A Study of SEL-212 in Patients With Gout Refractory to Conventional Therapy: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for A Study of SEL-212 in Patients With Gout Refractory to Conventional Therapy (NCT04513366), a randomized phase 3 study. The primary outcome is Proportion of Participants Who Achieved and Maintained Reduction in Serum Uric Acid (sUA) < 6 Milligrams Per Deciliter (mg/dL) for At Least 80% of The Time During Treatment Period 6 (Month 6).

2. Clinical Question

The question is about a sustained threshold-based response, not merely whether serum uric acid changed at a single measurement. The outcome requires participants to meet the threshold for a specified share of the treatment period. As a result, its meaning depends both on the threshold and on how much of the period participants remain below it. The registry also reports outcomes covering serum uric acid change, health status, tophus response, joint tenderness, disability, and gout flares. Those additional measures address different aspects of the study and should not be treated as interchangeable with the primary endpoint.

3. Trial Design

This was a randomized, double-blind, placebo-controlled, parallel-arm Phase 3 study of SEL-212 in patients with gout refractory to conventional therapy. The registry lists quadruple masking. It records enrollment of 112 participants and describes allocation in a 1:1:1 ratio to low-dose SEL-212, high-dose SEL-212, or placebo. The reported primary analysis includes 37 participants in the low-dose arm, 38 in the high-dose arm, and 37 in the placebo arm.

Participants were stratified according to the presence or absence of tophi. The brief summary describes treatment every 28 days for approximately 6 months in each of two replicate trials, identified as SEL-212/301 and SEL-212/302. The registry record analyzed gives results for this trial, with primary and key efficacy analysis at Day 28 of Treatment Period 6. Safety was monitored throughout the study.

The low-dose and high-dose arms shared SEL-037 at 0.2 mg/kg and differed in the listed SEL-110.36 dose: 0.1 mg/kg in the low-dose arm and 0.15 mg/kg in the high-dose arm. The placebo arm received normal saline. The study status is completed. Its start date is 2020-08-18 and its primary completion date is 2022-07-21.

Randomization and blinding are design features intended to support fair comparisons and reduce the influence of expectations or knowledge of treatment assignment. Stratification by tophi status is also part of the stated design. The registry record does not report further details of the randomization procedure, how masking was maintained, or the planned sample-size justification. Those details should not be inferred from the allocation ratio or the number enrolled.

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.

Treatment Phase

Reasons for not completing this period:

Extension Phase

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: Intent-to-Treat Set, which included all randomized and dosed participants, including participants with missing data that were multiple imputed. Participants were analyzed according to randomized treatment.

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: Safety Set, which included all participants who were administered any amount of study drug. Participants were analyzed according to the treatment received.

6. Primary Endpoint

The registry lists the primary outcome as Proportion of Participants Who Achieved and Maintained Reduction in Serum Uric Acid (sUA) < 6 Milligrams Per Deciliter (mg/dL) for At Least 80% of The Time During Treatment Period 6 (Month 6), measured over Month 6.

The primary endpoint is the proportion of participants who achieved and maintained serum uric acid (sUA) below 6 mg/dL for at least 80% of the time during Treatment Period 6, identified as Month 6. It is a binary, participant-level outcome: each participant either meets the endpoint definition or does not. The analysis population is the Intent-to-Treat Set, which included all randomized and dosed participants and included participants with missing data that were multiple imputed; participants were analyzed according to randomized treatment.

A sustained threshold endpoint captures more than a single low sUA measurement. Requiring sUA to remain below the threshold for a specified portion of the period makes the outcome reflect both reaching the target and maintaining it over time. The threshold and duration are part of the endpoint definition, so the result should be interpreted as a response under those particular criteria, not as a general measure of all changes in gout or health.

Threshold-based outcomes are used when the clinical question concerns reaching a defined target. They can be easy to interpret as proportions of participants meeting a response criterion, but they do not show how far above or below the threshold each participant's measurements were. The registry also lists mean and percentage change in sUA as secondary outcomes, which describe change differently. The primary endpoint is therefore a specific sustained-control measure, rather than a complete account of the course of sUA or other outcomes.

