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 Observational Study to Investigate the Long-term Effects of MIRCERA in Clinical Routine (NCT01309269), a registered phase not stated study. The primary outcome is Hemoglobin Levels at Monthly Intervals.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01309269 |
| Phase | Phase not stated |
| Condition | Anemia |
| Allocation | Not Stated |
| Design model | Not Stated |
| Masking | Not Stated |
| Enrollment | 1083 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Hoffmann-La Roche |
| Results posted | Yes |
2. Clinical Question
Population
People with chronic kidney disease and renal anemia receiving care in clinical routine. The registry reports enrollment of 1083 participants. The primary outcome population is described as participants with at least 1 hemoglobin value documented after their first application of methoxy polyethylene glycol-epoetin beta during the study course. The complete wording of the population definition is not reported in the registry record.
Intervention
Long-term treatment with MIRCERA, identified in the registry as methoxy polyethylene glycol-epoetin beta. This is an observational study of treatment in routine clinical care, not a randomized assignment to treatment.
Comparator
No separate control group or comparator is described. The registry lists a cohort and does not state an allocation method. There is therefore no like-for-like control comparison to use for estimating a relative treatment effect.
Primary question
The study set out to assess hemoglobin levels at monthly intervals from prior to Day 1 through Month 24. The registry identifies the outcome as a mean measured in g/dL, with standard deviation as the measure of dispersion. Numerical results for those measurements are not reported in the registry record.
The central question is descriptive: how hemoglobin levels were recorded over time among participants treated with MIRCERA in routine care. The registry summary says data would be collected from each patient for at least 24 months. That planned observation period does not establish how many participants completed follow-up or contributed a measurement at every scheduled time. Those details are not reported in the registry record.
Because treatment was not randomly assigned and no comparison cohort is described, the study cannot by itself separate changes in hemoglobin over time from other influences on participants’ health or care. Its question concerns the observed course in the enrolled cohort, rather than a randomized comparison of MIRCERA against another treatment or no treatment.
3. Trial Design
This completed study is identified as observational and non-interventional. Its title describes investigation of the long-term effects of MIRCERA in clinical routine, and its summary specifies chronic kidney disease patients with renal anemia. Hoffmann-La Roche is listed as the sponsor. The registry gives a start date of 2010-09 and a primary completion date of 2014-04, with status recorded as COMPLETED.
The registry reports enrollment of 1083 participants and lists a cohort, without a separate treatment or control arm. Allocation is not stated. In this design, researchers observe care as it occurs rather than assigning participants to treatment groups through randomization. As a result, the record does not describe a randomized treatment contrast or a like-for-like control comparison. A causal effect cannot be inferred simply by observing measurements in this cohort.
The planned data collection was at least 24 months per patient. The primary outcome schedule includes a measurement prior to Day 1 and measurements at Months 1 through 24. The registry does not report whether all participants were followed for the full planned period, the number contributing data at each time point, or the amount of missing follow-up.
The record lists 3 outcome measures and 0 analyses. It does not report a detailed statistical analysis plan, an allocation procedure, a sample-size justification, or any interim analyses. These omissions mean that the design can be described from the registry entries, but the analytical choices and conduct cannot be reconstructed beyond what is recorded. The completed status indicates the registry’s study status; it does not supply the numerical results needed to assess the pattern or precision of hemoglobin measurements.
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: In this non-interventional study, physician was completely free in his/her decision which participants he/she treated with the medication selected in this study, what dosage was chosen, which diagnostic measures were taken, how the course of treatment was monitored and what accompanying or supplemental medications were prescribed.
Overall Study
| Stage | Methoxy Polyethylene Glycol-epoetin Beta |
|---|---|
| STARTED | 1085 |
| Treated | 978 |
| COMPLETED | 245 |
| NOT COMPLETED | 840 |
Reasons for not completing this period:
| Reason | Methoxy Polyethylene Glycol-epoetin Beta |
|---|---|
| Adverse Event | 56 |
| Withdrawal by Subject | 25 |
| Lack of Acceptance | 15 |
| Other Erythropoiesis-stimulating Agents | 119 |
| Kidney Transplant | 25 |
| Administrative Problems | 141 |
| Other | 256 |
| Other | 1 |
| Study Completion Data Not Recorded | 95 |
| Enrolled but not Treated | 107 |
Analysis population for the primary outcome, as defined in the registry: Effectiveness Population I: all participants for whom at least 1 hemoglobin value was documented after the first application of methoxy polyethylene glycol-epoetin beta during the study course. N (number of participants analyzed) = participants evaluable for this measure. n = participants with hemoglobin values during study period considered.
