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 Long-Term Safety Study Of Inhaled Insulin (CP-464,005, Inhaler) In Japanese Patients With Type1 or Type2 Diabetes (NCT00527397), a non-randomized phase 3 study. The primary outcome is Self-Monitoring Blood Glucose Levels: Change From Baseline.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00527397 |
| Phase | Phase 3 |
| Condition | Diabetes Mellitus, Type 2, Diabetes Mellitus, Type 1 |
| Allocation | Non-Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 24 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Pfizer |
| Results posted | Yes |
2. Clinical Question
Population
Japanese patients with type 1 or type 2 diabetes. The brief description specifies non-smokers; further eligibility details are not reported in the registry record.
Intervention
CP-464,005, an inhaled insulin administered using an inhaler. The study description sets out a planned one-year (52 week) administration period.
Comparator
There was no control group. The study was open-label and uncontrolled, and its groups were not a like-for-like control comparison.
Primary question
How did self-monitoring blood glucose change from baseline over one year? The endpoint was not analyzed because early termination left small numbers of subjects.
The central question in the registry record concerns change in self-monitored blood glucose during treatment with inhaled insulin. The primary endpoint was defined as the values obtained at each observation point minus the value at baseline. It was specified as a continuous measure, with the mean and standard deviation as the planned summary, and milligram/millilitre as the unit.
The study description also names safety and toleration as aims. It lists patients with type 1 diabetes separately from patients with type 2 diabetes who had not yet been treated with insulin and patients with type 2 diabetes who had already been treated with insulin. These are different clinical groups, not randomized treatment arms intended to provide a controlled comparison.
The record says that the primary endpoint was not analyzed because early termination resulted in small numbers of subjects. It therefore does not provide a primary endpoint estimate describing change in self-monitoring blood glucose. Nor does the registry record report a comparator-based estimate of treatment effect. The question can be described from the registered objective, but the posted results do not answer it with an analyzed glucose outcome.
3. Trial Design
This was a phase 3, open-label, uncontrolled, non-randomized study with a parallel-group structure. Pfizer is identified as the sponsor. The study began in 2007-08, had a primary completion date of 2008-07, enrolled 24 participants, and is listed as terminated. The planned administration period in the brief description was one year (52 week).
The three group descriptions distinguish type 1 diabetes, type 2 diabetes without prior insulin treatment, and type 2 diabetes with prior insulin treatment. The registry labels these groups A, B, and C, respectively. They represent clinical categories rather than a randomized comparison of inhaled insulin against a control treatment. The record does not report the number enrolled in each group or explain how participants were assigned to them.
The study was open-label, meaning masking was not used. No placebo or active control group is described. Consequently, the design can describe observations during treatment but does not supply a concurrent control for separating treatment-associated changes from other changes over time. Differences between the clinical groups also cannot be interpreted as randomized treatment effects.
The registered primary outcome was change from baseline in self-monitoring blood glucose at one year. The record lists nine outcome measures in total, including daily inhaled insulin dose, changes in hemoglobin A1c and fasting plasma glucose, hypoglycaemia, lung-function measures, and insulin antibody levels. The record reports no analysis entries. It specifically states that the primary endpoint was not analyzed because the study ended early and the subject numbers were small. The reason for termination beyond that endpoint statement, and details of any other conduct changes, 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: As a result of Pfizer's decision (18 Oct 2007) to return the worldwide rights for CP-464,005 (insulin human \[rDNA origin\] Inhalation Powder) to Nektar, from which Pfizer licensed inhaled insulin technology, it was decided to terminate this study before it had recruited targeted number of subjects.
