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 Study to Evaluate the Efficacy and Safety of Lenalidomide in the Treatment of Complex Regional Pain Syndrome Type 1 (NCT00109772), a randomized phase 2 study. The primary outcome is Percentage of Participants Who Have a >= 30% Reduction (Improvement) in the Complex Regional Pain Syndrome (CRPS) Pain Intensity Numeric Rating Scale (PI-NRS) Score From Baseline to the Last Assessment.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00109772 |
| Phase | Phase 2 |
| Condition | Complex Regional Pain Syndrome, Type I |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Quadruple |
| Enrollment | 184 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Celgene Corporation |
| Results posted | Yes |
2. Clinical Question
Population
Adults with complex regional pain syndrome type 1 (CRPS type 1) were the intended study population. The registry describes an intent-to-treat population for the primary endpoint and records enrollment of 184 participants. The posted endpoint definition classifies participants who did not complete 12 weeks of treatment as non-responders.
Intervention
The double-blind treatment was oral lenalidomide at 10 mg/day for up to 12 weeks. Participants who completed double-blind treatment could continue on lenalidomide in an open-label extension for as long as benefit was derived from the drug or until study closure.
Comparator
The comparator was oral placebo for up to 12 weeks during the double-blind period. Participants who completed that period could cross over to lenalidomide 10mg in the open-label extension, for as long as benefit was derived from the drug or until study closure.
Primary question
The primary endpoint asks what percentage of participants had at least a 30% improvement in CRPS pain intensity from baseline to the last assessment. The registry defines response using the week 12 PI-NRS score and requires completion of 12 weeks of treatment; participants who did not complete treatment are counted as non-responders. Arm-level results for this endpoint are not reported in the registry record.
Statistically, the question is framed as a comparison of the proportion meeting a binary responder definition in the lenalidomide and placebo groups. That kind of endpoint turns each participant’s diary-based pain rating into a yes-or-no classification for the analysis. It does not retain the full amount of change for every participant in the primary result. The registry describes a randomized, parallel-group trial, but the primary outcome results needed to assess the between-group difference are not reported in the registry record. Consequently, the direction, size, and precision of any treatment contrast cannot be described from the posted results.
3. Trial Design
The record describes a Phase 2, multicenter, randomized, quadruple-masked, parallel-group study comparing lenalidomide with placebo. Enrollment was 184. The stated study purpose was to evaluate efficacy and safety in adults with CRPS type 1. The listed sponsor is Celgene Corporation. The study began in 2005-02, primary completion was in 2008-04, and its status is TERMINATED. The reason for termination is not reported in the registry record.
During the double-blind period, participants assigned to lenalidomide received 10 mg/day orally for up to 12 weeks; participants assigned to placebo received oral placebo for up to 12 weeks. The arm descriptions also state that participants completing double-blind treatment could enter an open-label extension. In that period, the lenalidomide arm could continue lenalidomide, while the placebo arm could cross over to lenalidomide 10mg. The extension could continue for as long as benefit was derived from the drug or until study closure. The registry entries do not give the number who entered or completed the extension, nor do they specify the timing of study closure.
Randomization is intended to create groups that can be compared without assigning treatment according to participants’ characteristics. Masking is intended to limit the influence of treatment knowledge on participant reports, clinical assessments, or study conduct. Those are general design purposes; the registry record does not identify which four roles were masked or describe how the randomization sequence was generated or concealed. The parallel model means the principal double-blind comparison assigned participants to a treatment group rather than describing a crossover during the primary treatment period. The later open-label extension is a separate feature and should not be mistaken for the randomized placebo-controlled comparison.
Although enrollment is recorded as 184, the primary endpoint description does not give the number analyzed in each randomized group or the number completing treatment. Those details, along with the reason for termination, are not reported in the registry record. The record lists 17 outcome measures and 1 analysis, but does not identify a detailed statistical analysis plan.
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: A total of 184 participants were randomized to the study and 180 participants received at least 1 dose of study drug.
