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 Efficacy and Safety of Mexidol® in Stroke Therapy (NCT06437626), a randomized phase 3 study. The primary outcome is Change From Baseline in the Modified Rankin Scale (mRS) Scores at the End of the Course of Therapy.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT06437626 |
| Phase | Phase 3 |
| Condition | Ischemic Stroke |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Double |
| Enrollment | 304 |
| Arms in the primary outcome | 2 |
| Lead sponsor | Pharmasoft |
| Results posted | Yes |
2. Clinical Question
The trial asks whether sequential treatment with Mexidol®, when added to standard therapy, is associated with a different change in disability scores than matching placebo added to standard therapy among patients in the acute and early recovery periods of ischemic stroke. The primary measure is change in the Modified Rankin Scale (mRS) from baseline to the end of the course of therapy, at Day 71.
Population
Patients with ischemic stroke in the acute and early recovery periods. The registry record does not report further eligibility criteria in the information available for this analysis.
Intervention
Mexidol® IV 500 mg 2 times a day for 10 days, followed by Mexidol® FORTE 250 orally 250 mg 1 tablet 3 times a day for 60 days. The trial summary describes the treatment as an addition to standard therapy.
Comparator
Matching placebo on the corresponding schedule, also alongside standard therapy. Further details of standard therapy are not reported in the registry record.
Primary question
How did mRS scores change from baseline to Day 71 in each randomized group, and what evidence is available for a between-group difference? The record posts group means and confidence intervals, but a primary between-group estimate and test are not reported.
3. Trial Design
This is a Phase 3, randomized, double-blind, parallel-group, placebo-controlled trial of sequential Mexidol® treatment for ischemic stroke. The official title describes it as prospective, international and multicenter. The registry record does not report the number of participating countries or centers, or further details of the randomization procedure.
The record lists enrollment of 304 and a completed status. The recorded start date is 2019-11-18, and the primary completion date is 2023-08-18. These are registry entries; they do not establish how many participants contributed to each outcome analysis. For the primary mRS endpoint, the posted group counts are 141 for Mexidol® and 138 for placebo. The adverse-event record uses a different at-risk count for each group, so those denominators should be read in the context of the specific outcomes rather than treated as interchangeable.
Participants assigned to Mexidol® received intravenous treatment followed by oral treatment, while the placebo group received matching products on the same schedule. The trial summary describes the comparison as adding Mexidol® or placebo to standard therapy. The registry record does not report how standard therapy was specified or delivered.
The registry lists mRS change as the primary outcome, with baseline and Day 71 as the timeframe. Secondary outcomes include disability categories, neurological symptoms, mobility, cognition, anxiety and depression. The posted material includes numerical results for the two mRS categories, but does not report numerical results for the other listed secondary measures. Details such as the analysis population, missing-data method and prespecified statistical plan 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 | Mexidol® | Placebo |
|---|---|---|
| STARTED | 152 | 152 |
| COMPLETED | 141 | 138 |
| NOT COMPLETED | 11 | 14 |
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 | Mexidol® | Placebo | Total |
|---|---|---|---|---|
| Participants analysed | 152 | 152 | 304 | |
| Age, Continuous | years | 62.45 (SD 7.88) | 62.61 (SD 7.49) | 62.53 (SD 7.68) |
| Sex: Female, Male: Female | Participants | 48 | 52 | 100 |
| Sex: Female, Male: Male | Participants | 104 | 100 | 204 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Asian | Participants | 13 | 16 | 29 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Black or African American | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): White | Participants | 139 | 136 | 275 |
| Race (NIH/OMB): More than one race | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 | 0 | 0 |
| Region of Enrollment: Uzbekistan | participants | 10 | 10 | 20 |
| Region of Enrollment: Kazakhstan | participants | 10 | 10 | 20 |
| Region of Enrollment: Russia | participants | 132 | 132 | 264 |
| Modified Rankin Scale (mRS) | units on a scale | 3.90 (SD 0.50) | 3.94 (SD 0.48) | 3.92 (SD 0.49) |
| Percentage of Subjects Having Modified Rankin Scale (mRS) Scores >3 (Higher Degree of Disability) | Participants | 152 | 152 | 304 |
