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 Intraoperative Floppy Iris Syndrome Undergoing Intraocular Lens Replacement Surgery (NCT02093689), a non-randomized phase 3 study. The primary outcome is Change in Pupil Diameter.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT02093689 |
| Phase | Phase 3 |
| Condition | Intraocular Lens Replacement, Intraoperative Floppy Iris Syndrome |
| Allocation | Non-Randomized |
| Design model | Parallel |
| Masking | Quadruple |
| Enrollment | 18 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Omeros Corporation |
| Results posted | Yes |
2. Clinical Question
Population
Subjects at high risk of intraoperative floppy iris syndrome undergoing intraocular lens replacement surgery. The registry does not report further eligibility details or a fuller description of the analyzed population; no participants’ primary endpoint data were analyzed.
Intervention
OMS302 diluted in balanced salt solution and administered as an irrigation solution. The registry lists OMS302 arms in Part 1 and Part 2.
Comparator
Part 2 included a placebo irrigation solution containing sodium citrate diluted in balanced salt solution. The registry identifies the study allocation as non-randomized, so these arms should not be treated as a like-for-like randomized comparison.
Primary question
The registered primary question was whether pupil diameter changed over time from surgical baseline to the end of the procedure, measured by video capture during intraocular lens replacement surgery. The registry says this measurement method was judged inappropriate in this population and that no participant data were analyzed.
This is a question about a measured intraoperative sign, not a reported comparison of clinical outcomes. Although the study included OMS302 and placebo arms, the non-randomized allocation limits what an arm-to-arm contrast could establish even if outcome data had been analyzed. The registry does not report a treatment-effect estimate, uncertainty interval, or statistical test for the primary endpoint. It also does not report why the measurement methodology was deemed inappropriate. As a result, the registry record does not answer whether the registered pupil-diameter measure differed between the study arms or changed during surgery.
3. Trial Design
The registry describes a Phase 3, parallel study with quadruple masking and non-randomized allocation. It lists an enrollment of 18 and a status of terminated. The recorded study start is 2014-02, and primary completion is recorded as 2014-08. The reason for termination is not reported in the registry record.
Three intervention groups are listed: Part 1 OMS302, Part 2 OMS302, and Part 2 placebo. OMS302 was diluted in balanced salt solution and administered as irrigation solution. The placebo contained 20mM sodium citrate diluted in balanced salt solution and was also administered as irrigation solution. The registry does not provide further details about how participants were assigned to these groups, how the parts related to one another, or whether the part structure reflected different stages of the study.
Non-randomized allocation is important to interpretation. Random assignment is generally used to reduce systematic differences between groups; without it, measured or unmeasured characteristics may differ across arms. Masking can reduce some biases in care or assessment, but it does not make allocation random or ensure that groups are otherwise comparable. The registry does not report enough detail to assess how masking was implemented, who was masked, or whether masking was maintained.
The registered endpoint was an intraoperative measure of pupil diameter. The registry states that the measurement methodology was judged inappropriate for this population and that no participant data were analyzed. It lists one outcome measure and no analyses. Consequently, the design record describes intended groups and an intended question, but not an analyzed primary comparison. Details such as the allocation procedure, planned analysis, and reason for termination are not reported in the registry record.
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: Part 2 of the study was not performed.
Overall Study
| Stage | Part 1 OMS302 | Part 2 OMS302 | Part 2 Placebo |
|---|---|---|---|
| STARTED | 18 | 0 | 0 |
| COMPLETED | 14 | 0 | 0 |
| NOT COMPLETED | 4 | 0 | 0 |
Reasons for not completing this period:
| Reason | Part 1 OMS302 | Part 2 OMS302 | Part 2 Placebo |
|---|---|---|---|
| Physician Decision | 4 | 0 | 0 |
Analysis population for the primary outcome, as defined in the registry: Pupil measurement methodology determined not to be appropriate in this population and data were not analyzed from any participant.
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: All participants who had surgery were included in the analysis
| Characteristic | Unit | Part 1 OMS302 | Part 2 OMS302 | Part 2 Placebo | Total |
|---|---|---|---|---|---|
| Participants analysed | 14 | 0 | 0 | 14 | |
| Age, Categorical: <=18 years | Participants | 0 | — | — | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 0 | — | — | 0 |
| Age, Categorical: >=65 years | Participants | 14 | — | — | 14 |
| Sex: Female, Male: Female | Participants | 0 | 0 | 0 | 0 |
| Sex: Female, Male: Male | Participants | 14 | 0 | 0 | 14 |
6. Primary Endpoint
The registry lists the primary outcome as Change in Pupil Diameter, measured over Intraoperative.
| Element | Registry entry |
|---|---|
| Result type | N/A |
| Measure of spread | not applicable |
| Unit | not stated |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint was change in pupil diameter over time, from surgical baseline to the end of the surgical procedure. The registry specifies that the measure was to be determined by video capture during intraocular lens replacement surgery, with an intraoperative timeframe. A unit and a more detailed endpoint parameter are not reported in the registry record.