Double-blind Treatment
| Stage | Lenalidomide | Placebo to Lenalidomide |
|---|---|---|
| STARTED | 90 | 94 |
| Safety and ITT Population | 87 | 93 |
| COMPLETED | 68 | 79 |
| NOT COMPLETED | 22 | 15 |
Reasons for not completing this period:
| Reason | Lenalidomide | Placebo to Lenalidomide |
|---|---|---|
| Adverse Event | 14 | 5 |
| Lack of Efficacy | 1 | 0 |
| Withdrawal by Subject | 2 | 1 |
| Lost to Follow-up | 2 | 3 |
| Protocol Violation | 0 | 1 |
| Other | 0 | 4 |
| Withdrew prior to treatment | 3 | 1 |
Open-label Extension
| Stage | Lenalidomide | Placebo to Lenalidomide |
|---|---|---|
| STARTED | 64 | 78 |
| COMPLETED | 19 | 29 |
| NOT COMPLETED | 45 | 49 |
Reasons for not completing this period:
| Reason | Lenalidomide | Placebo to Lenalidomide |
|---|---|---|
| Adverse Event | 10 | 19 |
| Lack of Efficacy | 19 | 11 |
| Withdrawal by Subject | 9 | 6 |
| Lost to Follow-up | 1 | 0 |
| Death | 0 | 1 |
| Protocol Violation | 2 | 2 |
| Other | 4 | 10 |
Analysis population for the primary outcome, as defined in the registry: Intent to treat
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 population
| Characteristic | Unit | Lenalidomide | Placebo to Lenalidomide | Total |
|---|---|---|---|---|
| Participants analysed | 87 | 93 | 180 | |
| Age Continuous | years | 43.9 (SD 11.37) | 45.1 (SD 11.06) | 44.5 (SD 11.20) |
| Sex: Female, Male: Female | Participants | 65 | 79 | 144 |
| Sex: Female, Male: Male | Participants | 22 | 14 | 36 |
| Race/Ethnicity, Customized: White | participants | 81 | 86 | 167 |
| Race/Ethnicity, Customized: Black | participants | 3 | 4 | 7 |
| Race/Ethnicity, Customized: Hispanic | participants | 1 | 3 | 4 |
| Race/Ethnicity, Customized: Asian/Pacific Islander | participants | 2 | 0 | 2 |
6. Primary Endpoint
The registry lists the primary outcome as Percentage of Participants Who Have a >= 30% Reduction (Improvement) in the Complex Regional Pain Syndrome (CRPS) Pain Intensity Numeric Rating Scale (PI-NRS) Score From Baseline to the Last Assessment, measured over Day 0, Week 12.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | percentage of participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint is the percentage of participants classified as having at least a 30% reduction, described as improvement, in the CRPS Pain Intensity Numeric Rating Scale (PI-NRS) score from baseline to the last assessment. The endpoint description says participants rated pain in the CRPS-affected limb twice each day in a diary. The PI-NRS ranges from 0=no pain to 10=worst pain imaginable. The response definition is tied to the week 12 PI-NRS score and completion of 12 weeks of treatment; a participant who did not complete 12 weeks is classified as a non-responder.
This is a binary endpoint: each participant either meets the response threshold or does not. Expressing the result as a percentage describes how common that defined response was in a group. A threshold can make a result easier to interpret than a change score alone, but it also discards information about how far each person’s change was from the cutoff. Participants just below and just above the threshold are assigned different classifications, while larger and smaller improvements among responders are not distinguished by the binary outcome.
As a general statistical concept, a responder endpoint is useful when a clinically interpretable threshold has been prespecified. The registry record does not report why the 30% threshold was selected or whether it was prespecified in the protocol. It also does not report the observed response percentages by group, the between-group estimate, or a confidence interval. Thus the endpoint definition is available, but the comparative result and its precision cannot be evaluated from the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record specifies how the primary response was defined, but it does not report the response percentage for lenalidomide or placebo. It also does not give a between-group effect estimate, a confidence interval, or a p-value for that endpoint. There is therefore no posted primary outcome result on which to base a statistical interpretation of the randomized comparison. The record’s status of TERMINATED does not, by itself, indicate the direction or size of an outcome, and the reason for termination is not reported in the registry record.
