To Compare the Safety and Efficacy of Perrigo's Product to an FDA Approved Product for the Treatment of Secondarily Infected Traumatic Skin Lesions: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for To Compare the Safety and Efficacy of Perrigo's Product to an FDA Approved Product for the Treatment of Secondarily Infected Traumatic Skin Lesions (NCT04155203), a randomized phase 3 study. The primary outcome is Proportion of Subjects in Each Treatment Group With Clinical Cure (Defined as a Skin Infection Rating Scale (SIRS) Score of 0 for All Signs and Symptoms).

2. Clinical Question

The trial asked whether participants treated with Perrigo’s mupirocin cream had a different proportion of clinical cures from participants treated with a reference manufacturer’s mupirocin cream, and how each active-treatment group compared with vehicle control. The primary outcome defined cure as a Skin Infection Rating Scale (SIRS) score of 0 for all signs and symptoms at 18 days. The registry record describes the trial as a comparison of safety and efficacy in secondarily infected traumatic skin lesions.

The posted results list 145.0 participants with cure in the Perrigo active group, 169.0 in the reference active group, and 124.0 in the vehicle control group. The corresponding listed group sizes are 160.0, 181.0, and 168.0. These group-level counts and the comparative estimates describe the posted primary outcome; the registry record does not provide additional outcome time points or secondary outcome measures.

3. Trial Design

This was a Phase 3, randomized, double-blind, multicenter, vehicle-controlled, parallel-group study. The trial record identifies three groups: Perrigo active, reference active, and vehicle control. Both active groups are listed as mupirocin calcium. The study’s stated purpose was to compare Perrigo’s product with a reference manufacturer’s product and to compare both active treatments with vehicle for secondarily infected traumatic skin lesions.

The registry lists enrollment as 657 and status as completed. The recorded start date is 2019-10-15, and primary completion is recorded as 2021-06-01. The posted primary outcome is a count of participants meeting the clinical-cure definition at 18 days. The group listings give sizes of 160.0 for Perrigo active, 181.0 for reference active, and 168.0 for vehicle control; the corresponding cure counts are 145.0, 169.0, and 124.0.

Randomization and double masking are stated, but operational details are not reported in the registry record. This includes the randomization sequence method, allocation concealment, which roles were masked, and how masking was maintained. The record does not report the number or locations of study centers, treatment dose or schedule, or the length of treatment. It also does not describe participant flow from enrollment through outcome assessment, or explain the relationship between the overall enrollment figure and the group sizes listed with the primary outcome.

The group comparisons are presented against reference active treatment: Perrigo active versus reference active, and vehicle control versus reference active. The posted comparative estimates are unadjusted recalculations from the summary counts. The registry also includes a sponsor-reported equivalence analysis for Perrigo active versus reference active. The analysis method for that result is not reported, so it should be read as a distinct reported analysis rather than assumed to be interchangeable with the recalculated risk difference.

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.

Overall Study

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.

6. Primary Endpoint

The registry lists the primary outcome as Proportion of Subjects in Each Treatment Group With Clinical Cure (Defined as a Skin Infection Rating Scale (SIRS) Score of 0 for All Signs and Symptoms), measured over 18 days.

The primary endpoint is the proportion of participants in each treatment group with clinical cure at 18 days. Cure is defined as a Skin Infection Rating Scale (SIRS) score of 0 for all signs and symptoms. The endpoint is binary at the participant level: each participant either meets that stated definition or does not. The registry records the outcome as a count of participants, with a group size also listed for each treatment arm.

A clinical-cure endpoint gives a direct summary of how many participants met the prespecified clinical definition at the stated assessment time. Comparing proportions across randomized groups can describe differences in the frequency of that outcome. The risk difference expresses the absolute difference in proportions, while risk ratios and odds ratios express the comparison on relative scales. These measures answer related but distinct questions, and their interpretation depends on the endpoint definition and the groups being compared.

