← Clinical Trials
Cardiovascular Disease Phase 4 Time-to-Event Analysis NCT02019264

A Study to Evaluate the Effect of Long-term Treatment With BELVIQ (Lorcaserin HCl) on the Incidence of Major Adverse Cardiovascular Events and Conversion to Type 2 Diabetes Mellitus in Obese and Overweight Subjects With Cardiovascular Disease or Multiple Cardiovascular Risk Factors: Complete Statistical Analysis

This analysis examines the primary time-to-first MACE outcome and the registry’s reported comparisons of lorcaserin with placebo. It also considers the trial design, secondary outcomes, precision, planning illustrations, and adverse-event counts.

Trial start: 2014-01-24  ·  Enrollment: 14673  ·  Sponsor: Eisai Inc.
Scope of this record

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 to Evaluate the Effect of Long-term Treatment With BELVIQ (Lorcaserin HCl) on the Incidence of Major Adverse Cardiovascular Events and Conversion to Type 2 Diabetes Mellitus in Obese and Overweight Subjects With Cardiovascular Disease or Multiple Cardiovascular Risk Factors (NCT02019264), a randomized phase 4 study. The primary outcome is Time From Randomization to First Occurrence of Major Adverse Cardiovascular Events (MACE) at Interim Analysis.

14673
Enrollment
Phase 4
2
Arms
In the primary outcome
1.00
Hazard ratio
Placebo vs Lorcaserin 10 mg
0.84–1.20
95% CI
Two-sided
FeatureRegistry value
ClinicalTrials.gov identifierNCT02019264
PhasePhase 4
ConditionCardiovascular Disease, High Cardiovascular Risk, Obesity
AllocationRandomized
Design modelParallel
MaskingDouble
Enrollment14673
Arms in the primary outcome2
Lead sponsorEisai Inc.
Results postedYes

2. Clinical Question

Population

Overweight and obese participants with cardiovascular disease and/or multiple cardiovascular risk factors were eligible for the study. The registry lists cardiovascular disease, high cardiovascular risk, obesity, overweight, and type 2 diabetes among the conditions. The primary analysis used the intent-to-treat set; the description says events were counted whether they occurred while participants were on or off treatment. Participants without events were censored at their last study contact or at the visit following sponsor notification of study completion, whichever occurred first. Further eligibility criteria and details about the analysis population are not reported in the registry record.

Intervention

The active-treatment arm received lorcaserin hydrochloride 10 mg twice daily. The registry identifies the drug as BELVIQ (lorcaserin HCl) and describes the study as long-term treatment. The record does not provide additional details about adherence, treatment interruptions, or dose changes in the information reported for this outcome.

Comparator

The comparison group received placebo twice daily. Participants were allocated at random in a double-blind, parallel-group, placebo-controlled study. The registry lists 6000 participants in each arm for the primary outcome. The information available does not describe whether masking was assessed or how treatment allocation was concealed.

Primary question

The primary endpoint was time from randomization to the first occurrence of major adverse cardiovascular events, defined as myocardial infarction, stroke, or cardiovascular death. The reported comparison is a hazard ratio of 1.005, with a 97.5% confidence interval from 0.842 to 1.198. The registry identifies the analysis as non-inferiority, but the non-inferiority margin is not reported in the registry record. The estimate and interval therefore describe the reported comparison, but do not by themselves establish whether the prespecified non-inferiority criterion was met.

3. Trial Design

This was a randomized, double-blind, placebo-controlled, parallel-group phase 4 study sponsored by Eisai Inc. It enrolled 14673 participants and is listed as completed. The registry gives a start date of 2014-01-24 and a primary completion date of 2018-05-14. The brief description identifies the setting as multicenter and the population as overweight and obese subjects with cardiovascular disease and/or multiple cardiovascular risk factors.

Participants were assigned to lorcaserin hydrochloride 10 mg twice daily or placebo twice daily. The primary outcome assessed time from randomization to the first occurrence of MACE through Month 42, using the intent-to-treat set. The outcome description specifies that events counted whether they occurred on or off treatment. Those without an event were censored at their last study contact or at the visit following sponsor notification of study completion, whichever occurred first.

The registry lists 6000 participants per arm for the primary outcome. It also reports an interim analysis, but further information about the interim-analysis plan, including its timing, decision rules, or any adjustment to the statistical testing, is not reported in the registry record. The original sample-size justification, planned event target, and study-specific assumptions used to design the trial are also not reported in the registry record. The planning illustrations associated with the posted comparison are not the original design calculation.

