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 A Study to Evaluate XEN1101 as Adjunctive Therapy in Focal Epilepsy (NCT03796962), a randomized phase 2 study. The primary outcome is Median Percent Change in Focal Seizure Frequency.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT03796962 |
| Phase | Phase 2 |
| Condition | Focal Epilepsy |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Quadruple |
| Enrollment | 325 |
| Arms in the primary outcome | 4 |
| Lead sponsor | Xenon Pharmaceuticals Inc. |
| Results posted | Yes |
2. Clinical Question
Population
Adults diagnosed with focal epilepsy were the intended population. The primary outcome is reported for the mITT population. The registry record lists an enrollment of 325 and identifies focal epilepsy as the condition.
Intervention
Participants received XEN1101 as adjunctive therapy, in capsule doses of 10 mg, 20 mg, or 25 mg. The registry summary describes increasing doses and an optional open-label extension after the blinded treatment period.
Comparator
The comparator was a placebo capsule. The registry record identifies a randomized, double-blind, placebo-controlled design. The outcome results include the three XEN1101 dose groups and placebo.
Primary question
The primary question was how the median percent change in monthly focal seizure frequency from baseline to the double-blind period differed across XEN1101 dose groups and placebo. The specified baseline was the 8 weeks before Day 0, and the treatment period ran through the final dose, up to Day 56.
3. Trial Design
This was a randomized, parallel-group Phase 2 trial with placebo control. The official title describes it as multicenter, double-blind, and intended to evaluate safety, tolerability, and efficacy of XEN1101 as adjunctive therapy for focal-onset epilepsy, followed by an open-label extension. The registry lists quadruple masking. Randomization and masking describe design features; they do not, by themselves, tell readers how treatment assignments were generated or how masking was maintained.
The active treatment groups received capsules containing 10 mg, 20 mg, or 25 mg of XEN1101. The comparison group received a placebo capsule. The registry summary says the blinded treatment period was followed by an optional open-label extension. Results for that extension are not reported in the registry record.
The registry lists enrollment of 325. For the primary outcome, the posted group sizes are 112 for 25 mg, 51 for 20 mg, 46 for 10 mg, and 114 for placebo. Those are the participant counts accompanying the reported outcome, not an explanation of how many participants were randomized, treated, or included at each stage. Reasons for any differences between these counts and the registered enrollment are not reported in the registry record.
The primary outcome timeframe starts at baseline, defined as 8 weeks prior to Day 0, and extends through the final dose, up to Day 56. The record lists a study start of 2019-01-30 and primary completion of 2021-09-02. Its status is active, not recruiting. Details of the randomization procedure, actual allocation proportions, and trial conduct beyond these registry entries 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: 530 subjects were screened; 77 subjects screen failed; 124 subjects that entered the baseline period but were not randomized due seizure/eDiary-based eligibility criteria
Overall Study
| Stage | 25 mg XEN1101 | 20 mg XEN1101 | 10 mg XEN1101 | Placebo |
|---|---|---|---|---|
| STARTED | 114 | 51 | 46 | 114 |
| COMPLETED | 88 | 43 | 45 | 109 |
| NOT COMPLETED | 26 | 8 | 1 | 5 |
Analysis population for the primary outcome, as defined in the registry: mITT
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 | 25 mg XEN1101 | 20 mg XEN1101 | 10 mg XEN1101 | Placebo | Total |
|---|---|---|---|---|---|---|
| Participants analysed | 114 | 51 | 46 | 114 | 325 | |
| Age, Customized: Age | years | 38.7 (SD 13.1) | 41.7 (SD 13.6) | 40.0 (SD 12.1) | 42.9 (SD 13.7) | 40.8 (SD 13.3) |
| Sex: Female, Male: Female | Participants | 54 | 26 | 27 | 61 | 168 |
| Sex: Female, Male: Male | Participants | 60 | 25 | 19 | 53 | 157 |
| Race/Ethnicity, Customized: Asian | Participants | 1 | 0 | 1 | 2 | 4 |
| Race/Ethnicity, Customized: Black or African American | Participants | 2 | 1 | 2 | 7 | 12 |
| Race/Ethnicity, Customized: Native Hawaiian or Other | Participants | 1 | 1 | 0 | 1 | 3 |
| Race/Ethnicity, Customized: White or Caucasian | Participants | 105 | 49 | 42 | 102 | 298 |
| Race/Ethnicity, Customized: Other | Participants | 5 | 0 | 1 | 2 | 8 |
| Monthly seizure frequency in baseline | seizures/month (28 days) | 12.8 (8.4 to 24.6) | 14.5 (7.5 to 36.4) | 17.4 (8.0 to 55.6) | 13.4 (8.0 to 30.1) | 13.5 (7.9 to 30.3) |
6. Primary Endpoint
The registry lists the primary outcome as Median Percent Change in Focal Seizure Frequency, measured over From baseline (8 weeks prior to Day 0) through to the final dose (up to Day 56).
