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 in Highly-HLA Sensitized Patients Awaiting Renal Transplant (NCT03380962), a na phase 1, phase 2 study. The primary outcome is Number of Treatment Related Adverse Effects of Clazakizumab Therapy (18 Month Period).
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT03380962 |
| Phase | Phase 1, Phase 2 |
| Condition | Kidney Failure, Chronic, End-Stage Renal Disease, Transplant Glomerulopathy |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 20 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Stanley Jordan, MD |
| Results posted | Yes |
2. Clinical Question
Population
The trial concerns highly-HLA sensitized patients awaiting renal transplant. The registry describes people with a previous allograft failure as a group that may be unlikely to receive another transplant without desensitization. Eligible ages are described as 15-75. The registry lists 20 participants enrolled at a single center.
Intervention
Participants received clazakizumab, an anti-IL-6 monoclonal antibody, as desensitization therapy. The planned regimen was monthly dosing, with up to 6 doses before transplantation. For participants transplanted during the study, the description specifies 6 monthly post-transplant doses, followed by a protocol biopsy at 6 months. Further doses were conditional on improvements after the 6th post-transplant dose; the description also refers to a 12-month protocol biopsy after 12 post-transplant doses.
Comparator
There was no separate comparator group. The trial is listed as single-group, open-label, and without randomized allocation. The registry describes all participants as receiving clazakizumab, so the design does not provide a concurrent control group for separating treatment effects from other influences.
Primary question
The primary endpoint asks for the number of treatment-related adverse effects associated with clazakizumab therapy over an 18-month period, described as 6 months pre-transplant and 12 months post-transplant. The registry also lists outcomes involving donor-specific antibodies, estimated glomerular filtration rate, and antibody-mediated rejection. The primary endpoint is a safety measure; it is not, by itself, a test of whether desensitization improves transplant access or outcomes.
3. Trial Design
The registry identifies NCT03380962 as a phase I/II, single-center, exploratory study of clazakizumab in highly-HLA sensitized patients awaiting renal transplant. Its title and description place the study in the context of desensitization before a possible HLA-incompatible transplant. The registry lists an enrollment of 20 and a completed status. The start date is 2018-02-27, and the primary completion date is 2025-08-30.
The design is single-group and open-label, with allocation listed as not applicable. There is no randomized comparator arm. The intervention is clazakizumab, administered monthly. The description allows up to 6 doses before transplantation. If a participant receives a transplant during the study, the described plan includes 6 additional monthly doses and a 6-month protocol biopsy. Further treatment is conditional on improvements after the 6th post-transplant dose; the registry description also specifies a 12-month protocol biopsy for participants receiving 12 post-transplant doses. The record additionally mentions non-protocol biopsies for cause in participants with persistent allograft dysfunction.
The primary outcome is the number of treatment-related adverse effects over the stated 18-month period. Listed secondary outcomes include changes in class I and class II donor-specific antibody mean fluorescence intensity after transplant, estimated glomerular filtration rate at 12 months post-transplant, and the number of antibody-mediated rejection episodes. The record lists 5 outcome measures and 0 analyses. A detailed statistical analysis plan, including the planned methods for those outcomes, is not reported in the registry record. The rationale for the enrollment target and any sample-size justification are also not reported in the registry record.
Because every participant is assigned to the same intervention, the design can describe outcomes observed during treatment but cannot make a randomized comparison with an untreated or alternative-treatment group. Open-label treatment also means participants and study staff are not masked to the intervention, according to the registry. Those design features matter when interpreting subjective event reporting and any changes that could also occur over time or alongside other care.
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 | Clazakizumab |
|---|---|
| STARTED | 20 |
| COMPLETED | 20 |
| NOT COMPLETED | 0 |
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 | Clazakizumab |
|---|---|---|
| Participants analysed | 20 | |
| Age, Continuous | years | 44.15 (SD 11.5) |
| Sex: Female, Male: Female | Participants | 9 |
| Sex: Female, Male: Male | Participants | 11 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 |
| Race (NIH/OMB): Asian | Participants | 2 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 |
| Race (NIH/OMB): Black or African American | Participants | 7 |
| Race (NIH/OMB): White | Participants | 11 |
| Race (NIH/OMB): More than one race | Participants | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| Region of Enrollment: United States | participants | 20 |
| Baseline Mean Fluorescence Intensity (MFI), Class I antibodies, pre-transplant | MFI | 12372 (SD 3721) |
| Baseline Mean Fluorescence Intensity (MFI), Class II antibodies, pre-transplant | MFI | 13526 (SD 3689) |
6. Primary Endpoint
The registry lists the primary outcome as Number of Treatment Related Adverse Effects of Clazakizumab Therapy (18 Month Period), measured over 18 months (6 months pre-transplant and 12 months post-transplant).
