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 A Study Of The Analgesic (Pain-Relief) Effects Of Tanezumab In Adult Patients With Diabetic Peripheral Neuropathy (NCT01087203), a randomized phase 2 study. The primary outcome is Change From Baseline in Average Diabetic Peripheral Neuropathy (DPN) Pain Score at Week 16.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01087203 |
| Phase | Phase 2 |
| Condition | Diabetic Peripheral Neuropathy |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Double |
| Enrollment | 73 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Pfizer |
| Results posted | Yes |
2. Clinical Question
Population
Adults with painful diabetic peripheral neuropathy. The registry record lists diabetic peripheral neuropathy as the condition and describes the study as enrolling adult patients with painful symptoms. The total enrollment was 73; the number randomized or included in the primary analysis is not stated as a separate count in the registry record.
Intervention
Tanezumab, described as an investigational biological intervention. The dose and schedule are not reported in the registry record.
Comparator
Placebo. The registry record does not provide additional details about the placebo or treatment administration.
Primary question
What was the change from baseline in average diabetic peripheral neuropathy pain score at Week 16 in the randomized groups? The registry record defines how the score was assessed, but the group results and treatment comparison are not reported in the registry record.
The study was described as a Phase 2 proof-of-concept investigation of tanezumab’s analgesic effects. Its primary endpoint focused on participants’ average pain ratings rather than a clinician-rated examination or a laboratory measurement. Participants used an 11-point Numeric Rating Scale to assess diabetic peripheral neuropathy pain during the past 24 hours, with scores ranging from 0 for no pain to 10 for the worst possible pain.
The endpoint compared baseline with the Week 16 assessment. Baseline was calculated from average pain scores over the initial pain assessment period, and the Week 16 value was based on the seven days before and including Day 113. The primary question is therefore about change in a repeated patient-reported pain measure over time. Without the arm-specific endpoint estimates and their uncertainty, the registry record does not establish the size or precision of any difference between tanezumab and placebo.
3. Trial Design
The registry describes a randomized, double-blind, placebo-controlled, multicenter, parallel-group Phase 2 study. Random allocation is intended to create groups that can be compared, while double masking is intended to limit the influence of treatment knowledge on participants’ reports and study assessments. A parallel-group design assigns participants to a group and follows the groups over the study period rather than switching participants between treatments.
The trial enrolled 73 participants and is listed as terminated. The registry record gives a start date of 2010-03-30 and a primary completion date of 2010-11-18. It identifies tanezumab and placebo as the interventions. The allocation ratio, arm-specific enrollment, reasons for termination, and the dates or circumstances of the termination are not reported in the registry record. Nor does the record state the treatment dose or administration schedule.
The primary outcome was change from baseline in average diabetic peripheral neuropathy pain score at Week 16. The listed primary analysis population was the ITT analysis set, defined in the registry as randomized participants who received at least one dose of study medication. Last Observation Carried Forward was used for imputation. The number of participants included in that analysis is not reported in the registry record.
The record also lists secondary outcomes that cover pain ratings at other weeks, cumulative or threshold-based pain reductions, pain interference, neuropathic pain symptoms, and patient global assessment. The registry lists 27 outcome measures and seven analyses, but does not describe a full statistical analysis plan. Details such as the randomization procedure, allocation concealment, treatment adherence, protocol deviations, and the handling of all analysis populations 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 | Placebo | Tanezumab |
|---|---|---|
| STARTED | 35 | 38 |
| COMPLETED | 3 | 3 |
| NOT COMPLETED | 32 | 35 |
Reasons for not completing this period:
| Reason | Placebo | Tanezumab |
|---|---|---|
| Lost to Follow-up | 2 | 0 |
| Withdrawal by Subject | 2 | 6 |
| Lack of Efficacy | 1 | 2 |
| Study terminated by sponsor | 27 | 27 |
Analysis population for the primary outcome, as defined in the registry: ITT analysis set included all randomized participants who received at least 1 dose of study medication. Last Observation Carried Forward (LOCF) method of imputation was used.
