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 Study to Assess the Efficacy of Mayzent on Microglia in Secondary Progressive Multiple Sclerosis (NCT04925557), a non-randomized phase 2, phase 3 study. The primary outcome is Change From Baseline in PET Activation at 12 Months.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT04925557 |
| Phase | Phase 2, Phase 3 |
| Condition | Secondary-progressive Multiple Sclerosis |
| Allocation | Non-Randomized |
| Design model | Parallel |
| Masking | Single |
| Enrollment | 8 |
| Arms in the primary outcome | n/a |
| Lead sponsor | State University of New York at Buffalo |
| Results posted | Yes |
2. Clinical Question
Population
Patients diagnosed with secondary-progressive multiple sclerosis who had active disease. The arm descriptions specify patients whose neurologists had prescribed Mayzent or Ocrevus. The registry lists enrollment as 8.
Intervention
Mayzent, with the study intended to assess changes in PET activation of PBR06 in brain regions described as lesional and non-lesional NAWM and NAGM, as well as in the peri-plaque area of chronic lesions.
Comparator
Ocrevus, described as an active control. Patients in this group had been prescribed Ocrevus by their neurologist. Treatment was not randomly assigned.
Primary question
What change from baseline in PET activation at 12 months would be observed among patients treated with Mayzent? The broader study objective was to compare microglial activation between Mayzent and Ocrevus, but the registry's primary outcome description focuses on patients under treatment with Mayzent.
The stated primary outcome is a change in PET activation at 12 months. The record says that the study was terminated and that no subject had further data collected after the initial visit. It therefore does not report the planned follow-up information needed to assess that change. A comparative treatment effect cannot be determined from the recorded primary outcome.
3. Trial Design
The registry describes a prospective, longitudinal, controlled, observational comparison with a parallel-group model. Allocation is listed as non-randomized. Patients were in the Mayzent or Ocrevus group according to treatment prescribed by their neurologist, rather than assignment by randomization. This matters because the groups may differ in ways that also relate to measured outcomes; the registry does not report methods for addressing such differences.
The official title describes the study as open-label and single-blind. The masking entry is single, but the record does not identify who was blinded or what information was masked. The registry lists phase 2 and phase 3; it does not explain those designations in relation to the observational comparison.
Enrollment is listed as 8. The sponsor is State University of New York at Buffalo. The recorded start date is 2021-11-13, the primary completion date is 2023-06-01, and the study status is terminated. The record's primary outcome description states that no subject had further data collected after the initial visit. Thus, the intended longitudinal assessments are not represented by continued follow-up in the primary outcome record.
The registry identifies Mayzent and Ocrevus as the interventions and describes Ocrevus as the active control. It also lists 14 outcome measures. The registry record does not report a detailed statistical analysis plan, the reasons for termination, or the rationale for the enrollment target. Because allocation was not randomized and the record contains no follow-up outcome data, the design does not support estimating a comparative change from the stated primary endpoint.
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 | Ocrevus | Mayzent |
|---|---|---|
| STARTED | 5 | 3 |
| COMPLETED | 0 | 0 |
| NOT COMPLETED | 5 | 3 |
Reasons for not completing this period:
| Reason | Ocrevus | Mayzent |
|---|---|---|
| Study closed | 5 | 3 |
Analysis population for the primary outcome, as defined in the registry: Study was terminated. No subject had any further data collected after the initial visit.
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: Patients with relapsing remitting Multiple Sclerosis.
| Characteristic | Unit | Ocrevus | Mayzent | Total |
|---|---|---|---|---|
| Participants analysed | 5 | 3 | 8 | |
| Age, Continuous | years | 51 (39 to 63) | 53 (49 to 55) | 52 (44 to 59) |
| Sex: Female, Male: Female | Participants | 2 | 1 | 3 |
| Sex: Female, Male: Male | Participants | 3 | 2 | 5 |
| Race and Ethnicity Not Collected | Participants | — | — | 0 |
6. Primary Endpoint
The registry lists the primary outcome as Change From Baseline in PET Activation at 12 Months, measured over 12 months.
| Element | Registry entry |
|---|---|
| Result type | N/A |
| Measure of spread | not applicable |
| Unit | not stated |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is change from baseline in PET activation of PBR06 at 12 months. The description names lesional and non-lesional NAWM and NAGM in the brain, and says the assessment concerns patients under treatment with Mayzent. The study's broader objective also mentions microglial activation in the peri-plaque area of chronic lesions. The endpoint unit and the parameter used to summarize the change are not reported in the registry record.
