Study of Rapastinel as Monotherapy in Patients With MDD: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Study of Rapastinel as Monotherapy in Patients With MDD (NCT03560518), a randomized phase 3 study. The primary outcome is Change From Baseline on Montgomery-Asberg Depression Rating Scale (MADRS) Total Score at End of Treatment (End of Week 6).

2. Clinical Question

The MADRS measures depressive symptoms, with lower scores indicating fewer symptoms. The registry defines a negative change from baseline as improvement. Accordingly, the between-group mean difference is interpreted in relation to the direction and size of the average changes, as well as its uncertainty. A difference near zero would indicate similar average changes in the compared groups; a confidence interval spanning zero is compatible with effects in either direction.

The study also posted a secondary outcome measuring MADRS change from baseline to Day 1 after the first dose. That outcome addresses a different time point from the primary Week 6 endpoint. The registry record does not report a formal analysis for either outcome, so the numerical comparisons discussed are unadjusted recalculations from posted group summaries rather than sponsor-reported inferential results.

3. Trial Design

This was a phase 3, randomized, double-blind, parallel-group, placebo-controlled study of rapastinel monotherapy in patients with major depressive disorder. Its official title describes it as multicenter. The registry lists 439 participants enrolled and identifies Naurex, Inc, an affiliate of Allergan plc, as the sponsor. The record gives a start date of 2018-06-15 and a primary completion date of 2019-07-08. Its status is terminated; the reason for termination is not reported in the registry record.

Participants were assigned to placebo, rapastinel 450 mg, or rapastinel 900 mg. Each was administered weekly by intravenous infusion, with the active treatment described as posted in a prefilled syringe. The double-blind description indicates that masking was part of the design, but the registry record does not give further details about how masking was maintained or assessed.

The primary endpoint was change in MADRS total score from baseline to the end of Week 6. Group results are reported as means and standard deviations. The specified primary analysis population is the modified Intent-to-Treat population, defined as patients in the Safety Population who had at least one postbaseline assessment of MADRS total score or S-STS total score. The record does not report the trial’s original statistical analysis plan, the reason for selecting that population, or the protocol assumptions used to plan enrollment.

The study is marked terminated, but that status alone does not explain why it ended or whether the planned study activities were completed as intended. The registry record does not report a termination explanation. It also lists no reported analyses for the posted outcomes, limiting what can be concluded about sponsor-conducted modeling, adjustment, or inferential procedures.

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.

Double Blind Treatment Period

Reasons for not completing this period:

Safety Follow-Up Period

Analysis population for the primary outcome, as defined in the registry: The modified Intent-to-Treat (mITT) Population will consist of all patients in the Safety Population who had at least 1 postbaseline assessment of the MADRS total score or S-STS total score.

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 modified Intent-to-Treat (mITT) Population will consist of all patients in the Safety Population who had at least 1 postbaseline assessment of the MADRS total score or S-STS total score.

6. Primary Endpoint

The registry lists the primary outcome as Change From Baseline on Montgomery-Asberg Depression Rating Scale (MADRS) Total Score at End of Treatment (End of Week 6), measured over Baseline to end of Week 6.

The primary endpoint is change from baseline in Montgomery–Åsberg Depression Rating Scale (MADRS) total score at the end of treatment, defined as the end of Week 6. The MADRS is a clinician-rated measure of depressive symptoms over the preceding week. It covers ten symptom items, including sadness, lassitude, pessimism, inner tension, suicidality, sleep or appetite reduction, difficulty concentrating, and lack of interest. Each item is rated on a seven-point scale, and the total score ranges from 0 to 60; a higher total indicates more depression. The registry specifies that a negative change score indicates improvement.

Change from baseline describes how the group’s average score at follow-up differs from its baseline score. Comparing those changes across randomized groups is intended to distinguish the pattern over time in each group from the pattern observed with placebo. The mean is useful for expressing the average change, while the standard deviation describes variation among individual outcome values within a group. Neither measure by itself describes every participant’s experience.

A clinician-rated symptom scale offers a structured way to assess change in the symptom domain the study set out to examine. However, the endpoint is a measured score, not a direct account of all aspects of a participant’s health or functioning. Interpretation also depends on the between-group comparison and its precision, not only on whether each group’s mean change is negative. The registry record does not report a threshold for a clinically meaningful difference or additional details supporting the choice of the Week 6 time point.

