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 Safety and Efficacy Study of Ozurdex® Compared to Lucentis® in Patients With Branch Retinal Vein Occlusion (NCT01427751), a randomized phase 4 study. The primary outcome is Change From Baseline in Best Corrected Visual Acuity (BCVA).
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01427751 |
| Phase | Phase 4 |
| Condition | Retinal Vein Occlusion, Macular Edema |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Single |
| Enrollment | 307 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Allergan |
| Results posted | Yes |
2. Clinical Question
Population
The study enrolled patients with branch retinal vein occlusion and macular edema. The primary outcome population is described as the intent-to-treat population: all randomized participants with data available for analysis. The record does not give further eligibility details or describe how many participants contributed data to the primary outcome.
Intervention
The intervention was dexamethasone intravitreal implant, Ozurdex®. Participants were scheduled to receive an injection into the study eye on Day 1 and Month 5, with up to one additional treatment thereafter. The registry describes the treatment schedule; it does not report how often participants actually received additional treatment.
Comparator
The comparator was ranibizumab, Lucentis®. Participants were scheduled for injections into the study eye on Day 1 and monthly for five months, with further treatment based on retreatment criteria. The record does not give details about how those criteria were applied or how much additional treatment participants received.
Primary question
The primary question concerns the change from baseline in best corrected visual acuity, measured in letters read correctly on an eye chart, at Month 12. The record does not report the arm-specific changes, the estimated between-arm difference, a confidence interval, or a statistical test for this outcome. It therefore describes what the trial intended to measure, but does not establish the comparative primary outcome result.
3. Trial Design
This was a randomized, single-masked, parallel-group phase 4 study sponsored by Allergan. The registry lists an enrollment of 307 and describes the condition under study as retinal vein occlusion and macular edema. The study status is completed. The recorded start date is 2011-10-11, and the primary completion date is 2014-11-04.
Participants were assigned to Ozurdex® or Lucentis®. The registry gives different planned injection schedules for the study eye. The Ozurdex® arm description specifies injections on Day 1 and Month 5, with up to one additional treatment thereafter. The Lucentis® description specifies an injection on Day 1 and monthly injections for five months, followed by additional treatment based on retreatment criteria. The record does not explain the masking procedure or identify which parties were masked. It also does not report arm-specific randomized enrollment in the design description.
The primary endpoint was change from baseline in best corrected visual acuity (BCVA), with measurements at baseline and Month 12. Secondary outcomes include central retinal subfield thickness measured using optical coherence tomography, visual-acuity improvement or decrease thresholds, time to visual-acuity improvement, change in a visual-function questionnaire score, and failure-related noncompletion of the Month 12 visit. The registry lists seven outcome measures, but it does not report outcome estimates or a statistical comparison for the primary endpoint.
Randomization supports a comparative design, but interpretation still depends on the reported analysis, follow-up, and handling of missing outcome data. Those details 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.
Overall Study
| Stage | Ozurdex® | Lucentis® |
|---|---|---|
| STARTED | 154 | 153 |
| COMPLETED | 112 | 139 |
| NOT COMPLETED | 42 | 14 |
Reasons for not completing this period:
| Reason | Ozurdex® | Lucentis® |
|---|---|---|
| Adverse Event | 18 | 2 |
| No further treatment benefit expected | 5 | 1 |
| Lost to Follow-up | 3 | 1 |
| Withdrawal of consent | 2 | 2 |
| Protocol Violation | 6 | 4 |
| Death | 2 | 0 |
| Other miscellaneous reasons | 6 | 4 |
Analysis population for the primary outcome, as defined in the registry: Participants from the intent-to-treat population, all randomized participants, with data available for analysis.
