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 in Primary Care Evaluating Inclisiran Delivery Implementation + Enhanced Support (NCT04807400), a randomized phase 3 study. The primary outcome is Percentage Change in LDL-C From Baseline to Day 270.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT04807400 |
| Phase | Phase 3 |
| Condition | Atherosclerotic Cardiovascular Disease, Atherosclerotic Cardiovascular Disease Risk Equivelents, Elevated Low Density Lipoprotein Cholesterol |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 892 |
| Arms in the primary outcome | 3 |
| Lead sponsor | Novartis Pharmaceuticals |
| Results posted | Yes |
2. Clinical Question
Population
Adults with atherosclerotic cardiovascular disease (ASCVD) or ASCVD-risk equivalents and elevated LDL-C, who were on established lipid-lowering medication or had been recommended lipid-lowering therapy by a health care provider but were unable to tolerate treatment. The primary analysis used the Full Analysis Set, excluding mis-randomized participants who did not receive study drug and including only participants with LDL-C values at both baseline and Day 270.
Intervention
Inclisiran alongside background lipid-lowering therapy, delivered in an injection-only model; or inclisiran alongside background lipid-lowering therapy and behavioural support (BS). The study evaluated implementation and administration in a regional primary-care setting in the UK NHS.
Comparator
Background lipid-lowering therapy plus behavioural support, without inclisiran. The record describes this group as Control+ BS in the outcome results and Control + BS in the safety results.
Primary question
What was the percentage change in LDL-C from baseline to Day 270 in each study group, and how did each inclisiran group compare with control? The posted primary comparisons estimate a greater reduction in LDL-C for both inclisiran groups than for control. The study also examined implementation, patient-reported satisfaction, patient activation, and adherence-related measures.
The question combines a clinical biomarker outcome with a health-service implementation question. LDL-C change provides a continuous measure of change in cholesterol, while comparisons between the inclisiran delivery groups can describe whether adding behavioural support coincided with different results. The study was not a comparison of inclisiran against no background lipid-lowering care: the control group continued background therapy and received behavioural support. Accordingly, the primary contrast is between the recorded care arrangements, not between treatment and no treatment.
3. Trial Design
This was a Phase IIIb, multicentre, randomized, parallel-group study with no masking, sponsored by Novartis Pharmaceuticals. The registry title describes a study of inclisiran delivery implementation and enhanced support; the official title specifies evaluation of implementation, preference, and utility for inclisiran administration in people with ASCVD or ASCVD-risk equivalents and elevated LDL-C using primary-care models in the NHS. The registry records an enrollment of 892 and a completed status. The recorded start date is 2021-07-07, and the primary completion date is 2023-01-13.
Participants were assigned to inclisiran with background lipid-lowering therapy, inclisiran with background therapy and behavioural support, or background therapy with behavioural support. The two inclisiran groups make it possible to examine both delivery arrangements against the control care arrangement, as well as to compare the inclisiran groups with each other for selected outcomes. Because masking was recorded as none, the study was open-label. The registry record does not report the randomization sequence method, allocation concealment, or a more detailed description of how the primary-care models were implemented.
The primary outcome was percentage change in LDL-C from baseline to Day 270. The primary analysis population was described as the Full Analysis Set, comprising randomized participants except mis-randomized participants who did not receive study drug; the description also says only participants with LDL-C at baseline and Day 270 were included in the analysis. The outcome description says missing data were handled using multiple imputation with a washout model. The registry record does not report the original sample-size justification or the details needed to reconcile that imputation statement with the requirement for values at both time points.
Secondary outcomes included interviews for CFIR analysis, CSQ-8 satisfaction scores, Patient Activation Measure (PAM) scores, and measures of adherence to cardiovascular disease self-management. These broaden the study beyond the LDL-C endpoint, but the posted results do not provide numerical findings for every listed secondary measure.
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: Eligibility and recruitment to the study was optimized by using NorthWest EHealth's (NWEH) proven Feasibility Assessment and Recruitment System for Improving Trial Efficiency (FARSITE) for identification and recruitment at participating General Practitioner practices.
Overall Study
| Stage | Inclisiran | Inclisiran + BS | Control+ BS |
|---|---|---|---|
| STARTED | 298 | 297 | 297 |
| Full Analysis Set | 297 | 297 | 297 |
| Safety Set | 273 | 281 | 290 |
| COMPLETED | 248 | 252 | 234 |
| NOT COMPLETED | 50 | 45 | 63 |
Reasons for not completing this period:
| Reason | Inclisiran | Inclisiran + BS | Control+ BS |
|---|---|---|---|
| Adverse Event | 2 | 3 | 3 |
| Death | 2 | 0 | 0 |
| Lost to Follow-up | 8 | 6 | 6 |
| Non-Compliance With Study Drug | 0 | 4 | 1 |
| Participant Decision | 20 | 19 | 26 |
| Physician Decision | 0 | 1 | 0 |
| Protocol Violation | 4 | 3 | 7 |
| Withdrawal by Subject | 13 | 9 | 20 |
| Mis-randomized | 1 | 0 | 0 |
Analysis population for the primary outcome, as defined in the registry: Full analysis set. The Full Analysis Set (FAS) comprised of all randomized participants except for those mis-randomized participants who did not receive study drug. Only participants with LDL-C values at both, baseline and Day 270, were included in the analysis.