7. Results Posted in the Registry

• SEL-212A (Low-dose): 0.0% (0/37) versus 0.0% (0/37) on control; risk difference 0.0 percentage points (95% CI 0.0 to 0.0); unadjusted two-proportion z-test p = n/a.
• SEL-212B (High-dose): 0.0% (0/38) versus 0.0% (0/37) on control; risk difference 0.0 percentage points (95% CI 0.0 to 0.0); unadjusted two-proportion z-test p = n/a.

8. Secondary Efficacy Endpoints

The registry also posts results for secondary outcomes. For each outcome below, the endpoint type, the test applied to the posted summary statistics, the result and its interpretation are given in turn. Secondary endpoints are usually not adjusted for multiple testing, so they support rather than confirm the primary finding.

Change From Baseline in Mean sUA

• Endpoint type: Continuous: a mean value per participant, compared as a difference in means.
• Test: Unadjusted two-sample z-test for the difference in means, using the posted standard errors.
• Result:
  • SEL-212A (Low-dose): mean -5.10 versus 0.20 on control; difference -5.30 (95% CI -6.96 to -3.64), standardized effect d = -1.45; z-test p = <0.001.
  • SEL-212B (High-dose): mean -5.50 versus 0.20 on control; difference -5.70 (95% CI -7.36 to -4.04), standardized effect d = -1.55; z-test p = <0.001.
• Interpretation:
  • The 95% confidence interval excludes no difference, so the mean is statistically lower for SEL-212A (Low-dose) than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.
  • The 95% confidence interval excludes no difference, so the mean is statistically lower for SEL-212B (High-dose) than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.

Percentage Change From Baseline in Mean sUA

• Endpoint type: Continuous: a mean value per participant, compared as a difference in means.
• Test: Unadjusted two-sample z-test for the difference in means, using the posted standard errors.
• Result:
  • SEL-212A (Low-dose): mean -58.70 versus 5.60 on control; difference -64.30 (95% CI -84.88 to -43.72), standardized effect d = -1.42; z-test p = <0.001.
  • SEL-212B (High-dose): mean -64.20 versus 5.60 on control; difference -69.80 (95% CI -89.07 to -50.53), standardized effect d = -1.64; z-test p = <0.001.
• Interpretation:
  • The 95% confidence interval excludes no difference, so the mean is statistically lower for SEL-212A (Low-dose) than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.
  • The 95% confidence interval excludes no difference, so the mean is statistically lower for SEL-212B (High-dose) than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.

Change From Baseline in the Physical Component Summary Score of the Short Form Health Survey (SF-36)

• Endpoint type: Continuous: a mean value per participant, compared as a difference in means.
• Test: Unadjusted two-sample z-test for the difference in means, using the posted standard errors.
• Result:
  • SEL-212A (Low-dose): mean 7.40 versus 3.00 on control; difference 4.40 (95% CI -0.59 to 9.39), standardized effect d = 0.40; z-test p = 0.084.
  • SEL-212B (High-dose): mean 4.80 versus 3.00 on control; difference 1.80 (95% CI -3.05 to 6.65), standardized effect d = 0.17; z-test p = 0.467.
• Interpretation:
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between SEL-212A (Low-dose) and the control. The interval gives the range of effects that remain compatible with the data.
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between SEL-212B (High-dose) and the control. The interval gives the range of effects that remain compatible with the data.

The secondary outcomes cover several domains: sUA change, physical health status, tophus response, sustained sUA reduction in a subset, joint tenderness, disability, and gout flares. Taken together, they add context to the threshold-based primary response by describing related laboratory changes and other measures of health or disease burden. These outcomes do not measure the same construct as the primary endpoint, and their patterns need not match it exactly.

Across the continuous sUA outcomes, the reported arm summaries show decreases in the active-treatment groups and little change or an increase in the placebo group. The sponsor's adjusted analyses also report comparisons for these sUA measures. The SF-36 Physical Component Summary results are less decisive: its sponsor-reported p-values are 0.090 and 0.472. The other secondary outcomes include binary proportions and changes in clinical measures, but a broad interpretation should account for their distinct populations, time frames, and definitions rather than treating them as one combined result.

The registry lists 9 posted secondary outcomes and 20 analyses. Multiple outcomes and comparisons create more opportunities for chance findings. Unless a multiplicity strategy is specified, an isolated secondary p-value should carry less weight than the designated primary analysis. The multiplicity procedure, if any, is not reported in the registry record. The secondary results are therefore useful as supporting or exploratory context, but the registry record does not establish that every secondary finding was confirmatory or protected against the family of repeated tests.