5. Baseline Characteristics
The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.
| Characteristic | Unit | Ozurdex® | Lucentis® | Total |
|---|---|---|---|---|
| Participants analysed | 154 | 153 | 307 | |
| Age, Continuous | years | 68.4 (SD 10.58) | 65.5 (SD 12.04) | 67.0 (SD 11.41) |
| Sex: Female, Male: Female | Participants | 62 | 66 | 128 |
| Sex: Female, Male: Male | Participants | 92 | 87 | 179 |
6. Primary Endpoint
The registry lists the primary outcome as Change From Baseline in Best Corrected Visual Acuity (BCVA), measured over Baseline, Month 12.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Deviation |
| Unit | letters |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is change from baseline in best corrected visual acuity (BCVA), measured in the study eye using an eye chart. The score is the number of letters read correctly, with a possible range from 0 to 100. The record explains the direction of the scale: fewer letters read correctly indicate worse visual acuity, while more letters indicate better visual acuity. A positive change from baseline therefore represents improvement in the number of letters read correctly.
BCVA provides a direct measure of visual acuity in the study eye, expressed in a unit that can be compared across measurements. Looking at change from baseline relates the Month 12 measurement to each participant’s starting measurement rather than relying only on the final score. The endpoint is a continuous measure, and the registry identifies the planned summary as a mean with standard deviation.
The recorded timeframe is baseline and Month 12. The outcome population is described as all randomized participants with data available for analysis. The registry record does not report the mean changes by arm, the difference between arms, or uncertainty around a comparative estimate. As a result, the endpoint definition can be explained, but the comparative result cannot be interpreted from the record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record defines a clinically interpretable primary measure: change from baseline in the number of eye-chart letters read correctly at Month 12. It also describes a randomized comparison between Ozurdex® and Lucentis®. However, it does not report the primary outcome values. There are no arm-specific mean changes, no between-arm estimate, and no confidence interval or p-value for the primary outcome in the record. The primary result is therefore not reported in the registry record.
Without an estimate of the difference between treatment groups, its direction and magnitude cannot be assessed. Without an interval estimate, the precision of that difference cannot be assessed either. A confidence interval, in general, communicates a range of values compatible with the data and analysis under the method’s assumptions. Its width helps readers judge how much uncertainty remains. No such interval is reported for the primary outcome.
The registry lists secondary outcomes addressing retinal thickness, visual-acuity changes, time to improvement, visual function, and noncompletion attributed to treatment failure. Listing outcomes does not establish what the results were. Their estimates and comparative analyses are not reported in the registry record. In particular, the listed threshold outcomes do not substitute for the continuous primary endpoint or reveal how the study groups compared on it.
The record reports serious adverse event counts by arm: 12 affected participants among 153 at risk in the Ozurdex® group, and 16 among 150 at risk in the Lucentis® group. It also reports other adverse events affecting 127 among 153 at risk in the Ozurdex® group and 104 among 150 at risk in the Lucentis® group. These are descriptive counts. The record does not provide a statistical comparison of these safety figures, and they should not be treated as evidence of a comparative effect. Death counts are not reported in the registry record.
The serious-event term list names angina pectoris, myocardial infarction, myocardial ischaemia, palpitations, subarachnoid haemorrhage, and anxiety, each at 0.7%. The record does not associate those listed terms with a particular arm in the reported term list. These entries therefore provide limited descriptive detail, not a full account of event timing, severity, recurrence, or comparative risk.
Overall, the record supports interpretation of the design and endpoint definitions, and a cautious reading of the posted safety counts. It does not support a conclusion about the primary efficacy comparison because the primary outcome estimates and their uncertainty are not reported.
9. Statistical Methods Explained
What does a change score represent?
Change from baseline expresses how a measurement differs from its starting value. In this trial, the measurement is the number of letters read correctly on an eye chart. The registry states that a positive change represents more letters read correctly and thus improvement in visual acuity. The recorded endpoint summarizes change at Month 12. This approach focuses on within-participant change, while a treatment comparison would ordinarily assess how the change differs between randomized groups.
The registry identifies the endpoint as continuous and specifies a mean with standard deviation as its summary. A mean describes the average change in the analyzed group. A standard deviation describes the spread of individual measurements around that group’s mean; it does not describe uncertainty in the mean itself. The record does not provide the reported means or standard deviations for the primary outcome.