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: Baseline Participants are based on the Full Analysis Set (FAS) population, as primary and secondary analysis are based on the FAS
| Characteristic | Unit | Inclisiran | Inclisiran + BS | Control+ BS | Total |
|---|---|---|---|---|---|
| Participants analysed | 297 | 297 | 297 | 891 | |
| Age, Continuous | Years | 66.0 (SD 9.27) | 65.8 (SD 9.71) | 66.7 (SD 9.45) | 66.2 (SD 9.47) |
| Sex: Female, Male: Female | Participants | 170 | 174 | 180 | 524 |
| Sex: Female, Male: Male | Participants | 127 | 123 | 117 | 367 |
| Race/Ethnicity, Customized: Asian | Participants | 11 | 3 | 9 | 23 |
| Race/Ethnicity, Customized: Black | Participants | 1 | 0 | 5 | 6 |
| Race/Ethnicity, Customized: Mixed | Participants | 1 | 3 | 1 | 5 |
| Race/Ethnicity, Customized: White | Participants | 281 | 289 | 278 | 848 |
| Race/Ethnicity, Customized: Other | Participants | 3 | 2 | 4 | 9 |
6. Primary Endpoint
The registry lists the primary outcome as Percentage Change in LDL-C From Baseline to Day 270, measured over Baseline, Day 270.
| Element | Registry entry |
|---|---|
| Result type | Least Squares Mean |
| Measure of spread | Standard Error |
| Unit | percent change from baseline in LDL-C |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is percentage change in LDL-C from baseline to Day 270. It measures how LDL-C at the follow-up time point changed relative to baseline, expressed as a percentage. LDL-C is the biomarker named in the study’s eligibility and outcome descriptions, and change in this measure was used to compare the recorded care groups over the treatment period.
The registry reports least-squares means and standard errors for each group. The posted group estimates were -37.3 for Inclisiran, -37.6 for Inclisiran + BS, and -5.4 for Control+ BS. These are model-based mean percentage changes, not individual participants’ changes. The sponsor’s ANCOVA comparisons report estimates of -31.8 for Inclisiran versus control and -32.1 for Inclisiran + BS versus control, each with a 95% confidence interval and p < 0.001.
Using change in LDL-C makes it possible to describe the average biomarker response while retaining the size and direction of change, rather than reducing the outcome to a category such as improved or not improved. The registry’s primary description specifies that the outcome was assessed regardless of treatment discontinuation for any reason and regardless of unforeseen changes in concomitant lipid-lowering therapy. That definition is intended to retain those circumstances in the outcome framework, but the record does not provide enough detail to infer every operational feature of the estimand or model. LDL-C is a surrogate biomarker in this study; this endpoint alone does not establish effects on cardiovascular events or other clinical outcomes.
7. Results Posted in the Registry
- Inclisiran: mean -37.30 versus -5.40 on control; difference -31.90 (95% CI -38.32 to -25.48), standardized effect d = -0.80; z-test p = <0.001.
- Inclisiran + BS: mean -37.60 versus -5.40 on control; difference -32.20 (95% CI -38.67 to -25.73), standardized effect d = -0.80; z-test p = <0.001.
Mean difference: Inclisiran
95% CI: -38.32 to -25.48
Recalculated from the posted summary statistics
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 outcome | Type | Effect measure | Estimate (95% CI) | Planning size, 80% power |
|---|---|---|---|---|
| Number of Participants Interviewed for CFIR Analysis. | Binary Endpoint | Risk difference | +0.0 pts (-4.7 to 4.7) | n/a |
| Patient Reported Outcomes: CSQ-8 Total Score After Treatment | Continuous Endpoint | Mean difference | 1.40 (0.65 to 2.15) | 75 per arm |
| Patient Reported Outcomes: CSQ-8 Total Score Between Inclisiran Arms | Continuous Endpoint | Mean difference | 0.00 (-0.64 to 0.64) | n/a |
Number of Participants Interviewed for CFIR Analysis.
- Endpoint type: Binary: the number of participants with the event, compared as proportions.
- Test: Unadjusted two-proportion z-test, with a Wald 95% confidence interval for the risk difference.
- Result:
- Inclisiran + BS: 9.4% (28/297) versus 9.4% (28/297) on control; risk difference 0.0 percentage points (95% CI -4.7 to 4.7), risk ratio 1.00 (0.61–1.65); unadjusted two-proportion z-test p = 1.000.
- Interpretation:
- The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between Inclisiran + BS and the control. The interval gives the range of effects that remain compatible with the data.
