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 CNP520 Versus Placebo in Participants at Risk for the Onset of Clinical Symptoms of Alzheimer's Disease (NCT03131453), a randomized phase 2, phase 3 study. The primary outcome is Time to Event (Diagnosis of Mild Cognitive Impairment or Dementia, Due to Alzheimer's Disease (AD)).
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT03131453 |
| Phase | Phase 2, Phase 3 |
| Condition | Alzheimers Disease |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Quadruple |
| Enrollment | 1145 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Novartis Pharmaceuticals |
| Results posted | Yes |
2. Clinical Question
Population
Participants considered at risk for the onset of clinical symptoms of Alzheimer's disease based on age, APOE genotype and elevated amyloid. The primary outcome description specifies the safety analysis set, with the number at risk varying by time point.
Intervention
CNP520 capsules taken orally once daily: 50 mg or 15 mg.
Comparator
Matching placebo taken orally once daily.
Primary question
How did the probability of a first confirmed diagnosis of mild cognitive impairment or dementia due to Alzheimer's disease change over follow-up in the study groups? The registry says that the study was terminated and that the small number of confirmed events prevented time-to-event analysis.
The primary event was the first diagnosis of mild cognitive impairment or dementia due to Alzheimer's disease, after confirmation by the progression adjudication committee. A diagnosis could be triggered by an investigator diagnosis or an increase in the Clinical Dementia Rating global score; confirmation at two consecutive visits was required. The registry describes Kaplan-Meier estimates as a way to estimate event probability before specified visits, but it does not report numerical estimates in the record. The study also aimed to assess cognition, global clinical status, underlying Alzheimer's disease pathology and safety. The listed secondary outcomes include cognitive scales, MRI findings, brain-region volume and cerebrospinal fluid amyloid measures. These other outcomes do not replace the primary event question, and their results are not reported in the registry record.
3. Trial Design
The registry describes a randomized, parallel-group study of CNP520 and matching placebo. It lists phase 2 and phase 3 and an enrollment of 1145. The listed groups received CNP520 50 mg, CNP520 15 mg or matching placebo. Each capsule was taken orally once daily. The official title calls the study double-blind, while the registry's masking field says quadruple; the record therefore contains both descriptions and does not explain their relationship. Novartis Pharmaceuticals is listed as the sponsor.
The study began on 2017-08-03, and the listed primary completion date is 2020-03-26. Its status is terminated. The primary outcome timeframe runs from baseline to the last cognitive assessment performed, up to day 648. The registry states that only confirmed events collected up to the data cut-off point were counted because of early termination. It also says that the small number of events meant time-to-event analysis could not be performed.
The target population was people considered at risk for the onset of clinical symptoms of Alzheimer's disease based on age, APOE genotype and elevated amyloid. The registry record does not give further eligibility criteria, group-specific enrollment totals, treatment duration, adherence information or details of the randomization procedure. It does not report the reason for termination in the information. These omissions limit how fully the conduct and participant experience can be reconstructed from the record alone.
Random allocation is intended to make the groups comparable on average at the start of a study, while a parallel-group design assigns participants to a study group that is followed over time. Masking is intended to reduce the influence of knowledge about assigned treatment on conduct or assessment. Those are general design concepts; the registry's labels alone do not establish how successfully these aims were achieved in practice.