| Element | Registry entry |
|---|---|
| Result type | Median |
| Measure of spread | Inter-Quartile Range |
| Unit | Percent change |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is the median percent change in monthly focal seizure frequency from baseline to the double-blind period. Monthly frequency is expressed over 28 days. The baseline period is the 8 weeks before Day 0; follow-up extends to the final dose, up to Day 56. The primary analysis population is identified as mITT.
A percent change expresses the difference from a participant’s baseline relative to that baseline. In this endpoint, negative values indicate a decrease in seizure frequency under the usual percent-change convention. The registry reports a median for each group, rather than a mean. A median describes the middle of the ordered participant-level values and is less influenced by unusually large or small values than a mean can be. That can be useful when individual changes vary widely or have an asymmetric distribution.
The stated spread measure is the interquartile range (IQR), which describes the middle half of the observed values. It helps show how dispersed participant outcomes are around the median. The posted outcome entries give lower and upper bounds alongside each median, but no separate between-group estimate or test for the primary endpoint is reported in the registry record.
Frequency change is a clinically interpretable summary of how seizure counts changed over the specified period, but a group median does not describe every participant’s experience. It also does not, on its own, establish the precision of a treatment-versus-placebo contrast. That requires a direct contrast and its uncertainty, which are not posted for this primary endpoint.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The posted primary outcome medians are negative in all four groups. The median percent change is -52.8 for 25 mg XEN1101, -46.4 for 20 mg, -33.2 for 10 mg, and -18.2 for placebo. On the percent-change scale, these negative medians indicate decreases from baseline. The largest decrease in the reported group medians is in the 25 mg group, followed by 20 mg, 10 mg, and placebo. This ordering describes the reported summaries; it is not a direct statistical test of differences between groups.
The corresponding reported IQR bounds are -80.4 to -16.9 for 25 mg, -76.7 to -14.0 for 20 mg, -61.8 to 0.0 for 10 mg, and -37.3 to 7.0 for placebo. These intervals describe the distribution of participant-level outcomes within each group, not confidence intervals for the group medians or for treatment contrasts. Their overlap cannot substitute for a formal comparison, and their endpoints do not provide the standard error of a between-group effect.
The primary outcome is stated for the mITT population. The registry record does not report a primary treatment-effect estimate, confidence interval, p-value, or sponsor-reported analysis comparing each dose with placebo. Consequently, the posted primary summaries support a descriptive account of the group medians and their spread, but do not establish how precisely the between-group differences were estimated or whether they meet a prespecified statistical criterion.
The participant counts attached to the primary outcome are 112 for 25 mg, 51 for 20 mg, 46 for 10 mg, and 114 for placebo. Unequal group sizes affect the amount of information available for each group and can affect precision. The registry record does not explain the reasons for these observed outcome counts or report missing-outcome handling, so their implications cannot be fully assessed from the posted entries alone.
Two secondary outcomes are listed. The posted 50% response counts are directionally consistent with the primary summaries: a greater number of participants met the response definition in the active-dose groups than in placebo, with the count pattern varying by dose. Recalculated, unadjusted risk-difference comparisons against placebo are reported for 25 mg and 20 mg, each with p < 0.001. These are not sponsor-reported analyses; no reported analyses are listed for the secondary outcomes. They should therefore be read as unadjusted calculations from the posted counts, not as evidence that the trial’s prespecified analysis plan reached a particular conclusion.