Patient Reported Outcomes: CSQ-8 Total Score After Treatment
- Endpoint type: Continuous: a mean value per participant, compared as a difference in means.
- Test: Unadjusted two-sample z-test for the difference in means, using the posted standard errors.
- Result:
- Inclisiran: mean 30.10 versus 28.70 on control; difference 1.40 (95% CI 0.65 to 2.15), standardized effect d = 0.46; z-test p = <0.001.
- Inclisiran + BS: mean 30.10 versus 28.70 on control; difference 1.40 (95% CI 0.65 to 2.15), standardized effect d = 0.46; z-test p = <0.001.
- Interpretation:
- The 95% confidence interval excludes no difference, so the mean is statistically higher for Inclisiran than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.
- The 95% confidence interval excludes no difference, so the mean is statistically higher for Inclisiran + BS than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.
Patient Reported Outcomes: CSQ-8 Total Score Between Inclisiran Arms
- Endpoint type: Continuous: a mean value per participant, compared as a difference in means.
- Test: Unadjusted two-sample z-test for the difference in means, using the posted standard errors.
- Result:
- Inclisiran: mean 30.10 versus 30.10 on control; difference 0.00 (95% CI -0.64 to 0.64), standardized effect d = 0.00; z-test p = 1.000.
- Interpretation:
- The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between Inclisiran and the control. The interval gives the range of effects that remain compatible with the data.
The secondary outcomes extend the study’s focus from LDL-C change to implementation-related experience and patient-reported measures. They include interviews for CFIR analysis, CSQ-8 satisfaction scores, PAM scores, and measures of adherence to cardiovascular disease self-management. This mix reflects the study’s interest in how inclisiran is delivered in primary care as well as the primary biomarker outcome. Quantitative findings are not reported in the registry record for every listed secondary measure.
For the posted CSQ-8 analyses, the sponsor reports higher scores in each inclisiran group than in control at Day 90, with p < 0.001 for each comparison. The direct comparison between the inclisiran groups has a reported estimate of -0.03, a 95% confidence interval from -0.67 to 0.61, and p = 0.935. These results offer a secondary perspective on patient-reported satisfaction, but do not alter what the primary LDL-C endpoint measures. The interview count comparison is also posted, while PAM and adherence outcomes appear in the listed outcome descriptions without corresponding numerical results in the posted findings summarized in the registry record.
Secondary outcomes are generally interpreted more cautiously when many outcomes or comparisons are examined. Each additional test creates more opportunity for a result to appear statistically notable by chance if no adjustment or prespecified hierarchy is used. The registry record does not report a multiplicity adjustment or a testing hierarchy for these secondary outcomes. Their p-values should therefore be regarded as unadjusted evidence, not as confirmation equivalent to a single prespecified primary test. The record’s secondary findings can describe patterns and motivate further study, but they do not establish a broad effect across implementation, satisfaction, activation, and adherence domains.
The relationship between secondary and primary findings is descriptive rather than a formal mediation analysis. The registry does not report whether patient-reported experience explains any LDL-C difference, or whether the delivery model changed adherence in a way that accounts for the primary result. Such a claim would require analyses and data not reported in the registry record. The secondary outcomes are best read as complementary evidence about selected aspects of care, with their own measurement and reporting limitations.
Secondary outcomes registered for this trial, for reference (only those above were recalculated):
- Number of Participants Interviewed for CFIR Analysis.
- Patient Reported Outcomes: CSQ-8 Total Score After Treatment
- Patient Reported Outcomes: CSQ-8 Total Score Between Inclisiran Arms
- Change From Baseline to Day 90 in Total PAM Score
- Change From Baseline to Day 90 in Total PAM Score Between Inclisiran Arms
- Measures of Adherence to Cardiovascular Disease Self-management Using the Validated Patient Activation Measure (PAM) Questionnaire.
9. Statistical Interpretation
The posted primary group estimates indicate average LDL-C reductions in both inclisiran groups and a smaller average reduction in the control group. The sponsor’s ANCOVA analysis reports a between-group estimate of -31.8 for Inclisiran versus control, with a 95% confidence interval from -37.91 to -25.77 and p < 0.001. For Inclisiran + BS versus control, the estimate is -32.1, with a 95% confidence interval from -38.35 to -25.94 and p < 0.001. The estimates are expressed as differences in percentage change, so the negative direction reflects a greater reduction in the inclisiran groups relative to control.
The posted group means are close for the two inclisiran groups: -37.3 for Inclisiran and -37.6 for Inclisiran + BS. Their similarity is descriptive and does not, by itself, establish that the delivery arrangements are equivalent. The primary reported comparisons are each against control; the registry record does not report a sponsor analysis of the primary endpoint directly comparing the two inclisiran groups. The study’s reported primary findings therefore support interpretation of each inclisiran arrangement relative to the control care arrangement, not a conclusion about whether adding behavioural support changed the LDL-C result.