For a binary endpoint, the central descriptive quantities would ordinarily be the number and percentage of participants meeting the responder definition in each group. A comparative analysis would then quantify how those proportions differ or relate, using an estimate and a measure of uncertainty. These are general statistical descriptions, not results reported for this trial. No such group-specific primary outcome quantities appear in the registry entries. Enrollment of 184 is not a substitute for outcome data and does not establish how many participants contributed information to the endpoint.
The definition makes treatment completion part of the response classification: participants who did not complete 12 weeks are non-responders. That rule affects interpretation because the endpoint combines the pain-score threshold with completion of the treatment period. It is not simply a comparison of pain scores among participants who reached week 12. The registry does not give the number of non-completers in each arm or describe other handling of missing diary assessments, so the influence of missing or incomplete data cannot be assessed.
The primary outcome is described as percentage of participants, and the recorded population is intent to treat. The record does not explain the exact analysis set, how intent to treat was operationalized, or whether all randomized participants were included. The single recorded analysis does not identify the test, model, adjustment variables, or confidence-interval method. It would be inappropriate to infer these details from the randomized design alone.
Accordingly, the posted record supports a description of the study question and outcome definition, not a conclusion about comparative efficacy. The registry entries also do not provide results for the listed secondary outcomes. Without estimates and uncertainty measures, neither the magnitude nor the precision of any treatment-group difference can be assessed. This absence should not be converted into a finding of no difference; it means the registry record does not report the necessary outcome results.
9. Statistical Methods Explained
The primary endpoint is binary because it places participants into responder and non-responder categories. The registry defines a responder as a participant who completed 12 weeks of treatment and whose week 12 PI-NRS score showed at least a 30% improvement from baseline. Participants who did not complete 12 weeks are classified as non-responders. The reported unit is percentage of participants. No group-level responder counts or percentages are reported in the registry record.
What does a responder percentage describe?
As a general statistical explanation, a percentage for a binary outcome describes the observed frequency of participants meeting a specified criterion among the participants counted in the analysis. To interpret it, readers need the group denominator as well as the number meeting the criterion. A randomized comparison then needs an effect estimate that expresses the contrast between groups, together with uncertainty. The registry record does not report these primary outcome values, so neither the observed frequencies nor their contrast can be interpreted.
What would a confidence interval add?
In general, a confidence interval gives a range of values compatible with the data under the chosen statistical method and its assumptions. It conveys precision: a narrower interval indicates greater precision than a wider interval, while an interval spanning values with different substantive implications may leave substantial uncertainty. A confidence interval is not a guarantee that the true effect lies in the interval. No primary endpoint confidence interval is reported in the registry record, so the precision of the trial’s estimated effect is not available.
What can be inferred from the analysis count?
The record lists 1 analysis. That count does not identify the statistical procedure or establish whether the analysis was adjusted, stratified, or based on a particular model. The registry does not report a detailed analysis plan, the comparison statistic, handling of ties or incomplete diary data, or the method used to construct any uncertainty interval. These details are important because different methods can make different assumptions about the data and target different estimands.
The primary endpoint description names an intent-to-treat population. In general, an intent-to-treat approach seeks to analyze participants according to their randomized assignment, preserving the comparison created by randomization. However, the registry record does not explain exactly which participants were included in the primary analysis or how missing assessments were handled. The endpoint’s explicit non-responder rule for participants who did not complete 12 weeks is reported, but it does not answer every question about missing diary entries or other incomplete observations.
Why does the binary threshold matter?
As a general concept, converting a continuous or graded measure into a binary responder outcome can make a result easier to communicate, but it loses detail. Participants with different amounts of improvement can receive the same responder classification, while people on opposite sides of the threshold can be classified differently even when their scores are close. The PI-NRS itself is an eleven point scale, from 0=no pain to 10=worst pain imaginable, and pain was recorded twice each day in a diary. A percentage response result therefore summarizes a threshold applied to a pain measure rather than showing the full pattern of scores over time.