Overall Study
| Stage | All Subjects With Type 1 or Type 2 Diabetes Mellitus |
|---|---|
| STARTED | 24 |
| COMPLETED | 0 |
| NOT COMPLETED | 24 |
Reasons for not completing this period:
| Reason | All Subjects With Type 1 or Type 2 Diabetes Mellitus |
|---|---|
| Adverse Event | 3 |
| Lack of Efficacy | 1 |
| Protocol Violation | 1 |
| Withdrawal by Subject | 6 |
| Study terminated by sponsor | 13 |
Analysis population for the primary outcome, as defined in the registry: This endopoint was not analyzed because of small numbers of subjects due to early termination
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 | All Subjects With Type 1 or Type 2 Diabetes Mellitus |
|---|---|---|
| Participants analysed | 24 | |
| Age Continuous | years | 55.2 (SD 15.0) |
| Sex: Female, Male: Female | Participants | 13 |
| Sex: Female, Male: Male | Participants | 11 |
6. Primary Endpoint
The registry lists the primary outcome as Self-Monitoring Blood Glucose Levels: Change From Baseline, measured over One year.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Deviation |
| Unit | milligram/millilitre |
| Endpoint classification | Continuous Endpoint |
The primary endpoint was change from baseline in self-monitoring blood glucose levels over one year. The description defines each change as the value recorded at an observation point minus the baseline value. The registry specifies a mean as the measure of central tendency, a standard deviation as the measure of dispersion, and milligram/millilitre as the unit. It does not provide a numerical result for this endpoint.
As general background, self-monitoring blood glucose records glucose measurements made by participants during daily management. Looking at change from baseline can describe how a measure varies over the course of a study relative to each participant’s starting value. A mean summarizes the average change across participants, while a standard deviation describes how dispersed individual changes are around that mean. Neither summary alone establishes that treatment caused a change.
In an uncontrolled study, a change from baseline does not distinguish a treatment-associated change from changes that could occur over time for other reasons. A controlled comparison can help address that question, but no control group is described in this record. In addition, the primary endpoint was not analyzed because early termination left small numbers of subjects. Thus, the registry record specifies what was intended to be measured and how the outcome was defined, but it does not report an estimate of the mean change or its variability.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The main interpretive fact is that the planned primary endpoint has no reported analysis. The registry states that change in self-monitoring blood glucose was not analyzed because the study terminated early and the number of subjects was small. No mean change, standard deviation, confidence interval, or test result for that endpoint is reported in the registry record. There is therefore no posted primary-outcome estimate with which to describe the size or precision of change over one year.
The study was uncontrolled and non-randomized. Even if a before-and-after glucose estimate had been reported, it would describe change in the enrolled group rather than isolate the effect of CP-464,005 from other influences. The three groups were defined by diabetes type and prior insulin treatment; the record does not describe them as comparable control groups. Their observations cannot be treated as a randomized contrast.
The record does include adverse-event information. For the group titled all subjects with type 1 or type 2 diabetes mellitus, it lists 3 subjects affected by serious adverse events and 23 affected by other adverse events. The at-risk denominators are not reported in the registry record. The listed top serious terms are tendon rupture, diabetic ketoacidosis, and hyperglycaemia, each with a reported value of 4.2%. These entries describe what is recorded, but the denominator information needed to interpret them as rates is not available in the record.
The registry also lists secondary outcomes such as daily inhaled insulin dose, changes in hemoglobin A1c and fasting plasma glucose, hypoglycaemia, lung-function measures, and insulin antibody levels. It does not report outcome analyses for these measures. Their inclusion as planned outcomes is not itself evidence of a particular result.
The record lists 0 analysis entries. This means that the registry does not provide an analyzed primary outcome or a set of inferential results from which to assess effect size and statistical precision. The available information supports a description of the design, planned measurements, early termination, and adverse-event entries. It does not support a conclusion about the magnitude of glucose change or a controlled estimate of treatment effect.
9. Statistical Methods Explained
What does a change-from-baseline endpoint represent?
The primary endpoint is a continuous measure: self-monitoring blood glucose change from baseline. As a general statistical concept, a change score expresses how an observation differs from a participant’s starting value. Summarizing such scores with a mean gives the average change in the analyzed group. A standard deviation describes the spread of those individual changes. The registry defines the endpoint as the value at each observation point minus baseline and specifies a one-year timeframe.
A mean and standard deviation are descriptive summaries, not a complete account of uncertainty about the mean. A confidence interval, when reported, gives a range of values compatible with the data and the assumptions of the method used. The registry record does not report a confidence interval or the primary endpoint’s mean or standard deviation. No inferential result for this outcome can therefore be interpreted from the posted record.
Why does the study design matter?
As general background, an uncontrolled before-and-after study describes observations in participants over time but lacks a concurrent control group. A change during follow-up may reflect treatment, but it may also reflect other influences, including changes that occur naturally over time or differences in measurement conditions. A randomized control comparison can address some of these concerns by comparing groups assigned through a random process. This study was non-randomized and uncontrolled, so it does not provide that type of comparison.