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | adverse events related to treatment |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is the number of treatment-related adverse effects associated with clazakizumab therapy during an 18-month period. The registry describes this period as 6 months before transplantation and 12 months after transplantation. It says adverse-event data were collected while participants received monthly clazakizumab, with up to 6 pre-transplant doses and, for those transplanted during the study, up to 12 post-transplant doses.
A safety endpoint is used to characterize unwanted events observed during exposure to an intervention. Counting events can describe the overall burden of reported events, while counting participants affected answers a different question: how many people experienced one or more events. One participant may experience multiple events, so these measures are not interchangeable. The registry’s primary endpoint is worded as a number of adverse effects, but a single aggregate numerical result for that endpoint is not reported in the registry record. The posted safety summaries instead give participants at risk and affected for serious and other adverse events.
The stated monitoring period should not be read as proof that every participant contributed the same length of observation. The regimen and post-transplant follow-up depend on whether transplantation occurred, and further post-transplant doses are described as conditional. The registry does not report participant-level exposure time or a rate accounting for differing time at risk. Consequently, the endpoint description identifies the safety question and intended observation window, but does not by itself establish the amount of exposure or the event rate for each participant.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry describes a small, single-group study with 20 enrolled participants. Its posted adverse-event summaries list 20 participants at risk for serious adverse events and 8 affected; for other adverse events, 20 were at risk and 9 were affected. The record lists 0 deaths. These are descriptive counts within the treated group. They do not show how frequently similar events would have occurred without clazakizumab, nor do they establish that treatment caused an event.
The serious-event terms listed include Urinary Tract Infection at 20.0%, Elevated creatinine at 15.0%, Bacteremia at 5.0%, Abdominal pain at 5.0%, Perinephric fluid collection with bacteremia and UTI at 5.0%, and Graft failure due to renal vein thrombosis at 5.0%. These listed terms describe the registry’s serious-event summary. The percentages should not be added together: the record does not say that the terms are mutually exclusive, and a participant may have experienced more than one event. Nor does the list give enough information to infer the timing, duration, recurrence, or relatedness of each listed event.
The primary endpoint concerns treatment-related adverse effects, but the registry’s posted safety summary separates serious and other adverse events and does not give one overall count for the primary endpoint. The serious-event summary therefore should not be treated as the complete primary-outcome result or as evidence that every listed event was judged treatment-related. A detailed event-level attribution is not reported in the registry record.
No inferential analyses are listed in the registry, and it reports no confidence interval or p-value for the safety summaries. This limits how precisely the observed counts can be generalized beyond the enrolled participants. A confidence interval, in general, expresses uncertainty around an estimated quantity; without one, the posted counts remain descriptive observations rather than a quantified estimate of uncertainty.
The open-label single-group design is central to interpretation. Without a concurrent comparator, differences from an expected background level of events cannot be separated from treatment effects using this trial alone. The study’s focus on safety and exploratory outcomes also differs from a controlled efficacy comparison. The registry lists antibody, kidney-function, and rejection outcomes, but numerical results for those outcomes are not reported in the record. The record therefore supports a description of the design and the posted safety counts, not a conclusion about comparative benefit or harm.
9. Statistical Methods Explained
The registry describes an open-label, single-group phase I/II study. That design determines what kinds of statistical conclusions are available. Since there is no separate randomized comparator, the primary analyses that can be described from the design are within-group summaries: how many participants or events were observed, and how outcomes changed over time if repeated measurements were collected and reported. A treatment-versus-control contrast is not available from the listed design.
What does a single-group result describe?
General statistical context: a single-group summary reports what happened among the participants who received the intervention. It can be useful for characterizing observed safety events and describing outcomes in the enrolled group. It cannot, by itself, distinguish an intervention effect from background risk, changes over time, participant characteristics, or other care. Random allocation to a concurrent comparator is one approach to reducing some of those uncertainties, but this registry record does not describe such an allocation.
