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 Clazakizumab for the Treatment of Chronic Active Antibody Mediated Rejection in Kidney Transplant Recipients (NCT03744910), a randomized phase 3 study. The primary outcome is Change From Baseline to Week 52 in Estimated Glomerular Filtration Rate (eGFR).
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT03744910 |
| Phase | Phase 3 |
| Condition | Antibody-mediated Rejection |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Quadruple |
| Enrollment | 194 |
| Arms in the primary outcome | 2 |
| Lead sponsor | CSL Behring |
| Results posted | Yes |
2. Clinical Question
Population
Kidney transplant recipients with antibody-mediated rejection; the trial summary describes the condition as chronic active antibody-mediated rejection. The primary analysis population was defined as randomized participants who received at least 1 dose of study drug and had a baseline and at least 1 post-baseline eGFR assessment.
Intervention
Clazakizumab, a humanized monoclonal antibody that binds human IL-6 and is administered subcutaneously.
Comparator
Placebo, described as physiologic saline solution administered subcutaneously.
Primary question
What was the difference between clazakizumab and placebo in change from baseline to week 52 in estimated glomerular filtration rate (eGFR), as measured in milliliters per minute per 1.73 meter^2?
The clinical question is framed around a continuous measure of kidney function rather than a single event. The posted arm estimates describe average change in eGFR, and the reported treatment difference compares the groups on that outcome. The registry record identifies the primary result as coming from the first interim analysis. It does not report the broader interim-analysis plan, so the timing and role of other possible analyses cannot be established from the record.
The trial also lists outcomes related to allograft loss, irreversible loss of allograft function, urine albumin creatinine ratio, and donor-specific antibodies. These address other aspects of graft status and immune activity, but they are not substitutes for the stated primary question. The record describes the study as investigating efficacy and safety; the posted primary result addresses only the specified eGFR change over the stated timeframe.
3. Trial Design
This was a phase 3 randomized, quadruple-masked, parallel-group trial sponsored by CSL Behring. The registry lists enrollment of 194 and two interventions: subcutaneous clazakizumab and subcutaneous physiologic saline solution as placebo. Random allocation is intended to make the groups comparable at the start of a trial on average, while masking is intended to limit the influence of treatment knowledge on participant care, outcome assessment, and related trial processes. The registry does not identify the four masked roles, so their identities should not be inferred.
The study began on 2019-10-14, and the listed primary completion date is 2024-04-08. Its status is terminated. The reason for termination, the date of termination, and whether termination affected follow-up or the planned analyses are not reported in the registry record. The enrollment figure is the registered trial enrollment; it should not be treated as the analysis count for every outcome.
For the primary outcome, the registry reports 92 participants in the clazakizumab arm and 99 in the placebo arm. The analysis population is described as the intent-to-treat (ITT) analysis set, but its operational definition is narrower than simply all randomized participants: participants had to receive at least 1 dose and have baseline and post-baseline eGFR assessments. The record does not explain how participants lacking those assessments were handled.
The primary endpoint is change from baseline to week 52 in eGFR, reported as a least-squares mean with a 95% confidence interval. The description states that this primary outcome measure was the one from the first interim analysis. The trial protocol, detailed statistical analysis plan, allocation ratio, and sample-size justification are not reported in the registry record.
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: A total of 382 participants were screened, of which 188 were screen failures. Of the screened participants, 194 were randomized in a 1:1 ratio to receive study interventions (Clazakizumab or Placebo).
Overall Study
| Stage | Clazakizumab | Placebo |
|---|---|---|
| STARTED | 94 | 100 |
| COMPLETED | 16 | 15 |
| NOT COMPLETED | 78 | 85 |
Reasons for not completing this period:
| Reason | Clazakizumab | Placebo |
|---|---|---|
| Withdrew Consent | 1 | 8 |
| Physician Decision | 5 | 4 |
| Sponsor Decision (due to study termination) | 68 | 71 |
| Lost to Follow-up | 0 | 1 |
| Other-unspecified | 4 | 1 |
Analysis population for the primary outcome, as defined in the registry: Analysis was performed on the intent-to-treat (ITT) analysis set. The ITT analysis set consisted of all randomized participants who received at least 1 dose of study drug and who had a baseline assessment and at least 1 post baseline assessment of eGFR.
