Study Evaluating the Safety and Effects of MN-221 in Subjects With Moderate to Severe Asthma: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Study Evaluating the Safety and Effects of MN-221 in Subjects With Moderate to Severe Asthma (NCT00679263), a randomized phase 2 study. The primary outcome is Number of Patients Reported to Have Adverse Events.

2. Clinical Question

3. Trial Design

This is a randomized, single-blind, parallel-group, placebo-controlled phase 2 study of MN-221 in subjects with moderate to severe asthma. The registry describes a dose rate escalation study and identifies two active-treatment arms: MN-221 1-hour infusion and MN-221 2-hour infusion. A placebo intravenous infusion was the control. The placebo description states that its dosing volume was equivalent to active treatment. The registry does not report the specific dosing rates, dose levels, escalation sequence, or details of how participants moved through or were assigned to those levels.

The study is listed as completed. Its start is recorded as 2008-02 and its primary completion as 2008-07. Enrollment is listed as 17. However, the primary outcome entries give arm counts of 11, 6, and 11. The registry record does not explain why those arm counts do not correspond to the stated enrollment, whether the counts refer to a different population, or whether any participants were represented in more than one entry. The discrepancy makes the denominators difficult to interpret and should not be resolved by assumption.

Randomization can reduce systematic differences between groups when implemented and preserved, while a parallel-group design assigns participants to separate treatment groups for comparison. Single-blind indicates that some party was masked, but the registry does not identify who was blinded or describe masking procedures. The record also does not report sequence generation, allocation concealment, treatment adherence, withdrawals, or the planned analysis population. These missing design details limit assessment of how the study was conducted and how directly the posted results represent randomized comparisons.

The study lists a secondary outcome, change from baseline in FEV1 percent predicted. The registry record does not provide its result in the registry record for interpretation. Consequently, the posted information supports description of the design and adverse-event counts, but not an assessment of whether MN-221 changed lung function or how any such change compared with placebo.

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: Subjects were screened for eligibility and must have demonstrated an improvement in forced expiratory volume in 1 second (FEV1) of at least 12% and 200 cc at the Screen Visit after bronchodilator treatment compared to pre-bronchodilator use. Continued eligibility was determined for each subject prior to administering each dose.

Visit 3/Dose 2

Visit 2/Dose 1

Reasons for not completing this period:

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 Number of Patients Reported to Have Adverse Events, measured over Day 1 to Day 2.

The primary endpoint is titled Number of Patients Reported to Have Adverse Events, uses participants as its unit, and covers Day 1 to Day 2. It is a count of participants reported as having an adverse event during the stated timeframe. Unlike an event total, a participant count does not distinguish someone with one event from someone with multiple events. The title therefore points to how many people were affected, rather than how many separate events occurred.

Safety outcomes are used in trials to describe undesirable events observed during treatment and to compare their reporting across groups. Counts can be informative, especially in a small study, but their interpretation depends on clear denominators, consistent definitions, and complete follow-up. A count alone does not establish whether an event was caused by treatment. Nor does it convey event severity, duration, timing within the observation window, or clinical importance unless those details are reported separately.

For this endpoint, the posted values are 11 in the MN-221 1-hour infusion arm, 6 in the placebo arm, and 11 in the MN-221 2-hour infusion arm. The outcome entries do not provide uncertainty estimates or a statistical comparison. The separate adverse-event record lists other adverse events affecting 11, 4, and 9 participants in those respective arms. The record does not explain the difference between the primary-outcome figures and the separate other-adverse-event counts. Therefore, the primary endpoint should be read as its own reported set of counts, not silently reconciled with the other safety entries.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

Statistical interpretation begins by identifying the outcome, the comparison, and the population to which the result applies. In this study, the primary outcome is a participant count for adverse events over Day 1 to Day 2, and the trial includes two MN-221 infusion arms and a placebo arm. The registry does not report a complete statistical analysis of that outcome. Consequently, the posted counts are descriptive rather than evidence of a tested treatment contrast.

What randomization contributes

In general, random assignment is intended to make treatment groups comparable with respect to both measured and unmeasured characteristics at the time of assignment. It does not guarantee that groups will be alike in a small trial, and it cannot correct problems that arise after assignment, such as differential missing data or inconsistent outcome ascertainment. The registry identifies the study as randomized but does not report sequence generation, allocation concealment, or implementation details. The adequacy of those procedures cannot be assessed from the registry record.