Overall, the registry supports a descriptive comparison of the primary medians and a separate, unadjusted comparison for some secondary response data. It does not supply the inferential details needed to judge the precision or multiplicity-adjusted strength of the primary result. The figures should be interpreted as summaries of this trial’s recorded outcomes, not as a standalone basis for clinical decisions.
9. Statistical Methods Explained
The primary outcome is a continuous measure summarized by the median. It records percent change in monthly focal seizure frequency from baseline through the double-blind period, up to the final dose at Day 56. The registry identifies the spread as an interquartile range. The median and IQR answer descriptive questions about the center and distribution of participant outcomes in each group. They are not, by themselves, a treatment effect estimate with a confidence interval.
What does the median describe?
In general, the median is the middle value after observations are ordered. Half of the observed values lie at or below it and half at or above it, subject to ties and the precise convention used. Unlike a mean, a median is not pulled as strongly by extreme observations. This makes it a useful summary when an outcome is skewed or contains unusually large changes. However, it does not reveal the full distribution: two groups can have the same median while differing in their tails or variability.
In general, the IQR spans the central half of the observations, from the first quartile to the third quartile. A wider IQR indicates greater spread among the middle half of participant results. The registry’s primary outcome entries report median values and IQR bounds for each arm. Those bounds should not be mistaken for a confidence interval around the median or for an interval around the difference between treatment and placebo. A confidence interval for a contrast answers a different question: how uncertain the estimated between-group effect is, under the analysis method.
Why is a direct contrast important?
Randomized trials are designed to compare groups, but separate summaries for each arm do not automatically provide a formal comparison. A direct contrast would quantify the estimated difference in outcome between a dose and placebo and describe its uncertainty. The registry record does not post a primary contrast estimate, confidence interval, or p-value. A reader should therefore avoid treating the ordering of the four medians as a tested dose-response pattern, or interpreting overlap in the reported IQR bounds as a test of statistical significance.
General statistical interpretation distinguishes effect size from precision. An estimated effect describes the direction and magnitude of a contrast. A confidence interval describes the range of values reasonably compatible with the observed data under the model and its assumptions. A p-value measures how unusual the data would be under a specified null hypothesis and statistical model; it does not measure the probability that the null hypothesis is true, nor does it convey the size or clinical importance of an effect. For the primary endpoint, the registry does not report these contrast-level quantities.
How should the response outcome be read?
The 50% response outcome is reported as participant counts. The posted counts are 61 of 112 for 25 mg, 22 of 51 for 20 mg, 13 of 46 for 10 mg, and 17 of 114 for placebo. The outcome title identifies a 50% response threshold, but the registry does not provide further operational detail about how the threshold was applied or how missing measurements were handled.
For the 25 mg and 20 mg groups, simple unadjusted risk-difference comparisons against placebo are recalculated from the posted counts. The reported unadjusted p-values are p < 0.001 for both. These recalculations are not the sponsor’s own analyses; no sponsor-reported analyses are listed. Because the comparisons are unadjusted, they do not account for testing multiple doses or outcomes. The registry does not post a recalculated comparison for 10 mg in the listed comparison results.
General interpretation of a risk difference focuses on the difference between the proportions meeting the response definition in two groups. Its confidence interval describes uncertainty in that difference. The interval and p-value should be read together with the underlying counts, and in light of the analysis being unadjusted. They do not answer whether the comparison was prespecified or whether it remains persuasive after accounting for multiple comparisons; those details are not reported in the registry record.
What do the planning illustrations mean?
The posted sample-size illustrations use the observed response effect as a starting point and show planning scenarios for detecting a stated fraction of that effect. They assume a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. For planning at the full observed effect, the illustrations give 22 participants per arm for 80% power and 29 per arm for 90% power for the 25 mg comparison. For the 20 mg comparison, the corresponding figures are 40 and 53 participants per arm. The illustrations also include planning for 75% and 50% of the observed effect.
These are prospective planning illustrations, not the trial’s design justification and not observed power. The registry record does not report the trial’s sample-size justification or show that these assumptions were used to plan the trial. General statistical reasoning also cautions that planning from an observed effect can be optimistic, because an effect estimated in a particular sample may not represent the effect in future studies. The illustrations do not establish that the original trial had adequate power for its primary endpoint or for all dose comparisons.