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: Safety Analysis Set: all participants who received at least 1 dose of methoxy polyethylene glycol-epoetin beta during the study course.
| Characteristic | Unit | Methoxy Polyethylene Glycol-epoetin Beta |
|---|---|---|
| Participants analysed | 978 | |
| Age, Continuous | years | 67.0 (SD 13.9) |
| Gender: Female | Participants | 428 |
| Gender: Male | Participants | 550 |
6. Primary Endpoint
The registry lists the primary outcome as Hemoglobin Levels at Monthly Intervals, measured over Prior to Day 1, Months 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, and 24.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Deviation |
| Unit | g/dL |
| Endpoint classification | Continuous Endpoint |
The primary outcome is hemoglobin level, measured in g/dL and summarized as a mean with standard deviation. Measurements were scheduled prior to Day 1 and at Months 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, and 24. The registry says hemoglobin levels were measured as grams per deciliter.
In general, a mean gives a summary of the central level of a continuous measurement across the participants who contribute data. A standard deviation describes how dispersed individual measurements are around that mean. These summaries answer different questions: the mean describes the group’s average level, while the standard deviation describes variation among measurements. Neither summary alone shows the full distribution or the experience of every participant.
The registry’s outcome description connects the measure to the stated aim of assessing long-term treatment effects in chronic kidney disease patients with renal anemia. A series of measurements could describe how the cohort’s recorded hemoglobin levels vary over the planned follow-up. However, the numerical means, standard deviations, and participant counts at the scheduled time points are not reported in the registry record. No direction, size, or precision of change can therefore be assessed from the outcome description alone.
The defined population includes participants with at least 1 recorded hemoglobin value after their first application during the study course. The full description is truncated in the registry record. That makes it important not to assume that the analysis included every enrolled participant or that each participant contributed measurements at all scheduled visits.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The available record establishes the study question and measurement schedule, but does not provide the numerical hemoglobin results. It names the primary outcome, unit, summary measure, dispersion measure, and time points. It does not give means, standard deviations, confidence intervals, p-values, or participant counts at each measurement time. Consequently, no trend in hemoglobin, difference between time points, or estimate of uncertainty can be described from the registry record.
The study is observational and has a cohort rather than a stated randomized comparison. Its records can describe measurements among participants receiving MIRCERA in routine care, but they do not establish what would have happened to those same participants under a different treatment strategy. Without a separate comparator, changes across time may reflect treatment and other factors that also change during follow-up. The record does not report analyses intended to address such factors.
The enrollment figure is 1083, but that figure should not be read as the number contributing to the primary endpoint at every scheduled time. The outcome population is defined by having at least 1 post-application hemoglobin value, and the registry’s wording for that population is incomplete. Counts analyzed at individual time points are not reported in the registry record. This distinction matters because a mean at a given time is based on participants with available measurements at that time, and that set can differ from the set contributing at another time.
The outcome uses a mean and standard deviation, which are useful descriptive summaries but do not, on their own, indicate whether a change is statistically distinguishable from random variation or clinically important. Those judgments require the actual estimates, their uncertainty, and a suitable analytical context. None of those numerical outcome results are reported in the registry record.
The record lists 0 analyses. It therefore offers no reported inferential result to interpret and no sponsor analysis to compare with a recalculation. Any planning illustration based on an observed effect would also require a numerical observed effect; such an effect is not reported in the registry record. A planning calculation would describe assumptions for a hypothetical future study, not observed power or evidence about the outcome in this cohort.
The appropriate reading is limited: the trial was designed to follow hemoglobin measurements during long-term routine use, but its numerical primary outcome findings are not reported in the registry record. The completed status and enrollment count do not substitute for those results. No conclusion about the magnitude, direction, precision, or cause of any hemoglobin change can be drawn from the information recorded.
9. Statistical Methods Explained
What does the mean describe?
In general, the mean is a way to summarize the central level of a continuous variable. For this study, the continuous measure is hemoglobin in g/dL, and the registry identifies the mean as the summary parameter. A mean is calculated from the measurements available for the relevant group and time point. It is informative as a group-level summary, but it does not show how each participant’s measurement changed or whether values cluster closely around the average.