The record lists 20 enrolled participants, and the adverse-event summaries give 20 as the number at risk for both serious and other events. Those counts provide the denominators stated in the safety summary. They do not establish that each person had the same duration of exposure or observation. The regimen could involve pre-transplant dosing and, for participants transplanted during the study, post-transplant dosing. The registry does not provide individual follow-up durations or person-time for the adverse-event summaries.
Why distinguish events from participants?
General statistical context: an event count and a count of affected participants answer different questions. A person can have more than one event, and a single event description may occur in more than one person. A participant-level count is useful for reporting how many people had at least one event; an event-level count describes the number of occurrences. The primary endpoint is worded as a number of treatment-related adverse effects, whereas the posted safety summaries report participants at risk and affected. Because an aggregate numerical primary-endpoint result is not reported in the registry record, those participant summaries should not be substituted for a total event count.
Counts may be analyzed using statistical models designed for count outcomes, but the appropriate method depends on the outcome definition, data distribution, follow-up, and analysis plan. General statistical context: a Poisson model is often used for counts under assumptions about the relationship between the mean and variance and the event-generating process. Over-dispersion occurs when variation in the counts is greater than such a model expects; if present and ignored, uncertainty estimates may be too small. These are general considerations only. The statistical model, any assessment of over-dispersion, and any adjustment for exposure time are not reported in the registry record.
What can uncertainty estimates add?
General statistical context: a confidence interval gives a range of values compatible with the observed data under a specified statistical model and reflects sampling uncertainty. It does not guarantee that the range contains a true value, and it does not remove bias from study design or incomplete measurement. A p-value, when used, describes the compatibility of data with a specified null model; it is not a measure of clinical importance or the probability that a hypothesis is true. The registry lists 0 analyses and reports no confidence intervals or p-values for the adverse-event summaries, so those inferential interpretations are not available for the posted counts.
For outcomes measured repeatedly, a statistical approach may need to account for the fact that measurements from the same participant are related. General statistical context: treating repeated observations as independent can understate uncertainty because outcomes within a person may be correlated. The registry lists post-transplant antibody measures and kidney function at 12 months, but the analysis method for repeated or follow-up measurements is not reported in the registry record. No estimates of change for these secondary outcomes are included in the record.
How should the design shape interpretation?
General statistical context: masking can reduce some influences on assessment and reporting, especially when outcomes involve judgment. This trial is listed as open-label, so participants and study staff knew the assigned intervention. That fact does not establish that any particular outcome was biased; it identifies a potential source of influence that readers should consider. Likewise, an exploratory phase I/II designation describes the trial’s stated phase, but does not reveal the statistical plan or establish that a particular analysis was prespecified.
The protocol description includes treatment and follow-up contingent on transplantation and post-transplant findings. Such variation can affect the amount of exposure and the time during which events can be observed. General statistical context: comparing raw counts across people with different time at risk may be misleading if exposure duration differs; event rates may require an appropriate denominator and assumptions about how events accrue over time. The registry does not report an exposure-adjusted rate or the method used to handle differing observation periods.
Finally, the registry does not report a statistical analysis plan, interim analyses, missing-data procedures, or defined analysis populations. It is therefore not possible to determine from the record whether analyses were planned as intention-to-treat, per-protocol, or another approach, or how incomplete follow-up was handled. The absence of reported methods is an important limit on evaluating precision and robustness; it is not evidence that a particular method was or was not used outside the registry record.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists 5 outcome measures, including the primary safety endpoint and secondary measures involving class I and class II donor-specific antibodies, estimated glomerular filtration rate, and antibody-mediated rejection episodes. It lists 0 analyses. A detailed statistical analysis plan, including the order of testing, any adjustment for multiple comparisons, and the distinction between confirmatory and exploratory analyses, is not reported in the registry record.
General statistical context: when several outcomes or repeated comparisons are examined, the chance of at least one apparently unusual result can increase if each is assessed separately without a plan for multiplicity. Procedures for addressing multiplicity can control error rates or prioritize interpretation, but they depend on the intended hypotheses and analysis strategy. No such procedure is reported, so there is no basis for asserting that the secondary outcomes were adjusted or that they were intended as formal hypothesis tests.
The registry record does not report missing-data procedures, participant flow by outcome, or the analysis population for each endpoint. It therefore does not establish how missing measurements, missed visits, incomplete follow-up, or participants who did not proceed to transplantation were handled in analyses. The treatment description makes post-transplant dosing and biopsies conditional on transplantation and subsequent findings, but the record does not provide enough information to determine how these conditions affected outcome availability or analysis inclusion.