What masking can and cannot establish

The study is listed as single-blind. In general, masking can reduce the influence of expectations on treatment delivery, participant reporting, and outcome assessment, depending on who is masked and how outcomes are measured. The record does not identify the blinded party or explain how masking was maintained. It is therefore not possible to judge which sources of potential bias the masking was intended to address. A placebo infusion with a dosing volume equivalent to active treatment is described, but further details of treatment similarity are not reported in the registry record.

How to interpret counts

A participant count is a discrete outcome: each person is classified according to whether an event was reported during the specified period. Counts are most informative when paired with the number of participants assessed in each group and clear definitions of the events included. Here, the primary outcome reports counts of 11, 6, and 11, while the separate other-adverse-event counts are 11, 4, and 9. The record does not explain the difference. Enrollment is listed as 17, whereas the primary outcome arm counts are 11, 6, and 11. Because the registry does not clarify these entries, no additional rate or group contrast should be constructed from them.

In general, a confidence interval expresses the uncertainty associated with an estimated quantity under a specified statistical model. It can show which effect sizes remain compatible with the data and assumptions; it is not a guarantee that the true effect lies within a particular interval. No confidence interval is reported for the primary outcome. A p-value, when reported, addresses compatibility with a specified null model, but does not by itself measure clinical importance, precision, or the probability that a hypothesis is true. No p-value or formal test result is reported in the registry record.

Comparisons and analysis choices

This study has two active-treatment arms and a placebo arm, so a complete analysis could involve more than one contrast. The registry does not report which contrasts were prespecified, whether the active arms were to be compared with each other, or which statistical method was planned for the primary outcome. The record indicates that values are missing or not estimable for a two-arm comparison of the binary endpoint. That limitation means a reliable two-arm comparison cannot be reconstructed from the posted summary information. It does not justify substituting an unplanned analysis or treating raw counts as a formal test.

For binary outcomes, possible analyses generally depend on the event counts and denominators, as well as on the intended estimand and design. Different methods may handle sparse data differently. General statistical practice emphasizes stating the comparison, defining the analysis population, and reporting an effect estimate with an uncertainty measure. None of those inferential details is posted for this primary outcome. No recalculated estimate is therefore presented as a sponsor result, and there is no sponsor analysis in the registry record to compare against a recalculation.

The record's planning assumptions describe equal allocation between two arms, a two-sided significance level of 0.05, and a normal approximation. In general, sample-size planning asks how much information a design would need to detect an effect of a chosen size under specified assumptions. A planning illustration is conditional on those assumptions and is not an observed trial result. It is not observed power. The registry does not report the protocol's sample-size justification or establish that the planning assumptions were the assumptions used to design this trial. The observed effect needed for such an illustration is also not presented as a valid comparative estimate in the record.

Why over-dispersion may matter in general

Over-dispersion describes greater variability than a statistical model expects. It can matter for outcomes modeled as counts when observations vary more than the assumed distribution allows, because standard errors and uncertainty estimates may then be too small. That general issue should not be confused with this primary endpoint, which is defined as the number of participants with an event rather than a total count of recurrent events. The registry does not report an over-dispersion assessment or an outcome model, and the available information does not support an assumption about whether repeated events were analyzed.

Finally, statistical interpretation depends on transparent reporting of missing observations, exclusions, and the population analyzed. The record does not report an analysis population, participant flow, missing-data method, or sensitivity analysis. Those omissions prevent assessment of whether the posted outcomes include all randomized participants or only a subset. They also prevent evaluation of how missing outcome information may have affected the reported counts.

10. Exact Estimates for Each Arm

No two-arm comparison is shown for this trial, but each arm's result can still be summarized with exact interval estimates computed from the posted counts. The Clopper-Pearson interval is exact and conservative; the Wilson interval is a common closer-to-nominal alternative; the Bayesian credible interval uses a uniform Beta(1, 1) prior. For small groups the three can differ noticeably.

