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 Eculizumab Therapy for Chronic Complement-Mediated Injury in Kidney Transplantation (NCT01327573), a randomized phase 1 study. The primary outcome is Baseline eGFR (Estimated Glomerular Filtration Rate).
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01327573 |
| Phase | Phase 1 |
| Condition | Kidney; Complications, Allograft |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 16 |
| Arms in the primary outcome | 2 |
| Lead sponsor | Sanjay Kulkarni |
| Results posted | Yes |
2. Clinical Question
Population
The study concerns kidney transplant recipients with donor-specific antibodies and worsening kidney function. The registry describes the condition as kidney complications involving the allograft. Enrollment is listed as 16, although the posted arm counts are 10 for Eculizumab and 5 for no Additional Therapy; the record does not explain the difference between those figures.
Intervention
The intervention was eculizumab in addition to standard immunosuppression. The arm description names oral tacrolimus or an equivalent, mycophenolate mofetil, and prednisone as the standard regimen. The record describes the trial as randomized and open-label, with no masking.
Comparator
The comparator was standard immunosuppression without additional therapy. Its description names oral tacrolimus or an equivalent, mycophenolate mofetil, and prednisone. The registry record does not report a post-baseline outcome comparison for this arm against the eculizumab arm.
Primary question
The trial summary describes an aim of assessing eculizumab in transplant recipients with donor-specific antibodies and worsening kidney function, including whether treatment improves endothelial cell injury. However, the primary outcome measure listed in the results is baseline eGFR, not a change in eGFR or a measure of endothelial injury. The posted baseline means and confidence intervals are identical across the two arms, and the record does not report an estimable two-arm analysis. Consequently, the posted primary measure does not answer whether eculizumab altered kidney function or injury after treatment.
3. Trial Design
This was a randomized, open-label, parallel-group pilot intervention trial, listed as Phase 1. The registry status is completed. The record lists a start in 2011-03 and primary completion in 2015-02. Enrollment is recorded as 16. Arm-level outcome counts list 10 for Eculizumab and 5 for no Additional Therapy; the registry record does not explain how these arm counts relate to the enrollment figure.
The Eculizumab arm received eculizumab in addition to standard immunosuppression. The comparator arm received standard immunosuppression without additional therapy. The described background regimen included oral tacrolimus or an equivalent, mycophenolate mofetil, and prednisone. Random allocation can help balance prognostic characteristics across groups, but with a pilot trial and the posted arm counts, chance imbalances may remain. Randomization alone does not establish that the groups were comparable on every characteristic.
Open-label means that masking was not used, according to the registry. Knowledge of assignment can affect care, reporting, or assessment, depending on how outcomes are collected. The registry record does not describe procedures to limit such influences. It also does not report allocation concealment or the method used to generate the allocation sequence.
The trial summary states that investigators intended to assess eculizumab’s effectiveness and endothelial injury. The primary outcome entered in the results, however, is baseline eGFR. The posted results include three outcome measures and one analysis, while the record lists no posted secondary outcomes. These entries do not establish that the stated biological or clinical aims were measured as post-treatment outcomes in the results currently recorded. The protocol, planned follow-up schedule, and reasons for the difference between the stated aims and the posted primary measure 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.
Overall Study
| Stage | Eculizumab | no Additional Therapy |
|---|---|---|
| STARTED | 11 | 5 |
| Received Treatment/Control as Allocated | 10 | 5 |
| COMPLETED | 8 | 4 |
| NOT COMPLETED | 3 | 1 |
Reasons for not completing this period:
| Reason | Eculizumab | no Additional Therapy |
|---|---|---|
| Physician Decision | 3 | 1 |
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 | Eculizumab | no Additional Therapy | Total |
|---|---|---|---|---|
| Participants analysed | 10 | 5 | 15 | |
| Age, Continuous | years | 38 (20 to 57) | 44 (33 to 65) | 43 (20 to 65) |
| Sex: Female, Male: Female | Participants | 3 | 3 | 6 |
| Sex: Female, Male: Male | Participants | 7 | 2 | 9 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Asian | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Black or African American | Participants | 1 | 2 | 3 |
| Race (NIH/OMB): White | Participants | 6 | 2 | 8 |
| Race (NIH/OMB): More than one race | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 3 | 1 | 4 |
| Region of Enrollment: United States | participants | 10 | 5 | 15 |
| C4d Status at Randomization: Positive | participants | 5 | 1 | 6 |
| C4d Status at Randomization: Negative | participants | 5 | 4 | 9 |
| Baseline DSA (Donor Specific Antibody) MFI (mean fluorescent intensity) | MFI | 5000 (2,900 to 13,400) | 3100 (1,100 to 6,000) | 4600 (1,100 to 13,400) |
6. Primary Endpoint
The registry lists the primary outcome as Baseline eGFR (Estimated Glomerular Filtration Rate), measured over Baseline.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | 95% Confidence Interval |
| Unit | mL/min/1.73 m2 |
| Endpoint classification | Continuous Endpoint |
The primary outcome listed is baseline estimated glomerular filtration rate, or eGFR, measured in mL/min/1.73 m2. eGFR is an estimate used to characterize kidney filtration function. A baseline measurement describes kidney function at the start of the outcome assessment; by itself, it does not show a change during treatment or a difference in outcomes after randomization.
