durations, event timing, exposure-adjusted rates, and recurrent-event analyses are not reported in the registry record.
The registry record lists zero analyses and does not report confidence intervals, p-values, a detailed statistical analysis plan, a sample-size justification, missing-data methods, or a multiplicity strategy. The SRI responder outcome is listed without analysis results. These omissions limit assessment of statistical uncertainty, incomplete follow-up, and any outcome beyond the reported safety counts. The descriptive findings should not be extended to causal or comparative claims.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: BEL114333, a Continuation Study of BEL113750 in Subjects With Systemic Lupus Erythematosus (SLE) in Northeast Asia, and in Japan Subjects Completing the Open-label Extension of HGS1006-C1115 — NCT01597622.
- Registry record last updated 2020-03-27; status last verified 2020-03.
- Results first posted 2020-01-09.
- 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
NCT01597622 is a completed Phase III continuation study of belimumab in participants with systemic lupus erythematosus. It enrolled 142 participants from the BEL113750 study in Northeast Asia or the HGS1006-C1115 open-label extension in Japan. The current study was single-group and open-label, with belimumab 10 mg/kg administered intravenously every 4 weeks alongside standard SLE therapies.
The primary outcome counted participants with adverse events and serious adverse events. The listed safety summaries include 48 participants with a serious adverse event, 134 with an adverse event of any seriousness, and 1 death. The registry record also lists SRI responders by study visit as a secondary outcome, but does not report its results or any analyses. The design supports descriptive safety interpretation, not a controlled comparison or a causal estimate.