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: Intent to treat (ITT) analysis set included all randomized participants who received at least 1 dose of study medication.
| Characteristic | Unit | Placebo | Tanezumab | Total |
|---|---|---|---|---|
| Participants analysed | 35 | 38 | 73 | |
| Age, Continuous | Years | 59.6 (SD 11.6) | 61.6 (SD 8.9) | 60.7 (SD 10.2) |
| Sex: Female, Male: Female | Participants | 15 | 11 | 26 |
| Sex: Female, Male: Male | Participants | 20 | 27 | 47 |
6. Primary Endpoint
The registry lists the primary outcome as Change From Baseline in Average Diabetic Peripheral Neuropathy (DPN) Pain Score at Week 16, measured over Baseline, Week 16.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Deviation |
| Unit | Units on a scale |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is change from baseline in average diabetic peripheral neuropathy pain score at Week 16. Participants rated their pain during the past 24 hours on an 11-point Numeric Rating Scale, ranging from 0 for no pain to 10 for the worst possible pain. The baseline value was calculated as the mean of average pain scores over the three days in the initial pain assessment period. The Week 16 value was the average score for the seven days before and including Day 113.
A repeated rating can capture a participant’s reported symptom level at more than one point in the study. Expressing the endpoint as change from baseline focuses on how the Week 16 score differs from the participant’s starting assessment, rather than relying only on a final score. This is a general explanation of the endpoint’s statistical purpose; the registry record does not provide the group means, the between-group estimate, or a measure of uncertainty for this outcome.
The scale assigns higher values to worse pain. However, the registry record does not report the observed change in either group, so it is not possible to describe the direction or magnitude of the posted primary results. It also does not report whether the analysis adjusted for baseline score or used any additional covariates.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record defines a patient-reported pain endpoint and identifies the planned primary analysis population and imputation method. It does not report the primary endpoint estimates for tanezumab or placebo, a between-group contrast, a confidence interval, or a p-value. Consequently, the size, direction, and precision of the primary comparison cannot be assessed from the registry record.
A mean change would describe the average movement in pain scores within a group. A between-group estimate would describe the difference between those average changes. A confidence interval, if reported, would communicate the range of values compatible with the analysis under its assumptions; its width would help convey precision. A p-value, if reported, would address compatibility with a specified null model and would not by itself describe the size or practical importance of an effect. These are general statistical interpretations, not results reported for this study.
The scale ranges from 0 for no pain to 10 for the worst possible pain, but the registry entry supplies no Week 16 means or changes. The enrollment count of 73 does not substitute for endpoint results and does not reveal how many participants contributed data to the primary analysis. The record’s analysis-set definition requires randomization and receipt of at least one dose; the count meeting that definition is not reported in the registry record.
The registry lists secondary endpoints at several time points and involving several types of pain and function measures. Those outcomes may provide different descriptions of participants’ experiences, but their results are not included in the registry information. Without outcome estimates, uncertainty measures, and information about how the many listed analyses were handled, no claim about consistency across outcomes or the robustness of a result can be made.
The trial is listed as terminated, but the reason for termination and its implications for data collection are not reported in the registry record. Termination alone does not explain whether the primary outcome was collected as planned or why results are absent. The appropriate statistical reading is limited: the registry describes a randomized comparison and its endpoint methods, while the posted information does not establish the comparative Week 16 pain outcome.
9. Statistical Methods Explained
The study’s registry description identifies a continuous primary outcome: change from baseline in average pain score. A continuous measure can take values across a numeric scale, and a group mean provides one summary of its central tendency. The record specifies standard deviation as the dispersion measure for the primary outcome, but does not report the observed means or standard deviations.
What does the mean describe?