The definition is specific to a score of 0 for all signs and symptoms; the registry record does not describe individual SIRS components, scoring procedures, assessor training, or rules for handling an assessment that is unavailable. It also does not report a separate definition of treatment failure or a longer-term assessment. The posted endpoint therefore describes clinical status at 18 days under the stated definition, rather than a broader measure of sustained recovery or other outcomes.

7. Results Posted in the Registry

• Perrigo Active: 90.6% (145/160) versus 93.4% (169/181) on control; risk difference -2.7 percentage points (95% CI -8.5 to 3.0), risk ratio 0.97 (0.91–1.03); unadjusted two-proportion z-test p = 0.349.
• Vehicle Control: 73.8% (124/168) versus 93.4% (169/181) on control; risk difference -19.6 percentage points (95% CI -27.1 to -12.0), risk ratio 0.79 (0.72–0.87); unadjusted two-proportion z-test p = <0.001.

8. Statistical Interpretation

9. Statistical Methods Explained

The posted primary outcome is binary: a participant either meets the clinical-cure definition at 18 days or does not. The registry provides group sizes and counts meeting the definition, alongside a set of comparative estimates. The following explanations are general statistical interpretation; they do not fill in analysis details that are not reported in the registry record.

What does a risk difference describe?

A risk difference subtracts the event proportion in one group from the event proportion in the comparison group, with the direction determined by the stated comparison. Here, the Perrigo active and vehicle comparisons are each expressed relative to reference active. A negative estimate means the event proportion in the named group is lower than in the reference group for this ordering. The risk difference is an absolute contrast, expressed on the proportion scale. Its interval describes uncertainty about the contrast, subject to the method used to construct it. The method and interval level for the recalculated estimates are not reported in the registry record.

For Perrigo active versus reference active, the recalculated risk difference is -0.027 and its interval extends from -0.085 to 0.030. Since zero lies within that interval, the result does not rule out no difference on the risk-difference scale. For vehicle control versus reference active, the estimate is -0.196 and the interval extends from -0.271 to -0.120; zero is outside that interval. These statements describe the intervals as posted and do not establish that any particular treatment is clinically preferable.

How do risk ratios and odds ratios differ?

A risk ratio compares the event proportions by division, while an odds ratio compares the odds of the event. Both are relative measures, but an odds ratio is not the same quantity as a risk ratio. For either ratio, the no-difference value is 1. The Perrigo-to-reference intervals include 1 for both the reported risk ratio and odds ratio. The vehicle-to-reference intervals are below 1 for both measures. The risk difference may be easier to interpret as an absolute separation in event proportions, whereas relative measures describe proportional contrasts. The registry’s recalculations are unadjusted comparisons from posted summary statistics; no adjusted model is specified.

What does a p-value contribute?

A p-value describes how incompatible the observed data are with a particular null hypothesis under the assumptions of the statistical test. It does not measure the probability that the null hypothesis is true, the size of an effect, or the probability that a result will recur. The posted unadjusted p-value is 0.349 for Perrigo active versus reference active and <0.001 for vehicle versus reference active. The test method is not reported in the registry record. The p-values should be considered alongside the effect estimates and their intervals, rather than used as a substitute for them.

A non-significant result is not proof of equivalence. Equivalence requires a prespecified margin defining what differences are small enough to count as equivalent, together with an analysis designed to assess that margin. The registry reports a sponsor equivalence analysis for the active-treatment comparison, but does not report its method or the equivalence margin. The recalculated risk-difference interval is a separate, unadjusted summary and cannot supply those missing design details.

Why might allocation and masking matter?

Random allocation is intended, in general, to balance prognostic factors across groups on average and to support a causal interpretation of group contrasts. Double masking is generally intended to reduce the influence of expectations on participant experiences, clinical assessments, or study conduct. Those are general reasons for these design features; the registry’s labels alone do not describe how randomization or masking was implemented. Details such as sequence generation, concealment, masked roles, and success of masking are not reported in the registry record.