In general, a change measure describes how an observed value differs across a defined interval. Using a surgical baseline and an end-of-procedure measurement is intended to characterize pupil diameter during the procedure rather than at a single time alone. Video capture can, in general, provide recorded observations for measurement at specified points, but the registry does not describe the timing rules, image-reading procedures, or quality-control methods used for this endpoint.
The endpoint was selected to assess a sign of intraoperative floppy iris syndrome, according to the study purpose. However, the registry states that the pupil measurement methodology was determined not to be appropriate in this population. Data were therefore not analyzed from any participant. There is no reported endpoint estimate, measure of variability, or comparison between groups. This absence of analysis means the endpoint cannot be used from this record to quantify a change in pupil diameter or to estimate a difference associated with OMS302.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The central statistical fact is that the registered primary outcome was not analyzed. The registry states that the pupil measurement methodology was judged inappropriate in this population and that data were not analyzed from any participant. It reports one outcome measure but no analyses. There is therefore no primary endpoint result to interpret: no change estimate, group contrast, confidence interval, or p-value is reported in the registry record.
This is different from an analyzed result that is imprecise or statistically inconclusive. An imprecise estimate would still provide a numerical summary of the observed data, with uncertainty around that summary. Here, the record says that participant data for the endpoint were not analyzed, so the effect and its precision cannot be assessed. The registry does not report whether data were collected but unusable, whether measurement problems arose before or after collection, or what led to the judgment that the method was inappropriate.
The study included OMS302 and placebo groups, but its allocation is listed as non-randomized. That feature matters because group differences may reflect factors other than the intervention. Masking is listed as quadruple, but masking does not remove potential imbalance caused by non-random allocation. In addition, the outcome itself was not analyzed, so there is no posted group comparison to qualify or interpret.
The safety record gives limited descriptive information for Part 1 OMS302: 14 were at risk for serious adverse events, and 0 were affected; for other adverse events, 14 were at risk and 3 were affected. These figures describe the listed group only. The record does not provide a corresponding placebo group safety summary in the adverse-event information, and a comparison across groups is not supported by these data. Deaths are not reported in the registry record, and serious adverse-event terms are not listed.
Overall, the record documents a planned clinical question and a study that was terminated, but it does not provide an analyzed efficacy result for the primary endpoint. The status alone does not explain why the study ended, and the registry does not report a reason. Neither a positive nor a negative conclusion about the primary endpoint can be drawn from the absence of an analysis.
9. Statistical Methods Explained
Statistical methods describe how observations are converted into estimates and how uncertainty is assessed. For this study, the registry identifies the intended endpoint and groups, but it reports no analyses. The method actually used to analyze pupil-diameter data is therefore not reported in the registry record. Since the endpoint data were not analyzed, there is no estimate or test statistic to interpret.
What would a change endpoint represent?
In general, a change endpoint compares a measurement at a defined starting point with a measurement at a later point. Here, the registry names surgical baseline and the end of the procedure as the endpoints of the measurement interval. A change estimate can describe the average movement in a measurement over that interval, but its interpretation depends on how baseline and end-of-procedure measurements are defined, how observations are obtained, and how missing or unusable measurements are handled. Those operational details are not reported in the registry record. The registry also does not report a unit for pupil diameter or a numerical change estimate.
For a group comparison, an analysis might compare changes between groups or model repeated measurements over time. These are general possibilities, not a description of what this study did. The registry does not identify a planned statistical model, covariates, assumptions, or analysis population. Because it says no participant data were analyzed, it would be inappropriate to attribute any particular analytical approach to the investigators.
Why does allocation matter?
In general, random allocation helps make treatment groups comparable on average with respect to both known and unknown participant characteristics. This study is listed as non-randomized. Group differences, if an outcome comparison had been reported, could therefore reflect differences in participant characteristics, clinical circumstances, or other factors as well as any intervention effect. Statistical adjustment can sometimes address measured differences, but the registry does not report a planned or performed adjustment strategy. Masking is listed as quadruple; masking can help limit certain biases in treatment delivery or outcome assessment, but it does not substitute for random allocation.
The parallel model indicates that the registry describes separate groups rather than a crossover structure. The record lists OMS302 in Part 1 and Part 2, with placebo in Part 2. It does not explain how Part 1 and Part 2 relate analytically or whether any combined analysis was planned. The study is therefore not reduced to a single randomized treatment-versus-control comparison.