The registry pairs the mean with a standard deviation. In general, standard deviation describes the spread of observations around the mean, on the same measurement scale. It is not the same as a confidence interval: a standard deviation describes variability among observed measurements, whereas a confidence interval expresses uncertainty about an estimated quantity. The record does not report either the numerical standard deviations or confidence intervals for the hemoglobin outcome.
Why does the measurement schedule matter?
The scheduled measurements run from prior to Day 1 through Month 24. Repeated measurements make it possible, in principle, to describe a cohort’s course over time rather than relying on a single observation. In general, measurements from the same participant are related to one another; they should not automatically be treated as if each came from a different, unrelated person. An analysis of repeated measurements may need to account for that relationship when estimating trends or uncertainty.
The registry identifies the time points but does not report the statistical method used to analyze repeated measurements. It does not state whether the primary summaries were calculated separately at each time point, whether a model was fitted, or how differences in participants contributing over time were handled. Those analytical details are not reported in the registry record. The measurement schedule alone cannot establish that every participant contributed a complete series.
What does the observational design permit?
In general, an observational cohort can describe outcomes recorded in the course of routine care. When treatment is not randomly assigned, characteristics related to treatment choice or outcome can differ across participants and over time. A comparison intended to estimate a causal treatment effect must address those potential differences, and a suitable comparator is needed to define the contrast. The record lists one cohort and does not state allocation or describe a control group. It reports 0 analyses, so no adjusted comparison is available to interpret.
This does not make descriptive measurement summaries meaningless. It does mean that the summaries answer a narrower question: what was recorded among the participants represented in the analysis, rather than what effect treatment caused compared with an alternative. The numerical summaries needed to answer even that descriptive question are not reported in the registry record.
How should uncertainty be understood?
In general, a confidence interval gives a range of values compatible with the data and a specified statistical procedure. Its width reflects the precision of the estimate under that procedure. A p-value, when used, addresses compatibility of data with a specified null hypothesis and model; it does not measure clinical importance or the probability that a treatment works. The record does not report confidence intervals, p-values, or the inferential procedures that would define them.
Over-dispersion is a general concern when the observed variability is greater than a statistical model expects. If present and ignored, standard errors and tests based on that model may be unreliable. The record gives no model or variance assumptions to assess, and no numerical outcome values from which to evaluate dispersion. This is a general methodological point, not a claim that over-dispersion occurred in this study.
What does the planning illustration mean?
The planning assumptions describe a hypothetical calculation using a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. They specify detecting a stated fraction of an observed effect. These are assumptions for planning, not evidence that the study used a two-arm randomized design. The registry describes one observational cohort, and it does not report a numerical observed effect for the primary outcome.
In general, sample-size planning estimates how many participants a future design might need under stated assumptions about the effect, variability, allocation, and testing procedure. A planned sample size is not the number actually analyzed, and it is not observed power. Power is not established after the fact by substituting an observed result into a planning formula. Since no observed hemoglobin effect or numerical sample-size estimate is reported in the registry record, no such quantity can be interpreted for this study.
The stated planning convention distinguishes participants per arm for ordinary outcomes from total events for time-to-event outcomes. That distinction is methodological guidance for reading planning estimates. It does not turn this cohort into a randomized comparison, and it does not supply an outcome estimate or an analysis that the registry does not report.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists 3 outcome measures, while identifying hemoglobin levels at monthly intervals as the primary outcome. A plan for handling multiplicity across outcomes or repeated time points is not reported in the registry record. In general, evaluating many outcomes or time points can increase the chance of observing a seemingly notable result by chance if each is tested separately. Statistical approaches can address this issue, but the appropriate approach depends on the prespecified questions and analysis plan. No multiplicity adjustment or hierarchy of tests is reported.
Missing data handling is also not reported in the registry record. The planned follow-up extends to Month 24, and the primary outcome population is described as participants with at least 1 hemoglobin value after their first application. The entry’s population wording is incomplete, and it does not state how absent measurements, withdrawal, or incomplete follow-up were handled. In general, a mean calculated from available observations may describe a different set of people at different time points. If availability is related to participants’ health or other characteristics, that pattern can affect interpretation.