The study included secondary outcomes on diabetes conversion, glucose homeostasis, mortality, renal impairment, MACE components, and HbA1c. The record lists 15 outcome measures and 20 analyses overall. The registry does not give complete details about the analysis population and missing-data handling for every secondary outcome. Consequently, the primary design and analysis description is more complete than the information available for interpreting the full set of outcomes.

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 14,673 participants were screened and enrolled, of which 2673 participants were screen failures and 12,000 were randomized to receive lorcaserin hydrochloride (HCl) or placebo.

Overall Study

StagePlaceboLorcaserin 10 mg
STARTED60006000
Safety Analysis Set59925995
COMPLETED57525793
NOT COMPLETED248207

Reasons for not completing this period:

ReasonPlaceboLorcaserin 10 mg
Not treated64
Lost to Follow-up5047
Withdrawal by Subject142117
Administrative reason3628
Missing1411

Analysis population for the primary outcome, as defined in the registry: The total time analysis set using the intent-to-treat (ITT) set, events were counted that occurred while participants were on and off treatment. Participants with no events were censored at their last study contact or at the visit following sponsor notification of study completion, whichever occurred first.

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: The full analysis (FA) set included all randomized participants regardless of whether they took study drug or not.

CharacteristicUnitPlaceboLorcaserin 10 mgTotal
Participants analysed6000600012000
Age, Continuousyears63.7 (SD 8.31)63.5 (SD 8.33)63.6 (SD 8.32)
Sex: Female, Male: FemaleParticipants218621124298
Sex: Female, Male: MaleParticipants381438887702
Ethnicity (NIH/OMB): Hispanic or LatinoParticipants5365021038
Ethnicity (NIH/OMB): Not Hispanic or LatinoParticipants5464549810962
Ethnicity (NIH/OMB): Unknown or Not ReportedParticipants000
Race (NIH/OMB): American Indian or Alaska NativeParticipants212647
Race (NIH/OMB): AsianParticipants7485159
Race (NIH/OMB): Native Hawaiian or Other Pacific IslanderParticipants233053
Race (NIH/OMB): Black or African AmericanParticipants466454920
Race (NIH/OMB): WhiteParticipants5331530910640
Race (NIH/OMB): More than one raceParticipants8596181
Race (NIH/OMB): Unknown or Not ReportedParticipants000

6. Primary Endpoint

The registry lists the primary outcome as Time From Randomization to First Occurrence of Major Adverse Cardiovascular Events (MACE) at Interim Analysis, measured over Baseline up to Month 42.

ElementRegistry entry
Result typeMedian
Measure of spread95% Confidence Interval
Unitdays
Endpoint classificationTime-to-Event Analysis

The primary endpoint measures the time from randomization until a participant first experiences myocardial infarction, stroke, or cardiovascular death. It is a time-to-event outcome: both whether an event occurred and how long participants were followed without an event contribute to the analysis. Participants who had no recorded event were censored according to the follow-up rule described in the registry.

A time-to-first-event endpoint is useful when the research question concerns how quickly participants experience a clinically important event, rather than only the proportion with an event at a single fixed visit. It can incorporate information from participants with different follow-up durations, provided that the analysis and censoring assumptions are appropriate. The registry says that the outcome was assessed using the Kaplan-Meier estimate and Greenwood formula. In general, Kaplan-Meier methods estimate event-free experience over time while accounting for censoring; Greenwood’s formula is used to estimate uncertainty in that estimate.

The posted primary results are expressed as a hazard ratio rather than as a median time or an absolute event risk. The registry does not report arm-specific median times for this endpoint. A hazard ratio summarizes the relative event rate over follow-up under the model used, and should not be read as a difference in median survival time or as an absolute difference in the probability of an event. The registry labels the analysis non-inferiority, but does not report the margin needed to evaluate that framework fully.

7. Results Posted in the Registry

Hazard ratio: Placebo vs Lorcaserin 10 mg

1.00

95% CI: 0.84 to 1.20

As reported in the registry

Treatment effect versus the control arm
Forest plot of hazard ratio (as reported) vs control (95% CI)Placebo vs Lorcaserin 10 mg0.820.890.961.051.141.23hazard ratio (as reported) vs control (95% CI)

8. Secondary Efficacy Endpoints

The registry also posts results for secondary outcomes. For each outcome below, the endpoint type, the test applied to the posted summary statistics, the result and its interpretation are given in turn. Secondary endpoints are usually not adjusted for multiple testing, so they support rather than confirm the primary finding.