How should uncertainty be understood?
In general, a confidence interval gives a range of values compatible with the observed data under the assumptions of the statistical method. A narrow interval indicates greater precision than a wide interval, while an interval that includes effects in different directions may leave the direction uncertain. These interpretations require an actual estimate and interval. Neither is reported for the primary endpoint. A p-value, which in general measures how surprising data would be under a specified null hypothesis and model, is also not reported. No conclusion about statistical significance or precision can be drawn without those results.
The registry includes planning illustrations based on an observed effect, with a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. The effect to detect is expressed as a stated fraction of the observed effect. These are planning assumptions, not a report of the trial's own design or of observed power. The planning values are illustrations, not observed results, and the equal-allocation assumption should not be mistaken for the study's non-randomized allocation. The registry does not report that these assumptions were used to design the trial. In general, sample-size planning asks how many participants would be needed under chosen assumptions; it does not establish what effect was observed. The registry’s time-to-event convention is not relevant to the pupil-diameter endpoint.
Because the endpoint was not analyzed, any planning illustration based on an observed effect cannot be read as a substitute for a trial estimate or as evidence that the study detected an effect. The registry does not report the observed effect value underlying the illustration in the registry record for this analysis. The sponsor’s own analysis cannot be compared with a recalculation because no sponsor analysis or primary endpoint summary is reported.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists one outcome measure and no analyses. It does not report a multiplicity plan, such as how repeated tests, endpoints, or group comparisons would have been handled. Although the study lists multiple arms and more than one study part, the record does not specify which comparisons were planned or whether any were primary or secondary. The presence of several arms alone does not establish that a particular set of statistical comparisons was planned.
In general, multiplicity arises when several statistical questions are tested and can increase the chance of at least one apparently notable result by chance. A prespecified approach may control that risk, but no such approach is reported in the registry record. In this study, the absence of any primary endpoint analysis means there are no reported test results for which multiplicity adjustment can be evaluated.
The registry does not report an analysis population, such as whether all assigned participants or only participants with usable measurements would have been included. It also does not describe how missing data, incomplete videos, or unusable measurements would be handled. The stated reason data were not analyzed is that the pupil measurement methodology was deemed inappropriate in this population; the record does not clarify whether this reflects missing observations, a measurement-validity concern, or another issue. These possibilities should not be inferred from the registry.
Accordingly, neither the impact of missingness nor the suitability of any analysis population can be assessed. The record gives no imputation method, sensitivity analysis, or account of excluded observations. The endpoint non-analysis should be distinguished from a reported analysis that omitted some participants: the registry states that data were not analyzed from any participant.
11. 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 |
|---|---|---|---|
| Part 1 OMS302 | 0 | 14 | 0.0% |
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 |
|---|---|
| Part 1 OMS302 | 3 of 14 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Part 1 OMS302 |
|---|---|---|
| Intraocular pressure increased | Eye disorders | 2 of 14 |
| Zonulolysis | Eye disorders | 1 of 14 |
| Iridocele | Eye disorders | 1 of 14 |
The adverse-event record lists Part 1 OMS302 only. For serious adverse events, 14 were at risk and 0 were affected. For other adverse events, 14 were at risk and 3 were affected. These are counts for the listed group and should not be interpreted as a comparison with placebo; the adverse-event information does not provide a placebo group summary.
The record does not list serious adverse-event terms, so the types of serious events cannot be described from this information. The death count is not reported in the registry record. The figures are descriptive counts, not estimates of comparative risk. In general, a safety comparison requires information on the groups being compared and their corresponding event data; the registry record does not provide those details for a between-group assessment.
These counts also do not establish that an event was caused by the intervention. The registry record does not provide attribution details, event timing, severity beyond the serious-event classification, or follow-up information. The figures should therefore be read narrowly as the recorded number affected among those listed as at risk in Part 1 OMS302, not as a complete characterization of safety across the study.
12. What the Result Does, and Does Not, Mean
The record supports a limited conclusion about what was registered and what was analyzed: the study intended to assess change in pupil diameter during surgery, but the registry says the measurement methodology was judged inappropriate for this population and no participant data were analyzed. There is no reported primary endpoint estimate with which to judge the direction, size, or precision of a change.
This does not mean that the endpoint showed no change, that OMS302 had no effect, or that the placebo and OMS302 groups were equivalent. Those conclusions require analyzed data. The registry’s non-analysis leaves the primary statistical question unanswered. It also does not establish why the measurement approach was deemed inappropriate or why the study was terminated; those reasons are not reported in the registry record.