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: 8970 participants were screened
Overall Study
| Stage | CNP520 50 mg | CNP520 15 mg | Placebo |
|---|---|---|---|
| STARTED | 456 | 233 | 456 |
| Patient Misrandomized | 1 | 0 | 0 |
| COMPLETED | 0 | 0 | 0 |
| NOT COMPLETED | 456 | 233 | 456 |
Reasons for not completing this period:
| Reason | CNP520 50 mg | CNP520 15 mg | Placebo |
|---|---|---|---|
| Study terminated by Sponsor | 424 | 222 | 438 |
| Withdrawal by Subject | 18 | 7 | 13 |
| Adverse Event | 10 | 3 | 3 |
| Lost to Follow-up | 1 | 0 | 1 |
| Physician Decision | 1 | 0 | 1 |
| Non-compliance with study treatment | 1 | 0 | 0 |
| Technical problems | 1 | 0 | 0 |
| Protocol deviation | 0 | 1 | 0 |
Analysis population for the primary outcome, as defined in the registry: Safety analysis set; n=number of participants at risk to experience an event at the time-point
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: One patient was misrandomized and not included in the CNP520 50mg arm
| Characteristic | Unit | CNP520 50 mg | CNP520 15 mg | Placebo | Total |
|---|---|---|---|---|---|
| Participants analysed | 455 | 233 | 456 | 1144 | |
| Age, Customized: <=64 | participants | 76 | 45 | 80 | 201 |
| Age, Customized: 65-69 | participants | 181 | 82 | 162 | 425 |
| Age, Customized: >70 | participants | 198 | 106 | 214 | 518 |
| Sex: Female, Male: Female | Participants | 284 | 148 | 288 | 720 |
| Sex: Female, Male: Male | Participants | 171 | 85 | 168 | 424 |
| Race/Ethnicity, Customized: Caucasian | participants | 416 | 213 | 422 | 1051 |
| Race/Ethnicity, Customized: Black | participants | 7 | 1 | 5 | 13 |
| Race/Ethnicity, Customized: Asian | participants | 18 | 12 | 22 | 52 |
| Race/Ethnicity, Customized: Native American | participants | 3 | 2 | 1 | 6 |
| Race/Ethnicity, Customized: Pacific Islander | participants | 2 | 1 | 0 | 3 |
| Race/Ethnicity, Customized: Other | participants | 4 | 2 | 0 | 6 |
| Race/Ethnicity, Customized: Unknown | participants | 5 | 2 | 6 | 13 |
| Baseline cognitive scale assessment: APCC score | scores on a scale | 74.6 (SD 6.68) | 75.8 (SD 6.81) | 74.9 (SD 7.16) | 75.0 (SD 6.91) |
| Baseline cognitive scale assessment: RBANS Total | scores on a scale | 100.5 (SD 11.96) | 102.0 (SD 12.09) | 100.7 (SD 12.42) | 100.9 (SD 12.18) |
| Baseline cognitive scale assessment: CDR-SOB | scores on a scale | 0.19 (SD 0.389) | 0.16 (SD 0.358) | 0.14 (SD 0.358) | 0.16 (SD 0.371) |
6. Primary Endpoint
The registry lists the primary outcome as Time to Event (Diagnosis of Mild Cognitive Impairment or Dementia, Due to Alzheimer's Disease (AD)), measured over Baseline to last cognitive assessment performed (up to day 648).
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | 95% Confidence Interval |
| Unit | probability of an event |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint concerns time to the first confirmed diagnosis of mild cognitive impairment or dementia due to Alzheimer's disease. It is a clinical event endpoint: rather than measuring only a score on a cognitive test, it records whether and when a qualifying diagnosis occurs. The event required adjudication by the progression adjudication committee and confirmation at two consecutive visits. The committee's review could be triggered by an investigator diagnosis or an increase in the Clinical Dementia Rating global score.
The registry describes the outcome as the probability of an event and specifies a 95% confidence interval as the dispersion measure. The observation period was baseline to the last cognitive assessment performed, up to day 648. Participants without a confirmed event were censored at the last date their diagnostic classification was assessed. In general, censoring allows follow-up information to contribute up to the point when event status is no longer observed; interpretation depends on the assumptions behind that approach.
In general, time-to-event outcomes can use information about both whether an event occurred and the timing of that event, while allowing follow-up lengths to differ. They are often useful when a clinical outcome develops over time rather than being measured at one fixed visit. Here, however, the registry explicitly states that early termination left too few confirmed events for time-to-event analysis. Numerical event probabilities and their confidence intervals are not reported in the registry record, so the size and precision of any group differences cannot be described from this record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The primary result cannot be interpreted as an estimated treatment effect because the registry says that time-to-event analysis could not be performed. It reports that only a small number of confirmed events were observed before the study ended, but it does not give the event counts, group-specific Kaplan-Meier estimates, confidence intervals or a treatment-effect estimate. Consequently, the record does not establish the direction or magnitude of a difference between CNP520 and placebo for the primary outcome.