What analysis details remain important?

Interpretation also depends on the population included in each analysis, missing outcome handling, protocol deviations, and whether the analysis followed a prespecified plan. The record does not report these details for the primary endpoint. It lists one primary outcome measure and one analysis, and no posted secondary outcome measures. Those listings do not establish that no other analyses were performed or that a particular analysis population was used. The record does not state whether the reported comparisons were adjusted for other variables or whether any multiplicity procedure was used.

Because the endpoint is a count of participants meeting a binary definition, an analysis of proportions is appropriate in general. If data were clustered by study center or otherwise dependent, methods accounting for that dependence could matter, but the registry does not provide information to assess this. No center-adjusted analysis is reported. Similarly, missing outcome status can affect an observed proportion if the availability of assessments differs across groups; the record does not state the extent of missingness or the method used to address it. These are general considerations, not claims about what occurred in this trial.

10. Confidence Intervals and Precision

An interval estimate communicates a range of values compatible with the data and the method used to construct it. It is not a guarantee that the true value lies inside the interval, and it does not describe the range of individual participant outcomes. A wider interval indicates less precision about the comparative effect; a narrower interval indicates greater precision, all else equal. The confidence level for the recalculated intervals is not reported in the registry record, so it should not be inferred.

For Perrigo active versus reference active, the risk-difference estimate is -0.027 and the interval runs from -0.085 to 0.030. The interval includes zero, so the posted data are compatible with no difference as well as with a difference in either direction on this scale. The risk-ratio interval, 0.911 to 1.034, and odds-ratio interval, 0.311 to 1.514, include 1, their no-difference value. The point estimates alone should not be read as precise determinations of the comparative effect.

For vehicle control versus reference active, the risk-difference interval runs from -0.271 to -0.120. The interval is entirely negative. The risk-ratio interval, 0.717 to 0.872, and odds-ratio interval, 0.102 to 0.395, are entirely below 1. These intervals show the direction and uncertainty of the posted unadjusted comparisons; they do not address unreported sources of bias or missing data.

The sponsor-reported active-treatment equivalence result has a 90% interval from -8.19 to 2.70 around an equivalence ratio of 0.97. Because the registry record does not describe the calculation method or clarify the scale of those limits, the interval cannot be interpreted confidently alongside the recalculated risk-difference interval. Precision is therefore best assessed separately for each reported measure, while recognizing the limits in the record’s methodological detail.

11. 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 planning figures are expressed as participants per arm, not as total events. They are illustrations based on the observed effect in each comparison, not a report of the trial’s original sample-size calculation. The planning 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 set at the stated fraction of the observed effect. The trial’s own original design assumptions are not reported in the registry record.

The 80% power column gives the number of participants per arm that the planning calculation estimates would be needed to have an 80% chance of detecting the selected effect under those assumptions. The 90% power column gives the corresponding number per arm for a higher chance of detecting that effect. These are planning targets conditional on the assumed effect and calculation method; they are not guarantees about a future study’s results.

For the Perrigo active versus reference active comparison, the planning display gives 1,533 participants per arm for 80% power and 2,051 for 90% power when planning for 100% of the observed effect. For 75% of the observed effect, the figures are 2,618 and 3,505; for 50% of the observed effect, they are 5,649 and 7,562. For vehicle control versus reference active, the corresponding figures are 56 and 74 for 100% of the observed effect, 87 and 116 for 75%, and 167 and 222 for 50%.

Smaller effects require more participants to detect under these assumptions, which is why the displayed planning numbers increase as the chosen fraction of the observed effect decreases. These figures are planning illustrations, not observed power. They should not be interpreted as evidence that the completed trial had a particular probability of finding a difference, nor as a reconstruction of the sponsor’s original design calculation.