The registry’s sample-size assumptions describe a planning illustration based on the observed effect, not the trial’s own design. The stated assumptions are a two-sided significance level of 0.05, equal allocation between the two arms, and a normal approximation; the effect to detect is a stated fraction of the observed effect. These are planning assumptions, not evidence that the trial was designed using them. No numerical sample-size illustration is included in the registry entries, and no sample-size justification for the trial is reported. Such planning illustrations must not be interpreted as observed power or as proof that the trial could detect a particular effect.
More generally, over-dispersion matters when observed variation is greater than a statistical model expects. If ignored, standard errors and uncertainty estimates may be unreliable. That is a general consideration for analyses whose model assumptions do not fit the data; the registry record does not identify an over-dispersion issue or say whether any model requiring such an assessment was used. The endpoint’s binary form alone is not enough to establish which analysis method was applied.
The record also does not state whether a primary analysis was prespecified, whether interim analyses were planned or conducted, or whether any adjustments were made for multiple outcomes. Those features cannot be reconstructed from the endpoint title or the count of analyses. In the absence of a reported treatment effect and its uncertainty, statistical significance, practical magnitude, and precision cannot be judged for the primary comparison.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists 17 outcome measures. The primary outcome is a responder percentage, and the secondary outcomes include changes in the SF-MPQ total score, CRPS pain intensity ratings, sleep assessment, activity level, participant symptom assessment, and mechanically evoked allodynia ratings. These are multiple opportunities to examine outcomes. As a general statistical concept, examining multiple outcomes can increase the chance that at least one appears notable by chance if each is tested separately. Researchers may address this with prespecified priorities or statistical adjustments, but those procedures are not reported in the registry record.
The record lists 1 analysis, but does not say whether that count refers to a single statistical test, one analysis record, or another reporting convention. It does not report a multiplicity adjustment, a testing hierarchy, or which secondary outcomes were intended to support confirmatory conclusions. The registry’s skipped-analysis note says the primary outcome has several categories or time points and was not reduced to one comparison. Thus a single primary contrast cannot be recovered from the registry entries.
Missing-data information is limited. The primary endpoint definition explicitly counts participants who did not complete 12 weeks of treatment as non-responders. It does not state how missing diary entries or other absent week 12 pain ratings were handled for participants who completed treatment. Group-specific completion and missingness counts are not reported. The record identifies the primary population as intent to treat, but does not describe the exact analysis set or any sensitivity analyses.
As a general principle, missing-data assumptions matter because the result can depend on how absent outcomes are treated. A stated non-responder rule addresses treatment non-completion but does not establish the handling of every missing measurement. The registry record does not report sensitivity analyses or an assessment of how alternative missing-data assumptions might affect the primary result. This leaves both multiplicity control and the impact of incomplete outcome data uncertain.