The study is listed as non-randomized, so even a numerical comparison between its groups would need cautious interpretation. Non-random allocation can leave groups different in ways that influence outcomes. Quadruple masking is reported, but masking alone does not ensure that groups are comparable. In this record, these design considerations are secondary to the more basic limitation that there is no analyzed primary endpoint result.
The safety figures provide only a narrow descriptive account for Part 1 OMS302. They do not establish a comparative safety profile, and the record lacks serious-event terms and a reported death count. The enrollment entry and adverse-event at-risk counts should not be combined or used to infer unreported participant-level details.
In general, a clinical trial result is most informative when its outcome definition, analysis, uncertainty, and population are reported clearly. The registry does not report those elements for an efficacy analysis. Thus, the appropriate reading is not that the intervention succeeded or failed, but that this registry record does not contain an analyzed result that answers the primary question.
13. Why This Trial Matters Statistically
This study illustrates that a registered endpoint and a completed measurement plan do not automatically produce an interpretable statistical result. The registry names a specific intraoperative measure and a defined interval, but also states that the measurement methodology was judged inappropriate in this population. Because no participant data were analyzed, there is no estimate to assess, regardless of the intended design or the listed masking.
The case also shows why measurement validity is a statistical concern, not merely a technical detail. In general, an endpoint must measure the intended feature consistently enough to support meaningful comparisons. If the method is not considered appropriate for the population, an apparent numerical result could be misleading. The registry does not explain the underlying concern, so the precise measurement limitation cannot be characterized further.
Non-randomized allocation presents a separate interpretive issue. In general, randomized allocation helps limit systematic differences between groups, while masking addresses other potential sources of bias. The registry lists both non-randomized allocation and quadruple masking; neither fact should be used to imply a randomized comparison. The groups cannot be treated as a like-for-like control comparison on the basis of this record.
Finally, a terminated study with no primary endpoint analysis highlights the distinction between study status and evidence. Termination alone does not indicate whether the study was stopped for scientific, operational, or other reasons; the reason is not reported in the registry record. The statistical lesson is that transparent reporting of measurement suitability, analysis decisions, and reasons for stopping is necessary to understand what a trial can contribute, including when its intended outcome cannot be analyzed.
14. 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 most important limitation is explicit in the registry: the pupil measurement methodology was determined not to be appropriate in this population, and data were not analyzed from any participant. Consequently, there is no estimate of the primary endpoint and no reported measure of its uncertainty. The registry does not explain what made the methodology inappropriate or whether the concern arose during data collection, measurement, or review.
The allocation is listed as non-randomized. This prevents treating the OMS302 and placebo arms as a like-for-like randomized comparison. Although masking is listed as quadruple, the record does not describe who was masked or how allocation and masking were implemented. The relationship between Part 1 and Part 2 is also not reported in detail.
The registry lists the study as terminated, but the reason for termination is not reported in the registry record. It does not provide a statistical analysis plan, an analysis population, an approach to missing or unusable measurements, or details of any planned covariate adjustment. It also does not report why the study enrolled the recorded number of participants or whether that number reflected a formal sample-size justification.
Safety reporting is limited to Part 1 OMS302 in the listed adverse-event information. Serious-event terms are absent, and the death count is not reported in the registry record. Without corresponding group-level safety information, the record does not support a comparative assessment. These limitations restrict interpretation to the registered design, the stated endpoint issue, and the limited adverse-event counts.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Intraoperative Floppy Iris Syndrome Undergoing Intraocular Lens Replacement Surgery — NCT02093689.
- Registry record last updated 2018-03-13; status last verified 2016-11.
- Results first posted 2018-03-13.
- 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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18. Record Summary
The registry describes a Phase 3, parallel, quadruple-masked, non-randomized study of OMS302 in subjects at high risk of intraoperative floppy iris syndrome undergoing intraocular lens replacement surgery. The listed groups are Part 1 OMS302, Part 2 OMS302, and Part 2 placebo. The study is recorded as terminated, with start in 2014-02 and primary completion in 2014-08.
The primary endpoint was change in pupil diameter from surgical baseline to the end of the procedure, measured by video capture. The registry states that the measurement methodology was not appropriate for this population and that data were not analyzed from any participant. No primary endpoint analysis is reported. The reason for termination and the reason for judging the measurement method inappropriate are not reported in the registry record.
For Part 1 OMS302, the registry lists 0 affected among 14 at risk for serious adverse events and 3 affected among 14 at risk for other adverse events. These figures do not provide a group comparison. The record therefore documents an intended clinical question but does not provide an analyzed efficacy result that answers it.