Secondary outcomeTypeEffect measureEstimate (95% CI)Planning size, 80% power
Time From Randomization to Conversion to Type 2 Diabetes Mellitus (T2DM) for Participants With Prediabetes at BaselineTime-to-Event AnalysisHazard ratio0.81 (0.66 to 0.99)683 events
Time From Randomization to Event of All-cause MortalityTime-to-Event AnalysisHazard ratio1.08 (0.89 to 1.31)5,055 events
Time From Randomization to Conversion to Normal Glucose Homeostasis in Participants With Prediabetes at BaselineTime-to-Event AnalysisHazard ratio1.12 (0.95 to 1.33)2,298 events

Time From Randomization to Conversion to Type 2 Diabetes Mellitus (T2DM) for Participants With Prediabetes at Baseline

Treatment effect versus the control arm
Forest plot of hazard ratio (as reported) vs control (95% CI)Placebo vs Lorcaserin 10 mg0.640.700.770.850.941.03hazard ratio (as reported) vs control (95% CI)

Time From Randomization to Event of All-cause Mortality

Treatment effect versus the control arm
Forest plot of hazard ratio (as reported) vs control (95% CI)Placebo vs Lorcaserin 10 mg0.870.951.031.131.241.35hazard ratio (as reported) vs control (95% CI)

Time From Randomization to Conversion to Normal Glucose Homeostasis in Participants With Prediabetes at Baseline

Treatment effect versus the control arm
Forest plot of hazard ratio (as reported) vs control (95% CI)Placebo vs Lorcaserin 10 mg0.921.001.081.171.271.37hazard ratio (as reported) vs control (95% CI)

The secondary outcomes cover several domains, including conversion to type 2 diabetes among participants with prediabetes, all-cause mortality, conversion to normal glucose homeostasis, MACE components, renal outcomes, and HbA1c. The registry lists 15 outcome measures and 20 analyses overall, while the posted secondary comparisons include different analysis populations and follow-up periods. This breadth means the secondary results address related but distinct questions rather than serving as repeated measurements of the primary MACE endpoint.

Across the three secondary comparisons with reported hazard ratios, the diabetes-conversion result among participants with prediabetes has a confidence interval that excludes 1, whereas the intervals for all-cause mortality and conversion to normal glucose homeostasis include 1. This pattern does not alter the primary estimate or resolve its non-inferiority interpretation. Different endpoints, populations, and event processes can yield different results, and the registry does not report enough detail to treat one as a direct confirmation or refutation of another.

Unadjusted secondary results generally carry less confirmatory weight when many outcomes are examined, because the chance of at least one apparently unusual result can rise with repeated testing. In general, multiplicity procedures can control that risk, but adjustment for multiple comparisons is not reported in the registry record. The status of each secondary outcome in any prespecified testing hierarchy is also not reported. The results are therefore useful as secondary evidence and as questions for further study, but should not be interpreted as if each were an independently confirmed primary finding.

The posted values should be read with attention to the stated population and timeframe for each outcome. The diabetes analysis is restricted to participants with prediabetes at baseline, unlike the broader primary outcome analysis. The registry does not report all details needed to assess missing observations, subgroup rules, or the full analysis plan across the secondary measures.

Secondary outcomes registered for this trial, for reference (only those above were recalculated):

9. Statistical Interpretation

Clinical Biostats interpretation

The primary reported hazard ratio for placebo versus lorcaserin 10 mg is 1.005, with a 97.5% confidence interval from 0.842 to 1.198. The estimate is close to 1, the value corresponding to equal hazards in the comparison as expressed. The interval includes 1, so these data do not establish a conventional difference in either direction at the level represented by that interval. This is a description of the posted estimate and its uncertainty, not a conclusion that the treatments are equivalent.

The registry classifies the primary analysis as non-inferiority and reports p < 0.001. Non-inferiority is assessed against a prespecified margin: the question is whether the data rule out an unacceptable worsening beyond that margin. The margin is not reported in the registry record. Without it, the reported hazard ratio, confidence interval, and p-value cannot be used to verify the non-inferiority criterion from the available record. The p-value should be read in the context of the sponsor’s stated non-inferiority analysis, not as a conventional test that the two arms differ.

The registered endpoint is time to the first MACE event, assessed through Month 42. Its analysis includes events occurring on and off treatment, and uses the intent-to-treat set. This means the primary comparison follows the randomized groups for analysis as described, rather than restricting the endpoint to events during active treatment. The registry reports censoring for participants without events, but further details about censoring assumptions and sensitivity analyses are not reported in the registry record.

The secondary outcomes add context but do not replace the primary endpoint. The diabetes-conversion comparison among participants with prediabetes has a reported hazard ratio whose confidence interval does not include 1; the reported comparisons for all-cause mortality and conversion to normal glucose homeostasis have intervals that include 1. These are distinct outcomes and analysis populations, and the registry lists numerous analyses. Their statistical results should therefore be interpreted as secondary evidence, especially because adjustment for testing multiple outcomes is not reported in the registry record.