The registry also reports patient-reported outcomes. For CSQ-8 total score at Day 90, the posted adjusted comparisons against control are positive for both inclisiran groups, with p < 0.001 for each. The reported comparison between inclisiran arms has a value of -0.03, a 95% confidence interval from -0.67 to 0.61, and p = 0.935. This pattern is consistent with a difference from control in the reported CSQ-8 analyses, while the direct comparison between the inclisiran arms does not show a clear difference in that outcome. Such findings are secondary and should not be given the same weight as the primary endpoint, especially because the registry record does not report a multiplicity strategy.
Simple recalculations from the posted group summaries give mean differences of -31.9 and -32.2 for the two inclisiran-versus-control primary comparisons, with confidence intervals that are close to the sponsor’s ANCOVA results. These recalculations are unadjusted approximations, not substitutes for the sponsor’s analysis. Their agreement in broad direction and scale provides a useful consistency check, while the sponsor’s model-based estimates remain the primary reported results.
These results describe the outcomes measured in this randomized study and the analyses recorded in the registry. They do not establish that the observed differences apply to settings, populations, or care arrangements beyond those studied. Nor does a biomarker result alone answer questions about cardiovascular events, long-term outcomes, or individual experience. The registry does not report enough detail about several design and analysis decisions to resolve those questions or to assess all potential sources of uncertainty.
10. Statistical Methods Explained
The primary outcome is continuous: it is a percentage change in LDL-C, rather than a yes-or-no event. The registry reports least-squares means for the study groups. A least-squares mean is a model-based group mean, estimated within the analysis model. It can differ from a simple arithmetic average when the model accounts for other variables or features of the analysis. The registry identifies ANCOVA as the sponsor’s primary comparison method, but the full model specification and covariates are not reported in the registry record.
What does an ANCOVA comparison describe?
ANCOVA, or analysis of covariance, compares groups using a model that can account for specified covariates. For a change-from-baseline endpoint, such models can estimate adjusted group results while taking baseline values into account. The registry reports the method and the least-squares mean contrasts, but does not identify the covariates or provide the full model. It is therefore possible to describe the reported estimates and uncertainty, but not to reconstruct the sponsor’s exact analysis from the registry record.
The primary sponsor comparisons are reported as superiority analyses. A superiority analysis tests whether the estimated outcome differs between groups in the direction assessed by the model. The reported p-values are p < 0.001 for both comparisons against control. A p-value describes how compatible the observed data are with the statistical null model used for that test; it is not the probability that the null hypothesis is true, and it does not measure the clinical importance of an estimate. Interpretation should therefore consider the effect estimate and confidence interval, not the p-value alone.
Why are confidence intervals useful?
A confidence interval gives a range of estimates compatible with the data and the analysis assumptions at the stated confidence level. The sponsor reports 95% confidence intervals for the primary comparisons. For Inclisiran versus control, the interval is -37.91 to -25.77; for Inclisiran + BS versus control, it is -38.35 to -25.94. Both intervals lie on the negative side of zero, in keeping with the reported direction of the comparison and the p-values. An interval is not a guarantee that the true effect lies within its endpoints. Its interpretation depends on the model, the data, and the assumptions used to produce it.
The posted summaries also permit simple unadjusted recalculations of mean differences and approximate confidence intervals. These use the reported group estimates and standard errors rather than the sponsor’s full ANCOVA model. For the primary comparisons, the recalculated estimates are -31.9 and -32.2. The calculations use an approximate pooled standard deviation inferred from the standard errors and sample sizes, as identified in the statistical summaries. Because this is an approximation and does not reproduce the sponsor’s adjusted model, it is best treated as a check on broad consistency rather than a competing primary result. The registry does not flag a discrepancy between the sponsor analyses and the recalculations.
What is the role of standard error?
A standard error describes the precision of an estimated mean under the analysis assumptions. Smaller standard errors generally correspond to less sampling uncertainty in the estimated mean, while larger standard errors correspond to more. It is not the same as the spread of individual participant outcomes. The primary group summaries report standard errors of 2.29, 2.33, and 2.34 for the respective groups. These values describe uncertainty around group means, not the range of individual LDL-C changes.
The registry describes multiple imputation using a washout model for missing data. Multiple imputation is a general method that fills in missing values across repeated datasets, reflecting uncertainty about the missing observations rather than treating a single filled-in value as known. A washout model is the stated approach for imputing missing data in this outcome. The exact imputation model, variables included, number of imputations, and diagnostic checks are not reported in the registry record. There is also a wording tension: the population description says only participants with values at baseline and Day 270 were included, while the outcome description says missing data were imputed. Without further details, the precise relationship between these statements cannot be determined.
Why can over-dispersion matter?
General statistical explanation: over-dispersion occurs when the observed variability is greater than a model expects. If a model underestimates variability, standard errors can be too small and confidence intervals too narrow; if the model accommodates the additional variability, uncertainty may be more appropriately represented. The registry does not report an over-dispersion assessment or indicate that over-dispersion was a concern for the primary continuous outcome. This general point should not be read as a claim that over-dispersion occurred in this study.