General statistical context: missing data can reduce precision and can also introduce bias if the likelihood of missingness is related to participants’ outcomes or characteristics. The direction and size of any such effect cannot be determined without information about the missingness pattern and analysis method. These issues should be distinguished from the posted event counts, which are descriptive summaries with stated at-risk denominators.
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 |
|---|---|---|---|
| Clazakizumab | 8 | 20 | 40.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Clazakizumab | 0 of 20 |
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 | 9 of 20 |
Most frequent serious adverse event terms
| Event term | Organ system | Clazakizumab |
|---|---|---|
| Urinary Tract Infection | Renal and urinary disorders | 4 of 20 |
| Elevated creatinine | Renal and urinary disorders | 3 of 20 |
| Bacteremia | Infections and infestations | 1 of 20 |
| Abdominal pain | Gastrointestinal disorders | 1 of 20 |
| Perinephric fluid collection with bacteremia and UTI | Renal and urinary disorders | 1 of 20 |
| Graft failure due to renal vein thrombosis | Renal and urinary disorders | 1 of 20 |
| Transplant nephrectomy | Renal and urinary disorders | 1 of 20 |
| Perinephric abscess | Renal and urinary disorders | 1 of 20 |
| Hematuria | Renal and urinary disorders | 1 of 20 |
| Covid-19 | Infections and infestations | 1 of 20 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Clazakizumab |
|---|---|---|
| Thrombocytopenia | Blood and lymphatic system disorders | 4 of 20 |
| Edema | Renal and urinary disorders | 3 of 20 |
| Surgical site incision pain | Surgical and medical procedures | 3 of 20 |
| Anemia | Blood and lymphatic system disorders | 3 of 20 |
| Itching/rash | Skin and subcutaneous tissue disorders | 3 of 20 |
| COVID-19 | Infections and infestations | 2 of 20 |
| Elevated creatinine | Renal and urinary disorders | 2 of 20 |
| Diarrhea | Gastrointestinal disorders | 2 of 20 |
| Hyperkalemia | Metabolism and nutrition disorders | 2 of 20 |
| Right wrist pain | Musculoskeletal and connective tissue disorders | 1 of 20 |
Serious events with the highest arm-level rate: urinary tract infection (20.0%), elevated creatinine (15.0%), bacteremia (5.0%), abdominal pain (5.0%), perinephric fluid collection with bacteremia and uti (5.0%).
The registry lists 8 participants affected by serious adverse events among 20 at risk, and 9 affected by other adverse events among 20 at risk. It also lists 0 deaths. These figures describe participants, not necessarily the total number of events: a participant may have experienced more than one event. The record does not report a single total count of treatment-related adverse effects for the primary endpoint.
The serious-event terms and percentages include Urinary Tract Infection at 20.0%, Elevated creatinine at 15.0%, Bacteremia at 5.0%, Abdominal pain at 5.0%, Perinephric fluid collection with bacteremia and UTI at 5.0%, and Graft failure due to renal vein thrombosis at 5.0%. The percentages are registry summaries, and the record does not specify whether event terms overlap. They should not be summed or interpreted as separate groups of participants.
These observations do not establish that clazakizumab caused any particular event. Attribution details, event timing, duration, recurrence, and event-level denominators are not reported in the registry record. The serious-event summary also does not replace the primary endpoint, which is worded as treatment-related adverse effects over the stated 18-month period.
12. What the Result Does, and Does Not, Mean
The registry record describes a completed, open-label, single-group study of clazakizumab in highly-HLA sensitized patients awaiting renal transplant. It lists 20 enrolled participants and reports descriptive safety summaries: 8 of 20 participants at risk were affected by serious adverse events, 9 of 20 by other adverse events, and 0 deaths. The listed serious-event terms provide additional descriptive detail, but the record does not establish whether those terms overlap or whether each event was attributed to treatment.
These results do not establish a causal treatment effect. In a single-group study, observed events cannot be compared with outcomes under a concurrent control condition. The record also does not give a complete numerical result for the primary endpoint as worded, which is the number of treatment-related adverse effects during the stated observation period. Nor does it report inferential estimates, confidence intervals, or p-values for the safety summaries.
The trial’s listed secondary outcomes concern donor-specific antibodies, estimated glomerular filtration rate, and antibody-mediated rejection. Numerical results for those measures are not reported in the registry record. Thus, the available information does not support a conclusion about changes in antibody measures, kidney function, rejection frequency, or comparative transplant outcomes.
