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 of RoActemra/Actemra (Tocilizumab) in Combination With Methotrexate Versus RoActemra/Actemra Monotherapy in Patients With Rheumatoid Arthritis and an Inadequate Response to Methotrexate (NCT01399697), a randomized phase 4 study. The primary outcome is Change in Disease Activity Score Based on 28-Joint Count (DAS28) From Week 16 to Week 28.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01399697 |
| Phase | Phase 4 |
| Condition | Rheumatoid Arthritis |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Double |
| Enrollment | 261 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Hoffmann-La Roche |
| Results posted | Yes |
2. Clinical Question
Population
People with rheumatoid arthritis and an inadequate response to methotrexate were eligible for the study. All participants received tocilizumab with methotrexate for an initial 16 weeks. Only those achieving low disease activity at Week 16 were randomized for the subsequent comparison. The primary outcome population is defined as the intent-to-treat population: randomized participants who received at least one dose of study medication and had at least one efficacy measurement.
Intervention
After the initial treatment period, one randomized group continued tocilizumab with methotrexate for a further 12 weeks. The registry describes tocilizumab as 8 mg/kg intravenously every 4 weeks during the initial period; later dosing details are not reported in the registry record.
Comparator
The other randomized group continued tocilizumab with placebo in place of methotrexate for the further 12 weeks. Thus, the contrast concerns continuing methotrexate versus replacing it with placebo while tocilizumab treatment continues. The registry record does not provide fuller arm descriptions.
Primary question
The primary question is how disease activity, measured by change in DAS28 from Week 16 to Week 28, compares between the two randomized groups. The record gives the endpoint definition but does not report the numerical group results or a numerical between-group comparison.
This design addresses a treatment decision among participants who reached low disease activity during the initial combination-treatment period. It does not directly estimate the effect of starting with the two different regimens in everyone enrolled, because everyone first received tocilizumab with methotrexate and randomization occurred only after that period for those meeting the Week 16 criterion. The enrollment recorded for the study is 261; this is not a reported count of participants in either randomized group.
3. Trial Design
This was a phase 4, randomized, double-blind, parallel-group study with an enrollment of 261. It was sponsored by Hoffmann-La Roche and is recorded as completed. The registry lists a study start of 2011-09 and primary completion of 2014-05.
The treatment sequence matters for interpreting the comparison. All participants were to receive tocilizumab, also called RoActemra or Actemra, at 8 mg/kg intravenously every 4 weeks together with oral methotrexate for 16 weeks. At Week 16, participants achieving low disease activity were randomized to a further 12 weeks of tocilizumab treatment with either methotrexate or placebo. Anticipated time on study treatment was 28 weeks.
Consequently, the randomized comparison is a continuation-phase comparison in a selected group: participants had received the same initial combination and met the Week 16 low-disease-activity condition. It is not a direct randomized comparison of the two regimens from study entry. The registry identifies the study as double-blind but does not report details of how masking was maintained or which parties were masked. It also does not report the allocation procedure beyond identifying allocation as randomized.
Arm descriptions are blank in the record. The treatment sequence is described in the study summary and intervention listing, but further operational details, including adherence procedures and permitted concomitant treatment, are not reported in the registry record. The study lists rheumatoid arthritis as its condition and identifies nine outcome measures and nine analyses. The record does not supply a detailed analysis plan explaining how each outcome was handled.
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 | Tocilizumab (TCZ) Plus (+) Methotrexate (Not Randomized) | TCZ + MTX (Randomized) | TCZ + Placebo (Randomized) |
|---|---|---|---|
| STARTED | 96 | 83 | 82 |
| COMPLETED | 55 | 80 | 78 |
| NOT COMPLETED | 41 | 3 | 4 |
Reasons for not completing this period:
| Reason | Tocilizumab (TCZ) Plus (+) Methotrexate (Not Randomized) | TCZ + MTX (Randomized) | TCZ + Placebo (Randomized) |
|---|---|---|---|
| Adverse Event | 13 | 3 | 1 |
| Lost to Follow-up | 2 | 0 | 0 |
| Withdrawal by Subject | 8 | 0 | 0 |
| Investigator Decisión | 1 | 0 | 2 |
| Lack of Efficacy | 9 | 0 | 1 |
| Protocol Violation | 2 | 0 | 0 |
| Non-Compliant | 1 | 0 | 0 |
| Inclusion Error | 2 | 0 | 0 |
| Positive result for hepatitis B | 1 | 0 | 0 |
| Clinical RA remission | 1 | 0 | 0 |
| Sponsor Decision | 1 | 0 | 0 |
Analysis population for the primary outcome, as defined in the registry: Intent-to-treat (ITT) population: all randomized participants who received at least one dose of study medication and who had at least one efficacy measurement performed.