In general, a change-from-baseline endpoint compares a follow-up measurement with a participant's starting measurement. This can describe within-person change and, when follow-up is available in comparison groups, can support a comparison of change between groups. PET activation is the imaging measure specified by this study; the registry does not provide further measurement details or explain how activation was quantified.
The registry states that the study was terminated and no subject had further data collected after the initial visit. Consequently, the 12-month change cannot be evaluated from the recorded follow-up. No primary endpoint estimate, uncertainty interval, or statistical test is reported in the registry record. The endpoint's intended measurement should therefore be distinguished from an observed result: the record describes what the study planned to measure, but does not provide the longitudinal data needed to report that measurement.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The main interpretive fact is that the registry record does not contain 12-month outcome data for the primary endpoint. It states that the study was terminated and that no subject had further data collected after the initial visit. The primary outcome is defined as change from baseline in PET activation at 12 months, so the specified follow-up change is not available for interpretation. The registry lists no analyses.
This absence of an endpoint estimate is different from an estimate showing no change or no difference. Without a recorded follow-up measurement, the direction and magnitude of change cannot be established. The record also does not report a confidence interval or a p-value for the primary endpoint. It is therefore not possible to judge the precision of a treatment comparison from this outcome.
The study was non-randomized, and treatment was prescribed by neurologists. In general, non-randomized groups can differ at baseline or in other relevant characteristics. Such differences can complicate attribution of a measured outcome to treatment. Here, however, the more immediate constraint is that the registry describes no data collection beyond the initial visit. No adjustment method or baseline-comparability analysis is reported in the registry record.
The planned comparison was Mayzent against an active Ocrevus group, but the primary outcome description specifically refers to patients under treatment with Mayzent. The registry does not provide a primary-outcome comparison estimate between the groups. It lists secondary outcomes concerning PET activation at several follow-up times and new ultrasmall superparamagnetic iron oxide particles, but the record does not report results for these outcomes.
In general, a confidence interval communicates the range of values compatible with an estimate under the analysis assumptions. A narrow interval indicates greater statistical precision than a wide one, but neither can be interpreted without an estimate and the underlying data. No such primary outcome interval or estimate is reported. Similarly, absence of a reported test result should not be treated as evidence for or against a treatment difference.
The posted safety counts are separate from the missing longitudinal efficacy outcome. They record adverse events for the listed at-risk groups, but do not establish the comparative effect on PET activation. Overall, the registry supports describing the design, intended question, termination, and recorded safety counts. It does not support a conclusion about the primary endpoint's treatment comparison.
9. Statistical Methods Explained
Several statistical ideas help clarify what the registry record can and cannot establish. The points below distinguish general concepts from information specifically reported for this study.
What does non-randomized allocation imply?
In general, randomization uses a chance process to assign participants to groups. This can help balance measured and unmeasured characteristics between groups, though it does not guarantee perfect balance. In a non-randomized comparison, treatment assignment may be related to participant characteristics, clinical decisions, or other factors. A difference in outcomes can therefore reflect both treatment and differences between the groups.
For this study, allocation is listed as non-randomized, and the arm descriptions say that each group consisted of patients whose neurologist had prescribed the corresponding treatment. The registry does not report details about how prescriptions were made, what baseline characteristics were measured, or whether statistical adjustment was planned. Since the primary follow-up outcome is not reported, the record also does not allow assessment of whether the groups had comparable outcome trajectories.
What does a change-from-baseline measure represent?
In general, change from baseline uses a participant's initial measurement as a reference for a later measurement. A group summary can describe the average or another chosen summary of those changes. A comparative analysis can then contrast the summaries between groups. The choice of summary and model affects the interpretation, and those details are not reported for this endpoint.
The primary outcome is change from baseline in PET activation of PBR06 at 12 months. Its description identifies lesional and non-lesional NAWM and NAGM. The registry does not state the endpoint unit, the exact summary measure, or the statistical model. It also states that no subject had further data collected after the initial visit. Accordingly, there are no recorded 12-month changes in the primary outcome description to summarize.
How should uncertainty be understood?
In general, a statistical estimate is more informative when accompanied by an uncertainty measure, such as a confidence interval. A confidence interval represents uncertainty about the estimate under the model and assumptions used. A p-value addresses compatibility of data with a specified null hypothesis under a statistical model; it is not a measure of effect size or clinical importance. Neither type of statistic substitutes for the estimate itself.
The registry record does not report a primary endpoint estimate, confidence interval, or p-value. It lists no analyses. As a result, the primary endpoint's magnitude and statistical precision cannot be evaluated. This is not the same as a non-significant test or a confidence interval that includes no difference; those require outcome data and an analysis.