As a general statistical concept, the mean summarizes the average value across participants with data. It can be useful for describing a group’s typical score, but it does not show every participant’s experience. Two groups can have similar means while having different distributions, and a mean can be influenced by unusually high or low observations. A standard deviation describes spread around the mean; it is not the same as the uncertainty in the estimated mean or in a between-group contrast.
The primary scale is an 11-point Numeric Rating Scale from 0 for no pain to 10 for the worst possible pain. The registry defines the baseline score using the mean of average pain scores over three days in the initial pain assessment period. The Week 16 score is based on the seven days before and including Day 113. Repeated assessments can reduce reliance on a single day’s report, although the registry does not provide evidence about completion rates or the variability of these assessments.
How should change from baseline be read?
In general, change from baseline compares a later measurement with a starting measurement. This can help describe whether scores move over time and can support a comparison between randomized groups. Interpreting the direction requires knowing the score’s meaning: on this scale, higher values represent worse pain. Still, without the reported changes and the analysis’s sign convention, the registry record does not support a statement about the observed direction or size of change.
A comparative estimate is more informative than separate within-group changes for evaluating a randomized comparison. A change in one group alone does not identify how that group would have changed under the other assignment. Randomization is intended to support a fair comparison between assigned groups, while masking can limit some influences on reporting or assessment. These are general design principles; the registry’s description does not establish how well the groups remained comparable or whether masking was maintained.
What does imputation mean in this record?
The registry says Last Observation Carried Forward was used. As a general method, this approach fills a missing later measurement using a participant’s last observed measurement. It makes an analysis possible for records with missing follow-up values, but it relies on assumptions about what would have happened after the last observation. It can fail to reflect actual later outcomes when symptoms change over time. The registry record does not report how many values were imputed, why observations were missing, or whether alternative missing-data analyses were conducted.
The primary analysis population is defined as all randomized participants who received at least one dose of study medication. The number in this set is not reported in the registry record. The record does not explain whether participants who were randomized but did not receive a dose were included in another analysis, or how protocol deviations were treated.
What can uncertainty measures contribute?
Generally, a confidence interval communicates uncertainty around an estimated quantity. A narrower interval indicates greater precision under the analysis assumptions, while a wider interval indicates more uncertainty. A p-value evaluates how compatible the data are with a specified null hypothesis under a statistical model; it does not measure the probability that a treatment effect is real, nor does it convey the magnitude of an effect. Neither a confidence interval nor a p-value for the primary comparison is reported in the registry record, so these concepts cannot be applied to quantify this study’s result.
The registry’s planning description refers to an illustrative sample-size calculation using a two-sided significance level of 0.05, equal allocation, and a normal approximation, with the detectable effect expressed as a fraction of the observed effect. It specifies participants per arm for non-time-to-event outcomes. These calculations are planning illustrations based on the observed effect, not the trial’s own design justification and not observed power. The record does not report the original sample-size justification, and no numerical planning outputs are stated in the registry information.
More broadly, a complete interpretation would require the actual group estimates, a clearly defined comparison, uncertainty measures, analysis details, and information about missing observations. Those statistical results and details are not reported in the registry record. General methods can explain what such quantities would mean, but cannot replace the missing results.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists multiple secondary outcomes, including pain-score changes at several weeks, cumulative reductions, threshold-based reductions, pain interference, neuropathic pain symptoms, and patient global assessments. It records 27 outcome measures and seven analyses. When many outcomes, time points, or analyses are examined, the chance of finding an apparently notable result by chance can increase. This is the general statistical issue of multiplicity.
The registry record does not report whether the study used a prespecified hierarchy, adjusted significance thresholds, or another method to address multiplicity. The statistical analysis plan is not reported in the registry record. Therefore, the results of multiple outcomes, if available elsewhere, could not be interpreted as confirmatory or exploratory based on the registry information alone.