The primary result concerns the prespecified type of response defined by the sustained sUA threshold. Secondary findings can help assess whether related measures show a compatible pattern, but they cannot prove the primary result through repetition across different outcomes. Nor does a similar direction across outcomes remove uncertainty about missing data, modeling choices, or the number of analyses. Interpretation should keep the primary endpoint distinct while using the secondary outcomes to understand the breadth of the posted evidence.

Secondary outcomes registered for this trial, for reference (only those above were recalculated):

• Change From Baseline in Mean sUA
• Percentage Change From Baseline in Mean sUA
• Change From Baseline in the Physical Component Summary Score of the Short Form Health Survey (SF-36)
• Proportion of Participants With at Least Partial Response (PR) (as Best Response) in Overall Tophus Response Evaluation in Participants With Tophi at Baseline
• Proportion of Participants Who Achieved and Maintained Reduction of sUA < 6 mg/dL for at Least 80% of the Time During Month 6 in the Subset of Participants With Tophi at Baseline
• Change From Baseline to Month 6 in Number of Tender Joints
• Change From Baseline to Month 6 in the Total Score of the Health Assessment Questionnaire Disability Index (HAQ-DI)
• Incidence of Gout Flare During Treatment Periods 1-6 (Months 1-6)

9. Statistical Interpretation

10. Statistical Methods Explained

The reported primary comparisons use a Mantel Haenszel method and are expressed as risk differences. A risk difference compares the proportions meeting the endpoint in two groups by subtracting one proportion from the other. It is an absolute contrast in response proportions, rather than a relative comparison. In this trial, the registry reports the low-dose-versus-placebo and high-dose-versus-placebo contrasts separately. No direct comparison of low-dose with high-dose is listed.

What does the confidence interval represent?

A confidence interval expresses the statistical uncertainty around an estimated effect under the assumptions of the analysis. A narrower interval indicates greater precision; a wider interval indicates greater uncertainty about the effect's size. The primary analyses report 97.5% confidence intervals. The interval is not a range containing every participant's outcome, and it is not a guarantee that the true effect lies within its endpoints. It describes uncertainty in the estimated group contrast.

The registry also reports p-values for the primary comparisons. A p-value describes how compatible the observed data are with a specified null hypothesis under the statistical model; it is not the probability that the null hypothesis is true, nor a measure of the size or importance of an effect. The primary p-values are reported as p <.0001. A small p-value does not resolve questions about bias, missing data, clinical importance, or generalizability.

Why can adjustment and stratification matter?

The trial description says participants were stratified according to the presence or absence of tophi, and the sponsor's primary method is identified as Mantel Haenszel. In general, a stratified method can estimate an overall contrast while accounting for the strata used in the analysis. The registry record does not provide the full model specification or detail how the strata were incorporated. The reported analysis should therefore be described by its stated method, without assuming unreported model details.

The primary endpoint analysis population includes randomized and dosed participants, with participants who had missing data included through multiple imputation. Multiple imputation is a general statistical approach that represents uncertainty about missing values by creating multiple completed data sets and combining results across them. Its validity depends on assumptions about the missingness and imputation procedures. The specific imputation model, variables, and assumptions are not reported in the registry record. Consequently, the definition of the analysis set is known, but the detailed handling of missing outcomes cannot be independently assessed from the record.

How should the secondary recalculations be read?

For several continuous secondary outcomes, the posted recalculations are simple, unadjusted comparisons based on the reported group summaries. They are not the sponsor's adjusted analyses. The continuous outcomes are reported as least-squares means with standard errors, while the recalculation fields use an approximate pooled standard deviation derived from those summaries. In general, standard errors describe uncertainty in an estimated mean, while standard deviations describe variation among individual observations. Recovering an approximate standard deviation from a standard error requires assumptions, so the resulting recalculations are illustrative rather than a substitute for individual-level analysis.

The sponsor reports ANCOVA for changes in sUA and percentage change in sUA, and mixed models analysis for the SF-36 Physical Component Summary outcome. ANCOVA and mixed models can account for features of the data and analysis that a simple comparison of group summaries does not. The registry record does not give the complete model specifications, covariates, or covariance assumptions. Differences between an unadjusted recalculation and an adjusted sponsor estimate can therefore arise from method, not only from rounding.