Hazard ratios describe relative event rates, not absolute risk differences. The record does not provide the primary event counts or absolute event risks needed to quantify an absolute difference in MACE from these results. Nor does it report enough information to infer the likely experience of an individual participant. The results describe the randomized comparison and follow-up recorded for this study, with uncertainty represented by the reported interval.

10. Statistical Methods Explained

The primary outcome is time from randomization to first MACE, a time-to-event measure. Each participant contributes follow-up until an event or censoring. The registry states that the analysis used the intent-to-treat set, counted events occurring on and off treatment, and censored participants with no event at their last study contact or at the visit following sponsor notification of study completion, whichever occurred first. How censoring was handled in other circumstances is not reported in the registry record.

What does Kaplan-Meier estimation do?

In general, the Kaplan-Meier method estimates the probability of remaining free of the event over time while accounting for participants whose follow-up ends before an event is observed. A censored participant contributes information up to the point of censoring but is not treated as having experienced the event. This approach relies on assumptions about censoring; in general, the estimate can be biased if censoring is related to future event risk in a way the analysis does not account for. The registry names Kaplan-Meier estimation but does not report diagnostic checks or sensitivity analyses for those assumptions.

What does Greenwood’s formula contribute?

In general, Greenwood’s formula estimates the sampling variance of the Kaplan-Meier estimate. That variance is used to express uncertainty, commonly through a confidence interval. It does not remove uncertainty or correct bias from an inappropriate censoring process. The registry says Greenwood’s formula was used for the primary outcome, but does not report further computational details.

How should the hazard ratio be read?

The posted comparison reports a hazard ratio for placebo versus lorcaserin 10 mg. In general, a hazard ratio compares the instantaneous event rates between groups among participants who have not yet experienced the event, under the model and assumptions used. A value of 1 represents equal hazards in the comparison’s orientation. A value on one side of 1 indicates a higher relative hazard for the group in the numerator of the reported comparison, and a value on the other side indicates a lower relative hazard. It is not an absolute risk difference, a ratio of cumulative event probabilities, or a ratio of median times.

The registry labels the primary analysis as non-inferiority. In general, a non-inferiority analysis evaluates whether a confidence bound excludes a prespecified degree of disadvantage, defined by a margin. The margin and other detailed testing rules are not reported in the registry record. The reported p-value alone cannot substitute for those details, and the direction and interpretation of a non-inferiority test depend on how the comparison and margin are specified.

What does the confidence interval show?

In general, a confidence interval gives a range of estimates compatible with the data under the statistical method used. Its width reflects precision, while its position reflects the estimate. The primary reported interval is a 97.5% confidence interval from 0.842 to 1.198 around a hazard ratio of 1.005. The interval includes 1, but the non-inferiority question requires comparison with the margin, which is not reported. The secondary analyses use reported 95% confidence intervals. Confidence levels and analysis goals should be kept distinct when reading estimates from different outcomes.

What can the reported p-values establish?

A p-value measures how unusual data at least as incompatible with a specified null model would be if that model and the test assumptions were correct. It is not the probability that the null hypothesis is true, nor does it measure clinical importance. The primary p-value is reported as < 0.001 within an analysis classified as non-inferiority. Because the margin and full testing details are absent from the registry record, the p-value cannot independently establish the non-inferiority conclusion for a reader. Secondary p-values also need to be considered alongside their confidence intervals, analysis populations, and the number of outcomes assessed.

Why can time-to-event methods be useful?

In general, time-to-event methods make use of event timing and can accommodate different follow-up durations through censoring. They are useful when not every participant has an observed event by the end of follow-up. Their interpretation depends on follow-up quality, the censoring process, and the model used to compare groups. The registry provides the outcome method and censoring description for the primary analysis, but does not report detailed model diagnostics, proportional-hazards checks, or sensitivity analyses. Those omissions limit independent assessment of the assumptions behind the reported hazard ratio.

The outcome record gives median as the parameter type, but arm-specific median values and confidence limits are null. The posted comparison therefore supports interpretation of the reported hazard ratio and interval, not a comparison of median event times. No unreported median should be inferred from the hazard ratio or from the stated follow-up period.

11. Confidence Intervals and Precision

The primary hazard ratio is 1.005, with a 97.5% confidence interval from 0.842 to 1.198. The estimate lies close to 1, while the interval spans values on either side of 1. In general, a confidence interval describes the uncertainty around an estimate under the method used; it does not guarantee that the true effect lies within that particular interval or account for bias from design or analysis limitations. The reported interval is not narrow enough to identify a single precise relative effect.