For the primary outcome, the registry states that Last Observation Carried Forward was used. This is an imputation method for missing follow-up values, and the general limitation is that a participant’s last observed value may not represent their later value. The number and reasons for missing assessments, the extent of imputation, and sensitivity analyses are not reported in the registry record. Several secondary outcomes also explicitly mention LOCF, but the registry does not describe missing-data handling for every listed outcome.
The primary analysis population is defined as randomized participants who received at least one dose of study medication. The registry does not state the number included in this analysis or report how other analysis populations were defined. It also does not report the number excluded from any analysis or the reasons for exclusion. As a result, the effects of missing data, analysis-set membership, and multiplicity on the study’s statistical conclusions cannot be evaluated from 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 |
|---|---|---|---|
| Placebo | 0 | 35 | 0.0% |
| Tanezumab | 1 | 38 | 2.6% |
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 |
|---|---|
| Placebo | 19 of 35 |
| Tanezumab | 24 of 38 |
Most frequent serious adverse event terms
| Event term | Organ system | Placebo | Tanezumab |
|---|---|---|---|
| Carotid Artery Stenosis | Cardiac disorders | 0 of 35 | 1 of 38 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Placebo | Tanezumab |
|---|---|---|---|
| Arthralgia | Musculoskeletal and connective tissue disorders | 2 of 35 | 7 of 38 |
| Back pain | Musculoskeletal and connective tissue disorders | 3 of 35 | 3 of 38 |
| Pain in extremity | Musculoskeletal and connective tissue disorders | 1 of 35 | 4 of 38 |
| Post procedural haemorrhage | Injury, poisoning and procedural complications | 2 of 35 | 1 of 38 |
| Myalgia | Musculoskeletal and connective tissue disorders | 0 of 35 | 3 of 38 |
| Burning sensation | Nervous system disorders | 1 of 35 | 2 of 38 |
| Abdominal distension | Gastrointestinal disorders | 2 of 35 | 0 of 38 |
| Fatigue | General disorders | 1 of 35 | 1 of 38 |
| Oedema peripheral | General disorders | 0 of 35 | 2 of 38 |
| Urinary tract infection | Infections and infestations | 1 of 35 | 1 of 38 |
Serious events with the highest arm-level rate: carotid artery stenosis (2.6%).
The registry reports serious adverse events in the placebo group as 0 of 35 participants at risk and in the tanezumab group as 1 of 38 participants at risk. It reports other adverse events in the placebo group as 19 of 35 and in the tanezumab group as 24 of 38. These are participant counts within the groups identified in the registry; they are not primary pain-outcome results.
The registry also lists carotid artery stenosis at 2.6% among the top serious adverse event terms. The record does not clarify the group attribution of that term in the information. Deaths are not reported in the registry record.
Adverse-event counts describe what was recorded, but they do not by themselves establish that an event was caused by a study intervention. The registry information does not give event-level timing, severity beyond the serious classification, duration, relatedness assessment, or a statistical comparison. The number of participants at risk is shown for each group, but these counts should not be read as a complete account of safety without the study’s definitions and broader clinical context. No treatment recommendation follows from these figures.
12. What the Result Does, and Does Not, Mean
The registry record documents a randomized, double-blind, placebo-controlled Phase 2 study of tanezumab in adults with painful diabetic peripheral neuropathy. It identifies a patient-reported primary endpoint: change from baseline in average pain score at Week 16. It also describes the scale, assessment periods, analysis population, and use of Last Observation Carried Forward.
What the record does not report is central to interpreting the clinical comparison. The primary endpoint values by group, the between-group estimate, uncertainty measures, and p-value are not reported in the registry record. Therefore, the record does not show the magnitude or precision of the Week 16 difference, or whether the groups’ reported pain scores changed in a particular direction. It cannot establish whether there was a meaningful difference between groups.
The registry lists secondary measures and some adverse-event counts, but those details cannot substitute for the missing primary endpoint results. The safety counts are descriptive and do not by themselves establish cause or provide a complete safety assessment. The reason for trial termination, the number analyzed for the primary outcome, and the missing-data pattern are also not reported in the registry record.
