Evaluate the Therapeutic Effects and Safety of ALK4290 in Patients With Refractory Wet Age-Related Macular Degeneration: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Evaluate the Therapeutic Effects and Safety of ALK4290 in Patients With Refractory Wet Age-Related Macular Degeneration (NCT03558074), a na phase 2 study. The primary outcome is Best Corrected Visual Acuity (BCVA).

2. Clinical Question

3. Trial Design

This was a completed Phase 2, single-group, open-label study of ALK4290 for patients with refractory wet age-related macular degeneration. The registry records an enrollment of 26. The study drug was given as 800 mg daily during a 6-week treatment period. The listed primary endpoint compares best corrected visual acuity at baseline with the measure at 6 weeks.

There was no randomized allocation and no masking. Because there was no control group, the design describes change during treatment rather than a treatment contrast against a concurrent comparator. Changes over time in a single group can reflect multiple influences, including natural variation, measurement variability, and other events during the study. The design cannot separate those influences from any change associated with treatment.

The primary endpoint population is named the Evaluable Set, but its definition and the number included in the endpoint analysis are not reported in the registry record. The record lists treatment-emergent adverse events as a secondary outcome. It does not report an analysis plan, and the number of analyses is listed as 0. No specific statistical tests or methods for the primary endpoint are reported.

The study status is completed. Its recorded start date is 2018-04-20, and its primary completion date is 2018-11-29. Completion status does not itself establish that endpoint results are available in the registry record. The record describes the intended assessment but does not give the BCVA change estimate or its standard deviation.

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

Analysis population for the primary outcome, as defined in the registry: Evaluable Set

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 Best Corrected Visual Acuity (BCVA), measured over Baseline to 6 weeks.

The primary endpoint is mean change in best corrected visual acuity (BCVA), measured in letters, from baseline to 6 weeks. The registry states that BCVA was assessed using the Early Treatment Diabetic Retinopathy Study (ETDRS) testing method, which records changes in vision based on the number of letters correctly read. The analysis population is identified as the Evaluable Set.

As a general statistical point, a continuous outcome such as a letter score can be described by its mean and standard deviation. A mean change gives the average direction and size of change in the analyzed group; the standard deviation describes variation in individual changes around that average. Both are useful because an average alone does not show how spread out participants’ measurements were.

BCVA is used in this study as a measure of visual function. A change score compares the endpoint measurement with the baseline measurement for the relevant participants. The registry record does not report the mean change, the standard deviation, the number included in the endpoint analysis, or an uncertainty interval. It is therefore not possible to describe the observed change or its precision from the registry record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry describes a continuous primary outcome: mean change in BCVA, measured in ETDRS letters from baseline to 6 weeks. It identifies standard deviation as the dispersion measure. It does not report the statistical test, model, confidence interval, or p-value used for this endpoint. The explanations below are general statistical context, not a description of an analysis method confirmed in the registry record.

What does a mean change represent?

For a continuous outcome, a mean summarizes the average value across the measurements included in an analysis. For a change endpoint, the relevant quantity is the average difference between the follow-up and baseline measurements, using the study’s stated definition. A positive or negative mean can describe direction only when the result and scoring convention are available. The registry names the endpoint but does not report the mean change, so its direction and size are not reported in the registry record.

The standard deviation describes how much individual values vary around the mean. It is not the same as the uncertainty in the mean. A group can have a mean estimate with substantial or limited uncertainty depending on the amount of variation and the number of observations analyzed. The registry identifies standard deviation as the dispersion measure but provides no value for it.

Why does the analysis population matter?

The registry names the Evaluable Set as the population for the primary endpoint. In general, a named analysis population determines which participants contribute data to an estimate. The criteria for inclusion can affect the estimate, particularly if participants without complete follow-up measurements are excluded. The record does not define the Evaluable Set or report its size. It also does not describe how missing baseline or 6-week measurements were handled. Therefore, the endpoint’s analysis denominator and the consequences of missing data are not reported in the registry record.

What would an uncertainty interval add?

In general, a confidence interval communicates uncertainty around an estimated effect under the assumptions of the analysis. A narrower interval indicates greater precision than a wider interval, while an interval spanning values in different directions can leave the direction of the underlying effect uncertain. These are general interpretations, not findings from this trial: no confidence interval for BCVA change is reported in the registry record.