| Percentage of Subjects Having Modified Rankin Scale (mRS) Scores 0-1 (Normal or Lower Degree of Disa | Participants | 0 | 0 | 0 |
| National Institutes of Health Stroke Scale (NIHSS) | units on a scale | 9 (9 to 11) | 10 (9 to 10) | 9.5 (9 to 10.5) |
| Rivermead Mobility Index (RMI) | units on a scale | 3 (1 to 5) | 3 (2 to 5.5) | 3 (1.5 to 5.5) |
| Montreal Cognitive Assessment (MoCA test) | units on a scale | 22 (19 to 24) | 22 (19 to 25) | 22 (19 to 24.5) |
| Hospital Anxiety and Depression Scale, domain ANXIETY (HADS-A) | units on a scale | 6 (3 to 8) | 5 (3 to 8) | 5 (3 to 8) |
| Hospital Anxiety and Depression Scale, domain DEPRESSION (HADS-D) | units on a scale | 6 (4 to 8) | 5 (3 to 8) | 5 (3 to 8) |
6. Primary Endpoint
The registry lists the primary outcome as Change From Baseline in the Modified Rankin Scale (mRS) Scores at the End of the Course of Therapy, measured over Baseline, Day 71.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | 95% Confidence Interval |
| Unit | score on a scale |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is change in Modified Rankin Scale (mRS) score from baseline to the end of the treatment course. The record defines change as the Day 71 visit score minus the baseline score, with baseline at Day 0-1 and the Day 71 visit recorded as Day 71(+2). The mRS measures disability after stroke. In the registry description, scores range from 0, no symptoms at all, to 5, dead; higher scores indicate a worse outcome.
Because the endpoint is a change score, a negative group mean indicates that scores at the follow-up visit were lower on average than at baseline. On the scale’s stated direction, lower scores represent less disability. This describes the arithmetic direction of the posted scores; it does not by itself establish the clinical importance of a change or a treatment effect.
mRS is used to summarize disability in a single ordinal scale. The trial also lists other measures of neurological symptoms, mobility, cognition, anxiety and depression as secondary outcomes. Those measures address different aspects of recovery and do not replace the primary endpoint. The registry record does not report a threshold for a clinically important change in mRS or an interpretation rule for the size of an individual change.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The posted mean change in mRS was -2.45 in the Mexidol® group, with a 95% confidence interval from -2.7 to -2.23. In the placebo group, the mean change was -2.01, with a 95% confidence interval from -2.25 to -1.87. Both group means are negative, which means the average follow-up score was lower than the average baseline score in each group, under the registry’s definition of change.
The group estimates are descriptive summaries. The registry record does not report a between-group mean difference, its confidence interval, or a primary statistical test. Therefore, the group means alone do not quantify the uncertainty in the contrast between randomized groups. The separate confidence intervals describe uncertainty around each group mean; they are not a substitute for a confidence interval around the treatment comparison. Their overlap or separation should not be used as a stand-alone test of the difference.
The two posted secondary mRS categories show directional patterns consistent with a more favorable distribution in the Mexidol® group: fewer participants are reported in the higher-disability category, while more are reported in the 0-1 category. The accompanying recalculated unadjusted risk differences have confidence intervals that do not include zero, with unadjusted p-values of 0.011 and 0.002, respectively. These are secondary findings and are not the same estimand as the primary mean change in mRS. No adjustment for testing multiple outcomes is reported in the registry record, so the unadjusted p-values should not be treated as confirmatory evidence by themselves.
The posted results support describing the observed group-level changes and the direction of the secondary category contrasts. They do not, on their own, establish the magnitude or statistical uncertainty of a primary between-group effect, whether the observed differences are clinically important, or how results would apply beyond the enrolled trial population. The registry record does not report a primary analysis result that resolves those questions.
9. Statistical Methods Explained
The primary result is a continuous-outcome summary: each group is represented by a mean change in mRS and a 95% confidence interval. The record specifies the endpoint as a change score, not as a comparison of follow-up scores adjusted for baseline. No standard deviation or standard error is posted with the group means, and no direct primary contrast is reported.