The interval includes 1, which is the no-relative-hazard-difference value for a hazard ratio. That observation is relevant to a conventional superiority interpretation, but the registry identifies the primary analysis as non-inferiority. Evaluating non-inferiority requires the margin and the appropriate confidence-bound rule. The margin is not reported in the registry record, so the interval alone cannot determine whether the study met its non-inferiority objective.

The primary confidence level is 97.5%, while the secondary comparisons are reported with 95% confidence intervals. These are not interchangeable summaries: the confidence level reflects the interval procedure and should be read alongside the analysis objective. The primary p-value is reported as < 0.001, but the registry does not give the margin or full testing specifications necessary to reconcile that value with a non-inferiority decision.

For the secondary outcomes, one reported interval does not include 1 and two include 1. Their precision and interpretation differ by endpoint, and the record does not provide absolute risks for these comparisons. A confidence interval around a hazard ratio also does not quantify the range of absolute event rates. The posted intervals should thus be treated as estimates of relative effects with uncertainty, not as direct measures of participant-level prognosis.

12. Planning a Similar Trial: Sample Size

This is a planning illustration, not a re-evaluation of the original trial. It asks: if a new study wanted to detect a difference like the one observed, or a smaller one, how large would it need to be? It is deliberately not “observed power” of the finished trial, which is not a meaningful quantity.

Effect to detect (log scale)Hazard ratioEvents, 80% powerEvents, 90% power
100% of the observed effect1.001,262,1031,689,598
75% of the observed effect1.002,243,7383,003,729
50% of the observed effect1.005,048,4106,758,389
Sample size needed versus the size of the effect to detect
Sample size needed versus size of effect to detect1,000,0002,000,0005,000,00010,000,00020,000,00040%60%80%100%80% power90% powersize of effect to detect, as % of the effect observed (log vertical scale: events required (total))
Treat these figures cautiously. The observed difference is imprecise: its confidence interval includes no difference at all. A sample size built on a noisy estimate can be far too small or too large, so the smaller-effect rows are the more cautious guide.
Method and assumptions. Two-sided α = 0.05, 1:1 allocation, Schoenfeld approximation for the log-rank test or Cox model. The answer is the total number of events, not participants; the number of participants depends on how quickly events accrue. Calculated for the comparison: Placebo vs Lorcaserin 10 mg.

The planning illustrations are based on the observed effect and are not the trial’s original design calculation. For the time-to-event comparisons, the figures are total events, not participants per arm. The assumptions listed for these illustrations are a two-sided significance level of 0.05, equal allocation between the two arms, and a normal approximation. The effect targeted is the stated fraction of the observed effect, and the event calculations use the Schoenfeld method.

The 80% power column represents the planned event total under the stated assumptions that would give an 80% chance of detecting the specified effect if that effect and the planning model were correct. The 90% column describes the corresponding event total for a 90% chance. These are planning concepts, not guarantees about what a future study will find. A smaller effect is harder to distinguish from chance variation, so the planning illustration requires more events when the target effect is smaller.

The illustration is not observed power. It does not report the probability that the completed study detected its true effect, and it should not be used as a substitute for the estimated hazard ratio and its confidence interval. The registry does not report the original sample-size justification, its target event count, or the assumptions used when the trial was designed. The planning figures are therefore best read as hypothetical illustrations under their stated assumptions, separate from the observed enrollment and results.

13. How the Sample Size Is Derived

Power is the probability that a study of a given size rejects the null hypothesis when a specific true effect exists. It depends on four things: the effect to detect, the variability of the outcome, the significance level (here a two-sided α of 0.05, so z1−α/2 = 1.960) and the desired power (z1−β = 0.842 for 80% and 1.282 for 90%).

Formula

d = 4 (z1−α/2 + z1−β)2 / [ln(HR)]2

d is the total number of events needed (Schoenfeld's formula) with 1:1 allocation and proportional hazards.

Worked calculation for this trial

  1. Hazard ratio HR = 1.005, so ln(HR) = 0.0050.
  2. d = 4 × (1.96 + 0.842)2 / [ln(1.005)]2 = 1,262,102.5, rounded up to 1,262,103 events in total for 80% power.

The smaller-effect rows in the table above repeat the same calculation with the effect multiplied by 0.75 and 0.5 (for ratios, applied to the logarithm of the ratio).