The record lists no sponsor-reported analyses. It also does not describe the primary statistical model, adjustment for baseline values, handling of repeated measurements, missing-data procedures, or interim analyses. These omissions matter because each can affect estimates and uncertainty. Without those details, the posted summaries can be described, but the full inferential analysis cannot be reconstructed from the registry record.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists a primary outcome and two secondary outcomes, alongside multiple active doses and placebo. That creates several possible comparisons and outcome tests. In general, multiplicity matters because the chance of at least one false-positive finding can rise when many hypotheses are tested without an appropriate plan. Statistical approaches can control this risk by specifying a hierarchy, adjusting significance thresholds, or using another prespecified procedure. The method depends on the trial’s objectives and analysis plan.
The registry record does not report whether a multiplicity adjustment was planned or applied, how the primary and secondary outcomes were ordered, or whether dose comparisons followed a formal testing sequence. It also does not report interim analyses or stopping rules. The listed p-values for the recalculated response comparisons are unadjusted, so they do not resolve the multiplicity question. No sponsor-reported analyses are listed in the registry.
The primary outcome is identified as belonging to the mITT population, but the registry does not define that population or specify which participants were included in it. It does not report how participants with missing baseline or follow-up seizure data were handled, whether any imputation was used, or whether sensitivity analyses assessed the effect of missing outcomes. These details are important because missingness can affect both the composition of the analyzed population and the estimated outcome distribution.
For the response outcome, counts and denominators are posted, but the record does not explain how participants lacking information on response status were classified or excluded. The available entries therefore cannot show whether missing data differed between arms or how that might influence the comparisons. The registry record also does not report a protocol-level sample-size justification, a statistical analysis plan, or the assumptions used for the primary-endpoint analysis.
These omissions do not prove that the trial lacked formal procedures; they mean those procedures are not reported in the registry record. They limit the ability to assess whether the displayed analyses match a prespecified plan, whether uncertainty accounts for all relevant sources of variation, and how robust the findings are to alternative assumptions.
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 |
|---|---|---|---|
| 25 mg XEN1101 | 3 | 114 | 2.6% |
| 20 mg XEN1101 | 2 | 51 | 3.9% |
| 10 mg XEN1101 | 2 | 46 | 4.3% |
| Placebo | 3 | 114 | 2.6% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| 25 mg XEN1101 | 0 of 114 |
| 20 mg XEN1101 | 0 of 51 |
| 10 mg XEN1101 | 0 of 46 |
| Placebo | 0 of 114 |
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 |
|---|---|
| 25 mg XEN1101 | 97 of 114 |
| 20 mg XEN1101 | 35 of 51 |
| 10 mg XEN1101 | 31 of 46 |
| Placebo | 56 of 114 |
Most frequent serious adverse event terms
| Event term | Organ system | 25 mg XEN1101 | 20 mg XEN1101 | 10 mg XEN1101 | Placebo |
|---|---|---|---|---|---|
| Confusional state | Psychiatric disorders | 0 of 114 | 0 of 51 | 1 of 46 | 0 of 114 |
| Psychogenic seizure | Psychiatric disorders | 1 of 114 | 0 of 51 | 0 of 46 | 0 of 114 |
| Psychotic disorder | Psychiatric disorders | 0 of 114 | 1 of 51 | 0 of 46 | 0 of 114 |
| Somatic delusion | Psychiatric disorders | 0 of 114 | 1 of 51 | 0 of 46 | 0 of 114 |
| Dizziness | Nervous system disorders | 1 of 114 | 0 of 51 | 0 of 46 | 0 of 114 |
| Muscle spasticity | Nervous system disorders | 1 of 114 | 0 of 51 | 0 of 46 | 0 of 114 |
| Seizure | Nervous system disorders | 0 of 114 | 0 of 51 | 1 of 46 | 0 of 114 |
| Partial seizures | Nervous system disorders | 0 of 114 | 0 of 51 | 0 of 46 | 1 of 114 |
| Presyncope | Nervous system disorders | 0 of 114 | 0 of 51 | 0 of 46 | 1 of 114 |
| Hyponatremia | Metabolism and nutrition disorders | 0 of 114 | 0 of 51 | 1 of 46 | 0 of 114 |