R code and output

arm    <- c("MN-221 1-hour Infusion", "Placebo", "MN-221 2-hour Infusion")
n      <- c(11, 6, 11)
events <- c(11, 6, 11)
for (i in seq_along(n)) {
  ci <- binom.test(events[i], n[i])$conf.int          # Clopper-Pearson exact interval
  cr <- qbeta(c(0.025, 0.975), 1 + events[i], 1 + n[i] - events[i])   # Bayesian, uniform Beta(1,1) prior
  wi <- (function(x, n) { p <- x / n; z <- qnorm(0.975); d <- 1 + z^2 / n
    c((p + z^2 / (2 * n) - z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d, (p + z^2 / (2 * n) + z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d) })(events[i], n[i])
  cat(sprintf("ARM|%s|%d|%d|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f\n", arm[i], n[i], events[i], 100 * events[i] / n[i],
              100 * ci[1], 100 * ci[2], 100 * wi[1], 100 * wi[2], 100 * cr[1], 100 * cr[2]))
}

ARM  MN-221 1-hour Infusion  11  11  100.0  71.5  100.0  74.1  100.0  73.5  99.8
ARM  Placebo  6  6  100.0  54.1  100.0  61.0  100.0  59.0  99.6
ARM  MN-221 2-hour Infusion  11  11  100.0  71.5  100.0  74.1  100.0  73.5  99.8

11. Multiplicity, Missing Data and Analysis Populations

The record lists a primary safety outcome and a secondary outcome of FEV1 percent predicted change from baseline. It does not report a multiplicity strategy, such as a prespecified hierarchy or adjustment for evaluating multiple outcomes or treatment contrasts. In general, testing several hypotheses can increase the chance of at least one apparently notable result even when no underlying effect exists. Whether that issue affected the study cannot be determined because no inferential results or analysis plan are reported.

The secondary outcome is named, but its results are not reported in the registry record. The registry lists two outcome measures and one posted secondary outcome, but does not provide the measurement details, analysis method, estimate, or uncertainty for the FEV1 result. No conclusion about that outcome can be drawn from its listing alone.

Missing-data handling is also not reported in the registry record. There is no account of participant withdrawals, missed assessments, exclusions, or imputation. The analysis population is not reported, and the record does not state whether the primary analysis included all randomized participants or only those with available outcome data. These omissions matter because a count of observed events may not represent all randomized participants if follow-up or outcome ascertainment was incomplete.

The registry record does not report a statistical analysis plan, sensitivity analyses, or subgroup analyses. It also does not explain the difference between the enrollment figure of 17 and the primary outcome arm counts of 11, 6, and 11. Without clarification of populations and missingness, the scope of the reported safety counts remains uncertain.

12. Safety Results

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

Other (non-serious) adverse events

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

Most frequent non-serious adverse event terms

The serious adverse-event entries list zero affected participants among those at risk in each group: 11 for MN-221 1-hour infusion, 6 for placebo, and 11 for MN-221 2-hour infusion. The registry lists no top serious-event terms. These entries describe what was reported during the available safety record; they do not establish that the risk of serious events is absent or that groups have equivalent safety. In general, an absence of observed events in a small dataset leaves uncertainty about events that might occur but were not observed.

Deaths are not reported in the registry record. That is different from a reported count of zero deaths and should not be interpreted as evidence that no deaths occurred. The separate counts for other adverse events are 11, 4, and 9 participants, respectively. They differ from the primary outcome counts, which are 11, 6, and 11. The registry does not explain the relationship between these entries, so they should be read as distinct reported figures.

The stated timeframe for the primary outcome is Day 1 to Day 2. The record does not report additional follow-up details or event-level descriptions sufficient to characterize timing, severity, duration, or attribution. The safety figures therefore support only a limited description of recorded counts, not a broader comparative safety conclusion.

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

The posted information establishes that the registry describes a randomized, single-blind, parallel-group, placebo-controlled phase 2 study of MN-221 in subjects with moderate to severe asthma. It reports primary outcome counts for adverse events and separate counts for other adverse events, along with serious adverse-event entries. These are descriptive records. They do not, by themselves, establish a treatment effect, a difference between groups, or a causal relationship between MN-221 and any reported event.

The primary outcome counts are 11, 6, and 11 for the MN-221 1-hour infusion, placebo, and MN-221 2-hour infusion arms. The registry does not report a formal comparison, uncertainty estimates, or a p-value. The enrollment figure is 17, while the primary outcome arm counts are 11, 6, and 11; the record does not explain the mismatch. The separate other-adverse-event counts also differ from the primary outcome counts, and the record does not reconcile them. These issues limit how precisely the counts can be interpreted.

The absence of reported serious adverse events is a description of the available entries, not proof that serious events could not occur. Deaths are not reported in the registry record, which cannot be treated as a zero count. The registry also does not report the secondary FEV1 percent predicted result, so the posted information does not establish what happened to that measure.