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: All treated population
| Characteristic | Unit | TCZ + MTX (Not Randomized) | TCZ + MTX (Randomized) | TCZ + Placebo (Randomized) | Total |
|---|---|---|---|---|---|
| Participants analysed | 96 | 83 | 82 | 261 | |
| Age, Continuous | years | 52.3 (SD 13.2) | 50.2 (SD 12.5) | 51.0 (SD 12.2) | 51.2 (SD 12.6) |
| Sex: Female, Male: Female | Participants | 76 | 62 | 65 | 203 |
| Sex: Female, Male: Male | Participants | 20 | 21 | 17 | 58 |
6. Primary Endpoint
The registry lists the primary outcome as Change in Disease Activity Score Based on 28-Joint Count (DAS28) From Week 16 to Week 28, measured over Baseline, Week 16, and Week 28.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Deviation |
| Unit | units on a scale |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is change in the Disease Activity Score based on 28 joint counts (DAS28) from Week 16 to Week 28. The registry describes the endpoint as a mean, with standard deviation as the dispersion measure, and gives the timeframe as baseline, Week 16, and Week 28. The endpoint’s stated comparison period is Week 16 to Week 28, following randomization.
DAS28 combines swollen and tender joint counts, an acute-phase response measured using erythrocyte sedimentation rate, and the participant’s global assessment of disease activity on a visual analogue scale. It uses a 28-joint count rather than the 44-swollen-joint count of the original DAS. The scale ranges from 0 to 10, with higher scores indicating greater disease activity.
As a combined measure, DAS28 brings information from joint examination, an inflammatory marker, and a participant assessment into one disease-activity score. General statistical context: a change score describes how a measurement differs between specified assessments; the direction and size of a group’s change can be useful descriptively, while a randomized between-group contrast is needed to address the treatment comparison. The registry record does not report the group means, standard deviations, or the estimated between-group difference for this endpoint. It therefore does not support a numerical account of the primary result.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies the primary outcome and the intended randomized comparison, but it does not report the numerical primary endpoint results. The change in mean DAS28 between Week 16 and Week 28 for either group, the between-group estimate, its uncertainty, and a p-value are not reported in the registry record. The direction, magnitude, and precision of the primary comparison therefore cannot be assessed from this record.
The timing and eligibility condition define what the comparison can address. Every participant first received tocilizumab with methotrexate. Randomization to continue methotrexate or take placebo occurred only among those achieving low disease activity at Week 16. The randomized contrast therefore concerns continuation of methotrexate in this post-induction group, not the effect of choosing one regimen at initial treatment for all participants with an inadequate response.
General statistical context: the estimate of a treatment contrast is most informative when considered alongside its confidence interval. A confidence interval conveys a range of values compatible with the data under the analysis assumptions; a narrow interval indicates greater precision than a wide interval. Neither an interval nor a p-value alone establishes clinical importance. Clinical interpretation also depends on the magnitude and direction of the estimate and on the outcome’s meaning. These quantities are not reported for the primary endpoint in the registry record.
The outcome list includes other measures of disease activity, disability, quality of life, and global assessment at or across specified time points. Their presence describes the breadth of measurement, but their existence does not fill the gap in the primary result. Numerical estimates and uncertainty for these secondary outcomes are not included in the record’s details. Their reported results, if any, are not available in the registry record described for this analysis.
There is also no basis in the record for claiming that the treatment regimens differed, were equivalent, or had no meaningful difference on DAS28. Failure to report an estimate is not evidence of no effect. It means that readers cannot determine the observed primary comparison or how precisely it was estimated using this record alone.