Most frequent non-serious adverse event terms
| Event term | Organ system | 25 mg XEN1101 | 20 mg XEN1101 | 10 mg XEN1101 | Placebo |
|---|---|---|---|---|---|
| Dizziness | Nervous system disorders | 36 of 114 | 13 of 51 | 3 of 46 | 8 of 114 |
| Somnolence | Nervous system disorders | 17 of 114 | 11 of 51 | 5 of 46 | 8 of 114 |
| Headache | Nervous system disorders | 9 of 114 | 6 of 51 | 6 of 46 | 9 of 114 |
| Fatigue | General disorders | 14 of 114 | 4 of 51 | 5 of 46 | 6 of 114 |
| Balance disorder | Nervous system disorders | 13 of 114 | 4 of 51 | 2 of 46 | 2 of 114 |
| Tremor | Nervous system disorders | 12 of 114 | 3 of 51 | 3 of 46 | 2 of 114 |
| Anxiety | Psychiatric disorders | 2 of 114 | 5 of 51 | 0 of 46 | 6 of 114 |
| Gait disturbance | General disorders | 8 of 114 | 2 of 51 | 2 of 46 | 1 of 114 |
| Urinary tract infection | Infections and infestations | 2 of 114 | 3 of 51 | 4 of 46 | 4 of 114 |
| Nausea | Gastrointestinal disorders | 7 of 114 | 1 of 51 | 1 of 46 | 3 of 114 |
Serious events with the highest arm-level rate: confusional state (2.2%), seizure (2.2%), hyponatremia (2.2%), psychotic disorder (2.0%), somatic delusion (2.0%).
The safety entries report serious adverse events for each treatment group, with group-specific numbers at risk. Serious adverse events are listed for 3 of 114 participants in the 25 mg group, 2 of 51 in the 20 mg group, 2 of 46 in the 10 mg group, and 3 of 114 in placebo. Deaths are reported as 0 in each group. Other adverse events are reported for 97, 35, 31, and 56 participants, respectively, using the same group order.
The registry also lists serious-adverse-event terms and percentages: Confusional state, 2.2%; Seizure, 2.2%; Hyponatremia, 2.2%; Psychotic disorder, 2.0%; Somatic delusion, 2.0%; and Psychogenic seizure, 0.9%. These entries do not identify the treatment group associated with each term, and the list should not be interpreted as a full description of every event or its relationship to study treatment.
In general, adverse-event counts describe events recorded during the study, not proof that treatment caused an event. Small counts are also imprecise, and simple comparisons between groups may be unstable. The registry entries do not provide a detailed exposure-adjusted analysis, event narratives, or an assessment of causality. The figures describe the posted safety record and should be read separately from the efficacy summaries.
12. What the Result Does, and Does Not, Mean
The posted results describe changes in focal seizure frequency during the blinded treatment period in a randomized Phase 2 trial. The primary group medians are negative, and the largest reported median decrease is in the 25 mg group. The response outcome’s recalculated, unadjusted comparisons for 25 mg and 20 mg have p < 0.001. These findings summarize the data recorded in the registry; they are not, by themselves, a complete account of the trial’s statistical analysis.
For the primary endpoint, the registry provides medians and IQR bounds but not a treatment-versus-placebo estimate, confidence interval, or p-value. That means the size and precision of a formal primary contrast cannot be evaluated from the posted primary results. The IQR describes the spread of individual outcomes, not uncertainty in the difference between groups. The secondary response comparisons provide additional information, but they are recalculated and unadjusted, with no reported multiplicity procedure or sponsor analysis.
In general, statistical evidence and clinical importance are different questions. A p-value does not establish that an effect is large or important, while a group median does not show how all participants responded. The registry does not report a threshold for clinical importance or enough detail to interpret individual-level response patterns beyond the listed response outcome. The results should not be framed as a guarantee of benefit or lack of benefit for any person.
The trial record also does not give the complete analysis plan, missing-data procedures, or results for the open-label extension. It therefore cannot answer how alternative analysis choices might affect the estimates or what happened after the blinded treatment period. The findings are specific to this trial’s registered population, treatment groups, and follow-up window; they should not be generalized beyond that evidence without additional information.