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: Analysis was performed on randomized set, which included all participants who were randomized.
| Characteristic | Unit | Clazakizumab | Placebo | Total |
|---|---|---|---|---|
| Participants analysed | 94 | 100 | 194 | |
| Age, Continuous | years | 46.3 (SD 11.87) | 47.0 (SD 12.24) | 46.7 (SD 12.04) |
| Sex: Female, Male: Female | Participants | 29 | 26 | 55 |
| Sex: Female, Male: Male | Participants | 65 | 74 | 139 |
| Race/Ethnicity, Customized: Ethnicity – Not Hispanic, Latino/a or of Spanish origin | Participants | 69 | 78 | 147 |
| Race/Ethnicity, Customized: Ethnicity – Hispanic, Latino/a or of Spanish origin | Participants | 18 | 16 | 34 |
| Race/Ethnicity, Customized: Ethnicity – Not reported | Participants | 5 | 4 | 9 |
| Race/Ethnicity, Customized: Ethnicity – Unknown | Participants | 2 | 2 | 4 |
| Race/Ethnicity, Customized: Race – White | Participants | 62 | 69 | 131 |
| Race/Ethnicity, Customized: Race – Black or African American | Participants | 10 | 7 | 17 |
| Race/Ethnicity, Customized: Race – Korean | Participants | 9 | 13 | 22 |
| Race/Ethnicity, Customized: Race – Other | Participants | 6 | 8 | 14 |
| Race/Ethnicity, Customized: Race – Asian Indian | Participants | 3 | 1 | 4 |
| Race/Ethnicity, Customized: Race – Other Asian | Participants | 2 | 1 | 3 |
| Race/Ethnicity, Customized: Race – American or Alaskan Native | Participants | 1 | 0 | 1 |
| Race/Ethnicity, Customized: Race – Filipino | Participants | 1 | 0 | 1 |
6. Primary Endpoint
The registry lists the primary outcome as Change From Baseline to Week 52 in Estimated Glomerular Filtration Rate (eGFR), measured over From Baseline to Week 52.
| Element | Registry entry |
|---|---|
| Result type | Least Squares Mean |
| Measure of spread | 95% Confidence Interval |
| Unit | milliliter per minute per 1.73 meter^2 |
| Endpoint classification | Continuous Endpoint |
Estimated glomerular filtration rate (eGFR) is a continuous measure used to assess kidney function. The primary endpoint records the change from each participant’s baseline eGFR to the week 52 assessment, in milliliters per minute per 1.73 meter^2. A negative change represents a decline from baseline. The registry reports least-squares mean changes for each arm, which are model-based estimates of the group mean rather than simple summaries identified as raw averages.
Comparing change over time can help distinguish the groups’ average trajectories while accounting for baseline measurements and other terms in an analysis model. However, the registry record does not specify the model terms or the details of the estimation procedure. It also does not describe how measurements at week 52 were handled when unavailable.
The reported arm estimates are -8.0 for clazakizumab and -5.2 for placebo. The reported treatment difference is -2.75, with a 95% confidence interval from -5.84 to 0.35. These numbers describe the posted analysis of eGFR change; they do not by themselves establish why a change occurred or how it relates to other clinical outcomes. The registry record labels the result as coming from the first interim analysis, which is relevant context when interpreting a primary endpoint result.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
In the primary analysis, the least-squares mean change in eGFR from baseline to week 52 was -8.0 in the clazakizumab group and -5.2 in the placebo group. The reported treatment difference was -2.75, with a 95% confidence interval from -5.84 to 0.35. The interval includes zero, so the posted estimate is not precise enough to rule out no difference between groups at the level represented by that interval. It also spans values on either side of zero, leaving uncertainty about the direction of the underlying difference.
The point estimate is negative, and the arm estimates show a larger decline in the clazakizumab group than in the placebo group. This is a description of the observed analysis, not a conclusion that the treatment caused the difference. The interval is compatible with a difference in the negative direction as well as with a modest difference in the positive direction. The registry does not report a p-value for this comparison, so an exact significance test result should not be inferred from the confidence interval alone.
A confidence interval describes the uncertainty around an estimated effect under the analysis used. It is not a range containing a fixed proportion of individual participants’ changes, and it does not account automatically for uncertainties that are not represented in the analysis, such as unreported missing-data assumptions or choices made in the statistical model. The registry supplies the interval but not the full analysis specification needed to assess those issues.