12. 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, p₀ and p₁ are the control and treatment proportions, and p̄ is their average.

Worked calculation for this trial

1. Control proportion p₀ = 0.934; treatment proportion p₁ = 0.906; average p̄ = 0.920.
2. First term: z_1−α/2 × √[2p̄(1−p̄)] = 1.96 × 0.3837 = 0.7521.
3. Second term: z_1−β × √[p₀(1−p₀) + p₁(1−p₁)] = 0.842 × 0.3832 = 0.3225.
4. n = (0.7521 + 0.3225)² / (-0.0275)² = 1,532.4, rounded up to 1,533 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
p0 <- 0.933701657458563                          # control proportion
p1 <- 0.90625                          # treatment proportion
n_per_arm <- function(power, frac = 1) {
  q1 <- p0 + (p1 - p0) * frac               # smaller effect = fraction of the observed difference
  pbar <- (p0 + q1) / 2
  z_b <- qnorm(power)
  ceiling(round((z_a * sqrt(2 * pbar * (1 - pbar)) + z_b * sqrt(p0 * (1 - p0) + q1 * (1 - q1)))^2 / (q1 - p0)^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 (unrounded n per arm)
cat("power.prop.test:", round(power.prop.test(p1 = p0, p2 = p1, power = 0.80)$n, 1), "\n")

# Simulation: how often does the z-test reject at the 80%-power sample size?
set.seed(4155203)
n    <- n_per_arm(0.80)
reps <- 20000
x0 <- rbinom(reps, n, p0); x1 <- rbinom(reps, n, p1)
ph <- (x0 + x1) / (2 * n)
z  <- ((x1 - x0) / n) / sqrt(ph * (1 - ph) * 2 / n)
cat(sprintf("Simulated power at n = %s per arm: %.3f (%d replicates)\n", format(n, big.mark = ","), mean(abs(z) > z_a, na.rm = TRUE), reps))

Output from running the code

100% of observed effect: n per arm = 1,533 (80% power), 2,051 (90% power)
 75% of observed effect: n per arm = 2,618 (80% power), 3,505 (90% power)
 50% of observed effect: n per arm = 5,649 (80% power), 7,562 (90% power)
power.prop.test: 1532.4 
Simulated power at n = 1,533 per arm: 0.802 (20000 replicates)

The simulation draws many pairs of event counts at the planned sample size and counts how often the two-proportion z-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.

13. Analyses Reported by the Sponsor

The registry reports a sponsor analysis for Perrigo active versus reference active labeled as an equivalence analysis. It gives an equivalence ratio of 0.97 and a 90% interval from -8.19 to 2.70. A method, equivalence margin, and explanation of the interval scale are not reported in the registry record. Without those details, the result cannot be fully interpreted or directly translated into the risk-difference scale.

The recalculated comparison uses the posted group counts and gives a risk difference of -0.027, with an interval from -0.085 to 0.030 and an unadjusted p-value of 0.349. It is an unadjusted re-calculation from summary statistics, not the sponsor’s analysis. It addresses whether the observed group proportions differ on the risk-difference scale, whereas an equivalence analysis asks whether the difference is sufficiently bounded within a prespecified margin. The registry does not state that margin or the sponsor’s analysis method.

The two results should therefore be reported as separate analyses rather than treated as competing estimates of an identical quantity. The recalculated interval includes zero, but that finding alone does not establish equivalence. The sponsor’s stated equivalence result cannot be independently assessed from the registry record’s methodological information. No discrepancy is flagged between the posted summary and the recalculation.

14. Multiplicity, Missing Data and Analysis Populations

Multiplicity arises when several outcomes, comparisons, time points, or analyses are tested: the more opportunities there are to find a nominally unusual result, the more important it can be to interpret the testing plan and any adjustment. That is a general statistical consideration, not evidence that a particular multiplicity issue occurred in this trial. The registry lists one primary outcome measure and one analysis, and no posted secondary outcome measures. It does not report whether other outcomes or analyses were conducted, whether the two active-versus-reference and vehicle-versus-reference comparisons were jointly treated as a family, or whether any multiplicity adjustment was planned or applied.