The registry reports a mean of 30.04 for Eculizumab, with a 95% confidence interval from 23.77 to 36.31. For no Additional Therapy, it reports the same mean, 30.04, with the same 95% confidence interval, from 23.77 to 36.31. The record identifies the measure as a mean and its uncertainty as a 95% confidence interval. These intervals describe uncertainty around the arm-specific means; they are not ranges containing a specified proportion of individual participants.
Baseline eGFR can help characterize kidney function before treatment and can be useful when interpreting later measurements. A treatment question generally requires an outcome measured after treatment, or a comparison that accounts for baseline values. The registry record does not list a change-from-baseline endpoint or a post-treatment eGFR result as the primary measure. Nor does it report an estimable comparison of the posted arm means. Therefore, these baseline statistics describe the groups at baseline but do not quantify a treatment effect.
The trial summary also refers to endothelial cell injury. The registry record does not identify that measure as the posted primary outcome, and a result for it is not reported in the registry record. The baseline eGFR entry should not be interpreted as a direct measurement of endothelial injury.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The primary results are descriptive baseline summaries. The mean eGFR is 30.04 in each arm, and the reported 95% confidence interval is 23.77 to 36.31 in each arm. The exact match between these posted summaries indicates that the reported baseline group means are the same. It does not show that the treatment groups had identical values for every participant or that their distributions were the same. Group means and confidence intervals cannot reveal all features of individual measurements.
A confidence interval expresses statistical uncertainty about a parameter, here an arm-specific mean, under the assumptions of the method used to calculate it. It is not an interval for individual participant values and is not itself a test of whether treatments differ. Because the reported intervals are identical, they do not supply an estimate of a between-arm treatment contrast. The registry record gives no standard error, test statistic, or p-value for a comparison of the two baseline means. A p-value for that comparison is not reported in the registry record.
Most importantly, baseline measurements precede treatment. Even if an arm difference at baseline had been reported, that would not establish an effect of treatment. Conversely, identical baseline means do not demonstrate that outcomes remained equal after treatment. To evaluate a treatment question, readers would need appropriate post-baseline results and an analysis comparing the randomized groups, with enough information to understand the estimate and its uncertainty. Those results are not reported in the registry record.
The analysis output indicates that a two-arm comparison for this continuous outcome could not be estimated because values were missing or not estimable. Accordingly, no recalculated unadjusted comparison is presented. There is no discrepancy between a recalculated comparison and a sponsor analysis to resolve. The available record does not provide a sponsor-reported treatment-effect estimate for this endpoint either.
Safety entries are descriptive and should be read separately from the primary outcome. The registry lists serious adverse events affecting 4 of 10 at risk in the Eculizumab arm and 3 of 5 at risk in the no Additional Therapy arm. It also lists other adverse events affecting 2 of 10 and 0 of 5, respectively. These counts do not, by themselves, establish that treatment caused an event or that the difference between arms is meaningful. The registry does not provide the detail needed to assess timing, exposure, event definitions, or adjustment for chance variation.
Overall, the posted results establish baseline eGFR summaries and group-level adverse-event counts, but not a comparative estimate of post-treatment benefit or harm. The stated hypothesis about complement inhibition and allograft injury remains a hypothesis in the trial summary; it is not confirmed or refuted by the baseline statistics alone.