R code

alpha <- 0.05
z_a   <- qnorm(1 - alpha / 2)          # two-sided
hr <- 1.005                              # observed hazard ratio
events_needed <- function(power, frac = 1) ceiling(round(4 * (z_a + qnorm(power))^2 / log(hr^frac)^2, 6))   # Schoenfeld, 1:1 allocation
for (f in c(1, 0.75, 0.5))
  cat(sprintf("%3.0f%% of observed effect: events = %s (80%% power), %s (90%% power)\n", 100 * f,
              format(events_needed(0.80, f), big.mark = ","), format(events_needed(0.90, f), big.mark = ",")))

# Simulation: given d total events under proportional hazards, events in the treatment arm are Binomial(d, hr / (1 + hr)).
# The score (log-rank type) statistic is (D1 - d / 2) / sqrt(d / 4).
set.seed(2019264)
d    <- events_needed(0.80)
reps <- 20000
D1 <- rbinom(reps, d, hr / (1 + hr))
z  <- (D1 - d / 2) / sqrt(d / 4)
cat(sprintf("Simulated power with %s events: %.3f (%d replicates)\n", format(d, big.mark = ","), mean(abs(z) > z_a), reps))

Output from running the code

100% of observed effect: events = 1,262,103 (80% power), 1,689,598 (90% power)
 75% of observed effect: events = 2,243,738 (80% power), 3,003,729 (90% power)
 50% of observed effect: events = 5,048,410 (80% power), 6,758,389 (90% power)
Simulated power with 1,262,103 events: 0.800 (20000 replicates)

The simulation uses the fact that, with d events in total and proportional hazards, the number of events in the treatment arm is binomial. It is an approximation that conditions on the total number of events, and it should land close to the target power.

14. Analyses Reported by the Sponsor

MethodEstimate95% CIP-value
Primary Analytic MethodHazard Ratio (HR) 1.0050.842 to 1.198< 0.001

The registry reports the primary analysis as a hazard ratio of 1.005, with a 97.5% confidence interval from 0.842 to 1.198 and p < 0.001. It identifies the method as the Primary Analytic Method and classifies the analysis as non-inferiority. These are the sponsor’s reported results. The record does not state the non-inferiority margin or provide the complete decision rule.

The recalculation associated with this analysis is a simple unadjusted calculation from posted summary statistics; it is not a replacement for the sponsor’s analysis. In this case, the discrepancy indicator is false, so no disagreement between the posted sponsor result and the recalculation is flagged. The sponsor’s own analysis takes precedence as the trial’s reported inferential result.

Agreement between a recalculation and the reported estimate does not supply missing protocol details. In particular, it cannot establish the non-inferiority margin, the analysis plan, or how interim monitoring was handled. The reported p-value should remain connected to the stated non-inferiority method rather than being recast as a conventional test of difference. Interpretation of the sponsor’s conclusion requires the margin and testing details, which are not reported in the registry record.

15. Multiplicity, Missing Data and Analysis Populations

The registry reports multiple endpoints and analyses, including a primary MACE outcome and secondary outcomes spanning diabetes, mortality, renal impairment, glucose homeostasis, MACE components, and HbA1c. It identifies the primary analysis as non-inferiority and reports an interim analysis. However, the interim-analysis plan, including its timing, any monitoring boundaries, and any adjustment to the significance level, is not reported in the registry record. The primary non-inferiority margin is also not reported.

Multiplicity concerns arise when statistical tests are conducted across several outcomes or analyses. In general, the more tests that are considered, the greater the chance of an apparently notable result arising by chance if no effect exists. A prespecified hierarchy or adjustment can address this issue, but the registry record does not report whether such a procedure was used for the secondary outcomes. The relative confirmatory status of the secondary analyses is not reported either. Their p-values should therefore be interpreted cautiously and in the context of the broader set of analyses.

The primary analysis population is described as the intent-to-treat set. Events were counted on and off treatment, and participants without events were censored at their last study contact or at the visit following sponsor notification of study completion, whichever occurred first. The record does not report detailed information about missing covariate data, loss to follow-up, reasons for censoring, or sensitivity analyses addressing missing outcomes. It also does not give complete analysis-population definitions for every secondary outcome.

These gaps do not show that the analyses were inappropriate; they limit what can be independently assessed from the registry record. In general, interpretation depends on whether the analysis plan was prespecified, how interim testing was controlled, and whether missingness and censoring could be related to outcome risk. Those details are not reported in the registry record, so the posted estimates should be considered with that uncertainty in mind.

16. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

ArmParticipants with serious adverse eventsParticipants at riskPercentage
Placebo2021599233.7%
Lorcaserin 10 mg1974599532.9%
Participants with at least one serious adverse event
Serious adverse events by armPlacebo33.7%Lorcaserin 10 mg32.9%% of participants with at least one serious adverse event

Deaths

ArmDeaths (participants affected of at risk)
Placebo202 of 5992
Lorcaserin 10 mg219 of 5995

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 5% reporting threshold.