The primary outcome is a count of participants meeting a binary clinical-cure definition. The record does not report the analysis population used for the primary comparison, such as whether all randomized participants were included or whether a different population was used. It also does not report an intention-to-treat designation, a per-protocol analysis, or how exclusions after randomization were handled. The randomized design is stated, but the analysis population cannot be inferred from that design label alone.

Missing data handling is not reported in the registry record. The number of participants without an evaluable outcome, the reasons for missing assessments, and the approach to missing outcome status are not stated. For a binary endpoint, assumptions about unavailable outcomes can influence the estimated group proportions; the extent and direction of any such influence cannot be assessed without those details.

The record also does not describe protocol deviations, adherence, prespecified analysis plans, covariate adjustment, interim analyses, or sensitivity analyses. Those items should not be assumed to have occurred or not occurred. The posted values permit an unadjusted comparison of the summary counts, but do not reveal the full analysis plan or establish whether all reported analyses were prespecified.

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

Serious events with the highest arm-level rate: cellulitis (0.5%).

The serious adverse event listings report 0 affected participants in Perrigo active, 1 in reference active, and 0 in vehicle control. Each group is listed with 219 participants at risk for serious adverse events. The record also lists 0 deaths in each group. These are counts from the registry record and should be read as reported, without combining groups or treating the at-risk figures as the primary-outcome group sizes.

For other adverse events, the registry lists 0 affected participants in each group, with 219 at risk in each. The serious adverse event term identified as a leading term is cellulitis, listed as 0.5%. The denominator and the details behind that percentage are not reported in the registry record. No further event-level description, severity breakdown, timing, or attribution detail is included in the registry entries.

These counts describe reported events; they do not by themselves establish whether an event was caused by treatment. A zero count in a group does not establish that an event is impossible, and a count in one group does not establish a comparative safety difference. The registry record does not report the methods used for safety surveillance or the criteria applied to classify events.

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

The posted primary results describe clinical cure at 18 days using the registry’s definition: a SIRS score of 0 for all signs and symptoms. The recalculated Perrigo-versus-reference risk difference is -0.027, with an interval from -0.085 to 0.030 and an unadjusted p-value of 0.349. The interval includes zero, so the summary comparison does not provide a clear distinction between the groups on the risk-difference scale. This is not proof that the treatments are equivalent or that their effects are identical.

The vehicle-versus-reference comparison has a risk difference of -0.196, with an interval from -0.271 to -0.120 and an unadjusted p-value of <0.001. The posted group proportions and relative measures also show a lower observed cure proportion for vehicle than for reference active. These are unadjusted comparisons based on the posted summary counts. Their interpretation is limited by the absence of reported details about missing outcomes, analysis populations, adjustment, and the statistical methods used to construct the intervals.

The sponsor-reported equivalence analysis is a separate result. The registry gives an equivalence ratio of 0.97 and a 90% interval from -8.19 to 2.70, but does not report the method, equivalence margin, or scale interpretation needed to assess it fully. The recalculated risk difference should not be used as a substitute for those missing equivalence details.

The record supports a description of the trial design, endpoint, posted group counts, comparative estimates, and serious adverse event counts. It does not establish the effects of treatment beyond the assessed outcome and timeframe, explain how the results might generalize to people or settings not described in the record, or resolve unreported design and analysis questions. The serious adverse event counts likewise describe reported counts and do not, on their own, establish causation or a comparative safety conclusion.

17. Why This Trial Matters Statistically

This trial offers a useful example of why statistical interpretation should keep endpoint definition, effect scale, and analysis question aligned. The primary outcome is a binary clinical-cure measure at 18 days. A risk difference describes an absolute contrast in proportions, while risk ratios and odds ratios express relative contrasts. Even when all these measures refer to the same group summaries, they answer different questions and should not be conflated.