9. Statistical Methods Explained
The results characterize baseline eGFR using a mean and a 95% confidence interval. These are descriptive statistics for a continuous measure. A mean represents the arithmetic average of the recorded values within a group. A confidence interval gives a range of values compatible with the data and the assumptions of its calculation for the underlying group mean. It should not be interpreted as a range in which most individual eGFR values fall.
What does a confidence interval convey?
In general, a confidence interval represents the uncertainty associated with estimating a population quantity from a sample. Wider intervals indicate less precision than narrower intervals, all else equal. The interpretation depends on the sampling and statistical assumptions used. The registry identifies the intervals as 95% confidence intervals, but the calculation details and assumptions are not reported in the registry record. The interval from 23.77 to 36.31 is posted for both arms, alongside a mean of 30.04 for each. These arm-specific intervals do not constitute a confidence interval for the difference between arms.
To make an inferential comparison, an analysis would ordinarily estimate a contrast between the groups and quantify uncertainty around that contrast. The contrast could be expressed in different ways depending on the analysis plan. The registry record does not report such an estimate for the listed continuous outcome. It also does not report a standard error, test statistic, or p-value for a two-arm comparison. Because the comparison is not estimable from the posted summary statistics, a recalculated unadjusted estimate is not available. No treatment-effect number can be recovered from identical arm-specific means and intervals alone.
Why is a baseline value different from a treatment effect?
Baseline is the measurement taken before the intervention is evaluated. It describes starting status rather than what happened during follow-up. A treatment effect requires information that compares outcomes under the assigned strategies after treatment, or a suitable comparison of change from baseline. The listed baseline eGFR therefore cannot establish whether kidney function changed, whether the arms diverged, or whether eculizumab affected endothelial injury. The registry record does not report a post-treatment eGFR estimate or a change-from-baseline estimate as the primary outcome.
Randomization is intended to support a fair comparison by assigning participants to treatment strategies independently of known and unknown prognostic factors. In a small pilot study, random variation can still produce differences in baseline characteristics. Baseline summaries can help readers understand the groups, but they do not replace outcome analysis. Nor does the identical reported mean establish participant-level equivalence: different sets of individual values can have the same mean, and the registry does not post participant-level data.
What can be concluded from the unavailable comparison?
The result-processing information states that values were missing or not estimable for a two-arm comparison of the continuous endpoint. This is a limitation of what can be inferred from the posted outcome data, not evidence that the treatment groups had no difference. A missing estimate is not equivalent to an estimate of zero, and it does not indicate a non-significant result. The registry record does not explain whether the limitation arose from unavailable arm-level summaries, a data issue, or another reason. No cause should be inferred.
The planning illustration described for this analysis uses an observed effect, a two-sided significance level of 0.05, equal allocation, and a normal approximation. Such sample-size calculations, when estimable, are planning illustrations about the number of participants per arm that might be needed under stated assumptions. They are not evidence about how much power the completed trial actually had. They are not observed power and cannot compensate for an unavailable treatment-effect estimate. No specific planning estimate is reported in the registry record for this endpoint, and none should be inferred from the baseline means.
General statistical practice also distinguishes a treatment-effect estimate from a significance test. An estimate describes the direction and magnitude of a contrast, while an uncertainty interval communicates its precision. A test addresses compatibility with a specified null hypothesis under assumptions. Neither a p-value nor an interval alone answers whether an effect is clinically important. In this record, the central issue is more basic: the posted primary entry is a baseline measure and no two-arm outcome contrast is available.
Why can over-dispersion matter?
For count or event outcomes, a statistical model may assume a particular relationship between the average event rate and its variability. Over-dispersion means that observed variation exceeds what the model assumes. If ignored, uncertainty can be understated and inference can become too optimistic. That general issue does not create an analysis result for this trial: the primary endpoint is continuous baseline eGFR, and the registry record does not report a model-based comparative analysis for it. The record also does not describe a statistical model for the adverse-event counts.
In summary, the available methods information supports reading the eGFR entries as arm-specific baseline means with confidence intervals. It does not support reconstructing a treatment comparison, a post-treatment trajectory, or an analysis of the trial’s biological hypothesis. Details of the statistical analysis plan, including model choice and handling of repeated measurements, are not reported in the registry record.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists three outcome measures and one analysis, with no posted secondary outcomes. The registry record does not report a multiplicity strategy describing how statistical error across outcomes or analyses was controlled. It also does not report whether the listed outcome measures were prespecified in a protocol or analysis plan, or whether any analyses were exploratory. Without that information, the status and intended inferential role of each measure cannot be fully assessed.