ArmParticipants affected of at risk
Placebo4788 of 5992
Lorcaserin 10 mg4946 of 5995

Most frequent serious adverse event terms

Event termOrgan systemPlaceboLorcaserin 10 mg
Angina pectorisCardiac disorders123 of 5992142 of 5995
Non-cardiac chest painGeneral disorders132 of 5992133 of 5995
Acute myocardial infarctionCardiac disorders117 of 5992105 of 5995
Angina unstableCardiac disorders106 of 5992113 of 5995
Atrial fibrillationCardiac disorders102 of 5992105 of 5995
OsteoarthritisMusculoskeletal and connective tissue disorders109 of 599293 of 5995
Cardiac failure congestiveCardiac disorders106 of 599291 of 5995
PneumoniaInfections and infestations86 of 599292 of 5995
Coronary artery diseaseCardiac disorders78 of 599287 of 5995
CellulitisInfections and infestations71 of 599248 of 5995

Most frequent non-serious adverse event terms

Event termOrgan systemPlaceboLorcaserin 10 mg
Upper respiratory tract infectionInfections and infestations567 of 5992528 of 5995
BronchitisInfections and infestations468 of 5992455 of 5995
ArthralgiaMusculoskeletal and connective tissue disorders452 of 5992457 of 5995
Back painMusculoskeletal and connective tissue disorders452 of 5992457 of 5995
DizzinessNervous system disorders340 of 5992537 of 5995
Urinary tract infectionInfections and infestations400 of 5992440 of 5995
FatigueGeneral disorders302 of 5992496 of 5995
DiarrhoeaGastrointestinal disorders324 of 5992419 of 5995
NasopharyngitisInfections and infestations338 of 5992353 of 5995
CoughRespiratory, thoracic and mediastinal disorders303 of 5992376 of 5995

Serious events with the highest arm-level rate: angina pectoris (2.4%), non-cardiac chest pain (2.2%), acute myocardial infarction (2.0%), angina unstable (1.9%), osteoarthritis (1.8%).

Do not overextend the safety comparison. Serious-adverse-event counts are safety observations, not efficacy outcomes, and should not be combined with the primary result into a single benefit-risk number.

The registry lists serious adverse-event figures for both arms, along with the number at risk for those summaries. For placebo, 2021 serious adverse events are recorded among 5992 at risk; for lorcaserin 10 mg, 1974 are recorded among 5995 at risk. The record also lists 202 deaths for placebo and 219 for lorcaserin 10 mg. These are descriptive counts, not estimates of a treatment effect, and the registry excerpt does not provide a formal comparative safety analysis for these figures.

The most frequently listed serious adverse-event terms include angina pectoris at 2.4%, non-cardiac chest pain at 2.2%, acute myocardial infarction at 2.0%, angina unstable at 1.9%, osteoarthritis at 1.8%, and cardiac failure congestive at 1.8%. The record separately reports other adverse events, with 4788 among 5992 at risk for placebo and 4946 among 5995 at risk for lorcaserin 10 mg. The relationship between event counts and the number of participants affected is not further detailed in the available description.

Counts and listed percentages should be read as registry safety summaries, not as proof that an event was caused by treatment. Differences in follow-up, event definitions, and repeated events can affect comparisons. Details of adjudication, exposure-adjusted rates, and statistical testing for safety are not reported in the registry record.

17. What the Result Does, and Does Not, Mean

The posted primary result describes the relative hazard of first MACE in the randomized comparison. The estimate is 1.005 and the 97.5% confidence interval ranges from 0.842 to 1.198. The interval includes 1 and allows for a range of relative effects. It does not demonstrate that the arms are exactly equivalent, nor does it establish a clinically meaningful benefit or harm on its own.

The registry labels the primary analysis non-inferiority and reports p < 0.001, but does not report the non-inferiority margin. Because the margin defines what degree of possible disadvantage would be considered acceptable, the reported result cannot be independently checked against that criterion from the registry record alone. The p-value should not be interpreted as proof of superiority or as a probability that the null hypothesis is true.

The hazard ratio is a relative time-to-event measure. It does not state how many participants experienced MACE, how large any absolute risk difference was, or how an individual participant would fare. The registry describes a follow-up endpoint through Month 42 and a censoring rule, but does not report the arm-specific median event times or primary event counts in the posted outcome summary. Those quantities cannot be inferred from the hazard ratio.