In general, a clinical trial result is strongest when the endpoint, population, comparison, and analysis are clearly specified and when estimates are accompanied by measures of uncertainty. Those elements are incomplete in the registry record. The results should therefore be understood as a limited account of reported counts from a small study, rather than a precise estimate of comparative effects. The record does not provide enough information to judge the robustness of the analysis, the handling of missing data, or the generalizability of the findings.

14. Why This Trial Matters Statistically

This study illustrates why registry results need to be read as structured evidence rather than as a collection of numbers that automatically form a complete analysis. A randomized design can support comparative inference in principle, but the validity and precision of a comparison depend on coherent denominators, defined outcomes, and transparent analysis methods. Here, the record identifies the design and the safety endpoint but does not report inferential results.

The mismatch between enrollment of 17 and primary outcome arm counts of 11, 6, and 11 is statistically important because denominators determine the meaning of participant counts. The separate adverse-event entries use the same group sizes as the primary outcome, yet their affected-participant counts do not match the primary outcome values. Without an explanation, a reader cannot tell whether the entries reflect different definitions, data handling, or reporting issues. Recognizing that uncertainty is preferable to forcing the figures into a single interpretation.

The record also shows the distinction between an outcome being named and its results being available. FEV1 percent predicted change from baseline is listed as a secondary outcome, but no result is reported in the registry record. Likewise, a planned or illustrative sample-size calculation does not substitute for an observed treatment-effect estimate. Planning depends on assumptions, while analysis describes the data actually collected; those roles should not be confused.

These issues matter for biostatistical interpretation because descriptive counts, design labels, and planned assumptions answer different questions. The registry permits a cautious account of what was recorded, but it does not provide the precision or analytic detail needed for a firm group comparison. Clear reporting of populations, outcome definitions, missing data, and analysis results would be needed to support stronger statistical conclusions.

15. 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 limitations specific to this record constrain interpretation. First, the stated enrollment is 17, while the primary outcome entries show arm counts of 11, 6, and 11. The registry does not explain this discrepancy. It is unclear from the record whether the counts refer to the same participant population, how group denominators were defined, or whether there were differences between enrolled and analyzed participants.

Second, the primary endpoint values do not match the separate counts of participants affected by other adverse events. The primary outcome reports 11, 6, and 11, whereas the other-adverse-event entries report 11, 4, and 9. Definitions and reconciliation are not reported. The serious adverse-event entries list zero affected participants in each arm, but deaths are not reported in the registry record.

Third, no inferential analysis is posted. There is no effect estimate, uncertainty interval, p-value, or description of a statistical model for the primary outcome. The record indicates that values are missing or not estimable for a two-arm comparison of the binary endpoint, so a valid comparative result cannot be reconstructed from the posted summary information. No result is provided for the listed FEV1 percent predicted secondary outcome.

Finally, important methods details are not reported in the registry record: the randomization procedure, the identity of the masked party, dosing rates, analysis populations, participant flow, missing-data handling, and multiplicity strategy. The registry does not report the protocol's sample-size justification or a statistical analysis plan. The limited observation timeframe for the primary outcome is Day 1 to Day 2, and the record does not provide further follow-up details. These limitations mean the posted results are best treated as incomplete descriptive reporting rather than a precise comparative evaluation.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Study Evaluating the Safety and Effects of MN-221 in Subjects With Moderate to Severe Asthma — NCT00679263.
• Registry record last updated 2011-12-19; status last verified 2011-11.
• Results first posted 2011-12-15.
• 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.

19. Record Summary

The registry describes NCT00679263, a completed phase 2 randomized, single-blind, parallel-group, placebo-controlled study of MN-221 in subjects with moderate to severe asthma. It lists two active-treatment arms, MN-221 1-hour infusion and MN-221 2-hour infusion, and a placebo intravenous infusion. Enrollment is listed as 17; the study start is recorded as 2008-02 and primary completion as 2008-07.

The primary outcome was the number of patients reported to have adverse events from Day 1 to Day 2. Its posted arm counts are 11, 6, and 11. Separate other-adverse-event counts are 11, 4, and 9, and serious adverse-event entries list zero affected participants in each group. Deaths are not reported in the registry record. A secondary FEV1 percent predicted change-from-baseline outcome is listed, but its result is not reported in the registry record.

No analyses are posted. The registry does not explain the difference between enrollment and outcome arm counts or reconcile the distinct adverse-event figures. Comparative effect estimates and uncertainty are therefore unavailable.