9. Statistical Methods Explained
The registry identifies a mean change in DAS28 as the primary endpoint and standard deviation as the dispersion measure. It does not report the detailed statistical methods used to estimate or compare that outcome. The points below explain relevant statistical concepts in general; they should not be read as claims about methods actually used in this study.
What does a mean change describe?
General statistical context: a mean summarizes the average observed value in a group. For a change endpoint, each participant’s value is based on assessments at the specified times, and a group mean summarizes those changes. The between-group comparison is a separate quantity: it contrasts the group summaries and is the quantity directly relevant to the randomized treatment question. A within-group mean change alone does not establish that one regimen differs from the other.
The registry specifies change from Week 16 to Week 28, while the endpoint timeframe also lists baseline. Baseline and Week 16 assessments can describe the broader course of measurement, but the named primary change period begins at Week 16. The method used to incorporate baseline or other repeated measurements is not reported in the registry record.
What does standard deviation convey?
General statistical context: standard deviation describes the spread of participant measurements around a group mean. It is not the same as the standard error, which describes the estimated precision of a mean, and it is not a confidence interval. A group can have a clearly defined mean yet substantial variation among participants. The record identifies standard deviation as the dispersion measure but does not give its value for the primary outcome.
Why are confidence intervals useful?
General statistical context: a confidence interval presents uncertainty around an estimated quantity under specified assumptions. For a between-group estimate, it helps readers assess which effect sizes are compatible with the data, rather than relying only on whether a significance threshold was crossed. The width depends on the amount and variability of information and on the analysis. The confidence interval for the primary contrast is not reported in the registry record.
What can randomization contribute?
General statistical context: random allocation is intended to make treatment groups comparable on average with respect to measured and unmeasured baseline characteristics, reducing confounding in the comparison. It does not guarantee identical groups in a particular study, and it does not remove issues such as missing outcome measurements or departures from assigned treatment. Here, randomization applies to the continuation comparison among participants who achieved low disease activity at Week 16, not to the initial treatment period.
The record labels the study double-blind. General statistical context: masking can reduce the risk that knowledge of assignment influences care, reporting, or outcome assessment. The registry does not describe who was masked, the masking procedure, or whether masking was assessed, so those details cannot be evaluated.
Why might variability affect precision?
General statistical context: when outcome values vary substantially among participants, a mean comparison may be estimated less precisely than when values are more alike, given otherwise similar study information. Some count or rate outcomes can have greater variability than a simple model assumes; over-dispersion means the observed variability exceeds the model’s expected variability. It can make standard errors too small if ignored. This primary endpoint is a continuous score, and the registry does not report whether over-dispersion or any alternative variance model was assessed.
What do the planning illustrations represent?
The record describes planning illustrations based on the observed effect, a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. It states that the effect to detect is a stated fraction of the observed effect. These are described as planning illustrations, not as the trial’s own design justification. No numerical illustration values or detailed sample-size justification are reported in the registry record. Such illustrations are not observed power and do not establish the probability that the trial detected an effect.
Which analysis details remain unknown?
The record does not report the model used for the primary comparison, adjustment variables, standard-error method, confidence-interval method, significance threshold for the primary analysis, or handling of repeated observations. It does define an intent-to-treat population as randomized participants who received at least one dose and had at least one efficacy measurement. This definition is narrower than a population containing every randomized participant regardless of treatment received or outcome availability. These omissions limit reproducibility and make it impossible to assess how analysis choices may affect the primary estimate.
10. Multiplicity, Missing Data and Analysis Populations
The study lists nine outcome measures and nine analyses. The primary outcome is the change in DAS28 from Week 16 to Week 28; the listed secondary outcomes include disease-activity thresholds using DAS28, CDAI, and SDAI, as well as changes in disability, mental and physical health, and participant- and investigator-rated global disease activity. Multiple outcomes can create multiple opportunities to observe apparently notable results. General statistical context: multiplicity procedures may control the chance of false-positive conclusions across a family of tests, but the registry record does not report whether any such procedure was planned or used.