In general, a randomized design can support a comparative interpretation when the results and analysis details are available and the design is carried out as intended. The design label alone does not supply the treatment estimate or resolve concerns about missing data, multiplicity, or analysis populations. The registry record therefore supports a description of the study question and methods, but not a conclusion about the comparative effect of tanezumab on pain at Week 16.
13. Why This Trial Matters Statistically
This trial is statistically notable as a randomized, double-blind, parallel-group comparison using a patient-reported continuous pain measure. That design makes the intended comparison clear: assess change in average diabetic peripheral neuropathy pain from baseline to Week 16 between participants assigned to tanezumab and those assigned to placebo. The endpoint definition also specifies how baseline and follow-up values were constructed, which is important for understanding what an estimate would represent.
The registry record illustrates why design information and outcome results are distinct. Knowing that a study was randomized and masked does not reveal the estimated difference, its uncertainty, or the completeness of the endpoint data. The record gives an enrollment total and a primary analysis definition, but not the number contributing to that analysis or the primary estimates. Without those quantities, statistical precision and the strength of evidence cannot be assessed.
The endpoint also raises general issues relevant to pain trials: repeated self-reports are measurements of participants’ experiences, while summary means describe group averages rather than every participant’s response. The use of LOCF is another interpretive consideration because imputing missing follow-up values depends on assumptions. The registry does not report enough information to assess the amount of missing data or the effect of alternative assumptions.
Finally, the registry lists many outcomes and analyses but does not report a multiplicity strategy. This makes clear why prespecified analysis plans and transparent reporting are important when interpreting a broad set of outcomes. The study’s value as a statistical record lies in the methods and questions it documents; the absent primary results limit what can be concluded from the registry entry.
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 interpretation is that the registry record does not report the primary endpoint results. There are no group-specific Week 16 changes, between-group estimate, confidence interval, or p-value in the registry information. Consequently, the direction, magnitude, and precision of the principal comparison cannot be characterized.
Although total enrollment is stated as 73, arm-specific enrollment for the efficacy analysis is not reported in the registry record. The record defines the primary analysis set as randomized participants who received at least one dose, but gives no count for that set. It does not report the amount or pattern of missing primary endpoint data, the number of observations imputed with LOCF, or sensitivity analyses addressing the imputation assumptions.
The study is listed as terminated, but the reason and consequences for follow-up or analysis are not reported in the registry record. The registry also does not provide the dose or schedule, randomization details, treatment adherence, protocol deviations, or the full statistical analysis plan. Its list of outcomes and analyses raises a general multiplicity concern, but the method used to address it is not reported.
Safety information is limited to participant counts and a listed serious-event term. The registry does not give the context needed to assess timing, relatedness, or a comparative safety analysis, and deaths are not reported in the registry record. These limitations describe gaps in the registry information; they do not establish why the information is absent or what the unreported trial results were.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: A Study Of The Analgesic (Pain-Relief) Effects Of Tanezumab In Adult Patients With Diabetic Peripheral Neuropathy — NCT01087203.
- Registry record last updated 2021-02-24; status last verified 2021-02.
- Results first posted 2021-02-24.
- 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
NCT01087203 is a Phase 2 randomized, double-blind, placebo-controlled, multicenter, parallel-group study of tanezumab in adults with painful diabetic peripheral neuropathy. The record lists enrollment of 73 and a terminated status. Its primary outcome is change from baseline in average pain score at Week 16, assessed using an 11-point Numeric Rating Scale. The primary analysis population is defined as randomized participants who received at least one dose, with LOCF imputation.
The registry record does not report the primary endpoint results, the reason for termination, the number included in the primary analysis, or the statistical analysis plan. It lists serious adverse events as 0 of 35 for placebo and 1 of 38 for tanezumab, and other adverse events as 19 of 35 and 24 of 38, respectively. These safety counts do not provide the missing comparative pain results.