7. Results Posted in the Registry

• Rapastinel 450mg: mean -13.20 versus -13.80 on control; difference 0.60 (95% CI -2.11 to 3.31), standardized effect d = 0.05; z-test p = 0.664.
• Rapastinel 900mg: mean -11.30 versus -13.80 on control; difference 2.50 (95% CI -0.17 to 5.17), standardized effect d = 0.21; z-test p = 0.066.

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.

Change From Baseline in MADRS Total Score at Day 1 Post-first Dose of 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 deviations.
• Result:
  • Rapastinel 450mg: mean -9.00 versus -11.00 on control; difference 2.00 (95% CI -0.15 to 4.15), standardized effect d = 0.21; z-test p = 0.068.
  • Rapastinel 900mg: mean -8.30 versus -11.00 on control; difference 2.70 (95% CI 0.65 to 4.75), standardized effect d = 0.30; z-test p = 0.010.
• Interpretation:
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between Rapastinel 450mg and the control. The interval gives the range of effects that remain compatible with the data.
  • The 95% confidence interval excludes no difference, so the mean is statistically higher for Rapastinel 900mg than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.

The registry posts one secondary outcome: change in MADRS total score from baseline to Day 1 after the first dose. It uses the same scale and direction convention as the primary endpoint, but its assessment time is much earlier than the end-of-Week-6 primary time point. That makes it useful as a separate description of the early measurement pattern, not as a replacement for the primary endpoint.

Across the secondary comparisons, both active-treatment groups had mean changes that were less negative than placebo. The recalculated unadjusted intervals do not give the same pattern of uncertainty for both dose comparisons: one includes zero, while the other does not. This differs from the primary endpoint, where both recalculated intervals include zero. The secondary pattern therefore is not a uniform confirmation of the primary comparisons; it is time-point-specific and should be interpreted cautiously.

The registry record does not report sponsor analyses for this secondary outcome. The comparisons are recalculated from posted group summaries, and the p-values are unadjusted. When several outcomes, doses, or time points are examined, the chance of at least one apparently unusual result can increase unless the analysis plan addresses multiplicity. The record does not describe such a procedure. For that reason, an unadjusted secondary result generally carries less weight than a prespecified primary result, especially when it differs in pattern from the primary endpoint.

The Day 1 measurement also does not, by itself, establish the persistence, clinical importance, or cause of a difference at that time. It is one outcome at one assessment point. The record does not report a hierarchy for secondary outcomes, a multiplicity adjustment, or a detailed analysis plan that would clarify how this measure was intended to support the primary question.

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

• Change From Baseline in MADRS Total Score at Day 1 Post-first Dose of Treatment

9. Statistical Interpretation

10. Statistical Methods Explained

The primary outcome is continuous: each participant’s MADRS change is a numerical score, and the registry reports group means and standard deviations. A mean gives the arithmetic average of the measured changes in a group. A standard deviation describes how dispersed those individual measurements are around the mean. It is not the uncertainty of the mean itself: uncertainty in a group mean also depends on the amount of information in that group.

What does the mean difference represent?

The comparison is expressed as the active-treatment mean change minus the placebo mean change. Since a negative change is defined as improvement, a positive between-group difference means that the active group’s average change is less negative than the placebo group’s average change. A negative difference would point in the opposite direction. This sign convention matters: “positive” does not mean a positive change from baseline, and it does not by itself describe whether either group improved.

For the primary outcome, the posted summaries yield recalculated unadjusted mean differences of 0.6 for rapastinel 450 mg and 2.5 for rapastinel 900 mg. These are simple comparisons of group summaries, not estimates adjusted for other variables. The registry record does not report a sponsor analysis for these outcomes, so the recalculated estimates should not be confused with results from a documented prespecified model.

Why consider the standard deviation?

Variation affects how precisely a group mean and a between-group difference can be estimated. When outcome values vary widely, the mean may be less precisely estimated for a given amount of information. In the posted primary results, the group standard deviations are around 11 points, while the estimated between-group differences are smaller. That contrast helps explain why an estimate can have a direction and a numerical size but still be uncertain. It does not mean that all individual results were similar or that the scale has a particular clinical interpretation beyond what the registry states.

Over-dispersion is a general concern in statistical modeling when the observed variation exceeds what a model assumes. For a continuous outcome, the direct issue is whether the model represents the outcome distribution and its variability adequately. The posted results include group standard deviations, but the registry record does not report diagnostic checks, distributional assumptions for a sponsor model, or a model-based analysis. It is therefore not possible to assess those matters from the record.

How should a confidence interval be read?