What does a confidence interval describe?
General explanation: a confidence interval expresses uncertainty around an estimated quantity under the statistical method used. For the primary outcome, the posted intervals apply to the separate group means. They do not directly estimate the difference between the group means. A reader should look for a contrast and its uncertainty to assess the randomized comparison; those primary comparison results are not reported in the registry record.
How should the secondary comparisons be read?
The secondary mRS outcomes are binary categories, reported as counts of participants meeting each category definition at Day 71. For those outcomes, the posted comparison is an unadjusted risk difference: the proportion in the Mexidol® group minus the proportion in the placebo group. A negative risk difference for the higher-disability category and a positive difference for the 0-1 category correspond to fewer and more participants, respectively, meeting those definitions in the Mexidol® group. The posted risk-difference confidence intervals and unadjusted p-values are recalculations from the posted summary counts, rather than reported sponsor analyses. The registry record lists no reported analyses for these comparisons.
General explanation: a risk difference describes an absolute difference between group proportions. Its confidence interval gives a range of values compatible with the data and method; it is distinct from a relative measure such as a risk ratio or odds ratio. An unadjusted p-value assesses compatibility with a specified null hypothesis under the calculation used, but it does not account for testing multiple outcomes unless a multiplicity procedure is applied. Such an adjustment is not reported in the registry record.
Why can over-dispersion matter?
General explanation: over-dispersion occurs when observed variation is greater than a model assumes. It can make standard errors too small and confidence intervals too narrow if the analysis does not account for it. The posted primary result is a mean and confidence interval, but the registry record does not report the underlying distributional assessment or methods used to calculate that interval. No conclusion about over-dispersion or its handling can therefore be drawn from the posted summary alone.
What do the planning illustrations mean?
The sample-size illustrations use the observed secondary risk-difference effect as a planning reference, with scenarios for 100% of the observed effect, 75% of the observed effect and 50% of the observed effect. They specify a two-sided significance level of 0.05, equal allocation, and a normal approximation. The illustrations give participants per arm for 80% power and participants per arm for 90% power. They are planning calculations, not observed power and not evidence that the trial was designed around those assumptions. The registry record does not report the trial’s own sample-size justification or statistical plan.
General explanation: planning calculations depend on the effect size selected, the outcome definition, the significance threshold, allocation and analysis assumptions. Smaller effects generally require larger groups to detect with comparable power under otherwise similar assumptions. Because these illustrations use fractions of an observed effect, they should not be mistaken for independent confirmation of that effect or as proof that the original study had a particular power.
The registry record does not report an analysis population definition, handling of missing outcome data, adjustment for baseline covariates, or the method used for the primary confidence intervals. These details affect how results are estimated and how uncertainty should be understood. Without them, interpretation should stay close to the posted group summaries and the explicitly labelled unadjusted secondary calculations.
10. Multiplicity, Missing Data and Analysis Populations
The registry record lists a primary mRS change endpoint and several secondary outcomes, including two mRS category outcomes and measures of neurological symptoms, mobility, cognition, anxiety and depression. It posts unadjusted comparisons for the two mRS categories, but does not report a multiplicity strategy, a testing hierarchy, or whether any secondary results were designated confirmatory. The unadjusted p-values therefore need cautious interpretation in the context of the full set of outcomes.
The record does not report how missing outcome data were handled, whether participants were analyzed according to randomized assignment, or how the analysis population was defined. It also does not report whether any participants were excluded from a particular analysis or why the outcome denominators differ from the adverse-event at-risk counts. Without these details, the posted estimates cannot be linked confidently to a specified analysis population or missing-data assumption.
The record lists enrollment of 304, while the posted primary outcome counts are 141 for Mexidol® and 138 for placebo. These figures describe different registry fields and should not be combined or treated as a reconciliation of participant flow. The record does not provide a flow of participants from enrollment through follow-up and analysis, or explain the relationship between the outcome counts and the enrolled population.
The primary endpoint is reported as separate group means with confidence intervals, but no between-group estimate or test is reported. The registry record also does not report the primary statistical model, baseline adjustment, interim analyses, stopping rules, or a sample-size justification. These are not details that can be inferred from the posted summaries. Their absence limits assessment of prespecification, analysis choices and the potential influence of missing data or multiple testing.