The secondary outcomes add context but do not resolve the uncertainty in the primary eGFR result. For the binary allograft outcomes with arm counts and recalculated comparisons posted, the event counts and unadjusted risk estimates are numerically higher in the clazakizumab arm. The confidence intervals for those risk differences include zero. These analyses are secondary and unadjusted; the registry record does not report a multiplicity strategy that would support treating their nominal comparisons as confirmatory evidence.
The result should also be read in light of trial status. The registry lists the study as terminated, but does not report the reason or explain how the termination relates to the primary analysis. The record identifies the primary result as one from the first interim analysis, but does not report the interim-analysis plan or the extent of follow-up represented by that result. The posted numbers therefore describe the recorded analysis and its statistical uncertainty; they do not answer questions that depend on unreported design or follow-up details.
9. Statistical Methods Explained
The primary result is presented as a least-squares mean change for each arm and a treatment difference with a 95% confidence interval. The endpoint is continuous, meaning that eGFR change can take a range of values rather than only event/no-event values. An arm-level mean summarizes the center of the group’s outcome distribution. A difference between group means summarizes the estimated contrast, while the confidence interval conveys the precision of that contrast under the analysis used.
What does the confidence interval say?
In general, a confidence interval is a range of values reasonably compatible with the observed data and the statistical procedure used to construct it. A narrower interval indicates greater precision than a wider interval, assuming comparable methods and settings. The primary interval extends from -5.84 to 0.35 and includes zero. In general, when an interval for a difference includes zero, the data do not exclude no difference at the confidence level used. That does not prove the groups are identical; it means the estimate remains uncertain over a range that includes no difference.
The confidence interval is not a guarantee that the true effect lies within the displayed limits, nor does it describe the spread of individual participant outcomes. It quantifies sampling uncertainty under the analysis assumptions. It does not, by itself, capture uncertainty from unreported model choices, missing-data handling, deviations from the planned design, or the trial’s termination.
How should the arm estimates be read?
The reported changes are -8.0 for clazakizumab and -5.2 for placebo. These are least-squares means, not identified as unadjusted sample averages. The treatment difference is separately reported as -2.75. The registry record does not identify the statistical model or list its covariates, so the exact adjustment behind the least-squares means cannot be reconstructed from the posted information. The treatment difference and its interval should therefore be read as the sponsor-reported comparison rather than as a result that can be reproduced from arm summaries alone.
The record does not report a p-value for the primary contrast. A p-value is a measure of how unusual results at least as incompatible with a null hypothesis would be under a specified statistical model if that null hypothesis were true. It is not the probability that the null hypothesis is true, and it does not measure the size or clinical importance of an effect. No value should be inferred where the registry does not report one.
Why do binary comparisons need separate interpretation?
Binary outcomes record whether an event occurred. A risk difference expresses the difference between the event proportions in two groups. The recalculated binary comparisons are explicitly unadjusted, so they use the posted event counts and group sizes without adjustment for other variables. Their confidence intervals describe uncertainty in those unadjusted contrasts. They should not be read as equivalent to a sponsor’s prespecified adjusted analysis, and the registry record does not report sponsor analyses for these secondary comparisons.
The registry also includes relative measures for some binary outcomes, but the risk difference offers an absolute contrast in event frequency. All these measures are affected by the small number of observed events and the uncertainty associated with estimates from finite groups. A confidence interval spanning no difference signals that the data do not clearly distinguish a difference from no difference under that calculation. The values are exploratory recalculations rather than reported sponsor tests.
What do the planning illustrations mean?
For selected binary outcomes, the planning illustrations show participants per arm for 80% power and participants per arm for 90% power under stated assumptions. The assumptions are a two-sided significance level of 0.05, equal allocation between arms, and a normal approximation; the effect to detect is a stated fraction of the observed effect. These are planning illustrations based on observed effects, not the trial’s own sample-size justification and not observed power. The registry record does not report the trial’s original sample-size assumptions or justification.
Such illustrations are sensitive to the effect size chosen for planning. Using a fraction of an observed effect illustrates how a smaller target effect would require a different enrollment under the same assumptions; it does not establish that the observed effect is a stable estimate of what a future trial should expect. In general, over-dispersion—greater variability than assumed by a model—can make standard errors too small and confidence intervals too narrow if it is not accounted for. The registry record does not report an over-dispersion assessment, so no conclusion about its presence or handling can be drawn.