What would a between-group estimate tell readers?
A comparative estimate would quantify the difference in mean change between the Ozurdex® and Lucentis® groups under the analysis used. Its direction would indicate which group had the larger mean change, according to the scale’s stated direction. Its magnitude would describe the size of that difference in letters. The registry record does not report this estimate, so neither its direction nor its magnitude can be described.
A confidence interval is a general statistical tool for expressing uncertainty around an estimate. It gives a range of values that are compatible with the observed data under the chosen model and its assumptions. A narrower interval indicates greater precision than a wider interval, although precision alone does not establish the importance of an effect. No confidence interval for the primary comparison is reported in the registry record.
What does randomization contribute?
Random allocation is intended to create groups that can be compared without assigning treatment according to participants’ characteristics. In general, this can support a causal comparison when the trial is conducted and analyzed appropriately. It does not remove the need to report the analysis population, outcome data, missingness, and statistical methods. The record identifies the design as randomized, but does not report enough analysis detail to assess those aspects for the primary outcome.
The study is described as single-masked. The registry record does not say who was masked or give procedural details. Masking can, in general, reduce the influence of knowledge of treatment assignment on aspects of care, outcome assessment, or reporting, depending on who is masked and how masking is maintained. Those potential safeguards cannot be evaluated from the label alone.
How should the safety counts be understood?
The registry gives counts of participants affected by serious adverse events and by other adverse events, alongside the corresponding numbers at risk for each arm. These are descriptive summaries. They do not by themselves show whether the difference between groups is compatible with chance variation or whether an observed contrast is precise. A statistical comparison would require an estimate and uncertainty measure, neither of which is reported for these safety counts.
The event-term list supplies percentages for six terms, each reported as 0.7%. The registry does not assign these terms to a particular arm in that list. The list should therefore be read as limited event-description information rather than as arm-specific evidence. Death counts are not reported in the registry record.
What do the planning assumptions mean?
The registry describes sample-size illustrations as planning exercises based on the observed effect, with a two-sided significance level of 0.05, equal allocation, and a normal approximation. It says the effect to detect is a stated fraction of the observed effect. These assumptions describe how planning illustrations are framed; they are not observed trial outcomes and are not observed power. No actual illustration values are reported in the record. A planning calculation cannot replace the study’s outcome estimate, and it does not establish that the trial was adequately powered for its primary question.
The registry also reports zero analyses. It does not provide a statistical analysis plan or explain the methods used for the primary outcome. It is consequently not possible to determine from the record whether the intended analysis adjusted for baseline values, how missing observations were handled, or what model was used. Such methods may affect interpretation, and their absence limits independent assessment.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists the primary outcome and several secondary outcomes, including multiple visual-acuity measures and other clinical measures. When several outcomes or comparisons are tested, the chance of finding an apparently notable result by chance can increase. Statistical methods can address this multiplicity, for example by controlling the overall error rate or by identifying a primary comparison in advance. These are general considerations; the registry record does not report a multiplicity strategy or the testing hierarchy.
The registry reports zero analyses and does not include results for the primary or secondary outcomes. It is not possible to determine whether outcome analyses were conducted, how many comparisons were made, or whether any adjustment was used. The absence of reported results should not be interpreted as evidence that no differences were observed.
The primary population is described as all randomized participants with data available for analysis. This identifies the intended population in broad terms, but does not give the number with Month 12 data or describe how missing measurements were treated. The record does not report reasons for missingness, imputation procedures, sensitivity analyses, or whether participants were analyzed according to their randomized assignment. It also lists a secondary outcome concerning noncompletion of the Month 12 visit due to treatment failure, but does not report its results.
Missing data can affect a comparison when participants without measurements differ systematically from those with measurements. The extent and direction of any such effect depend on the amount and pattern of missingness and the assumptions used in analysis. Those details are not reported in the registry record, so the robustness of the primary analysis to missing data cannot be assessed.