The parallel groups were described by diabetes type and prior insulin treatment. Since they are different clinical categories and were not randomized control arms, a difference between them would not by itself identify a treatment effect. The registry record does not report group-specific enrollment numbers or an adjusted comparison between groups. The endpoint was not analyzed, so no such comparison is available in any case.
What can be said about precision and power?
In general, statistical precision concerns how narrowly a study estimates an outcome or effect. Small analyzed groups commonly yield less precise estimates than larger groups, but the record gives no analyzed sample sizes for the primary endpoint and no estimate of its uncertainty. The stated reason for not analyzing that endpoint was early termination and small subject numbers. No observed power calculation or trial-specific sample-size justification is reported in the registry record.
The planning illustration associated with the posted results is not the trial’s own design calculation. Its stated assumptions are a two-sided significance level of 0.05, equal allocation between two arms, a normal approximation, and an effect defined as a stated fraction of the observed effect. Such planning illustrations describe hypothetical sample-size requirements under assumptions; they are not the number of participants actually analyzed and are never observed power. They also do not replace a missing primary endpoint result.
How should repeated measurements be understood?
The endpoint description refers to values obtained at each observation point and compares them with baseline. As a general statistical issue, measurements from the same participant over time are related rather than independent. An analysis of repeated observations may need to account for that dependence, particularly if it seeks to use multiple follow-up measurements together. The registry record does not report the exact observation schedule, the model or method intended for repeated measurements, or whether any particular follow-up point would have been emphasized. It also reports that the primary endpoint was not analyzed, so no repeated-measures method or estimate can be assessed.
What do the adverse-event entries quantify?
The adverse-event record lists affected subjects and serious-event terms, but at-risk denominators are null. As a general principle, counts and percentages should be interpreted in relation to the number of people observed and the period of observation. Without reported denominators and further analysis details, the listed entries cannot establish comparative rates or quantify relative risk. The percentages attached to the top serious terms should be read as the registry’s reported values, not as a substitute for missing denominator and analysis information.
Overall, the statistical record is primarily descriptive: it identifies a continuous endpoint, its planned summary measures and timeframe, the study structure, and some adverse-event entries. The absence of an analyzed primary outcome means there is no reported estimate to evaluate for statistical significance or precision. The methods actually used for outcome analyses, if any, are not reported in the registry record.
10. Multiplicity, Missing Data and Analysis Populations
The record lists nine outcome measures, including the primary self-monitoring blood glucose endpoint and secondary measures involving insulin dose, glycaemic measures, hypoglycaemia, lung function, and insulin antibodies. When a study evaluates multiple outcomes or multiple time points, the chance of at least one apparently notable result can increase. As general background, statistical plans may address this multiplicity through a prespecified hierarchy or adjustment procedure. The registry record does not report a multiplicity strategy, a hierarchy among secondary outcomes, or any adjusted analyses.
The primary endpoint was not analyzed because the study terminated early and subject numbers were small. The record lists 0 analysis entries and provides no primary endpoint estimate. It does not report whether any secondary outcomes were analyzed, or how multiple measurements, if collected, were handled.
Missing-data procedures and analysis populations are not reported in the registry record. The record does not describe how participants with incomplete follow-up or missing measurements would be handled, whether all enrolled participants were intended for each analysis, or how discontinuations were incorporated into outcome summaries. It also does not provide participant counts by group or endpoint for analysis. These omissions limit assessment of who contributed to any result and whether missing observations could affect interpretation. They do not justify assuming a particular imputation method, analysis population, or missingness pattern.
Early termination is explicitly linked to the lack of analysis for the primary endpoint, but the registry does not provide further detail about the decision, the timing of individual withdrawals, or any planned interim analysis. Those details are not reported in the registry record.
11. What the Result Does, and Does Not, Mean
The record documents a phase 3 study of inhaled CP-464,005 in Japanese patients with type 1 or type 2 diabetes, with a planned one-year administration period. It identifies an intended primary measure, self-monitoring blood glucose change from baseline, and reports that this endpoint was not analyzed because early termination left small numbers of subjects. This is the central limit on what can be concluded from the posted outcome information.
The record does not show whether the primary glucose measure increased, decreased, or remained similar to baseline. It does not report an estimate or uncertainty interval for that endpoint, and it does not provide a controlled comparison. The planned endpoint and the list of secondary outcomes should not be mistaken for findings. The posted adverse-event entries are descriptive and lack at-risk denominators, so they do not provide a complete basis for comparing event frequency or risk.