The planned endpoint was based on confirmed diagnoses of mild cognitive impairment or dementia due to Alzheimer's disease. An event required adjudication and confirmation at two consecutive visits, and observations without a confirmed event were censored at the last diagnostic classification assessment. These requirements define what counted as an endpoint event; they do not provide enough information to infer how many participants experienced one. The registry also notes that only confirmed events collected through the data cut-off were counted.
A confidence interval, in general, expresses uncertainty around an estimated quantity under the statistical method used. A narrow interval generally indicates greater precision than a wide one, but neither width nor coverage can be assessed without the interval itself. Although the endpoint specifies a 95% confidence interval, no numerical interval is included in the registry record. A p-value or other test result for the primary comparison is also not reported in the registry record.
The study's early termination is important context for interpreting the unavailable analysis. With few observed events, an estimate of event timing or a comparison between groups may be imprecise or not estimable using the planned approach. This is a general statistical consideration, not a claim about a particular estimate in this study. The record does not report the reason for termination, a planned event target, an interim analysis, or whether stopping was related to efficacy or safety. None of those explanations can be inferred from the status alone.
The registry lists secondary outcomes concerning cognitive scales, MRI abnormalities, brain-region volume and cerebrospinal fluid amyloid measures. It does not report numerical findings for those outcomes in the record. Their presence in the outcome list cannot be treated as evidence of a measured effect. The appropriate reading is therefore limited: the registry describes the design and intended outcomes, records termination and limited event collection, and does not provide an analyzable primary time-to-event result or enough numerical secondary results to establish a broader pattern.
9. Statistical Methods Explained
The registry identifies a time-to-event endpoint but states that time-to-event analysis could not be performed because only a small number of events were observed before termination. The methods below explain the general statistical concepts relevant to the endpoint; they are not a claim that a particular model or test was used for a final treatment comparison. The analysis procedure beyond the registry's description is not reported in the registry record.
What does time to event mean?
In general, time-to-event analysis considers both the occurrence of a defined event and the time until it occurs. This can be useful when participants have different lengths of follow-up. In this study the event was the first confirmed diagnosis of mild cognitive impairment or dementia due to Alzheimer's disease, whichever occurred first. The registry describes Kaplan-Meier estimates for estimating the probability that a participant would experience an event before a specified visit. It does not report numerical estimates or a completed time-to-event comparison.
Kaplan-Meier estimation, in general, updates an estimate of the probability of remaining event-free as events occur, while accounting for participants whose follow-up ends before an event is observed. Its interpretation relies on how censoring relates to the chance of later experiencing the event. The registry states that a participant without a confirmed event was censored at the last date when diagnostic classification was assessed. It does not describe additional assumptions or sensitivity analyses for censoring.
Why does confirmation matter?
The event definition required review by the progression adjudication committee and confirmation at two consecutive visits. The committee review could be triggered by an investigator diagnosis or an increase in the Clinical Dementia Rating global score. In general, a clearly specified event definition helps keep outcome classification consistent. Requiring confirmation can distinguish a qualifying event from a preliminary observation, but it also means that only events meeting the confirmation rule count in the primary outcome. The record does not report how many potential diagnoses were reviewed, how many were confirmed, or the adjudication procedures beyond the stated rule.
What do censoring and follow-up limits imply?
Censoring means that the event was not confirmed during the observed period, or that the available observation ended before a qualifying event was recorded. It does not mean that an event never occurred. The registry defines the censoring date as the last date on which diagnostic classification was assessed. The endpoint window ran from baseline to the last cognitive assessment performed, up to day 648. The record also says that only confirmed events collected up to the data cut-off point were counted. These details define the period and rules represented by the endpoint, but do not tell readers how much follow-up each group contributed.
In general, early termination can reduce the information available for estimating event probabilities, especially when relatively few events have accumulated. A small number of events can make estimates uncertain and can prevent some analyses from being carried out. The registry explicitly attributes the inability to analyze time to event to the small number of events observed after early termination. It does not report a numerical event total, an event-rate estimate, or a completed model result.
How should the confidence interval be read?
The endpoint lists a 95% confidence interval. In general, a confidence interval describes uncertainty around an estimate under a statistical procedure and its assumptions. It is not itself a measure of clinical importance, and its width is informative about precision only when an estimate and interval are available. No numerical primary confidence interval is reported in the registry record, so precision cannot be evaluated from the listed dispersion measure alone. A confidence interval for a group comparison is also not reported.