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 |
|---|---|---|---|
| Ozurdex® | 12 | 153 | 7.8% |
| Lucentis® | 16 | 150 | 10.7% |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 5% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Ozurdex® | 127 of 153 |
| Lucentis® | 104 of 150 |
Most frequent serious adverse event terms
| Event term | Organ system | Ozurdex® | Lucentis® |
|---|---|---|---|
| Hip fracture | Injury, poisoning and procedural complications | 1 of 153 | 1 of 150 |
| Acute coronary syndrome | Cardiac disorders | 1 of 153 | 0 of 150 |
| Atrial fibrillation | Cardiac disorders | 1 of 153 | 0 of 150 |
| Bradyarrhythmia | Cardiac disorders | 1 of 153 | 0 of 150 |
| Angina pectoris | Cardiac disorders | 0 of 153 | 1 of 150 |
| Myocardial infarction | Cardiac disorders | 0 of 153 | 1 of 150 |
| Myocardial ischaemia | Cardiac disorders | 0 of 153 | 1 of 150 |
| Palpitations | Cardiac disorders | 0 of 153 | 1 of 150 |
| Cerebrovascular accident | Nervous system disorders | 1 of 153 | 0 of 150 |
| Transient ischaemic attack | Nervous system disorders | 1 of 153 | 0 of 150 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Ozurdex® | Lucentis® |
|---|---|---|---|
| Intraocular pressure increased | Investigations | 50 of 153 | 16 of 150 |
| Conjunctival haemorrhage | Eye disorders | 28 of 153 | 17 of 150 |
| Macular oedema | Eye disorders | 20 of 153 | 4 of 150 |
| Visual acuity reduced | Eye disorders | 18 of 153 | 3 of 150 |
| Vitreous floaters | Eye disorders | 9 of 153 | 9 of 150 |
| Dry eye | Eye disorders | 9 of 153 | 7 of 150 |
| Cataract | Eye disorders | 13 of 153 | 2 of 150 |
| Eye pain | Eye disorders | 6 of 153 | 9 of 150 |
| Conjunctivitis | Eye disorders | 6 of 153 | 9 of 150 |
| Hypertension | Vascular disorders | 5 of 153 | 10 of 150 |
Serious events with the highest arm-level rate: angina pectoris (0.7%), myocardial infarction (0.7%), myocardial ischaemia (0.7%), palpitations (0.7%), subarachnoid haemorrhage (0.7%).
The registry reports serious adverse events for each arm using a count of affected participants and a count at risk. In the Ozurdex® group, 12 of 153 participants at risk were affected; in the Lucentis® group, 16 of 150 participants at risk were affected. For other adverse events, the corresponding counts are 127 of 153 in the Ozurdex® group and 104 of 150 in the Lucentis® group. These are descriptive counts, not comparative effect estimates.
The counts do not report event timing, duration, severity beyond the serious-event classification, or whether an individual experienced more than one event. The registry record does not provide confidence intervals or statistical tests for these safety data. The figures should therefore be read as the posted event counts within the recorded groups, without treating them as proof of a difference or similarity between treatments.
The record lists angina pectoris, myocardial infarction, myocardial ischaemia, palpitations, subarachnoid haemorrhage, and anxiety at 0.7% each among the top serious-event terms. The list does not specify the treatment group for each term. Death counts are not reported in the registry record.
12. What the Result Does, and Does Not, Mean
The trial’s stated purpose was to evaluate the safety and efficacy of dexamethasone intravitreal implant compared with ranibizumab in patients with branch retinal vein occlusion. Its primary outcome was change from baseline in BCVA at Month 12. The registry describes a randomized, parallel-group comparison and gives the endpoint’s scale and interpretation, so readers can understand what the study was designed to measure.
What the record does not provide is the primary outcome result. There is no reported mean change for either arm, no between-arm estimate, and no uncertainty measure or statistical test. Consequently, the record cannot establish the direction, size, or precision of the primary comparison. The absence of a reported result is not evidence that the groups were the same, nor evidence that one group had a particular outcome.