Randomization supports comparisons between the assigned groups, but it does not remove uncertainty from finite samples or guarantee that every aspect of care was identical apart from the assigned arrangement. The study was unmasked, and the primary care models included behavioural support in the control group and in one inclisiran group. The registry record does not report allocation concealment details, adherence to assigned arrangements, or a complete account of co-interventions. Those details matter when interpreting what aspect of care a between-group contrast represents.
11. Confidence Intervals and Precision
The sponsor reports 95% confidence intervals for the primary comparisons. The interval for Inclisiran versus control runs from -37.91 to -25.77 around an estimate of -31.8. The interval for Inclisiran + BS versus control runs from -38.35 to -25.94 around an estimate of -32.1. Both intervals indicate uncertainty around the estimated difference, but each is entirely on the negative side of zero. In the sponsor’s ANCOVA analyses, this is consistent with p < 0.001 for both comparisons.
Confidence intervals communicate both direction and precision. An interval that covers a broad range allows more possible values for the underlying contrast than a narrower interval, while an interval’s location indicates which directions of effect are compatible with the analysis. The intervals do not make the estimate exact; they show that the observed comparisons remain estimates with sampling uncertainty. They also do not account automatically for every possible limitation, such as missing data, model misspecification, or selective reporting.
The recalculated unadjusted intervals are similar in broad location and scale: -38.32 to -25.48 for Inclisiran versus control, and -38.67 to -25.73 for Inclisiran + BS versus control. These are approximate intervals based on posted summary statistics, not the sponsor’s adjusted ANCOVA intervals. Their similarity is reassuring as a check that the posted group summaries and reported primary comparisons point in a consistent direction, but the methods differ and the recalculation should not replace the sponsor’s reported analysis.
Precision should also be distinguished from importance. A precise estimate may still be limited to the outcome and population studied, and a statistically clear contrast does not establish its implications for other clinical outcomes. The registry record does not report a threshold for a clinically important LDL-C difference, so the confidence intervals cannot be judged against such a threshold using this record alone.
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 | Participants per arm, 80% power | Participants per arm, 90% power |
|---|---|---|
| 100% of the observed effect | 25 | 33 |
| 75% of the observed effect | 44 | 58 |
| 50% of the observed effect | 98 | 130 |
The sample-size illustrations use the observed effect as a starting point and show planning numbers for detecting the stated fraction of that effect. For the reported continuous outcomes, the numbers are participants per arm, not total participants across the study. 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 the stated fraction of the observed effect. These are planning illustrations computed from observed results; they are not the original trial design assumptions, which are not reported in the registry record.
The 80% power column gives the participants per arm for a design with an 80% chance of detecting the specified effect under the stated assumptions, if that effect and the model assumptions were true. The 90% power column gives the participants per arm for a design with a 90% chance under those same assumptions. Neither column describes how likely the trial’s observed result was to be true, nor does it show the probability that an individual participant would have a particular outcome.
Rows planning for 100% of the observed effect use the full observed estimate as the target; rows planning for 75% or 50% use smaller target effects. Smaller effects need more participants to detect than larger effects, all else equal, which is why the planning counts rise as the assumed fraction falls. The primary-outcome illustrations report 25 participants per arm for 80% power and 33 participants per arm for 90% power when planning for 100% of the observed effect; the counts increase for the smaller-effect assumptions.
This is not observed power. Observed results and their confidence intervals describe the data more directly; a post-result power calculation based on the observed effect does not add independent evidence. The planning values are conditional illustrations, not a statement about the trial’s actual design rationale or a recommended sample size for another study. Different assumptions, populations, outcome variability, or analysis methods could lead to different planning counts.
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
n is the number of participants in each arm, Δ is the difference in means to detect and σ is the common standard deviation.
Worked calculation for this trial
- Observed difference Δ = -31.900; pooled standard deviation σ = 39.661.