The enrollment count of 1083 is not a substitute for time-specific analysis counts. The registry does not report how many participants contributed to each monthly mean or standard deviation, nor does it describe imputation or another missing-data method. The record lists 0 analyses, and an inferential analysis population or statistical plan is not reported in the registry record. Therefore, the extent to which missingness and multiplicity were addressed cannot be assessed.
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 |
|---|---|---|---|
| Methoxy Polyethylene Glycol-epoetin Beta | 172 | 978 | 17.6% |
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 |
|---|---|
| Methoxy Polyethylene Glycol-epoetin Beta | 120 of 978 |
Most frequent serious adverse event terms
| Event term | Organ system | Methoxy Polyethylene Glycol-epoetin Beta |
|---|---|---|
| Death | General disorders | 21 of 978 |
| Myocardial infarction | Cardiac disorders | 11 of 978 |
| Pneumonia | Infections and infestations | 11 of 978 |
| Fall | Injury, poisoning and procedural complications | 9 of 978 |
| Cardiac failure | Cardiac disorders | 8 of 978 |
| Sudden cardiac death | General disorders | 8 of 978 |
| Sepsis | Infections and infestations | 8 of 978 |
| Atrial fibrillation | Cardiac disorders | 6 of 978 |
| General physical health deterioration | General disorders | 6 of 978 |
| Peripheral arterial occlusive disease | Vascular disorders | 6 of 978 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Methoxy Polyethylene Glycol-epoetin Beta |
|---|---|---|
| Urinary tract infection | Infections and infestations | 6 of 978 |
| Overdose | Injury, poisoning and procedural complications | 6 of 978 |
| Haemoglobin abnormal | Investigations | 6 of 978 |
| Bronchitis | Infections and infestations | 5 of 978 |
| Shunt occlusion | Injury, poisoning and procedural complications | 5 of 978 |
| Back pain | Musculoskeletal and connective tissue disorders | 5 of 978 |
| Nasopharyngitis | Infections and infestations | 4 of 978 |
| Fall | Injury, poisoning and procedural complications | 4 of 978 |
| Gout | Metabolism and nutrition disorders | 4 of 978 |
| Muscle spasms | Musculoskeletal and connective tissue disorders | 4 of 978 |
Serious events with the highest arm-level rate: death (2.1%), myocardial infarction (1.1%), pneumonia (1.1%), fall (0.9%), cardiac failure (0.8%).
The registry lists 978 participants at risk for serious adverse events, of whom 172 are recorded as affected. For other adverse events, it also lists 978 participants at risk, with 120 affected. These are separate categories in the record; they should not be added together because the registry does not state whether participants can appear in both categories. The counts indicate participants affected, not necessarily the total number of event episodes.
The most frequently listed serious-event terms and their reported percentages are Death, 2.1%; Myocardial infarction, 1.1%; Pneumonia, 1.1%; Fall, 0.9%; Cardiac failure, 0.8%; and Sudden cardiac death, 0.8%. These are registry-listed terms and percentages. They do not provide a comparison with an untreated group or another treatment, and they do not establish that MIRCERA caused an event.
The separate death count is not reported in the registry record. The percentage attached to the serious-event term Death should not be treated as a substitute for a separately reported death count, nor as evidence of causal attribution. The record also does not provide event timing, duration, severity details beyond the serious-event classification, or participant-level context. Safety figures describe events recorded in this cohort and should be interpreted within those limits.
12. What the Result Does, and Does Not, Mean
The record documents an observational investigation of long-term MIRCERA use in clinical routine and a plan to measure hemoglobin repeatedly in people with chronic kidney disease and renal anemia. It identifies a cohort, an enrollment of 1083, and a planned collection period of at least 24 months per patient. Those details explain what the study set out to observe.
The record does not report numerical hemoglobin measurements or an analysis of their pattern. It therefore cannot establish whether the cohort’s mean hemoglobin rose, fell, or remained similar over time, nor how precisely any such pattern was estimated. The absence of reported numerical results is not evidence that no change occurred. It means the change cannot be evaluated from the registry record.
The observational design also limits what can be concluded about cause. A change observed during treatment would not, by itself, demonstrate that treatment produced that change. No comparator group or random allocation is described, and the record reports 0 analyses. Other influences on measurements over time cannot be separated using an unadjusted before-and-after description alone.