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 |
|---|---|---|---|
| Lenalidomide | 12 | 87 | 13.8% |
| Placebo to Lenalidomide | 16 | 93 | 17.2% |
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 |
|---|---|
| Lenalidomide | 77 of 87 |
| Placebo to Lenalidomide | 72 of 93 |
Most frequent serious adverse event terms
| Event term | Organ system | Lenalidomide | Placebo to Lenalidomide |
|---|---|---|---|
| Deep vein thrombosis | Vascular disorders | 1 of 87 | 2 of 93 |
| Joint sprain | Injury, poisoning and procedural complications | 2 of 87 | 0 of 93 |
| Neuropathic pain | Nervous system disorders | 1 of 87 | 1 of 93 |
| Pregnancy NOS | Pregnancy, puerperium and perinatal conditions | 2 of 87 | 0 of 93 |
| Accidental overdose | Injury, poisoning and procedural complications | 0 of 87 | 1 of 93 |
| Foot fracture | Injury, poisoning and procedural complications | 1 of 87 | 0 of 93 |
| Hip fracture | Injury, poisoning and procedural complications | 0 of 87 | 1 of 93 |
| Thrombosis | Vascular disorders | 1 of 87 | 0 of 93 |
| Blood human chorionic gonadotropin positive | Investigations | 1 of 87 | 0 of 93 |
| Blood potassium decreased | Investigations | 1 of 87 | 0 of 93 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Lenalidomide | Placebo to Lenalidomide |
|---|---|---|---|
| Rash NOS | Skin and subcutaneous tissue disorders | 24 of 87 | 9 of 93 |
| Nausea | Gastrointestinal disorders | 14 of 87 | 15 of 93 |
| Headache | Nervous system disorders | 9 of 87 | 13 of 93 |
| Diarrhoea NOS | Gastrointestinal disorders | 11 of 87 | 10 of 93 |
| Fatigue | General disorders | 9 of 87 | 12 of 93 |
| Dizziness | Nervous system disorders | 9 of 87 | 6 of 93 |
| Constipation | Gastrointestinal disorders | 8 of 87 | 5 of 93 |
| Pruritus | Skin and subcutaneous tissue disorders | 8 of 87 | 4 of 93 |
| Insomnia | Psychiatric disorders | 7 of 87 | 5 of 93 |
| Nasopharyngitis | Respiratory, thoracic and mediastinal disorders | 6 of 87 | 5 of 93 |
Serious events with the highest arm-level rate: joint sprain (2.3%), pregnancy nos (2.3%), deep vein thrombosis (2.2%), foot fracture (1.1%), thrombosis (1.1%).
The adverse-event record gives serious adverse event counts of 12 among 87 participants at risk in the Lenalidomide group and 16 among 93 participants at risk in the Placebo to Lenalidomide group. Other adverse events are recorded for 77 among 87 participants at risk in the Lenalidomide group and 72 among 93 participants at risk in the Placebo to Lenalidomide group. These are counts of participants affected, not counts of every event, and they should be read with the group labels and denominators shown in the record.
The second group is labelled “Placebo to Lenalidomide,” reflecting the arm description that placebo participants could cross over to lenalidomide in the open-label extension. The registry entries do not give exposure timing or enough detail to attribute events to a particular treatment period. The record lists serious terms including Joint sprain at 2.3%, Pregnancy NOS at 2.3%, Deep vein thrombosis at 2.2%, Foot fracture at 1.1%, Thrombosis at 1.1%, and Blood human chorionic gonadotropin positive at 1.1%. The registry entries do not establish further context for those term percentages.
Deaths are not reported in the registry record. These adverse-event figures describe reported events and do not by themselves establish causation or allow a complete comparison of safety. The registry does not report additional context such as event timing or exposure-specific attribution.
12. What the Result Does, and Does Not, Mean
The record establishes that a randomized, quadruple-masked, placebo-controlled Phase 2 study was designed to evaluate lenalidomide in adults with CRPS type 1. It specifies a primary responder definition based on the PI-NRS and a 12-week treatment-completion rule. It also provides adverse-event counts and lists secondary outcomes. These are useful details for understanding what the study set out to measure and how some outcomes were classified.
The record does not report arm-level results for the primary endpoint, a treatment-effect estimate, a confidence interval, or a p-value. The listed secondary outcomes likewise have no reported results in the registry entries. Therefore, the posted information cannot establish the observed magnitude, direction, or precision of the primary comparison. The absence of a reported result is not evidence that the groups had identical outcomes, nor does the status TERMINATED establish what the study found. The reason for termination is not reported in the registry record.
As a general statistical distinction, a trial’s design and endpoint definition describe the question and planned measurement, whereas outcome estimates describe what was observed. A randomized design can support a comparative interpretation when relevant results and analysis details are available, but design features alone cannot answer the efficacy question. Likewise, an endpoint based on a 30% response threshold does not reveal how much pain scores changed across all participants.