Missing-data handling is not reported in the registry record. The record does not describe the amount or pattern of missing outcome data, reasons for missingness, any imputation procedure, or a sensitivity analysis. It does not state whether all randomized participants contributed to the baseline outcome summaries. The enrollment entry and arm-level counts do not, on their own, establish the analysis population or explain how participants were included in each result.
The record also does not report whether the analysis followed the randomized assignment regardless of treatment received, whether participants were excluded after randomization, or whether a per-protocol or other population was used. Such details matter because excluding participants or handling incomplete measurements differently can affect the comparability created by randomization. No approach should be assumed from the trial’s randomized design alone.
These omissions are especially relevant to interpreting an unavailable two-arm comparison. The record states that the continuous endpoint could not be compared because values were missing or not estimable, but it does not explain the cause or describe a remedy. Consequently, readers cannot determine whether a planned analysis was attempted, whether assumptions were checked, or whether another analysis was intended. Further details about multiplicity, missing data, and analysis populations are not reported in the registry record.
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 |
|---|---|---|---|
| Eculizumab | 4 | 10 | 40.0% |
| no Additional Therapy | 3 | 5 | 60.0% |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Eculizumab | 2 of 10 |
| no Additional Therapy | 0 of 5 |
Most frequent serious adverse event terms
| Event term | Organ system | Eculizumab | no Additional Therapy |
|---|---|---|---|
| Graft Failure | Renal and urinary disorders | 2 of 10 | 1 of 5 |
| Bacterial Infection | Infections and infestations | 1 of 10 | 1 of 5 |
| Viral Infection | Infections and infestations | 1 of 10 | 1 of 5 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Eculizumab | no Additional Therapy |
|---|---|---|---|
| Anemia | Blood and lymphatic system disorders | 1 of 10 | 0 of 5 |
| Viral Infection | Infections and infestations | 1 of 10 | 0 of 5 |
Serious events with the highest arm-level rate: graft failure (20.0%), bacterial infection (20.0%), viral infection (20.0%).
The registry reports serious adverse events affecting 4 of 10 at risk in the Eculizumab arm and 3 of 5 at risk in the no Additional Therapy arm. For other adverse events, it reports 2 of 10 at risk in the Eculizumab arm and 0 of 5 at risk in the comparator arm. These are descriptive arm-level counts. They should not be treated as proof that treatment caused an event, nor do they establish a reliable difference in risk between the groups.
The listed serious event terms are Graft Failure, Bacterial Infection, and Viral Infection, each reported as 20.0%. The registry record does not provide event-level details, timing, duration, severity grading, or the method used to attribute events. It also does not report death counts for the arms. The terms and percentages therefore offer limited context and should not be treated as a complete account of safety outcomes.
Interpretation is further limited by the small posted arm counts and the absence of a comparative safety analysis. A difference in observed counts can arise by chance, and counts alone do not quantify uncertainty. The registry does not report an exposure-adjusted analysis or enough follow-up detail to compare event rates over time. These safety entries should be read as recorded observations, not as a causal estimate or a basis for treatment decisions.
12. What the Result Does, and Does Not, Mean
The registry record documents a randomized, open-label pilot trial of eculizumab added to standard immunosuppression versus standard immunosuppression without additional therapy. It reports baseline eGFR means of 30.04 in both arms, with 95% confidence intervals from 23.77 to 36.31 for each. It also records adverse-event counts. Those entries describe the posted data; they do not supply an estimated effect of eculizumab on kidney function, endothelial injury, or allograft outcomes.
The identical baseline summaries do not show that treatment groups remained alike after therapy. Baseline is not a follow-up outcome. Because the registry does not report an estimable two-arm comparison for the continuous measure, there is no posted treatment contrast to interpret, and no confidence interval for a treatment effect. The absence of an estimate does not mean that the treatment effect was zero, that the groups were equivalent, or that a statistical test found no difference.
The trial summary’s hypothesis is that complement inhibition may reduce allograft injury through reduced complement-mediated endothelial injury and activation. That statement describes the investigators’ rationale, not a result established by the baseline eGFR entries. A result for endothelial injury is not reported in the registry record. Likewise, the posted material does not provide the post-treatment outcome information needed to determine whether the stated clinical or biological aims were met.