For time-to-event outcomes, planning methods can be based on event counts rather than participants; the stated planning assumptions distinguish those outcomes from other measures. That distinction is general statistical context and does not establish that the primary continuous eGFR endpoint was planned using those event-based methods.
What cannot be established from the registry record?
The record does not report the full statistical analysis plan, the primary model specification, the method used to handle missing outcome data, or sensitivity analyses. It does not state whether any secondary-outcome multiplicity correction was planned or used. The primary result is identified as coming from the first interim analysis, but the details of interim monitoring and any decision rules are not reported. These omissions limit the ability to assess whether the posted results match all planned analyses or how robust the estimates are to alternative assumptions.
10. Analyses Reported by the Sponsor
| Method | Estimate | 95% CI | P-value |
|---|---|---|---|
| not stated | Treatment difference -2.75 | -5.84 to 0.35 | not reported |
The registry reports the primary treatment difference as -2.75, with a 95% confidence interval from -5.84 to 0.35. This is the sponsor-reported analysis in the posted record. A recalculated comparison is not available for this continuous endpoint because the posted summary statistics are insufficient to reproduce an unadjusted two-arm comparison. The arm-level least-squares means and their confidence intervals do not provide the residual variability or other analysis details needed to reconstruct that calculation.
The sponsor-reported estimate therefore takes precedence over a summary-statistic recalculation for the primary endpoint; no independent recalculation is displayed for this outcome. The registry does not identify the model used for the sponsor’s treatment difference, so the estimate cannot be independently checked against a complete model specification using the record alone. The p-value is not reported in the registry record.
For selected secondary binary outcomes, the posted event counts permit simple unadjusted recalculations. Those are distinct from sponsor analyses, and the registry does not list sponsor-reported comparative analyses for those outcomes. Their values should not be presented as if they were the trial’s prespecified inferential results. The primary estimate and its confidence interval remain the central reported comparison for the stated primary endpoint.
11. Multiplicity, Missing Data and Analysis Populations
The registry describes the primary analysis population as the ITT analysis set, defined as randomized participants who received at least 1 dose of study drug and had a baseline assessment and at least 1 post-baseline eGFR assessment. This definition is important: it does not include every randomized participant regardless of treatment exposure or availability of an eGFR assessment. The record does not explain the number or characteristics of randomized participants who did not meet this definition, or how their outcomes were handled.
Missing-data methods are not reported in the registry record. It is therefore not possible to establish whether the analysis used imputation, a likelihood-based approach, another method, or no formal adjustment for missing measurements. The record also does not report sensitivity analyses assessing whether the primary result changes under different assumptions about missing data. Because the study is listed as terminated, information about the reason for termination and its effect on outcome follow-up would be relevant, but those details are not reported.
The primary outcome description says the measure was from the first interim analysis. The registry does not report how many interim analyses were planned, whether any statistical monitoring or stopping boundaries were used, or whether the reported analysis was adjusted for repeated looks at the data. It would be inappropriate to infer these features from the phrase “first interim analysis” alone.
The trial includes numerous outcome measures and secondary comparisons. In general, testing many outcomes can increase the chance of false-positive findings unless the analysis plan accounts for multiplicity through a prespecified hierarchy, adjustment, or other strategy. The registry record does not report whether such a strategy was planned or applied to the secondary outcomes. The unadjusted secondary recalculations should consequently be interpreted with caution and should not be treated as confirmatory findings.
The registry does not report the primary model’s full specification, its assumptions, or a detailed protocol-based analysis plan. These omissions limit assessment of analysis-population choices, missing-data sensitivity, interim monitoring, and multiplicity. They do not invalidate the posted numerical estimates, but they constrain the conclusions that can be drawn from them.