The safety counts are also descriptive registry figures. Without detailed timing, exposure, and attribution information, they should not be treated as proof that a particular treatment caused an event or as a complete comparison of safety. Overall, the record documents trial structure, treatment periods, outcome definitions, and selected adverse-event reporting, while leaving the principal efficacy result and several key analysis details unavailable.
13. Why This Trial Matters Statistically
This trial is statistically notable as an example of a randomized, masked, placebo-controlled study whose central question is clear but whose posted primary comparison is not reported. The endpoint is defined as a binary response based on a pain-intensity measure, a threshold, and completion of treatment. That combination makes it especially important to distinguish the outcome rule from the outcome result: knowing how a responder was defined does not reveal how many participants responded in either group.
The endpoint also illustrates a general trade-off in outcome construction. A responder category can make a result more readily interpretable, yet it removes information about the amount and distribution of score changes. The registry specifies twice-daily diary ratings on an eleven point scale and a 30% improvement threshold, but does not report group-level scores or response frequencies. Readers therefore cannot examine whether any observed changes clustered near the threshold or varied more broadly.
Multiplicity and missing data are also relevant statistical questions. The registry lists 17 outcome measures, but does not report a testing hierarchy or adjustment for multiple comparisons. It defines treatment non-completion as non-response while leaving the handling of other missing pain ratings unspecified. Those decisions can affect the interpretation of a binary outcome and the uncertainty around a comparison.
Finally, the record distinguishes the randomized double-blind period from an optional open-label extension, including crossover from placebo to lenalidomide. That distinction matters when reading arm labels and adverse-event counts, because the record does not provide exposure-specific timing for the events. The study’s design and reporting features demonstrate why transparent outcome results, analysis details, and missing-data information are necessary for readers to assess both the size and reliability of a clinical-trial finding.
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.
A major limitation of the available registry record is that it does not report the primary endpoint results by treatment group. No responder counts or percentages, between-group estimate, confidence interval, or p-value are included. The record therefore does not permit evaluation of the size, direction, or precision of the primary comparison. The reason the study was terminated is also not reported in the registry record.
The endpoint description combines a pain-response threshold with treatment completion. Participants not completing 12 weeks are classified as non-responders, but the record does not report how many participants fell into that category in either arm. It also does not explain how missing diary entries or missing week 12 scores were handled for participants who otherwise completed treatment. The stated intent-to-treat population is not accompanied by details about the exact analysis set.
Although the record lists 17 outcome measures and 1 analysis, it does not describe a detailed statistical plan, the test or model used, any covariate adjustment, or procedures for controlling multiplicity. The primary outcome is noted as having several categories or time points and not being reduced to one comparison. The registry entries do not identify how those categories or time points were handled analytically. No interim-analysis information or sample-size justification is reported.
The safety record gives group counts and selected serious adverse-event terms, but does not provide event timing or exposure-specific attribution. The placebo group’s label reflects the option to cross over to lenalidomide during the open-label extension, while the record does not report how long participants were exposed in each period. Deaths are not reported in the registry record. These limitations constrain interpretation of both efficacy and safety from the posted registry information.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Study to Evaluate the Efficacy and Safety of Lenalidomide in the Treatment of Complex Regional Pain Syndrome Type 1 — NCT00109772.
- Registry record last updated 2013-08-28; status last verified 2013-08.
- Results first posted 2013-08-28.
- 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
This registry record describes a Phase 2, randomized, quadruple-masked, parallel-group study of oral lenalidomide versus placebo in adults with CRPS type 1. Enrollment was 184. Double-blind treatment was planned for up to 12 weeks, followed by an optional open-label extension for participants completing that period. The study status is TERMINATED; the reason is not reported in the registry record.
The primary endpoint was the percentage meeting a 30% PI-NRS improvement threshold, with non-completers classified as non-responders. The primary outcome results, statistical effect estimate, and precision measures are not reported in the registry record. The record lists 17 outcome measures and provides selected adverse-event counts and terms, but key details on the analysis, missing data, multiplicity, and event timing are not reported.