- n = 2 × (1.96 + 0.842)2 × 39.6612 / -31.9002 = 24.3, rounded up to 25 participants per arm 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
delta <- -31.9 # observed difference in means
sigma <- 39.6611221248861 # pooled standard deviation
n_per_arm <- function(power, frac = 1) {
ceiling(round(2 * (z_a + qnorm(power))^2 * sigma^2 / (delta * frac)^2, 6))
}
for (f in c(1, 0.75, 0.5))
cat(sprintf("%3.0f%% of observed effect: n per arm = %s (80%% power), %s (90%% power)\n", 100 * f,
format(n_per_arm(0.80, f), big.mark = ","), format(n_per_arm(0.90, f), big.mark = ",")))
# Check against R's built-in function (t-based, so very slightly larger)
cat("power.t.test:", round(power.t.test(delta = delta, sd = sigma, power = 0.80)$n, 1), "\n")
# Simulation: exact two-sample t-test using simulated means and variances
set.seed(4807400)
n <- n_per_arm(0.80)
reps <- 20000
m_diff <- rnorm(reps, delta, sigma * sqrt(2 / n)) # difference in sample means
s2 <- sigma^2 * rchisq(reps, 2 * (n - 1)) / (2 * (n - 1)) # pooled sample variance
tstat <- m_diff / sqrt(s2 * 2 / n)
cat(sprintf("Simulated power at n = %s per arm: %.3f (%d replicates)\n", format(n, big.mark = ","), mean(abs(tstat) > qt(0.975, 2 * (n - 1))), reps))
Output from running the code
100% of observed effect: n per arm = 25 (80% power), 33 (90% power)
75% of observed effect: n per arm = 44 (80% power), 58 (90% power)
50% of observed effect: n per arm = 98 (80% power), 130 (90% power)
power.t.test: 25.3
Simulated power at n = 25 per arm: 0.797 (20000 replicates)
The simulation draws many sets of group means and variances at the planned sample size and counts how often the two-sample t-test rejects the null. It should land close to the target power; at very small required sample sizes it can fall below it, because the normal approximation is rough there.
14. Analyses Reported by the Sponsor
| Method | Estimate | 95% CI | P-value |
|---|---|---|---|
| ANCOVA | Least Squares Mean -31.8 | -37.91 to -25.77 | < 0.001 |
| ANCOVA | Least Squares Mean -32.1 | -38.35 to -25.94 | < 0.001 |
The registry reports the sponsor’s primary comparisons using ANCOVA and least-squares mean differences. Inclisiran versus control is reported as -31.8, with a 95% confidence interval from -37.91 to -25.77 and p < 0.001. Inclisiran + BS versus control is reported as -32.1, with a 95% confidence interval from -38.35 to -25.94 and p < 0.001. These are the primary reported analyses and should anchor interpretation of the primary endpoint.
The recalculated comparisons use the posted group summaries to form simple unadjusted estimates. They produce -31.9 for Inclisiran versus control and -32.2 for Inclisiran + BS versus control, with approximate confidence intervals. The estimates are close to the sponsor’s reported values, but the recalculations do not reproduce ANCOVA adjustment and rely on approximate dispersion derived from the summary statistics. They are therefore useful as an independent arithmetic consistency check, not as a replacement analysis.
The registry record does not flag a discrepancy between the sponsor’s results and the recalculations. The agreement in the direction and approximate magnitude supports the reading that the primary conclusions are not an artifact of a simple arithmetic mismatch in the posted summaries. It does not establish that all model assumptions are satisfied, resolve missing-data questions, or address endpoints beyond the primary comparison. The sponsor’s own ANCOVA analysis remains the relevant reported analysis for the primary endpoint.
15. Multiplicity, Missing Data and Analysis Populations
The registry record reports a primary endpoint and several secondary outcomes, but does not report a multiplicity strategy. When researchers test many outcomes or comparisons, the chance of at least one apparently notable result can increase. Statistical approaches such as adjustment, a prespecified hierarchy, or clearly designated exploratory analyses can help readers understand how confirmatory the findings are. Since such an approach is not reported in the registry record, the primary endpoint should be distinguished from secondary results, and secondary p-values should be treated as unadjusted.
The primary outcome description states that missing LDL-C data were imputed using a washout model. Multiple imputation is a general approach that represents uncertainty about missing values across multiple completed datasets. However, the same outcome description says that only participants with LDL-C values at both baseline and Day 270 were included in the analysis. The registry record does not explain how these statements fit together, which participants contributed imputed values, or whether any analyses used a different population. The imputation model details, assumptions about why values were missing, and sensitivity analyses are not reported in the registry record.
The Full Analysis Set is described as all randomized participants except those mis-randomized participants who did not receive study drug. The primary endpoint description further narrows the analyzed group to participants with LDL-C at both specified time points. The record therefore gives a population definition, but does not provide a flow of participants by analysis or explain how exclusions and missing data affected each comparison. The enrollment figure is 892, while the primary group summaries report their own analysis sample sizes; the registry does not provide enough detail to reconcile all populations and denominators.
Other analysis details are also not reported in the registry record, including the complete ANCOVA specification, covariates, treatment of protocol deviations, and whether any interim analyses took place. The registry record does not report the original sample-size justification or the assumptions underlying that design decision. The planning illustrations are based on observed effects and should not be mistaken for those original assumptions. These omissions limit how fully an independent reader can assess prespecification, analysis robustness, and the consequences of missing data.