The safety counts give descriptive information about participants recorded as affected by serious and other adverse events. Without a comparative analysis and uncertainty estimates, those counts do not determine whether any difference between groups is meaningful or precise. The event-term percentages also lack arm attribution in the list, and death counts are not reported.
The distinction between a trial question and a trial result matters. A protocol or registry description can identify the population, treatments, endpoint, and measurement schedule. It cannot, by itself, answer the comparative question. For that, readers need outcome estimates, their uncertainty, and enough information about analysis populations and missing data to judge the reliability of the comparison. Those details are not reported in the registry record.
Accordingly, the evidence available in this record is strongest for describing the study design, intervention schedules, endpoint definition, and posted safety counts. It is insufficient to draw a conclusion about the primary efficacy comparison. No treatment recommendation follows from these registry entries.
13. Why This Trial Matters Statistically
This trial illustrates why a clearly defined endpoint and a reported treatment comparison are both necessary for statistical interpretation. The registry specifies BCVA change from baseline in letters read correctly, identifies baseline and Month 12 as the measurement times, and explains how positive change relates to the direction of the scale. That information makes the intended outcome understandable and helps readers distinguish a change score from a final score.
Randomization and a parallel-group design establish the broad comparative framework. Yet design labels alone do not reveal the result. The registry record does not report arm-specific primary outcome estimates or a between-group comparison, so readers cannot evaluate effect direction, magnitude, or precision. This is a useful reminder that an endpoint description is not a substitute for statistical results.
The record also demonstrates why safety counts require careful interpretation. Counts of affected participants and numbers at risk are useful descriptive information, but without uncertainty estimates or an analysis they do not establish a comparative safety difference. Event-term percentages without arm attribution further limit interpretation.
Finally, the record names an intent-to-treat population with data available for analysis, but does not explain the missing-data process or statistical methods. Those omissions matter because analysis choices and missing observations can affect estimates. Transparent reporting of estimates, uncertainty, analysis populations, and missing-data handling is central to allowing independent readers to assess a clinical comparison.
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 main limitation for interpreting this specific trial is that the registry record does not report the primary outcome results. It gives no arm-specific mean changes, between-arm estimate, confidence interval, or p-value. The record therefore does not allow an independent assessment of the primary comparison’s size or precision.
The statistical methods are also sparsely described. The registry reports zero analyses and does not specify the model or other methods used for the primary outcome. Although the population is described as all randomized participants with data available for analysis, the record does not say how many had usable Month 12 data or how missing measurements were handled. The effect of missing data on the comparison cannot be assessed.
The registry lists secondary outcomes but does not report their results or describe how multiple outcomes and comparisons were handled. The sample-size assumptions are described as planning illustrations based on an observed effect, but no illustration values are reported. Those assumptions do not establish observed power or substitute for the outcome analysis.
For safety, the record reports counts of affected participants and numbers at risk but not comparative uncertainty estimates. It does not provide event timing or arm attribution for the listed serious-event terms, and death counts are not reported in the registry record. These limitations restrict how far the safety information can be interpreted.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Safety and Efficacy Study of Ozurdex® Compared to Lucentis® in Patients With Branch Retinal Vein Occlusion — NCT01427751.
- Registry record last updated 2019-04-18; status last verified 2019-04.
- Results first posted 2016-02-15.
- 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.
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18. Record Summary
The registry describes a completed, randomized, single-masked, parallel-group phase 4 study sponsored by Allergan, with enrollment of 307. It compares Ozurdex® (dexamethasone intravitreal implant) with Lucentis® (ranibizumab) in patients with branch retinal vein occlusion and macular edema. The primary endpoint is change from baseline in BCVA, measured in letters read correctly, at Month 12.
The record provides treatment schedule descriptions and safety counts. It does not report the primary outcome estimates, a statistical comparison, confidence intervals, or p-values. It also does not report the methods used to analyze the primary outcome or how missing observations were handled. The posted information therefore describes the trial question and some safety data, but does not provide enough results to assess the primary comparative outcome.