As general statistical context, a study can have a clearly specified endpoint without producing an analyzable result for it. Likewise, an observed change in an uncontrolled study, if one were reported, would not by itself establish that the intervention caused the change. In this record, the absence of an analyzed primary outcome precludes even that descriptive comparison of baseline and follow-up values.
Accordingly, the information supports statements about the study’s design, groups, planned measurements, termination status, and recorded adverse-event entries. It does not establish the size or direction of the primary outcome, its statistical precision, or a treatment effect relative to a control. It also does not establish a complete safety profile from the adverse-event entries alone. Those questions remain unanswered in the registry record.
12. Why This Trial Matters Statistically
This trial is statistically instructive because its planned primary endpoint is clearly defined, yet the registry says it was not analyzed after early termination and small subject numbers. A protocol question and a reported result are not the same thing: specifying a measure, unit, summary statistic, and timeframe does not produce an estimate when the outcome is not analyzed.
The design also illustrates why the comparison structure matters. The study was non-randomized and uncontrolled, and its groups represented distinct diabetes and prior-treatment categories. These groups do not provide a like-for-like control comparison. Even a complete set of before-and-after measurements would have supported a description of change during the study, not a randomized estimate separating treatment effects from other influences.
The adverse-event entries offer a separate lesson about denominators. The record lists affected subjects and percentages for serious-event terms, but does not report at-risk denominators. Counts and percentages can be informative only in the context of who was observed and over what period; missing denominator information limits interpretation and prevents a sound comparative rate assessment.
Finally, the record lists multiple outcomes but does not describe multiplicity handling, missing-data methods, or analysis populations. These details matter when readers assess how results were selected, who contributed data, and how uncertainty was quantified. The registry does not establish that a particular method was used. The case therefore shows the value of distinguishing registered intentions from reported analyses and of keeping design limitations separate from outcome claims.
13. 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 is explicit: the primary endpoint was not analyzed because the study ended early and the number of subjects was small. No numerical result for change in self-monitoring blood glucose is available in the registry record. As a result, the stated primary question cannot be evaluated from the posted outcome data.
The study was open-label, non-randomized, and uncontrolled. There was no concurrent control group, and the three groups were defined by diabetes type and prior insulin treatment. These features limit causal interpretation and do not allow a like-for-like comparison between groups. Group-specific enrollment and analysis counts are not reported in the registry record.
The registry lists 24 enrolled participants overall but does not report how many contributed to each outcome or how many completed the planned follow-up. It does not describe missing-data handling, the analysis populations, or the statistical methods used for outcome analysis. It also does not report a sample-size justification for the trial or a multiplicity plan for the several listed outcomes.
For adverse events, the record lists 3 subjects affected by serious events and 23 by other events, but at-risk denominators are not reported. The three top serious terms each carry a reported value of 4.2%, yet the record does not provide information needed to assess these entries as comparative rates. The reason for termination beyond the stated effect on primary endpoint analysis, and details of any interim review, are not reported in the registry record.
14. Related Tutorials
15. Related Statistical Calculators
16. Sources
- ClinicalTrials.gov: Long-Term Safety Study Of Inhaled Insulin (CP-464,005, Inhaler) In Japanese Patients With Type1 or Type2 Diabetes — NCT00527397.
- Registry record last updated 2009-10-15; status last verified 2009-07.
- Results first posted 2009-10-05.
- 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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17. Record Summary
NCT00527397 is a phase 3, open-label, uncontrolled, non-randomized study sponsored by Pfizer. It enrolled 24 participants and is listed as terminated. The study began in 2007-08, with primary completion in 2008-07. Its stated population was Japanese patients with type 1 or type 2 diabetes; the brief description specifies non-smokers.
The intervention was CP-464,005 inhaled using an inhaler, with a planned one-year (52 week) administration period. Group descriptions distinguished type 1 diabetes, type 2 diabetes without prior insulin treatment, and type 2 diabetes with prior insulin treatment. The primary endpoint was change from baseline in self-monitoring blood glucose at one year. The registry states that it was not analyzed because early termination left small numbers of subjects. The record lists nine outcome measures and 0 analysis entries. Adverse-event entries include 3 subjects with serious events and 23 with other events; at-risk denominators are not reported.