16. 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 |
|---|---|---|---|
| Inclisiran | 24 | 273 | 8.8% |
| Inclisiran + BS | 36 | 281 | 12.8% |
| Control + BS | 28 | 290 | 9.7% |
| Total | 88 | 844 | 10.4% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Inclisiran | 2 of 273 |
| Inclisiran + BS | 0 of 281 |
| Control + BS | 0 of 290 |
| Total | 2 of 844 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Inclisiran | 3 of 273 |
| Inclisiran + BS | 2 of 281 |
| Control + BS | 0 of 290 |
| Total | 5 of 844 |
Most frequent serious adverse event terms
| Event term | Organ system | Inclisiran | Inclisiran + BS | Control + BS | Total |
|---|---|---|---|---|---|
| Atrial fibrillation | Cardiac disorders | 2 of 273 | 5 of 281 | 0 of 290 | 7 of 844 |
| Pneumonia | Infections and infestations | 4 of 273 | 1 of 281 | 1 of 290 | 6 of 844 |
| Type 2 diabetes mellitus | Metabolism and nutrition disorders | 3 of 273 | 1 of 281 | 2 of 290 | 6 of 844 |
| Acute myocardial infarction | Cardiac disorders | 1 of 273 | 1 of 281 | 2 of 290 | 4 of 844 |
| Acute kidney injury | Renal and urinary disorders | 2 of 273 | 2 of 281 | 0 of 290 | 4 of 844 |
| Urinary tract infection | Infections and infestations | 1 of 273 | 2 of 281 | 0 of 290 | 3 of 844 |
| Urosepsis | Infections and infestations | 1 of 273 | 2 of 281 | 0 of 290 | 3 of 844 |
| Suicidal ideation | Psychiatric disorders | 2 of 273 | 0 of 281 | 1 of 290 | 3 of 844 |
| Angina unstable | Cardiac disorders | 1 of 273 | 1 of 281 | 0 of 290 | 2 of 844 |
| Cardiac failure | Cardiac disorders | 1 of 273 | 1 of 281 | 0 of 290 | 2 of 844 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Inclisiran | Inclisiran + BS | Control + BS | Total |
|---|---|---|---|---|---|
| Injection site rash | General disorders | 1 of 273 | 0 of 281 | 0 of 290 | 1 of 844 |
| Back pain | Musculoskeletal and connective tissue disorders | 1 of 273 | 0 of 281 | 0 of 290 | 1 of 844 |
| Muscle spasms | Musculoskeletal and connective tissue disorders | 1 of 273 | 0 of 281 | 0 of 290 | 1 of 844 |
| Pain in extremity | Musculoskeletal and connective tissue disorders | 1 of 273 | 0 of 281 | 0 of 290 | 1 of 844 |
| Dizziness | Nervous system disorders | 0 of 273 | 1 of 281 | 0 of 290 | 1 of 844 |
| Rash | Skin and subcutaneous tissue disorders | 0 of 273 | 1 of 281 | 0 of 290 | 1 of 844 |
Serious events with the highest arm-level rate: atrial fibrillation (1.8%), pneumonia (1.5%), type 2 diabetes mellitus (1.1%), suicidal ideation (0.7%), acute kidney injury (0.7%).
The registry reports serious adverse events for participants at risk in each group. Serious adverse events affected 24 of 273 participants at risk in Inclisiran, 36 of 281 in Inclisiran + BS, and 28 of 290 in Control + BS. Across the reported safety population, 88 of 844 participants at risk were affected. The registry also reports deaths: 2 in Inclisiran and 0 in each of the other groups.
These are descriptive counts and denominators from the safety record. They should not be treated as a causal comparison or interpreted as proof that one care arrangement is safer than another. The record does not provide the detail needed to assess event timing, duration of exposure, adjudication, or adjustment for differences in follow-up. It also does not report inferential comparisons for these safety figures. The number of participants at risk is not necessarily the same as the number in the primary efficacy analysis, and the registry record does not provide a full accounting of why denominators differ across outcomes.
The registry lists atrial fibrillation at 1.8%, pneumonia at 1.5%, and type 2 diabetes mellitus at 1.1% among the top serious-event terms, followed by suicidal ideation and acute kidney injury at 0.7% each, and diverticulitis at 0.7%. These terms provide a description of events recorded as serious; they do not by themselves establish that the study treatment caused them. Safety interpretation should remain limited to the reported counts and terms.
17. What the Result Does, and Does Not, Mean
The primary result describes a difference in average LDL-C percentage change at Day 270 between the recorded care arrangements. The sponsor’s ANCOVA estimates favor a larger reduction in the two inclisiran groups than in the control group, and both reported primary comparisons have confidence intervals that remain on the negative side of zero. This is evidence about the biomarker outcome under the study’s analysis, not a direct estimate of cardiovascular events or other long-term clinical outcomes.
The study also compares distinct delivery arrangements. One inclisiran group received background lipid-lowering therapy and inclisiran in an injection-only model; the other also received behavioural support. The control group received background therapy plus behavioural support. The primary analyses compare each inclisiran group with control, so they do not isolate the effect of behavioural support from the effect of adding inclisiran. The registry does not report a primary endpoint comparison between the two inclisiran groups.