12. 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 |
|---|---|---|---|
| Clazakizumab | 39 | 93 | 41.9% |
| Placebo | 39 | 100 | 39.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Clazakizumab | 3 of 93 |
| Placebo | 1 of 100 |
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 |
|---|---|
| Clazakizumab | 81 of 93 |
| Placebo | 80 of 100 |
Most frequent serious adverse event terms
| Event term | Organ system | Clazakizumab | Placebo |
|---|---|---|---|
| COVID-19 | Infections and infestations | 13 of 93 | 10 of 100 |
| Acute kidney injury | Renal and urinary disorders | 13 of 93 | 6 of 100 |
| Diarrhoea | Gastrointestinal disorders | 4 of 93 | 3 of 100 |
| Anaemia | Blood and lymphatic system disorders | 3 of 93 | 2 of 100 |
| Pneumonia | Infections and infestations | 3 of 93 | 1 of 100 |
| COVID-19 pneumonia | Infections and infestations | 2 of 93 | 1 of 100 |
| Gastroenteritis | Infections and infestations | 1 of 93 | 2 of 100 |
| Renal impairment | Renal and urinary disorders | 2 of 93 | 1 of 100 |
| Transplant rejection | Immune system disorders | 1 of 93 | 2 of 100 |
| Clostridium difficile infection | Infections and infestations | 2 of 93 | 0 of 100 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Clazakizumab | Placebo |
|---|---|---|---|
| COVID-19 | Infections and infestations | 28 of 93 | 30 of 100 |
| Diarrhoea | Gastrointestinal disorders | 21 of 93 | 22 of 100 |
| Oedema peripheral | General disorders | 24 of 93 | 11 of 100 |
| Anaemia | Blood and lymphatic system disorders | 16 of 93 | 16 of 100 |
| Hyperkalaemia | Metabolism and nutrition disorders | 12 of 93 | 13 of 100 |
| Hypertension | Vascular disorders | 12 of 93 | 13 of 100 |
| Blood creatinine increased | Investigations | 9 of 93 | 13 of 100 |
| Headache | Nervous system disorders | 10 of 93 | 9 of 100 |
| Urinary tract infection | Infections and infestations | 12 of 93 | 6 of 100 |
| Nausea | Gastrointestinal disorders | 11 of 93 | 6 of 100 |
Serious events with the highest arm-level rate: covid-19 (14.0%), acute kidney injury (14.0%), diarrhoea (4.3%), pneumonia (3.2%), anaemia (3.2%).
The safety figures are participant counts among those at risk in each arm. Serious adverse events affected 39 of 93 participants at risk in the clazakizumab group and 39 of 100 at risk in the placebo group. Other adverse events affected 81 of 93 and 80 of 100 participants, respectively. The registry also records 3 deaths in the clazakizumab group and 1 in the placebo group. These are descriptive counts; the record does not establish that deaths or events were caused by study treatment.
The listed serious adverse event terms include COVID-19 and acute kidney injury, each reported as 14.0%, followed by diarrhoea at 4.3%, pneumonia and anaemia at 3.2% each, and COVID-19 pneumonia at 2.2%. The record does not identify these term percentages by treatment arm in the information available, so they should not be assigned to a particular group. Nor do the counts alone describe event severity beyond the serious-event classification, timing, duration, or recurrence.
Safety comparisons require attention to who was counted, the observation period, event definitions, and whether participants could experience more than one event. Those details are not reported. The figures should be read as recorded safety summaries, not as a causal comparison or a basis for medical advice.
13. What the Result Does, and Does Not, Mean
The primary result describes a difference in average eGFR change between randomized groups over the stated period. The estimated changes were negative in both groups, and the reported contrast was -2.75 with a 95% confidence interval from -5.84 to 0.35. Because the interval includes zero, the data do not establish a clear difference between groups in this analysis. The interval also leaves uncertainty about the direction and magnitude of the underlying contrast.
This result does not show that the groups were equivalent. Establishing equivalence or non-inferiority requires a specified margin and an analysis designed for that question; neither is reported in the registry record. Likewise, the result does not prove that clazakizumab caused a larger decline, that placebo caused a smaller decline, or that either group’s change has a particular clinical consequence. The trial comparison and its uncertainty are the evidence available in the posted primary analysis.
The result also does not answer every question about kidney transplant outcomes. eGFR change is one continuous measure, while graft loss, irreversible loss of function, albuminuria, and donor-specific antibodies represent other outcomes. Secondary results can provide complementary information, but unadjusted comparisons across multiple outcomes do not automatically confirm the primary result or establish a coherent overall treatment effect.
The status is terminated, and the primary outcome is identified as coming from the first interim analysis. Without the termination reason, full follow-up information, analysis plan, or missing-data methods, it is not possible to determine how those features affect interpretation. The posted confidence interval reflects uncertainty under the reported analysis, not every source of uncertainty about the trial.