The sample-size illustrations for continuous outcomes use the observed effect as a planning reference, a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. They show participants per arm for 80% power and participants per arm for 90% power at stated fractions of the observed effect. These are planning illustrations, not observed power, and they are not the study's original design justification. The registry record does not report whether these assumptions match the trial's planned design. A sample-size illustration derived from an observed effect should not be read as evidence that the trial was adequately or inadequately powered for a different effect size.

In general, over-dispersion occurs when outcome variability is greater than a model assumes. If present and unaccounted for, it can make standard errors too small and confidence intervals too narrow. The primary endpoint is binary, but the record does not provide model diagnostics or enough detail to assess over-dispersion or other assumption checks. No statistical plan details beyond the named analyses and posted results are reported in the registry record.

11. Confidence Intervals and Precision

The primary risk-difference estimates are accompanied by 97.5% confidence intervals. For low-dose SEL-212 versus placebo, the reported estimate is 0.44 and the interval extends from 0.23 to 0.64. For high-dose SEL-212 versus placebo, the estimate is 0.53 and the interval extends from 0.32 to 0.73. Both intervals lie above zero, while their width indicates that the precise size of the risk difference remains uncertain. The interval is compatible with a range of positive effects rather than a single exact value.

Confidence intervals help separate evidence about direction from precision about magnitude. An interval that excludes zero is consistent with a positive contrast under the reported analysis, but it does not make the point estimate exact. The lower and upper endpoints should be considered alongside the point estimate and the design, population, and analysis used. These intervals apply to each active-versus-placebo comparison; they do not provide an interval for the difference between the two active arms.

The interval widths reflect statistical uncertainty in the estimated contrasts, but they do not capture every possible source of uncertainty. For example, they cannot resolve concerns about how missing outcomes were imputed or whether the analysis assumptions were appropriate. The registry identifies multiple imputation for participants with missing data in the primary analysis population but does not report the imputation model or assumptions. The intervals also do not describe variation in individual responses or guarantee the same precision in other populations.

Thus, the sponsor-reported estimates are more informative than a binary statement of statistical significance alone: they convey both the direction and a plausible range of effect sizes under the analysis. They should be read as estimates for the trial's specified endpoint and comparisons, not as exact quantities or as a direct comparison of SEL-212 dose levels.

12. Analyses Reported by the Sponsor

The sponsor's primary analyses use the Mantel Haenszel method and report risk differences of 0.44 for low-dose SEL-212 versus placebo and 0.53 for high-dose SEL-212 versus placebo. Each comparison is reported with a 97.5% confidence interval and p <.0001. These are the registry's stated analyses for the primary endpoint and are the appropriate estimates to describe as sponsor-reported results.

The raw arm-level primary endpoint proportions are 0.48, 0.56, and 0.04 for low-dose SEL-212, high-dose SEL-212, and placebo, respectively. However, the accompanying simple unadjusted comparison fields list 0.0 for both risk differences. Those zero values are not consistent with the arm proportions or the sponsor's reported contrasts. The registry discrepancy indicator is false, so there is no explicit registry flag explaining the mismatch. The zero-valued fields should be treated as an internal inconsistency, not as meaningful estimates of no difference.

For the continuous secondary outcomes, simple unadjusted recalculations use reported group summaries, whereas sponsor analyses use ANCOVA or mixed models analysis. The methods are not identical, so small differences in estimates or p-values are not necessarily contradictions. The sponsor's full model specifications and adjustment details are not reported in the registry record, limiting a more detailed reconciliation. The recalculations are best regarded as checks based on summaries, not replacements for the sponsor's own analyses.

13. Multiplicity, Missing Data and Analysis Populations

Multiplicity arises when several outcomes or comparisons are tested: the more tests performed, the greater the chance that at least one result may appear unusual by chance alone. The registry lists 10 outcome measures and 20 analyses. It reports 97.5% confidence intervals for the primary comparisons and provides p-values for those analyses, but the multiplicity adjustment strategy is not reported in the registry record. It is therefore not possible to determine from the record whether the primary comparisons were planned within a formal testing hierarchy or how the secondary tests were handled.

This matters especially for secondary outcomes. Their estimates can be informative, but repeated testing without a stated adjustment or prespecified hierarchy makes individual nominal p-values less conclusive. The lack of a reported multiplicity plan does not establish that no plan existed; it means the record does not document one. No interim analyses or stopping rules are reported in the registry record, so none should be assumed.