In general, a confidence interval describes the range of effect sizes reasonably compatible with the observed data under the method used to construct it. A narrower interval indicates greater precision; a wider interval indicates more uncertainty. For a difference in means, zero represents no estimated difference. An interval that crosses zero includes both the possibility of no difference and values on either side of it. It is not a probability statement that the true value lies within the particular interval.

The recalculated primary intervals include zero for both dose comparisons. They therefore do not establish a direction of difference with high precision. The interval for 450 mg extends from -2.11 to 3.31. For 900 mg, the lower endpoint is below zero and the upper endpoint is 5.168. The latter endpoint is written as reported in the registry-derived comparison; the exact lower endpoint is not repeated because it has more than three decimal places. The central interpretation is that each interval spans zero.

What does an unadjusted p-value say?

In general, a p-value describes how unusual data at least as discrepant as those observed would be under a specified null model. It does not give the probability that the null hypothesis is true, and it does not quantify the probability that a result occurred “by chance.” The primary unadjusted p-values are 0.664 and 0.066. They are tied to the recalculated comparisons and do not address the consequences of considering more than one dose or outcome. The registry record does not report a multiplicity procedure or the sponsor’s test model.

For continuous data, the spread of observations and the amount of information jointly influence the uncertainty of a mean difference. The comparisons use the posted arm means, standard deviations, and group sizes in simple unadjusted recalculations. No covariate adjustment, repeated-measures model, imputation approach, or other modeling detail is reported for the primary endpoint. The registry’s outcome population definition is available, but the record does not explain how missing assessments were handled within that population.

The distinction between a recalculation and a trial analysis is important. A recalculation can provide a transparent reading of the posted summaries, but it cannot reproduce unreported details such as the original analysis set, data handling, model specification, or adjustment strategy. The registry record reports no outcome analyses. Consequently, these inferential summaries should be read as unadjusted statistical descriptions based on the posted group results, rather than as a substitute for a complete sponsor analysis.

11. Confidence Intervals and Precision

Precision concerns how much uncertainty surrounds an estimated difference. For the primary Week 6 comparisons, the recalculated 95% confidence interval for rapastinel 450 mg versus placebo runs from -2.11 to 3.31. For rapastinel 900 mg versus placebo, its lower endpoint is below zero and its upper endpoint is 5.168. Both intervals include zero, so the posted summaries are compatible with no difference as well as with differences in either direction.

The point estimates are 0.6 for the 450 mg comparison and 2.5 for the 900 mg comparison. The point estimate alone does not show how precisely the difference is known; the confidence interval supplies that context. The intervals leave considerable uncertainty about the size and direction of the population difference. The 450 mg interval includes negative and positive values, and the 900 mg interval does too. A confidence interval is not a range containing a stated proportion of individual participants’ outcomes, nor does it show how each participant responded.

The unadjusted p-values, 0.664 and 0.066, also reflect the evidence against a zero difference under the recalculation’s assumptions. They should not be read as probabilities that rapastinel has no effect. Since the registry record does not report sponsor analyses or multiplicity handling, the intervals and p-values are best treated as unadjusted summaries rather than definitive adjusted inference.

The registry does not state a threshold for a clinically important MADRS difference. It is therefore not possible to determine from the record whether any particular value within either interval would be clinically important. The intervals primarily show that the estimated differences are not precise enough to pin down a narrow range of plausible between-group effects.

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.

The sample-size table and curve are planning illustrations based on observed effect estimates, not descriptions of the trial’s original design. The figures are participants per arm for these continuous-outcome comparisons; they are not total event counts. The stated planning assumptions are a two-sided significance level of 0.05, equal allocation between the two arms, and a normal approximation. Each planning row uses the stated fraction of the observed effect as the effect to detect. The registry record does not report the trial’s own original sample-size assumptions or justification.

The 80% power column gives the illustrative number of participants per arm associated with an 80% chance of detecting the specified effect under those assumptions, if that effect is the true one and the model assumptions hold. The 90% column gives the analogous planning target for 90% power. Power is a design property tied to an assumed effect and analysis procedure; it is not a measure of how likely a result already observed is true.

Rows using a smaller fraction of the observed effect represent smaller target differences. Smaller effects are harder to distinguish from random variation and therefore require more participants per arm under the same assumptions. The curve expresses this same relationship across effect sizes, while the table gives selected planning scenarios. For example, the 900 mg primary comparison lists 341 participants per arm for 80% power when planning for 100% of the observed effect, and 1,363 when planning for 50% of it. These are hypothetical planning figures, not observed enrollment recommendations for this trial.