The active-treatment comparison illustrates the distinction between finding no clear difference and establishing equivalence. The recalculated risk-difference interval includes zero, and its unadjusted p-value is 0.349. That does not establish that the treatments are sufficiently similar under an equivalence criterion. Equivalence requires a defined margin and a suitable analysis; the registry’s sponsor-reported equivalence result lacks the method and margin needed for a full independent interpretation.

The vehicle comparison illustrates how an effect estimate and its interval contribute information beyond a p-value. The recalculated risk-difference interval is entirely below zero, while the reported risk-ratio and odds-ratio intervals are below 1. These measures all describe the posted vehicle-versus-reference comparison, but they do not replace consideration of the endpoint, assessment time, analysis population, and possible missing data.

The record also shows the importance of distinguishing planning calculations from observed trial results. Sample-size illustrations based on fractions of the observed effect can help readers understand how assumptions about the target effect influence required enrollment. They do not recover the trial’s original design assumptions, and they are not observed power. Clear separation of these questions helps prevent a planning calculation or a non-significant result from being given a stronger interpretation than it supports.

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 details needed for fuller appraisal are not reported in the registry record. These include eligibility criteria beyond the stated condition, participant baseline characteristics, study-center count and locations, product dose and schedule, treatment duration, and the operational details of randomization and double masking. The trial is described as multicenter, randomized, and double-blind, but those labels do not supply implementation details.

The primary outcome is defined and has an assessment timeframe of 18 days, but the record does not describe individual SIRS components, assessment procedures, assessor training, or handling of unavailable assessments. It does not report participant flow, attrition, the number of missing primary outcomes, or the primary analysis population. The relationship between the enrollment figure of 657 and the group sizes listed for the outcome is not explained in the registry record.

The recalculated estimates are unadjusted. The record does not report the method used to construct their intervals, the intervals’ confidence level, or whether estimates adjusted for study center or other characteristics were also produced. The sponsor’s equivalence analysis is reported without a method or equivalence margin, and the scale of its interval limits is not clarified. The multiplicity approach and the handling of multiple comparisons are also not reported.

Safety information is limited to the listed serious and other adverse-event counts, deaths, and a leading serious-event term. Event timing, severity details, attribution, and the denominator underlying the cellulitis percentage are not reported. These omissions limit how much can be inferred about the broader safety profile or the robustness and generalizability of the efficacy comparisons.

19. Related Tutorials

20. Related Statistical Calculators

21. Sources

• ClinicalTrials.gov: To Compare the Safety and Efficacy of Perrigo's Product to an FDA Approved Product for the Treatment of Secondarily Infected Traumatic Skin Lesions — NCT04155203.
• Registry record last updated 2022-11-03; status last verified 2022-10.
• Results first posted 2022-11-03.
• 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

The registry record describes a completed, randomized, double-blind, multicenter, parallel-group Phase 3 trial of Perrigo active treatment, reference active treatment, and vehicle control for secondarily infected traumatic skin lesions. Enrollment is listed as 657; the recorded start date is 2019-10-15, and primary completion is 2021-06-01.

The primary outcome was clinical cure at 18 days, defined as a SIRS score of 0 for all signs and symptoms. The posted recalculated comparison for Perrigo active versus reference active has a risk difference of -0.027, with an interval from -0.085 to 0.030 and an unadjusted p-value of 0.349. The vehicle-versus-reference estimate is -0.196, with an interval from -0.271 to -0.120 and an unadjusted p-value of <0.001.

A sponsor-reported equivalence analysis is also listed for the active-treatment comparison, but its method and equivalence margin are not reported. Serious adverse event counts are 0, 1, and 0 across Perrigo active, reference active, and vehicle control, respectively; the record lists 0 deaths in each group.