In general, statistical uncertainty and clinical importance are related but distinct. A confidence interval can describe the range of effects compatible with the analysis, while clinical importance requires context about what changes in eGFR mean for participants. The registry record does not provide a threshold for clinical importance. No medical decision should be based on these summary figures alone.
14. Why This Trial Matters Statistically
This trial is statistically informative because it puts a continuous kidney-function outcome at the center of a randomized comparison and reports both arm-level estimates and a treatment-difference interval. The result makes the uncertainty visible: the point estimate is negative, but the confidence interval includes zero and extends across values on both sides of it. Reporting the interval, rather than relying only on a single estimate, helps readers distinguish the observed direction from the precision of the evidence.
The record also illustrates why analysis details matter. A least-squares mean depends on a model, but the model specification is not reported. The primary analysis population is defined using treatment exposure and availability of eGFR measurements, while missing-data handling is not described. The study is terminated and the primary endpoint is from the first interim analysis, but the circumstances and analysis plan are not reported. Each fact shapes what can be inferred, even when the numerical result itself is clear.
The secondary outcomes show another common challenge in clinical-trial interpretation: a large outcome set can include measures with different scales and timeframes. Unadjusted estimates from a subset of those outcomes can be useful descriptively, but without a reported multiplicity strategy they should not be elevated to confirmatory evidence. The recalculated planning illustrations also demonstrate that planning estimates based on observed effects depend on assumptions and are not measures of the trial’s achieved power.
For biostatisticians and clinical researchers, the central lesson is to separate the reported estimate, its precision, the analysis assumptions, and the clinical interpretation. The registry supports a careful account of the posted primary result, but it does not supply enough information to reconstruct the full analysis or explain the trial’s termination. Recognizing those boundaries is part of sound statistical reading.
15. 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 trial-specific limitations restrict interpretation of the posted results. The registry lists the study as terminated but does not report why it was terminated, when the decision occurred, or how termination affected recruitment, follow-up, or outcome collection. Because the primary endpoint is identified as coming from the first interim analysis, the absence of details about interim monitoring and the planned analysis sequence is particularly relevant.
The registry provides a primary treatment difference and confidence interval but does not identify the model specification or its covariates. The arm estimates are least-squares means, yet the information needed to reproduce them from the posted summaries is not available. The primary p-value is not reported. The available record therefore supports description of the sponsor-reported estimate, but not an independent reconstruction of its model-based analysis.
The definition of the primary analysis set requires at least 1 dose and both baseline and post-baseline eGFR assessments. The record does not report how many randomized participants were excluded from this set, why any assessment was missing, or how missing data were handled. It also does not provide sensitivity analyses. These gaps make it difficult to assess how the population analyzed compares with all randomized participants or how results might change under other missing-data assumptions.
The multiplicity strategy for the many outcome measures is not reported. Secondary binary recalculations are unadjusted, and the record does not list sponsor comparative analyses for those outcomes. The planning illustrations are based on observed effects and stated assumptions, not on the trial’s own design justification. Finally, safety counts do not identify causality, event timing, or all relevant exposure details. These limitations do not alter the values posted, but they narrow the claims those values can support.
16. Related Tutorials
17. Related Statistical Calculators
18. Sources
- ClinicalTrials.gov: Clazakizumab for the Treatment of Chronic Active Antibody Mediated Rejection in Kidney Transplant Recipients — NCT03744910.
- Registry record last updated 2025-07-23; status last verified 2025-07.
- Results first posted 2025-07-23.
- 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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19. Record Summary
NCT03744910 is a phase 3 randomized, quadruple-masked, parallel-group trial of subcutaneous clazakizumab versus subcutaneous physiologic saline solution in kidney transplant recipients with antibody-mediated rejection. The registry lists enrollment of 194, sponsor CSL Behring, and terminated status.
The primary outcome is change from baseline to week 52 in eGFR. The analysis is described as the first interim analysis and uses an ITT analysis set defined by treatment exposure and availability of baseline and post-baseline eGFR assessments. The reported treatment difference is -2.75, with a 95% confidence interval from -5.84 to 0.35; the interval includes zero.
Secondary outcomes include allograft-related events and laboratory measures. The registry lists 15 posted secondary outcomes among 26 outcome measures. The reason for termination, detailed statistical plan, missing-data methods, and multiplicity strategy are not reported in the registry record.