Why can unequal groups and over-dispersion matter?
In general, the amount of information in a comparison depends on the number of observations and how variable the measured outcomes are. Unequal group sizes can affect precision, particularly when one group is much smaller. Over-dispersion occurs when outcome variability is greater than a statistical model assumes; if not accounted for, standard errors may be too small and uncertainty may be understated. These are general considerations, not reported findings about this study. The registry does not provide a primary endpoint distribution or variance estimate with which to assess them.
The enrollment is listed as 8, and the safety record reports at-risk counts by arm. These counts are not a substitute for a primary-outcome analysis. The primary endpoint description states that no data were collected after the initial visit, and the registry does not report endpoint-specific denominators or a model for the planned comparison.
What do the planning assumptions mean?
The record describes a planning illustration based on an observed effect, with a two-sided significance level of 0.05, equal allocation, and a normal approximation. It says that the effect to detect is a stated fraction of the observed effect. In general, sample-size planning estimates describe how many participants might be needed under specified assumptions to detect an effect with a chosen statistical power. They are not evidence that the study achieved that power.
The record also specifies that time-to-event planning uses a total event count, while other planning quantities are expressed as participants per arm. No sample-size justification or actual power analysis is reported in the registry record. Because the primary outcome data are not available in the recorded follow-up, planning illustrations should not be interpreted as observed evidence of an effect or as a substitute for an outcome analysis.
What does a parallel-group comparison require?
In general, a parallel-group design measures separate groups receiving different interventions and compares their outcomes. A valid interpretation depends on consistent outcome measurement, adequate follow-up, and an analysis that accounts for the design and relevant sources of bias. A controlled design does not by itself eliminate confounding when allocation is not randomized.
The registry describes a parallel model and an active comparator, but does not report analysis details for the intended comparison. Its primary outcome record documents no follow-up after the initial visit. Consequently, the basic elements needed for a longitudinal comparison—recorded later measurements and a reported analysis—are not present in the registry record.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists 14 outcome measures, including secondary outcomes involving PET activation at follow-up times and the number of new ultrasmall superparamagnetic iron oxide particles. When a study evaluates multiple outcomes or time points, general statistical practice considers multiplicity: the more hypotheses examined, the greater the chance of at least one apparently unusual result arising by chance if each is tested separately. Methods to address this can include prespecifying a primary comparison or adjusting inference across tests. The registry record does not report a multiplicity strategy.
The record lists no analyses. It does not report whether interim analyses were planned or conducted, how missing outcome data would be handled, or which analysis populations were specified. Those details are not reported in the registry record, so no imputation, exclusion, or population definition should be assumed.
The primary outcome description states that the study was terminated and that no subject had further data collected after the initial visit. This identifies a major limitation for the intended 12-month endpoint, but the record does not describe why follow-up stopped or provide a detailed accounting of missingness by outcome. In general, missing data can affect validity when the likelihood of missingness is related to participant characteristics or outcomes. The registry does not provide information to determine such a relationship.
Because there are no reported primary outcome analyses, multiplicity adjustments, missing-data methods, and analysis populations cannot be evaluated from the record. The lack of a reported analysis is not a result from a completed statistical test.
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 |
|---|---|---|---|
| Ocrevus | 0 | 5 | 0.0% |
| Mayzent | 0 | 3 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Ocrevus | 0 of 5 |
| Mayzent | 0 of 3 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 1% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Ocrevus | 0 of 5 |
| Mayzent | 2 of 3 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Ocrevus | Mayzent |
|---|---|---|---|
| Allergic Reaction | Injury, poisoning and procedural complications | 0 of 5 | 2 of 3 |
The safety record reports serious adverse events for the Ocrevus group with 5 at risk and 0 affected, and for the Mayzent group with 3 at risk and 0 affected. It reports other adverse events for the Ocrevus group with 5 at risk and 0 affected, and for the Mayzent group with 3 at risk and 2 affected. Deaths are recorded as 0 in each group. No serious adverse event terms are listed.
These are counts for the groups and categories named in the registry. They should not be converted into percentages or treated as a complete account of safety beyond what the record reports. In general, a count of zero observed events does not establish that an event cannot occur; interpretation depends on the amount and duration of observation and on how events were collected. The registry's primary outcome description says there was no further data collection after the initial visit, but the safety entry does not explain its observation period or event-collection procedures.
The safety counts do not provide a statistical comparison of adverse-event risk. The record does not report uncertainty intervals, tests, or adjusted analyses for these counts. They should also be kept separate from the PET activation endpoint, which has no reported follow-up result.