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 |
|---|---|---|---|
| Mexidol® | 6 | 152 | 3.9% |
| Placebo | 4 | 152 | 2.6% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Mexidol® | 2 of 152 |
| Placebo | 1 of 152 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Mexidol® | 36 of 152 |
| Placebo | 39 of 152 |
Most frequent serious adverse event terms
| Event term | Organ system | Mexidol® | Placebo |
|---|---|---|---|
| COVID-19 | Infections and infestations | 0 of 152 | 3 of 152 |
| Pneumonia | Infections and infestations | 1 of 152 | 0 of 152 |
| Ischaemic stroke | Nervous system disorders | 1 of 152 | 0 of 152 |
| Brain oedema | Nervous system disorders | 1 of 152 | 0 of 152 |
| Cerebral infarction | Nervous system disorders | 1 of 152 | 0 of 152 |
| Pneumonia viral | Infections and infestations | 1 of 152 | 0 of 152 |
| COVID-19 pneumonia | Infections and infestations | 1 of 152 | 0 of 152 |
| Cerebrovascular accident | Nervous system disorders | 0 of 152 | 1 of 152 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Mexidol® | Placebo |
|---|---|---|---|
| Blood pressure increased | Investigations | 3 of 152 | 5 of 152 |
| Headache | Nervous system disorders | 5 of 152 | 2 of 152 |
| Tachycardia | Cardiac disorders | 3 of 152 | 4 of 152 |
| COVID-19 | Infections and infestations | 3 of 152 | 2 of 152 |
| Diarrhoea | Gastrointestinal disorders | 2 of 152 | 1 of 152 |
| Upper respiratory tract infection | Infections and infestations | 1 of 152 | 2 of 152 |
| Back pain | Musculoskeletal and connective tissue disorders | 2 of 152 | 1 of 152 |
| Urinary tract infection | Infections and infestations | 1 of 152 | 1 of 152 |
| Blood pressure decreased | Investigations | 1 of 152 | 1 of 152 |
| Insomnia | Psychiatric disorders | 2 of 152 | 0 of 152 |
Serious events with the highest arm-level rate: covid-19 (2.0%), pneumonia (0.7%), ischaemic stroke (0.7%), brain oedema (0.7%), cerebral infarction (0.7%).
The adverse-event record reports serious adverse events among 6 participants at risk 152 in the Mexidol® group and 4 participants at risk 152 in the placebo group. Other adverse events are reported for 36 participants at risk 152 in the Mexidol® group and 39 at risk 152 in the placebo group. Deaths are listed as 2 and 1, respectively. These are descriptive counts; the registry record does not report a comparative safety analysis or uncertainty estimates for these outcomes.
The listed serious adverse-event terms include COVID-19 at 2.0%, and Pneumonia, Ischaemic stroke, Brain oedema, Cerebral infarction and Pneumonia viral at 0.7% each. The record does not clarify in this information whether these terms are mutually exclusive, how the percentages were calculated, or whether the events were considered related to study treatment. No causal conclusion should be drawn from the counts alone.
The adverse-event denominators differ from the posted primary outcome counts. They should be interpreted as the at-risk groups recorded for safety, not as a replacement for outcome-specific denominators. The figures describe events recorded in the registry; they do not establish comparative safety in a broader population.
12. What the Result Does, and Does Not, Mean
The primary summaries show negative mean mRS changes in both randomized groups from baseline to Day 71. The Mexidol® group’s mean change is more negative than the placebo group’s posted mean change, but the registry record does not report a direct between-group estimate, confidence interval or primary test. The numerical difference between group summaries is not enough to establish the size, precision or statistical significance of the randomized comparison.
The secondary mRS category findings are directionally consistent with the primary group summaries, but they are unadjusted secondary comparisons. The registry record does not report adjustment for testing multiple outcomes, and numerical results are not posted for the other listed secondary measures. This limits how strongly the secondary findings can support an overall interpretation.