For the same reasons, the completed study status and the serious adverse-event figures do not establish a treatment benefit or harm. Safety events are recorded for participants in the cohort, but there is no like-for-like control comparison or reported causal analysis. The figures can describe what was listed in the record; they cannot quantify an excess or reduction attributable to treatment.
The appropriate conclusion is bounded by the available reporting: the registry describes the intended observational question, outcome schedule, and adverse-event counts, but does not report the numerical primary outcome findings or inferential analyses. The information supports understanding the study’s scope, not a judgment about whether MIRCERA changes hemoglobin or about the cause of events recorded during follow-up.
13. Why This Trial Matters Statistically
This study is statistically useful as an example of the distinction between a treatment question and a descriptive cohort question. The title refers to long-term effects, but the registry describes an observational cohort with no stated comparator or allocation. A cohort can show what was measured during routine use; causal claims require a design and analysis that address what would have happened under an alternative course of care.
Repeated hemoglobin measurements raise practical analytical questions even when the intended summary is straightforward. The participants contributing data can vary from one time point to another, and measurements from the same person are generally related. A clear report of analysis populations, time-specific counts, methods for repeated observations, and missing-data handling would help readers understand how the summaries were formed. Those details are not reported in the registry record.
The record also illustrates why a defined endpoint is not the same as a reported result. The outcome is named, the unit and summary measures are specified, and the schedule is detailed. Yet without the actual means, standard deviations, participant counts, and uncertainty estimates, readers cannot judge the direction, magnitude, or precision of the observed course.
Finally, the safety figures show why denominators and context matter. Counts of affected participants and listed event terms describe recorded events, but they do not establish comparative risk or causation in the absence of a comparator and relevant analysis. For clinical researchers, the key statistical lesson is to distinguish descriptive evidence from comparative evidence and to make the analysis population and uncertainty visible when interpreting longitudinal observational data.
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 limitation for interpreting efficacy-related outcomes is that numerical hemoglobin results are not reported in the registry record. Means, standard deviations, time-specific participant counts, and uncertainty estimates are absent. The measurement schedule therefore describes what was intended, but not the observed trajectory or its precision.
The design is observational, with one listed cohort and no stated allocation or comparator. This limits causal interpretation and leaves no like-for-like control comparison for separating treatment-associated changes from other changes over time. The registry does not describe adjustment for confounding or other analytical methods that might address differences among participants.
The planned follow-up is at least 24 months, but actual follow-up completeness is not reported in the registry record. The endpoint population definition is truncated, and time-specific analysis populations are not given. Missing-data methods and the handling of incomplete follow-up are also not reported. These gaps prevent assessment of whether participants with available measurements differed from those without them.
The record lists 3 outcome measures and 0 analyses. A statistical analysis plan, multiplicity approach, interim analyses, and sample-size justification are not reported in the registry record. Safety information includes affected-participant counts and selected serious-event terms, but does not provide a comparator, causal attribution, event timing, or a separate death count. These reporting limitations constrain interpretation of both outcome patterns and safety figures.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Observational Study to Investigate the Long-term Effects of MIRCERA in Clinical Routine — NCT01309269.
- Registry record last updated 2016-11-02; status last verified 2016-11.
- Results first posted 2015-10-29.
- 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
NCT01309269 is a completed observational study titled “Observational Study to Investigate the Long-term Effects of MIRCERA in Clinical Routine.” The official title describes a non-interventional study of long-term MIRCERA effects in clinical routine. Hoffmann-La Roche is listed as sponsor. The registry reports a start date of 2010-09, primary completion date of 2014-04, and enrollment of 1083.
The study concerns chronic kidney disease patients with renal anemia and planned data collection for at least 24 months. Its primary outcome is mean hemoglobin in g/dL with standard deviation, measured prior to Day 1 and at monthly intervals through Month 24. The registry lists 3 outcome measures and 0 analyses. Numerical primary outcome findings, time-specific analysis counts, and a detailed statistical analysis plan are not reported in the registry record.
The adverse-event record lists 978 participants at risk for serious events and 172 affected, alongside 978 at risk for other events and 120 affected. Listed serious-event terms include Death, 2.1%; Myocardial infarction, 1.1%; Pneumonia, 1.1%; Fall, 0.9%; Cardiac failure, 0.8%; and Sudden cardiac death, 0.8%. These figures do not establish causation or comparative risk.