What is not described?
The registry record does not report a detailed statistical analysis plan, a final inferential test, a model specification, covariate adjustment, or handling of competing events. It does not report an interim-analysis plan or an explanation of whether any such review occurred. These details should not be inferred from the endpoint name, the study's phase labels or its masking description. The record lists 15 outcome measures and no analyses, but this alone does not establish what analyses were planned outside the registry record or performed but not posted.
Sample-size figures elsewhere in the posted material are described as planning illustrations based on an observed effect, using a two-sided significance level of 0.05, equal allocation and a normal approximation. The effect to detect is expressed as a stated fraction of the observed effect. For time-to-event outcomes, such illustrations concern total events; for other outcomes, they concern participants per arm. Such calculations are hypothetical planning aids, not observed power and not evidence that the terminated study achieved a target. The registry does not report the trial's own sample-size justification, and the primary endpoint was not reduced to a single comparison for the calculation. The illustration therefore cannot substitute for the missing primary analysis.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists 15 outcome measures, including the primary time-to-event outcome and secondary measures of cognition, MRI findings, brain-region volume and cerebrospinal fluid amyloid. It lists no analyses. A list of outcomes indicates what was registered for assessment; it does not show which outcomes were analyzed, how many comparisons were made, or which results were selected for reporting.
Multiplicity is a general statistical issue that arises when many hypotheses or outcomes are assessed. Without an adjustment or a prespecified hierarchy, the chance of at least one apparently unusual result can increase across repeated testing. The registry record does not report a multiplicity strategy, such as adjustment, outcome hierarchy or a gatekeeping procedure. It is therefore not possible to determine from the record whether or how multiplicity was addressed.
Missing-data methods for the non-primary outcomes are not reported in the registry record. For the primary outcome, the record does specify that a participant without a confirmed event was censored at the last date when diagnostic classification was assessed. It does not report other missing-data assumptions or sensitivity analyses. Censoring is part of the definition of follow-up for a time-to-event analysis; it does not, on its own, explain missing measurements for cognitive or biomarker outcomes.
The primary outcome population is described as the safety analysis set, with the number at risk stated for each time point. The registry record does not describe other analysis populations, such as an intention-to-treat population, or explain how participants were assigned to analysis sets. The listed enrollment is 1145, but the record does not provide group-specific enrollment or outcome populations for the primary endpoint. These gaps limit assessment of the analysis population and completeness of follow-up.
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 |
|---|---|---|---|
| CNP520 50 mg | 15 | 455 | 3.3% |
| CNP520 15 mg | 9 | 233 | 3.9% |
| Placebo | 15 | 456 | 3.3% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| CNP520 50 mg | 0 of 455 |
| CNP520 15 mg | 0 of 233 |
| Placebo | 0 of 456 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 2.5% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| CNP520 50 mg | 137 of 455 |
| CNP520 15 mg | 62 of 233 |
| Placebo | 89 of 456 |
Most frequent serious adverse event terms
| Event term | Organ system | CNP520 50 mg | CNP520 15 mg | Placebo |
|---|---|---|---|---|
| Coronary artery disease | Cardiac disorders | 2 of 455 | 1 of 233 | 0 of 456 |
| Supraventricular tachycardia | Cardiac disorders | 0 of 455 | 1 of 233 | 1 of 456 |
| Seizure | Nervous system disorders | 1 of 455 | 1 of 233 | 0 of 456 |
| Aortic valve incompetence | Cardiac disorders | 0 of 455 | 1 of 233 | 0 of 456 |
| Mitral valve incompetence | Cardiac disorders | 0 of 455 | 1 of 233 | 0 of 456 |
| Colitis ulcerative | Gastrointestinal disorders | 0 of 455 | 0 of 233 | 1 of 456 |
| Nausea | Gastrointestinal disorders | 0 of 455 | 1 of 233 | 0 of 456 |
| Pancreatitis | Gastrointestinal disorders | 0 of 455 | 1 of 233 | 0 of 456 |
| Non-cardiac chest pain | General disorders | 0 of 455 | 0 of 233 | 1 of 456 |