General explanation: statistical evidence and clinical importance are related but distinct. A confidence interval describes uncertainty in an estimate, while clinical importance depends on the meaning of the outcome and the size of a difference that matters to patients and clinicians. The registry record does not report a threshold for clinically important mRS change, and the primary comparison estimate needed to assess the treatment contrast is absent.
These results should not be interpreted as medical advice or as a definitive statement that Mexidol® does or does not work. They describe the outcomes posted for this trial and the limits of what can be inferred from those summaries. The record does not establish the effect for people outside the trial population, the role of particular components of the sequential treatment, or the consequences of any missing data. Further interpretation requires the full analysis details, including a reported primary between-group result and information on the analysis population.
13. Why This Trial Matters Statistically
This trial is statistically informative because it combines randomization and double blinding with a clinically meaningful disability scale and a placebo comparison. The primary endpoint is a change score, so the posted group summaries show the direction of change over time within each group. The distinction between within-group change and a randomized between-group contrast is central: improvement within a group does not by itself show that the intervention group changed differently from the comparator.
The registry record illustrates why uncertainty must be matched to the estimand. Confidence intervals are posted around each group mean, but no confidence interval for the primary contrast is reported. A direct contrast would quantify the between-group difference and its precision, which are needed to interpret the randomized comparison. The secondary risk-difference calculations provide direct contrasts for two categorical outcomes, but they are unadjusted and should not be treated as a substitute for the primary analysis.
The registry also lists a broad set of secondary measures, which could have offered complementary views of neurological status, mobility, cognition and emotional symptoms. Numerical results are not reported for most of those listed measures. The case therefore highlights how outcome registration and result reporting are separate: a listed endpoint does not establish that a result is available or that it supports a particular interpretation.
Finally, the sample-size illustrations are useful for understanding how planning requirements vary when the target effect is expressed as a fraction of an observed effect. They are not the trial’s original design justification and cannot be read as observed power. Clear distinctions among planned calculations, posted group summaries and direct randomized comparisons are essential for a balanced statistical reading.
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 limitation is the absence of a reported primary between-group estimate and test. Separate group means and confidence intervals describe change within each arm, but do not directly quantify the randomized treatment contrast. The registry record also does not report the method used to estimate the primary confidence intervals or whether the comparison adjusted for baseline measurements.
The record does not describe participant flow, the analysis population, or how missing outcomes were handled. The posted endpoint counts and safety at-risk counts differ, and the record does not explain the relationship between them. As a result, the amount and potential influence of missing outcome information cannot be assessed from these summaries.
Numerical secondary results are available for the two mRS categories, but not for the other listed secondary measures. The category comparisons are unadjusted, and no multiplicity approach is reported. Their interpretation is therefore limited by the possibility of selective uncertainty across several outcomes and by the lack of a stated confirmatory hierarchy.
The adverse-event record gives counts and selected terms without a reported comparative analysis, attribution assessment or explanation of how event terms overlap. The information does not establish whether events were related to study treatment. The registry record also does not report further eligibility criteria, participating sites, details of standard therapy, or the trial’s own sample-size justification and statistical plan. These omissions restrict assessment of generalizability, conduct and prespecification.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Efficacy and Safety of Mexidol® in Stroke Therapy — NCT06437626.
- Registry record last updated 2025-12-30; status last verified 2025-12.
- Results first posted 2025-12-08.
- 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.
Continue through the Clinical Biostats statistical pathway
Use this trial's endpoint as a starting point for deeper study of effect measures, confidence intervals, and sample-size planning.
18. Record Summary
NCT06437626 is a completed Phase 3 randomized, double-blind, parallel-group, placebo-controlled trial of sequential Mexidol® treatment for ischemic stroke. The registry lists enrollment of 304, a start date of 2019-11-18 and a primary completion date of 2023-08-18. The trial summary describes Mexidol® or matching placebo as an addition to standard therapy.
The primary outcome is change in mRS from baseline to Day 71. Group means and 95% confidence intervals are posted, but a primary between-group estimate and test are not reported. Two secondary mRS category comparisons are also posted as unadjusted calculations; numerical results for the other listed secondary outcomes are not reported in the registry record. Safety information is presented as event counts, without a reported comparative analysis or attribution details.