12. What the Result Does, and Does Not, Mean
The registry record describes a prospective comparison intended to assess PET activation in patients with secondary-progressive multiple sclerosis treated with Mayzent, with Ocrevus as an active control. It identifies a 12-month change-from-baseline primary endpoint and a broader objective concerning microglial activation. These details explain the intended research question, not an observed treatment effect.
The record states that the study was terminated and that no subject had further data collected after the initial visit. It does not report a 12-month primary endpoint estimate or analysis. Therefore, the record cannot establish the direction, size, or precision of change in PET activation, nor whether the groups differed. Lack of a reported endpoint result is not evidence that the treatments had equal effects, and it is not evidence that either treatment changed the measured outcome.
The study was non-randomized. In general, comparisons in such designs may be influenced by differences between groups apart from treatment. The registry does not report adjustment methods or information sufficient to assess that issue. Even if follow-up results were available, a treatment comparison would need to be interpreted in light of the allocation process and analysis methods.
The safety record contains counts for serious and other adverse events and deaths, but it does not report inferential comparisons or a detailed observation period. These counts describe recorded events in the listed groups; they do not answer the primary imaging question.
Thus, the study record is informative about its intended design and the fact that longitudinal follow-up did not proceed as planned. It does not provide evidence from the stated primary endpoint with which to estimate comparative efficacy. No clinical recommendation follows from these registry entries.
13. Why This Trial Matters Statistically
This study matters statistically because its intended question depends on longitudinal measurements, while the registry record states that no subject had further data collected after the initial visit. That gap separates a planned endpoint from an analyzable endpoint. A study can specify a clinically interesting measurement and comparison, yet without later observations it cannot estimate the planned change from baseline.
The non-randomized design is also important. Patients entered groups according to prescriptions made by their neurologists. In general, this can create differences between groups that complicate causal interpretation. Statistical adjustment may sometimes address measured differences, but it cannot automatically remove unmeasured confounding. The registry does not describe an adjustment strategy, and no endpoint analysis is listed.
The record also illustrates why an active comparator and a controlled label do not, by themselves, establish a reliable treatment contrast. The comparison requires outcome data and a transparent account of how the groups and measurements were analyzed. Here, the primary outcome result and analysis are not reported.
Finally, the distinction between planning and observation is central. Planning illustrations rely on assumptions about an effect and an analysis; they do not show that the planned study collected enough information or achieved a specified power. They cannot replace observed outcome estimates. In this record, the most consequential statistical interpretation is therefore the boundary of what can be concluded: the study's question is documented, but the primary longitudinal comparison is not answered by the recorded data.
14. Limitations
- The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
- Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.
The registry identifies several limitations specific to this study. First, its primary endpoint requires a 12-month follow-up measurement, while the record states that no subject had further data collected after the initial visit. The primary outcome therefore has no reported longitudinal estimate.
Second, the study was non-randomized. The Mayzent and Ocrevus groups were based on prescriptions by neurologists, and the registry does not report the treatment-selection process or methods for controlling confounding. This limits the interpretation of any comparison, even apart from the missing follow-up.
Third, the registry does not provide the endpoint unit, summary parameter, statistical model, confidence interval, or p-value. It lists 14 outcome measures but does not report a multiplicity approach. Missing-data methods, analysis populations, interim analyses, and a detailed statistical analysis plan are also not reported in the registry record.
The record lists phase 2 and phase 3 and describes the study as open-label and single-blind, but does not explain the phase designations or identify who was blinded. It does not report the reason for termination or a sample-size justification. These omissions constrain assessment of the intended design and its implementation. The posted safety counts are limited to the event categories and at-risk groups recorded; the record does not describe their observation period or provide inferential safety analyses.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Study to Assess the Efficacy of Mayzent on Microglia in Secondary Progressive Multiple Sclerosis — NCT04925557.
- Registry record last updated 2025-05-13; status last verified 2025-04.
- Results first posted 2025-05-13.
- 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
The registry describes a prospective, longitudinal, controlled, observational, parallel-group study of Mayzent compared with Ocrevus in secondary-progressive multiple sclerosis. Allocation was non-randomized, with treatment prescribed by neurologists. The record lists phase 2 and phase 3, enrollment of 8, and State University of New York at Buffalo as sponsor.
The recorded start date is 2021-11-13, the primary completion date is 2023-06-01, and the status is terminated. The primary endpoint was change from baseline in PET activation at 12 months. The registry states that no subject had further data collected after the initial visit and lists no analyses. As a result, no primary endpoint estimate or comparative analysis is reported. Safety counts are recorded by group, but do not resolve the missing longitudinal endpoint.