| Drug-induced liver injury | Hepatobiliary disorders | 1 of 455 | 0 of 233 | 0 of 456 |
Most frequent non-serious adverse event terms
| Event term | Organ system | CNP520 50 mg | CNP520 15 mg | Placebo |
|---|---|---|---|---|
| Pruritus | Skin and subcutaneous tissue disorders | 32 of 455 | 12 of 233 | 16 of 456 |
| Nasopharyngitis | Infections and infestations | 22 of 455 | 9 of 233 | 11 of 456 |
| Upper respiratory tract infection | Infections and infestations | 18 of 455 | 5 of 233 | 16 of 456 |
| Headache | Nervous system disorders | 12 of 455 | 8 of 233 | 15 of 456 |
| Anxiety | Psychiatric disorders | 21 of 455 | 4 of 233 | 8 of 456 |
| Weight decreased | Investigations | 19 of 455 | 3 of 233 | 7 of 456 |
| Dizziness | Nervous system disorders | 14 of 455 | 7 of 233 | 8 of 456 |
| Arthralgia | Musculoskeletal and connective tissue disorders | 11 of 455 | 6 of 233 | 11 of 456 |
| Abnormal dreams | Psychiatric disorders | 18 of 455 | 7 of 233 | 3 of 456 |
| Urinary tract infection | Infections and infestations | 8 of 455 | 8 of 233 | 7 of 456 |
Serious events with the highest arm-level rate: coronary artery disease (0.4%), aortic valve incompetence (0.4%), mitral valve incompetence (0.4%), supraventricular tachycardia (0.4%), nausea (0.4%).
The registry reports serious and other adverse-event counts by group, along with the number at risk for each category. For CNP520 50 mg, 15 participants with serious adverse events and 137 with other adverse events are listed, with 455 at risk in each category. For CNP520 15 mg, 9 participants with serious adverse events and 62 with other adverse events are listed, with 233 at risk in each category. For placebo, 15 participants with serious adverse events and 89 with other adverse events are listed, with 456 at risk in each category. Deaths are listed as 0 in each group.
These are descriptive counts, not estimates of whether treatment caused an event. The registry record does not provide a comparison adjusted for follow-up duration, participant characteristics or exposure. The number at risk is the denominator stated for the corresponding category; it should not be interpreted as proof that every participant had the same duration of observation. The record does not report detailed definitions or event-level timing in the information.
The listed serious-event terms include coronary artery disease, aortic valve incompetence, mitral valve incompetence, supraventricular tachycardia, nausea and pancreatitis, each reported as 0.4%. The record does not provide arm-specific percentages for these terms in the information. Counts and terms should be read as safety reporting, not as a statistical test or a causal conclusion.
12. What the Result Does, and Does Not, Mean
The registry record establishes that a randomized, parallel-group study of CNP520 and matching placebo was conducted in people considered at risk for the onset of clinical symptoms of Alzheimer's disease, and that the study was terminated. It identifies the intended primary outcome as time to the first confirmed diagnosis of mild cognitive impairment or dementia due to Alzheimer's disease. It also states that the limited number of confirmed events meant this time-to-event outcome could not be analyzed.
That limitation is central. The registry record does not provide a numerical primary event probability, a group comparison, a confidence interval or a p-value. It therefore cannot support a conclusion about the direction, size or precision of a primary treatment difference. Lack of an analyzable result is not evidence that the groups were the same, and it is not evidence that either group had a particular outcome. It means the primary comparison is unavailable in the record.
The record lists other outcomes, including clinical and cognitive scales, MRI abnormalities, brain-region volume and cerebrospinal fluid amyloid measures. It does not give their numerical results in the information. The outcome list shows the range of intended assessments, but it does not establish that all results were collected, analyzed or reported. Nor can the safety counts alone establish whether an event was caused by a study intervention.
Early termination and limited event collection affect what can be learned from this record, but the reason for termination is not reported in the registry record. No explanation should be inferred from the status or from the absence of a primary analysis. The record also does not report the trial's sample-size justification, a detailed statistical plan or an account of interim review. These omissions prevent a fuller assessment of how the study's final information compares with its original plans.