The serious and other adverse-event counts describe events recorded in each arm, but they are not causal estimates. The record does not provide sufficient detail to assess when events occurred, how they were classified, or how uncertainty in the arm comparison was handled. The counts can inform a descriptive reading of what was recorded, but they cannot establish comparative safety from this information alone.
Thus, the defensible interpretation is narrow: the registry gives baseline eGFR summaries and selected safety counts for a completed pilot trial. It does not establish benefit, lack of benefit, equivalence, or a causal safety difference. A fuller assessment would require post-baseline results, outcome definitions, analysis methods, missing-data information, and the relevant uncertainty estimates; these are not reported in the registry record.
13. Why This Trial Matters Statistically
This trial raises a useful statistical distinction between a study’s scientific question and the outcomes that appear in its results record. The summary describes an interest in eculizumab, allograft injury, and endothelial cell injury, while the listed primary outcome is baseline eGFR. A baseline measurement can characterize participants, but it is not by itself a measure of what the intervention changed. Recognizing that distinction prevents descriptive starting values from being mistaken for evidence about treatment effects.
The record also illustrates why an arm-specific confidence interval is not a substitute for a confidence interval around a treatment contrast. Identical means and intervals provide descriptive information about the posted baseline values. They do not yield an estimate of the difference in post-treatment outcomes, and they do not demonstrate equivalence. When a two-arm continuous comparison is unavailable, the appropriate interpretation is that the comparison cannot be evaluated from the posted result, rather than that it is null.
Pilot trials can contribute information about feasibility and generate hypotheses, but their interpretation depends on the outcomes and analyses actually reported. Randomization supports comparative inference when outcomes are collected and analyzed appropriately; it does not make an incomplete outcome record conclusive. The listed safety counts similarly show why descriptive event totals should not be recast as causal evidence without definitions, follow-up context, and uncertainty assessment.
For biostatisticians and clinical researchers, the key lesson is to align the estimand, endpoint timing, analysis population, and reported result. The registry’s stated biological rationale, baseline outcome entry, and adverse-event summaries answer different questions. Keeping those distinctions clear preserves what the record can support while making the missing evidence visible.
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 primary endpoint entry is baseline eGFR, although the study summary describes assessing eculizumab and endothelial cell injury. The registry record does not explain this difference or report a post-treatment primary outcome result. The posted baseline summaries are identical between arms, but no estimable two-arm comparison is available. This sharply limits interpretation of treatment effects.
The record lists enrollment as 16, while the posted arm counts are 10 for Eculizumab and 5 for no Additional Therapy. It does not explain the relationship between enrollment and these outcome counts, or identify the analysis population. The reason for the unavailable continuous comparison is also not reported beyond the statement that values were missing or not estimable.
Further details needed for a fuller appraisal are not reported in the registry record: the allocation sequence method, allocation concealment, outcome measurement procedures, follow-up schedule, statistical analysis plan, handling of missing data, multiplicity approach, and whether analyses followed randomized assignment. The record also does not provide participant-level results or a post-baseline eGFR analysis. The open-label design means masking was absent, but the registry does not describe whether outcome assessment could be influenced by knowledge of assignment.
Safety interpretation is limited by the absence of event timing, detailed definitions, exposure context, and comparative uncertainty estimates. Death counts are not reported in the registry record. The listed serious-event terms and percentages therefore do not constitute a complete safety analysis. These limitations mean that the registry supports a description of selected entries, not a definitive assessment of efficacy or comparative safety.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Eculizumab Therapy for Chronic Complement-Mediated Injury in Kidney Transplantation — NCT01327573.
- Registry record last updated 2019-08-12; status last verified 2019-07.
- Results first posted 2019-08-12.
- 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
NCT01327573 is a completed, randomized, open-label, parallel-group Phase 1 pilot trial. It compared eculizumab added to standard immunosuppression with standard immunosuppression without additional therapy in kidney transplant recipients described as having donor-specific antibodies and worsening kidney function. Enrollment is listed as 16; posted arm counts are 10 and 5.
The primary outcome recorded is baseline eGFR. Both arms have a posted mean of 30.04 and a 95% confidence interval from 23.77 to 36.31. A two-arm continuous comparison is not estimable from the posted data, and a post-treatment eGFR result or endothelial injury result is not reported in the registry record. Serious and other adverse-event counts are listed, but the record does not provide enough context for a causal safety comparison. Overall, the posted results describe baseline values and selected events, not a comparative treatment effect.