The secondary findings concern different outcomes and, in some cases, a subgroup defined by prediabetes at baseline. They should not be treated as interchangeable with the primary MACE result. Because a multiplicity adjustment is not reported, a secondary association—particularly one among numerous analyses—has less confirmatory weight. Safety counts likewise provide descriptive context, not a causal comparison by themselves.

Overall, the registry supports a careful account of the reported estimates and their uncertainty, but not a broad conclusion that lorcaserin is effective, ineffective, safe, or unsafe. Such claims would require the complete analysis plan, non-inferiority margin, event and absolute-risk data, and fuller safety and missing-data information, much of which is not reported in the registry record.

18. Why This Trial Matters Statistically

This trial raises several important statistical issues in a setting where both event timing and long-term follow-up matter. The primary outcome combines myocardial infarction, stroke, and cardiovascular death, and is analyzed as time to first event. That structure requires attention to censoring and to the assumptions behind time-to-event comparisons. The registry reports a Kaplan-Meier approach and Greenwood formula, but the detail available for evaluating assumptions and sensitivity analyses is limited.

The non-inferiority framework is also central to interpretation. A hazard ratio close to 1 can look reassuring at first glance, but a non-inferiority claim depends on a prespecified margin and an appropriate confidence-bound rule. The margin is not reported in the registry record. This illustrates why a point estimate and p-value cannot be interpreted apart from the design and decision criteria that define the trial’s objective.

The study also includes a broad set of secondary outcomes, including cardiometabolic and renal measures. Such outcomes can be informative, but a large collection of tests makes prespecification and multiplicity handling important. The registry’s listing of many analyses, without reporting adjustment details, means secondary results should be treated as supportive or exploratory rather than automatically confirmatory.

Finally, planning illustrations based on observed effects are distinct from the original sample-size justification and from the uncertainty in the observed treatment comparison. Separating a hypothetical planning calculation from observed evidence helps prevent mistaken claims about achieved power. Together, these considerations show why statistical interpretation depends not only on an estimate, but also on the endpoint, analysis plan, assumptions, and completeness of reporting.

19. Limitations

Several limitations are specific to the information recorded for this study. The primary analysis is classified as non-inferiority, yet the non-inferiority margin and full decision rule are not reported in the registry record. This prevents an independent reader from checking the central criterion against the reported confidence interval and p-value. The record also mentions an interim analysis without reporting its timing or statistical safeguards.

The primary outcome description gives a censoring rule and identifies the intent-to-treat set, but does not provide detailed information about loss to follow-up, reasons for censoring, or sensitivity analyses. Model diagnostics, including checks relevant to interpretation of the hazard ratio, are not reported. Arm-specific primary event counts, absolute risks, and median times are not available in the posted outcome values, limiting translation of the relative estimate into absolute terms.

Secondary outcomes vary in population and timeframe, and adjustment for multiple comparisons is not reported. Complete analysis-population and missing-data details are not given for all secondary measures. Safety summaries list event counts and selected terms, but detailed comparative analyses, exposure-adjusted rates, and adjudication information are not reported.

The registry lists enrollment of 14673, while 6000 participants are listed in each arm for the primary outcome. The record does not explain the relationship between those figures in the outcome description, so they should not be reconciled by assumption. The original sample-size justification and study-specific design assumptions are also not reported; planning illustrations based on the observed effect do not fill that gap.

20. Related Tutorials

21. Related Statistical Calculators

22. Sources

Continue through the Clinical Biostats statistical pathway

Use this trial's endpoint as a starting point for deeper study of effect measures, confidence intervals, and sample-size planning.

23. Record Summary

NCT02019264 is a completed phase 4 randomized, double-blind, placebo-controlled, parallel-group study sponsored by Eisai Inc. The registry title describes long-term BELVIQ (lorcaserin HCl) treatment and outcomes involving major adverse cardiovascular events and conversion to type 2 diabetes among overweight and obese participants with cardiovascular disease or multiple cardiovascular risk factors. Enrollment is listed as 14673. The study start date is 2014-01-24, and primary completion is listed as 2018-05-14.

The primary outcome was time from randomization to first MACE through Month 42, analyzed using Kaplan-Meier estimation and Greenwood formula. The reported hazard ratio for placebo versus lorcaserin 10 mg is 1.005, with a 97.5% confidence interval from 0.842 to 1.198 and p < 0.001. The analysis is classified as non-inferiority, but the margin is not reported in the registry record.

Secondary outcomes include diabetes, mortality, glucose homeostasis, renal impairment, MACE components, and HbA1c. The record lists 15 outcome measures and 20 analyses. The posted findings require cautious interpretation because key details about multiplicity, interim analysis, and several analysis assumptions are not reported.

Clinical Biostats