A p-value, if reported, would address how compatible the observed data are with a specified statistical null model. It would not by itself describe the size or clinical importance of a change. The registry record reports no p-value or test for the primary endpoint. Statistical significance, and the relation between any result and a clinically meaningful threshold, cannot therefore be assessed from the record.

What can the design support?

In a single-group study, a baseline-to-follow-up analysis can describe change within the observed group. General methods for continuous paired measurements may account for the fact that baseline and follow-up values come from the same participants. However, the registry does not identify a specific method, so it would be inappropriate to attribute a paired test, model, or adjustment to this study.

A single-group change is not a randomized treatment effect. Without a concurrent control group, the observed change cannot be separated from temporal trends, measurement variability, or other influences. This is a design limitation, regardless of which statistical method is used to summarize the data.

How should planning illustrations be understood?

The record describes a planning illustration based on the observed effect, using a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. It describes the effect to detect as a stated fraction of the observed effect. Such an illustration is hypothetical planning information, not an observed result and not observed power. The record does not give the underlying BCVA result needed to interpret an effect-based illustration in this account. The study itself is single-group, so the two-arm allocation assumption does not describe its actual design.

Overall, the registry identifies the endpoint type, timeframe, population label, and dispersion measure, but does not report the endpoint estimate or the inferential methods. Statistical interpretation should be limited to those design and reporting details.

10. Confidence Intervals for Each Arm

No two-arm comparison is shown for this trial, but each arm's mean can be given with a t-based 95% confidence interval computed from the posted mean, spread and number of participants.

R code and output

arm <- c("Active")
n   <- c(25)
m   <- c(2)
sp  <- c(6.96)
sd  <- sp      # posted standard deviations
for (i in seq_along(n)) {
  se <- sd[i] / sqrt(n[i]); h <- qt(0.975, n[i] - 1) * se
  cat(sprintf("CARM|%s|%d|%.3f|%.3f|%.3f|%.3f\n", arm[i], n[i], m[i], sd[i], m[i] - h, m[i] + h))
}

CARM  Active  25  2.000  6.960  -0.873  4.873

11. Multiplicity, Missing Data and Analysis Populations

The registry lists BCVA change as the primary outcome and incidence of treatment-emergent adverse events as a secondary outcome. It records 2 outcome measures and 0 analyses. The record does not report a statistical analysis plan or a method for controlling multiplicity. It is therefore not reported in the registry record whether any adjustment or hierarchy was planned for multiple outcomes, time points, or analyses.

As a general statistical concept, multiplicity arises when several hypotheses or outcomes are tested. Without a prespecified approach, interpreting isolated p-values can overstate the strength of evidence. Here, no primary-endpoint p-value is reported, and the record does not describe inferential testing for the secondary safety outcome. No claim about multiplicity-adjusted or unadjusted significance can be made.

The primary endpoint population is called the Evaluable Set, but the record does not state its inclusion criteria or size. It does not report the number with baseline and 6-week BCVA measurements, reasons for missing measurements, or a method for handling missing data. Missingness could affect a continuous-outcome estimate if the available measurements differ systematically from those not observed; this is a general concern, not a claim about what happened in this study.

Enrollment is recorded as 26, but that figure does not establish how many participants contributed to the primary endpoint analysis. The registry record does not report whether all enrolled participants were included in the endpoint analysis. Accordingly, completeness, exclusions, and the impact of missing data cannot be assessed.

12. 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 non-serious adverse event terms

The registry’s adverse-event record lists 26 participants at risk for serious adverse events and 0 affected. It lists 26 at risk for other adverse events and 3 affected. The recorded number of deaths is 0. These are counts as recorded; no percentages or additional rate calculations are needed to describe them.

The serious-event count is distinct from the count for other adverse events. A record of 0 participants affected by a serious adverse event does not mean that no adverse events of any kind were recorded: the registry lists 3 participants affected by other adverse events. The record does not provide the terms for serious adverse events; the serious-event term list is empty. It also does not identify the types of the other events in the information available for this analysis.

The registry identifies treatment-emergent adverse events as a secondary outcome, but the safety observation timeframe and event-relatedness assessments are not reported in the registry record. These counts alone do not establish cause, comparative safety, or the frequency of events outside the recorded study group.

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

The registry record establishes that a Phase 2, open-label, single-group study assessed ALK4290 in patients with refractory wAMD. It specifies daily dosing of 800 mg over 6 weeks and defines the primary endpoint as mean change in BCVA from baseline to 6 weeks. It also records adverse-event counts. These details describe the study question and its design, but the primary endpoint result itself is not reported in the registry record.