In general, a randomized design can support a fair comparison when assignment, follow-up and analysis are carried out appropriately. The design label alone cannot replace outcome estimates or information about implementation. Here the available account supports a description of the study's design, endpoint definition, termination and posted adverse-event counts, but not a claim that CNP520 improved or worsened the primary clinical outcome.
13. Why This Trial Matters Statistically
This trial is statistically important because it illustrates the difference between specifying a clinically meaningful endpoint and obtaining enough observed events to analyze it. The primary question concerned time to a confirmed diagnosis, an outcome that depends on accumulating qualifying events during follow-up. The registry says early termination left only a small number of confirmed events and prevented time-to-event analysis. When an endpoint cannot be analyzed, a randomized design does not by itself produce a treatment-effect estimate.
The endpoint definition also shows how event ascertainment can shape an analysis. A diagnosis had to be adjudicated and confirmed at two consecutive visits, and participants without a confirmed event were censored at their last diagnostic classification. These rules support a consistent definition, while also making clear that the analysis depends on confirmed events and observed follow-up. The registry supplies the rules but not the event counts, estimated probabilities or uncertainty intervals needed to evaluate the result.
The record further illustrates why planned outcomes, analyses and reported results are different things. It lists 15 outcome measures but no analyses. The secondary outcome list spans clinical, cognitive, imaging and biomarker measures, yet numerical results for them are not reported in the registry record. A broad outcome program cannot be interpreted as a set of findings without the corresponding estimates and uncertainty.
Finally, the safety counts are useful descriptive information but are not a substitute for a comparative analysis. Their interpretation depends on the number at risk and the available observation, and the record does not provide adjusted comparisons or detailed exposure information. Overall, the registry demonstrates the importance of transparent reporting about endpoint definitions, censoring, analysis feasibility and the distinction between descriptive counts and inferential evidence.
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 most consequential limitation is stated directly in the registry: early termination left a small number of confirmed primary events, so time-to-event analysis could not be performed. The record provides no numerical primary event estimates, group comparison, confidence interval or p-value. The primary question therefore remains without a reported statistical answer in this record.
The reason for termination is not reported in the registry record. The record also does not give a planned event target, sample-size justification, detailed statistical analysis plan or an explanation of interim review. Without those details, readers cannot determine how the observed follow-up and event accumulation compared with the study's original statistical aims, or whether a planned analysis was modified.
The endpoint description identifies a safety analysis set and explains how participants without confirmed events were censored. However, group-specific primary endpoint populations, event counts and follow-up distributions are not reported in the record. The number at risk can vary by time point, but the underlying estimates are unavailable. The record also does not report sensitivity analyses for censoring or additional assumptions about incomplete diagnostic follow-up.
The registry lists a range of secondary outcomes, but their numerical results and analysis details are not reported. Multiplicity handling and methods for missing secondary-outcome data are not reported in the registry record. The masking descriptions also differ: the official title says double-blind, while the registry masking field says quadruple. The record does not explain this difference. Finally, adverse-event counts are descriptive, and the summarized record does not provide detailed exposure, duration or adjusted comparisons. These limitations restrict both efficacy interpretation and detailed safety comparison.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: A Study of CNP520 Versus Placebo in Participants at Risk for the Onset of Clinical Symptoms of Alzheimer's Disease — NCT03131453.
- Registry record last updated 2021-08-05; status last verified 2021-08.
- Results first posted 2021-08-05.
- 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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18. Record Summary
The registry describes a randomized, parallel-group study of CNP520 50 mg, CNP520 15 mg and matching placebo in people considered at risk for the onset of clinical symptoms of Alzheimer's disease. Enrollment is listed as 1145; the study is listed as phase 2 and phase 3 and is terminated. The primary outcome was time to a first confirmed diagnosis of mild cognitive impairment or dementia due to Alzheimer's disease.
The registry states that only a small number of confirmed events were collected before termination and that time-to-event analysis could not be performed. Numerical primary estimates and a treatment comparison are not reported in the registry record. The record lists secondary clinical, cognitive, imaging and biomarker outcomes, but numerical findings for those outcomes are not reported in the information. Descriptive serious and other adverse-event counts and deaths by group are reported, without a causal interpretation.