The statistical evidence does not resolve every question about implementation. The study was open-label, and the registry does not report the detailed methods used to deliver behavioural support, participant adherence to assigned arrangements, or the full analysis model. The stated missing-data handling and analysis population descriptions also leave uncertainty about the precise set of observations analyzed. These details affect how confidently the results can be generalized or attributed to a particular component of care.
Nor should a statistically clear result be treated as a judgment about individual benefit or as medical advice. Group averages do not describe every participant, and the registry record does not report a threshold for a clinically important change in LDL-C. Patient-reported findings provide additional, secondary information but do not establish that satisfaction or implementation outcomes caused the primary biomarker difference. The results are most appropriately understood as evidence about the measured outcomes in this trial, with the stated uncertainty and registry reporting limitations.
18. Why This Trial Matters Statistically
Statistically, this study is notable for setting a biomarker comparison within a primary-care implementation question. The randomized parallel design compares inclisiran delivery arrangements alongside background lipid-lowering care, including a control arrangement with behavioural support. That structure makes the treatment contrast more specific than a comparison with no background care, while also making clear that the primary comparisons do not isolate every feature of the delivery model.
The primary results are supported by both the sponsor’s ANCOVA analyses and simple recalculations from the posted summaries. The two approaches yield similar estimates in direction and broad scale, but they are not interchangeable: the sponsor’s analysis is model-based, whereas the recalculations are unadjusted approximations. This distinction is useful for statistical literacy because it separates a transparent check of summary arithmetic from the trial’s reported inferential analysis.
The confidence intervals contribute more than a thresholded p-value alone. They show the range of values compatible with the reported analysis and help readers assess the precision of the estimated contrasts. At the same time, their interpretation depends on the model and data handling, and the registry leaves important details about covariates, missing data, and analysis populations unresolved. Statistical significance cannot compensate for those reporting gaps.
Finally, the combination of LDL-C, satisfaction, interview, activation, and adherence outcomes highlights the challenge of interpreting a study with several outcome domains. The primary endpoint has a distinct role; the secondary outcomes add context but carry more uncertainty when multiplicity handling is not reported and some numerical results are absent. This makes the study a useful example of separating a primary statistical conclusion from broader implementation questions that require fuller outcome reporting.
19. 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 trial was unmasked, so participants and study personnel could know the assigned care arrangement. This can matter particularly for experience and satisfaction outcomes, which may be influenced by expectations or by awareness of treatment. The registry record does not report measures to limit or evaluate such influence. The study was multicentre and set in a regional primary-care context in the UK NHS, so the registry description alone does not establish how closely other health systems or care settings match the studied arrangement.
The primary endpoint is a biomarker outcome. The registry record does not report cardiovascular event results as the primary outcome, and the LDL-C change should not be interpreted as a direct measure of clinical events. The record also does not report a clinically important difference threshold for the endpoint, which limits interpretation of the practical importance of the estimated differences.
Several analysis details are not reported in the registry record: the full ANCOVA model and covariates, randomization and allocation concealment procedures, interim analyses, original sample-size justification, multiplicity handling, and detailed missing-data assumptions. The stated imputation approach and the stated restriction to participants with measurements at both time points are not reconciled. These gaps limit independent assessment of analysis robustness and the influence of missingness.
Secondary outcome reporting is incomplete in the registry record. Although PAM and adherence-related measures are listed, numerical results are not available for every listed outcome. The secondary p-values that are reported are not accompanied by a reported multiplicity strategy. Safety information is presented as counts and event terms, without enough detail to establish causal attribution or compare risk over time. These limitations do not negate the reported estimates, but they constrain how broadly and confidently they can be interpreted.
20. Related Tutorials
21. Related Statistical Calculators
22. Sources
- ClinicalTrials.gov: Study in Primary Care Evaluating Inclisiran Delivery Implementation + Enhanced Support — NCT04807400.
- Registry record last updated 2024-10-09; status last verified 2024-10.
- Results first posted 2024-03-25.
- 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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23. Record Summary
NCT04807400 is a completed, Phase IIIb, randomized, open-label, parallel-group study sponsored by Novartis Pharmaceuticals. It enrolled 892 participants and evaluated inclisiran delivery in a regional UK NHS primary-care setting for people with ASCVD or ASCVD-risk equivalents and elevated LDL-C. The primary endpoint was percentage change in LDL-C from baseline to Day 270.
The sponsor reported ANCOVA comparisons showing greater LDL-C reduction for Inclisiran and Inclisiran + BS than for Control+ BS, with p < 0.001 for both comparisons. Recalculated unadjusted estimates are similar in broad direction and scale. Secondary findings include CSQ-8 comparisons and an interview count, while numerical results are not reported for every listed secondary outcome. Registry safety results include serious adverse event counts and deaths by group.
Important details—including the original sample-size justification, multiplicity strategy, full model specification, and resolution of the missing-data wording—are not reported in the registry record. The results should therefore be read as estimates for the stated outcomes and study arrangements, with uncertainty about some analysis details and without inferring effects on unreported clinical outcomes.