The primary analysis population is defined as the Intent-to-Treat Set, including randomized and dosed participants and those with missing data that were multiple imputed. Participants were analyzed according to randomized treatment. This definition identifies the analysis population and the stated approach to missing values. It does not reveal the amount or pattern of missingness, the imputation model, or whether sensitivity analyses were performed. Those details are not reported in the registry record.

Multiple imputation is generally intended to preserve information while reflecting uncertainty about missing values, but conclusions can depend on the assumptions and implementation. Without the imputation details, readers cannot assess whether missingness could have affected the estimated response proportions. The endpoint also requires information about sustained sUA status during Treatment Period 6, making the handling of missing measurements relevant to classification. The registry record does not give enough detail to evaluate this aspect independently.

The study's sample-size justification and detailed statistical analysis plan are not reported in the registry record. The planning illustrations attached to continuous secondary comparisons use observed effects and stated assumptions; they do not document the original design calculation and are not observed power. The registry record also does not report an interim efficacy analysis. These gaps limit assessment of how well the analysis followed the original plan, without changing the fact that the stated sponsor results and analysis population are available for interpretation.

14. Safety Results

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

Deaths

Other (non-serious) adverse events

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

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: anaphylactic reaction (5.4%), pneumonia (2.7%), sepsis (2.7%), covid-19 (2.7%), covid-19 pneumonia (2.7%).

The safety summaries list serious adverse events in 10 of 37 participants in the low-dose arm, 5 of 38 in the high-dose arm, and 2 of 37 in the placebo arm. Other adverse events were reported for 31 of 37, 29 of 38, and 27 of 37 participants, respectively. One death is listed in the high-dose group; no deaths are listed for the low-dose or placebo groups. These are counts of participants, not a comparison adjusted for time at risk or other characteristics.

The registry lists anaphylactic reaction at 5.4% among the top serious adverse event terms, with pneumonia, sepsis, COVID-19, COVID-19 pneumonia, and cellulitis each listed at 2.7%. The record does not provide enough detail in these figures alone to establish whether an event was caused by treatment. The counts should be read descriptively, alongside the trial's monitored safety information, rather than as proof of comparative risk or safety.

Comparing event counts across arms requires caution because the groups are small and the summaries do not supply an inferential analysis for these safety comparisons. The listed counts also do not describe event timing, duration, recurrence, or the clinical circumstances of each event. Safety interpretation should therefore remain limited to what the registry reports: observed participant counts, the listed serious-event terms, and the death counts.

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

The posted primary results show that the reported proportion meeting the sustained sUA endpoint was higher in each SEL-212 arm than in placebo, and the sponsor's reported risk differences are positive with confidence intervals above zero. This is evidence about a specific outcome, population, time period, and set of comparisons in this randomized trial. It should not be generalized into a claim about every aspect of gout, every patient, or every possible treatment outcome.

The endpoint does not say that every participant achieved the target, that sUA stayed below the threshold throughout all treatment, or that other symptoms and health measures changed in the same way. It specifically requires sUA below 6 mg/dL for at least 80% of the time during Treatment Period 6. It is a threshold response, not a measure of the magnitude of change for each participant.

The reported comparisons are each against placebo. They do not establish whether one SEL-212 dose level is better than the other, because a direct active-dose comparison is not reported. The confidence intervals provide a range of uncertainty for the sponsor's estimated risk differences, but they do not remove uncertainty about assumptions, missing data, or the applicability of the findings to people outside the study.

The registry includes secondary outcomes and safety summaries that broaden the description of the trial, but they are not interchangeable with the primary endpoint. Secondary tests are numerous, and a multiplicity strategy is not reported. Safety counts are descriptive and do not establish causation. The registry record also does not report the full statistical analysis plan, detailed imputation procedure, or sample-size justification. These absences limit what can be concluded about the design and robustness of all analyses.

Accordingly, the result should be understood as a reported statistical contrast for the trial's primary endpoint, not as a personalized prediction, a complete summary of benefit and harm, or a recommendation about treatment. The evidence should be interpreted with attention to the endpoint definition, analysis methods, uncertainty intervals, secondary outcomes, and limits of the registry record.