In short, the primary summaries show a dose-ordered pattern in the reported medians, and some secondary response calculations show unadjusted differences from placebo. The registry does not report the inferential analysis needed to establish the precision of the primary treatment contrasts or the handling of multiple secondary comparisons. Descriptive direction, statistical uncertainty, and clinical interpretation should remain distinct.
13. Why This Trial Matters Statistically
This trial is statistically informative because it reports a median-based primary endpoint in a parallel-group randomized design, with several dose groups and a placebo comparator. The outcome is a change from baseline in monthly focal seizure frequency, so interpretation depends both on the distribution of participant-level changes and on a direct comparison between randomized groups. The posted medians allow the group summaries to be described, while the IQRs show that participant outcomes vary within each group.
The record also illustrates why an endpoint summary and an inferential contrast are not interchangeable. A reader can see how the group medians are ordered, but without a primary between-group estimate and its uncertainty, the precision of that ordering cannot be judged. The recalculated response comparisons offer a separate example: a result can be numerically compelling before adjustment, yet still require context about prespecification and multiplicity.
The registered sample-size illustrations add a useful planning perspective, provided they are not confused with the trial’s design or its observed statistical power. They show how planning changes when the assumed effect is reduced from the observed effect. But the registry does not report the trial’s own sample-size rationale, so those illustrations cannot explain why the trial enrolled the number it did or whether it was designed around the primary endpoint.
Finally, the record highlights the value of transparent reporting. Details on analysis populations, missing data, multiplicity, and primary contrasts help readers understand how results were derived and how robust they may be. Their absence in the registry record narrows the conclusions that can be drawn from its posted summaries, even when individual arm-level values are available.
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.
A key trial-specific limitation of the posted efficacy record is that the primary outcome is shown as separate group medians and IQR bounds, without a reported treatment-versus-placebo estimate, confidence interval, or p-value. This leaves the primary contrast’s precision and inferential status unclear. The IQR bounds cannot be used as a substitute for a confidence interval around that contrast.
The primary outcome counts are unequal across the four groups, and the registry does not explain why. The registered enrollment is 325, while the primary outcome group counts are 112, 51, 46, and 114. The record does not describe participant flow, exclusions, or missing outcome data, so the relationship between registered enrollment and the analyzed outcome counts cannot be established from these entries.
The secondary response comparisons are recalculated and unadjusted. The registry lists no sponsor-reported analyses and does not describe any prespecified multiplicity strategy. Results for the other listed secondary outcome, percent change in focal seizure frequency over time, are not reported in the registry record. This limits the ability to assess whether secondary outcomes reinforce the primary analysis under a planned inferential framework.
The registry identifies the primary population as mITT without defining its membership. It does not report the model, baseline adjustment, missing-data method, sensitivity analyses, or interim-analysis procedures. The optional open-label extension is mentioned in the trial description, but its results are not reported in the registry record. The primary follow-up window also ends at the final dose, up to Day 56, so the posted primary results do not describe longer-term outcomes.
These are limitations of the information available in the registry record; they do not establish that the underlying trial lacked additional analyses or documentation. They do mean that conclusions should remain tied to the posted summaries and should not imply more certainty than those summaries support.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: A Study to Evaluate XEN1101 as Adjunctive Therapy in Focal Epilepsy — NCT03796962.
- Registry record last updated 2026-11-05; status last verified 2026-10.
- Results first posted 2024-09-24.
- 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
NCT03796962 is a randomized, parallel-group, placebo-controlled Phase 2 study of XEN1101 as adjunctive therapy in adults with focal epilepsy. The registry describes double-blind treatment and an optional open-label extension. Treatment groups received 10 mg, 20 mg, or 25 mg XEN1101, or placebo. Registered enrollment is 325.
The primary outcome is median percent change in monthly focal seizure frequency from baseline through the final dose, up to Day 56, in the mITT population. The record posts arm-level medians and IQR bounds, but no primary treatment contrast or sponsor-reported analysis. A secondary 50% response outcome has posted counts and recalculated unadjusted comparisons for two dose groups; the other listed secondary outcome is not reported in the registry record.
The record lists serious and other adverse-event counts and reports 0 deaths in each group. It does not report the full statistical analysis plan, missing-data handling, or multiplicity procedures. The registry status is active, not recruiting.