General statistical context: observed safety counts can help describe the experience of participants in a study, but they do not establish the frequency expected in a broader population, especially when the sample is limited and there is no control group. A lack of a reported statistical estimate does not mean that an effect is absent; it means the registry record does not provide that estimate. The most defensible interpretation is therefore bounded: these are descriptive summaries from the participants at risk in this study, not proof of causation, comparative safety, or clinical benefit.
13. Why This Trial Matters Statistically
This trial is statistically informative as an example of how to read an early-phase, open-label, single-group study without treating its observations as a controlled comparison. The registry identifies a population with substantial transplant-related challenges and describes a desensitization regimen linked to possible transplantation and subsequent follow-up. That context helps explain why the study’s safety monitoring and exploratory outcomes are of interest, while the design limits the strength of causal conclusions.
The distinction between the primary endpoint and the posted safety summaries is important. The primary endpoint is worded as a number of treatment-related adverse effects over an 18-month period. The posted summaries instead give numbers of participants at risk and affected by serious and other adverse events. Keeping the event-level and participant-level questions separate prevents a participant count from being mistaken for a total event count, or a general safety summary from being treated as the full primary-endpoint result.
The study also illustrates why observation time matters for count outcomes. The described treatment course can vary with transplantation and subsequent findings. Without participant-level exposure time or a reported rate model, raw counts cannot describe event incidence per unit of time. The record does not report such an adjustment, so interpretation should remain tied to the stated denominators and summaries.
Finally, the listed secondary outcomes span different clinical measurements and event counts. The registry provides their names but does not report numerical results or analysis methods for them. That gap makes it especially important to separate a planned or listed outcome from a result that can actually be interpreted. The record supports careful descriptive reading of safety data, while leaving comparative effects, precision, multiplicity handling, and missing-data methods unresolved.
14. Limitations
- The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
- Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.
The principal limitation is the single-group design: there is no randomized or concurrent comparator to separate treatment effects from other explanations for observed outcomes. The study is open-label, and masking is listed as none. This may matter for event recognition or reporting, although the registry does not show that any specific assessment was affected.
The enrollment is 20, and the posted safety summaries are counts within that group. The registry gives no confidence intervals, p-values, or other inferential estimates for those summaries. It also lists 0 analyses. The record does not report an aggregate numerical result for the primary endpoint as worded, even though it gives serious and other adverse-event participant counts.
The treatment and monitoring schedule can depend on transplantation and later findings. The record does not report individual exposure durations, participant-level time at risk, or exposure-adjusted event rates. It also does not report how many participants underwent transplantation or completed each follow-up element. These omissions limit interpretation of the 18-month endpoint description as a uniform observation period for every participant.
Event attribution and detail are limited in the registry summary. It does not provide event-level counts, timing, duration, recurrence, or an explanation of whether the listed serious-event terms overlap. The listed percentages should therefore be read as reported, without inferring a total burden or treatment causality.
Finally, statistical methods for the listed outcomes, analysis populations, missing-data handling, multiplicity procedures, interim analyses, and the rationale for the enrollment target are not reported in the registry record. Numerical results for the secondary antibody, kidney-function, and rejection outcomes are also not reported in the record. These limitations constrain assessment of precision, robustness, and outcome-specific conclusions.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Clazakizumab in Highly-HLA Sensitized Patients Awaiting Renal Transplant — NCT03380962.
- Registry record last updated 2026-10-30; status last verified 2026-10.
- Results first posted 2026-10-30.
- 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
NCT03380962 is listed as a completed phase I/II, single-center, open-label, single-group study of clazakizumab in highly-HLA sensitized patients awaiting renal transplant. Enrollment is listed as 20. The registry describes monthly dosing, with up to 6 doses before transplantation and conditional post-transplant treatment and biopsies.
The primary endpoint is the number of treatment-related adverse effects during an 18-month period. The posted safety summaries list 8 of 20 participants at risk affected by serious adverse events, 9 of 20 affected by other adverse events, and 0 deaths. The record lists 5 outcome measures and 0 analyses. It does not report a numerical aggregate result for the primary endpoint, inferential estimates for the safety summaries, or numerical results for the listed secondary outcomes.
Without a comparator group, these observations are descriptive and do not establish causation or comparative treatment effects. Statistical methods, missing-data procedures, and the analysis plan are not reported in the registry record.