16. Why This Trial Matters Statistically

This trial illustrates why endpoint definition matters in clinical research. A sustained target-based response asks whether participants remain below a specified sUA threshold for a specified fraction of a treatment period. That question differs from asking whether the average sUA value changed, and it differs again from asking whether symptoms or physical health changed. The registry reports each of these types of outcomes, but they answer distinct statistical and clinical questions.

It also demonstrates the value of reporting both group proportions and an effect estimate with an interval. The sponsor's risk differences describe the absolute contrast between each SEL-212 arm and placebo, while the confidence intervals communicate uncertainty around those contrasts. A p-value alone would not convey the range of effect sizes compatible with the analysis.

The analysis record shows why methods must be read alongside numbers. The primary result is reported using a stratified Mantel Haenszel method, while the secondary continuous outcomes use ANCOVA or mixed models analysis. Simple recalculations based on group summaries do not reproduce all features of adjusted analyses. In addition, the zero-valued unadjusted primary comparison fields conflict with both the arm proportions and the sponsor's estimates, demonstrating the importance of checking internal coherence rather than interpreting every field at face value.

Finally, the registry makes clear that a completed study record is not necessarily a complete statistical report. The missing details on multiplicity, imputation, sample-size justification, and the full analysis plan constrain evaluation. Good statistical interpretation combines the reported estimates with their uncertainty and the limits of the available methods documentation.

17. 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.
• Participant counts were reconstructed from posted percentages and arm sizes, so small rounding differences are possible.

Several trial-specific limitations arise from the information documented in the registry record. The primary analysis population includes multiple-imputed missing data, but the amount and pattern of missingness, imputation model, and sensitivity analyses are not reported. This leaves uncertainty about how missing observations may have influenced the sustained-response classification.

The registry identifies a Mantel Haenszel primary analysis and says participants were stratified by presence or absence of tophi, but it does not give the full statistical model or detailed analysis plan. The multiplicity strategy for the 20 analyses is also not reported. Without that information, the relationship between the primary comparisons and the wider set of tests cannot be fully assessed. No interim analyses or stopping rules are reported.

The reported comparison fields for the primary outcome include risk differences of 0.0, despite arm-level proportions of 0.48, 0.56, and 0.04 and sponsor-reported risk differences of 0.44 and 0.53. The registry's discrepancy indicator is false, but the displayed values remain internally inconsistent. This makes it important to distinguish the sponsor's named analysis from the incoherent simple comparison values.

For secondary continuous outcomes, summary-based recalculations use approximate variation estimates and do not reproduce the sponsor's adjusted methods. The complete model specifications are not reported. Planning illustrations use observed effects and should not be mistaken for the original sample-size justification or for observed power. The record also does not provide a direct comparison between the SEL-212 dose arms, so conclusions about relative dose performance are not supported by the listed primary analyses.

Safety results are presented as counts and selected serious-event terms, without comparative inference or the detail needed to attribute events to treatment. Together, these limits counsel against extending the registry results beyond the stated population, endpoint, comparisons, and analyses.

18. Related Tutorials

19. Related Statistical Calculators

20. Sources

• ClinicalTrials.gov: A Study of SEL-212 in Patients With Gout Refractory to Conventional Therapy — NCT04513366.
• Registry record last updated 2025-09-11; status last verified 2025-08.
• Results first posted 2025-09-11.
• 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.

21. Record Summary

NCT04513366 is a completed randomized, double-blind, placebo-controlled, parallel-arm Phase 3 trial of SEL-212 in patients with gout refractory to conventional therapy. It enrolled 112 participants and compared low-dose SEL-212, high-dose SEL-212, and normal saline placebo. Participants were stratified by presence or absence of tophi, and the study description reports treatment every 28 days for approximately 6 months.

The primary endpoint was sustained sUA below 6 mg/dL for at least 80% of the time during Treatment Period 6. The sponsor reported positive Mantel Haenszel risk differences for each SEL-212 arm versus placebo, with 97.5% confidence intervals above zero and p <.0001 for both comparisons. The registry also lists secondary outcomes and descriptive safety counts.

Important details, including the full analysis plan, multiplicity strategy, sample-size justification, and multiple-imputation procedures, are not reported in the registry record. The primary comparison fields also contain zero values that conflict with the arm results and sponsor estimates, so the stated sponsor analyses are the interpretable primary results.