Without the mean change and its variability, the posted record does not show whether BCVA changed on average, how large any change was, or how variable individual changes were. Without an uncertainty interval or an inferential result, the precision and statistical evidence for a change also cannot be evaluated. The endpoint description is not a substitute for those results.

Even if a within-group change were reported, the single-group design would not establish that ALK4290 caused the change. A concurrent comparator can help account for changes that might occur over time for reasons other than the intervention. No such comparison is part of this study design. The registry record therefore cannot support a randomized comparison with another treatment or a control condition.

The 6-week endpoint is specific to the stated assessment timeframe. It does not establish longer-term change or safety. The record also does not describe the Evaluable Set criteria or missing-data handling, limiting assessment of who contributed to the endpoint estimate.

The safety counts should be read as descriptive observations in the study group. They do not provide a comparative estimate and do not establish whether an event was caused by treatment. Overall, the posted information describes the trial’s scope and some safety counts, but does not report the primary efficacy result needed to characterize the observed BCVA change.

14. Why This Trial Matters Statistically

This trial is statistically notable because its primary question concerns change in a continuous visual-acuity measure, while its design is a single-group study. A mean change and its variability would describe the observed group’s experience over the stated timeframe. However, without a comparator, such a change would not isolate the effect of treatment from changes that could occur over time or from measurement variation.

The registry gives useful context for interpreting what an endpoint result would represent: the measure is BCVA in ETDRS letters, the comparison is baseline to 6 weeks, and the intended population is the Evaluable Set. It also identifies standard deviation as the dispersion measure. At the same time, the registry does not report the mean change, standard deviation, analysis population size, or uncertainty interval. This illustrates why an endpoint definition and an endpoint result are not interchangeable.

The distinction between enrollment and analysis population is also important. Enrollment is listed as 26, but the Evaluable Set is not defined and its size is not reported. Readers therefore cannot determine from the record how many participants contributed to the primary estimate or how missing measurements were handled.

The safety figures are descriptive counts rather than a comparison between groups. They provide a record of serious and other adverse events in the study group, but not a comparative safety estimate. In general, a careful statistical reading keeps design, endpoint definition, analysis population, uncertainty, and causal interpretation separate. The available record supports the first two descriptions and limited safety counts, while leaving the primary efficacy result and its precision unreported.

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.

The main design limitation is the absence of a concurrent control group. The study is identified as single-group, open-label, and unmasked, with allocation listed as not applicable. As a result, it cannot provide a randomized comparison or separate change over time from change attributable to treatment. Open-label conduct can also leave outcomes more open to expectations or other influences, although the registry does not report whether such influences occurred.

The primary assessment is limited to baseline to 6 weeks, the timeframe stated for BCVA change. The record does not provide a later primary endpoint result. The study therefore does not establish the durability of any change beyond the reported assessment timeframe.

The registry lists enrollment as 26, but does not report the number analyzed for BCVA. It names the Evaluable Set without defining it. Missing-data handling, reasons for any missing measurements, and exclusions from the endpoint analysis are not reported in the registry record. These omissions limit evaluation of the endpoint estimate’s representativeness.

The primary result itself is not reported: there is no mean change, standard deviation, confidence interval, or p-value. Consequently, neither the magnitude nor the precision of the endpoint can be assessed. The registry also does not report the statistical analysis method or a multiplicity plan. The safety record gives counts but does not report event types for other adverse events, a safety observation timeframe, or event-relatedness assessments. These limitations constrain interpretation of both efficacy and safety.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Evaluate the Therapeutic Effects and Safety of ALK4290 in Patients With Refractory Wet Age-Related Macular Degeneration — NCT03558074.
• Registry record last updated 2020-12-22; status last verified 2020-11.
• Results first posted 2020-08-28.
• 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 record describes a completed Phase 2, open-label, single-group study of ALK4290 in refractory wet age-related macular degeneration. Enrollment was 26. The intervention was 800 mg daily over a 6-week dosing period. The primary endpoint was mean change in BCVA, measured in ETDRS letters from baseline to 6 weeks in the Evaluable Set.

The registry lists 0 participants affected by serious adverse events, 3 affected by other adverse events, and 0 deaths. It does not report the primary BCVA result, its variability, or an uncertainty estimate. The Evaluable Set definition, missing-data methods, and statistical analysis plan are also not reported in the registry record. Because there was no control group, the design does not support a like-for-like treatment comparison.