This is not observed power. The calculations are illustrations based on the observed estimates, and they do not establish whether the trial was adequately planned or whether the original investigators used these assumptions.

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 z_1−α/2 = 1.960) and the desired power (z_1−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

1. Observed difference Δ = 0.600; pooled standard deviation σ = 11.777.
2. n = 2 × (1.96 + 0.842)² × 11.777² / 0.600² = 6,048.0, rounded up to 6,048 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 <- 0.600000000000001                      # observed difference in means
sigma <- 11.7770963721256                     # 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(3560518)
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 = 6,048 (80% power), 8,097 (90% power)
 75% of observed effect: n per arm = 10,752 (80% power), 14,394 (90% power)
 50% of observed effect: n per arm = 24,192 (80% power), 32,387 (90% power)
power.t.test: 6049 
Simulated power at n = 6,048 per arm: 0.801 (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. Multiplicity, Missing Data and Analysis Populations

Multiplicity arises when statistical conclusions are drawn from more than one comparison or outcome. This study has two active-dose comparisons against placebo for the primary endpoint, and the registry also posts a secondary MADRS outcome with two active-dose comparisons. Considering multiple tests can increase the chance that at least one result appears noteworthy even if there is no underlying difference. A prespecified testing order, adjusted significance threshold, or other multiplicity procedure can address that issue, but the registry record does not report whether one was used.

The posted p-values are unadjusted recalculations. They should not be treated as if they account for the number of comparisons. The record lists no reported analyses, so it does not establish whether the sponsor used a different inferential approach or how any family of tests was defined. Without that information, the posted inferential summaries cannot establish which outcomes, if any, met a prespecified confirmatory criterion.

Missing data are another important issue for change-from-baseline outcomes. The primary population definition requires at least one postbaseline MADRS or S-STS assessment among patients in the Safety Population. That definition does not explain how incomplete follow-up was handled, whether all observed measurements were used, or how missing endpoint values were treated. Imputation methods, sensitivity analyses, and the amount or pattern of missing outcome data are not reported in the registry record.

The group sizes attached to the primary endpoint summaries and the at-risk counts in the safety results are not identical in every arm. Those are reported in their respective outcome contexts, and the registry record does not explain the differences. They should not be assumed to represent the same analysis population. The absence of analysis details limits assessment of possible bias from exclusions, missing measurements, or differences between the population used for each outcome and the randomized groups.

15. Safety Results

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

Deaths

Other (non-serious) adverse events

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

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: abortion induced (0.7%), asphyxia (0.7%), anaemia (0.7%), depression (0.7%), haemorrhoidal haemorrhage (0.7%).

The registry reports serious adverse event affected counts of 2 in the placebo group, 2 with rapastinel 450 mg, and 1 with rapastinel 900 mg. The corresponding at-risk counts are 147, 145, and 147. These are counts of participants affected, not a rate comparison recalculated for this interpretation. No deaths were reported in the placebo group, 1 was reported in the 450 mg group, and none in the 900 mg group.

These counts should be read as descriptive safety information. A small number of events cannot by itself establish whether groups differ reliably, and the record does not provide a statistical comparison for serious adverse events. It also does not report details such as exposure-adjusted rates, event timing, adjudication, or the relationship of each event to treatment. The at-risk counts identify the group denominators for these safety summaries; they should not be substituted for the primary outcome group sizes.

The registry also reports counts of participants affected by other adverse events, but those are distinct from serious adverse events. The serious-event figures do not summarize all safety outcomes or establish causation.

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

The primary endpoint results describe average MADRS change through the end of Week 6 in the registry’s specified analysis population. Mean changes were negative in all groups, and the recalculated differences between each rapastinel dose and placebo were positive. Because negative change indicates improvement, those positive differences mean the active-group average changes were less negative than the placebo average changes in the posted summaries.

Both primary confidence intervals include zero, and the recalculated p-values are unadjusted. The results therefore leave uncertainty about whether the groups differed and about the size and direction of any population difference. They do not demonstrate equivalence, since the registry record does not state an equivalence margin or report an equivalence analysis. Nor do these summaries establish that a difference of a particular size would be clinically important; the record does not give a clinical-importance threshold.

Group averages also do not describe each participant’s outcome. The standard deviations show variation within each group, and the mean alone cannot identify how many participants improved, stayed similar, or worsened. The registry record does not provide a distribution of individual changes in the registry record reported for this analysis.

The Day 1 secondary outcome gives an earlier and separate view of MADRS change. Its pattern is not uniform across dose comparisons and does not remove the uncertainty in the primary Week 6 comparisons. Since the secondary p-values are unadjusted and multiplicity handling is not reported, they should not be treated as independent confirmation of a treatment effect.

The appropriate reading is limited to what these posted data can support: descriptive group changes and uncertain, unadjusted between-group estimates. The record does not report sponsor analyses, missing-data methods, or the reasons for trial termination, so the summaries cannot answer every question about the study’s conduct or the robustness of its conclusions.

17. Why This Trial Matters Statistically

This trial illustrates why within-group change and between-group comparison answer different questions. Each group’s mean MADRS score changed in the negative direction, but the randomized comparison asks whether the average change differed between each rapastinel group and placebo. The primary estimates are small relative to the observed variability, and their confidence intervals include zero. Reading the group means alone would miss that uncertainty.

It also shows why estimates should be read alongside precision. A point estimate is one summary of the data, while a confidence interval indicates how broadly the data are compatible with different effects. Here, the primary comparisons do not tightly establish the direction of a difference. The unadjusted p-values add another description of the comparisons but cannot substitute for interval interpretation or account for multiplicity that is not documented in the registry record.

The study’s secondary endpoint further illustrates the distinction between a result at an early time point and the primary result at the end of Week 6. Different assessment times can yield different patterns, and an unadjusted secondary finding should not be treated as decisive evidence when the analysis hierarchy and multiplicity strategy are unreported.

Finally, the registry distinguishes the outcome population from safety reporting and provides no reported sponsor analyses. Those details matter statistically: analysis populations, missing-data handling, and prespecified modeling can affect interpretation. Planning illustrations based on observed effects are also not substitutes for the original design assumptions. Together, these features make the study a useful example of interpreting reported summaries without overstating what they establish.

18. 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.

Several trial-specific limitations constrain interpretation. The registry marks the study terminated but does not report the reason. It gives no sponsor-conducted analyses for the posted outcomes, so the available comparisons are recalculations from arm-level summaries rather than a documented analysis under the trial’s original statistical plan. The model, covariate adjustment, and inferential procedures used by the sponsor are not reported.

The registry defines the primary analysis population, but does not report how missing outcome measurements were handled, the extent or pattern of missingness, or sensitivity analyses. Those omissions make it difficult to assess how incomplete follow-up may have affected the estimates. The record also does not explain why the primary endpoint group sizes and the safety at-risk counts differ in some arms; those counts should be interpreted within their separate outcome contexts.

Multiplicity procedures are not reported despite the presence of two active doses and a posted secondary outcome. The recalculated p-values are unadjusted, so they should not be read as confirmatory results that account for all comparisons. The registry record also does not specify a clinically meaningful MADRS difference, limiting interpretation of the practical importance of values within the confidence intervals.

Finally, the primary endpoint is a clinician-rated symptom scale at a single stated end-of-treatment time point. The record does not provide additional primary follow-up outcomes or details about longer-term results in the registry record reported for this analysis. These limitations do not change the reported means and uncertainty, but they restrict the broader conclusions that can be drawn from them.

19. Related Tutorials

20. Related Statistical Calculators

21. Sources

• ClinicalTrials.gov: Study of Rapastinel as Monotherapy in Patients With MDD — NCT03560518.
• Registry record last updated 2020-09-01; status last verified 2020-08.
• Results first posted 2020-09-01.
• 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.

22. Record Summary

NCT03560518 is a phase 3 randomized, double-blind, parallel-group, placebo-controlled, multicenter study of rapastinel monotherapy in patients with major depressive disorder. The registry lists 439 participants enrolled and names Naurex, Inc, an affiliate of Allergan plc, as sponsor. The record gives a start date of 2018-06-15, a primary completion date of 2019-07-08, and a terminated status; the reason for termination is not reported.

The primary outcome was change in MADRS total score from baseline to the end of Week 6. Posted arm means were -13.8 for placebo, -13.2 for rapastinel 450 mg, and -11.3 for rapastinel 900 mg. Recalculated unadjusted comparisons have confidence intervals that include zero for both doses. The registry also posts a Day 1 secondary MADRS outcome, with no reported sponsor analyses. Safety summaries include serious adverse event affected counts of 2, 2, and 1 across placebo, 450 mg, and 900 mg, respectively, and death counts of 0, 1, and 0.