The registry’s outcome note indicates that the primary outcome has several categories or time points and was not reduced to one comparison. Consequently, the record does not furnish a single numerical primary comparison for interpretation. The detailed hierarchy of analyses, any prespecified contrasts, and whether the secondary outcomes were confirmatory or exploratory are not reported in the registry record.
The primary analysis population is described as the intent-to-treat population, consisting of randomized participants who received at least one dose of study medication and had at least one efficacy measurement. The record does not report how many participants met this definition or how many were included in each endpoint analysis. It also does not describe reasons for missing measurements, the amount or pattern of missingness, or any imputation or other missing-data method. General statistical context: missing-data assumptions can influence estimates, particularly when the likelihood of an unavailable measurement relates to participants’ health or outcomes. Without the missingness and analysis details, the robustness of the primary result cannot be assessed.
Details of interim analyses, stopping rules, and a complete statistical analysis plan are not reported in the registry record. They should not be inferred from the phase, design, or enrollment information.
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 |
|---|---|---|---|
| TCZ + MTX (Not Randomized) | 11 | 96 | 11.5% |
| TCZ + MTX (Pre-randomization) | 0 | 83 | 0.0% |
| TCZ + Placebo (Pre-randomization) | 1 | 82 | 1.2% |
| TCZ + MTX (Post-randomization) | 1 | 83 | 1.2% |
| TCZ + Placebo (Post-randomization) | 4 | 82 | 4.9% |
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 |
|---|---|
| TCZ + MTX (Not Randomized) | 28 of 96 |
| TCZ + MTX (Pre-randomization) | 20 of 83 |
| TCZ + Placebo (Pre-randomization) | 24 of 82 |
| TCZ + MTX (Post-randomization) | 8 of 83 |
| TCZ + Placebo (Post-randomization) | 4 of 82 |
Most frequent serious adverse event terms
| Event term | Organ system | TCZ + MTX (Not Randomized) | TCZ + MTX (Pre-randomization) | TCZ + Placebo (Pre-randomization) | TCZ + MTX (Post-randomization) | TCZ + Placebo (Post-randomization) |
|---|---|---|---|---|---|---|
| Hypertransaminasaemia | Hepatobiliary disorders | 3 of 96 | 0 of 83 | 0 of 82 | 0 of 83 | 0 of 82 |
| Pneumonia | Infections and infestations | 1 of 96 | 0 of 83 | 0 of 82 | 0 of 83 | 1 of 82 |
| Deep vein thrombosis | Vascular disorders | 2 of 96 | 0 of 83 | 0 of 82 | 0 of 83 | 0 of 82 |
| Vertigo | Ear and labyrinth disorders | 0 of 96 | 0 of 83 | 0 of 82 | 0 of 83 | 1 of 82 |
| Chest Pain | General disorders | 1 of 96 | 0 of 83 | 0 of 82 | 0 of 83 | 0 of 82 |
| Bursitis infective | Infections and infestations | 0 of 96 | 0 of 83 | 0 of 82 | 0 of 83 | 1 of 82 |
| Endocarditis bacterial | Infections and infestations | 0 of 96 | 0 of 83 | 0 of 82 | 1 of 83 | 0 of 82 |
| Staphylococcal skin infection | Infections and infestations | 0 of 96 | 0 of 83 | 0 of 82 | 0 of 83 | 1 of 82 |
| Cytomegalovirus infection | Infections and infestations | 1 of 96 | 0 of 83 | 0 of 82 | 0 of 83 | 0 of 82 |
| Herpes zoster | Infections and infestations | 1 of 96 | 0 of 83 | 0 of 82 | 0 of 83 | 0 of 82 |
Most frequent non-serious adverse event terms
| Event term | Organ system | TCZ + MTX (Not Randomized) | TCZ + MTX (Pre-randomization) | TCZ + Placebo (Pre-randomization) | TCZ + MTX (Post-randomization) | TCZ + Placebo (Post-randomization) |
|---|---|---|---|---|---|---|
| Hypertransaminasaemia | Hepatobiliary disorders | 15 of 96 | 12 of 83 | 10 of 82 | 8 of 83 | 4 of 82 |
| Hypercholesterolaemia | Metabolism and nutrition disorders | 9 of 96 | 2 of 83 | 6 of 82 | 0 of 83 | 0 of 82 |
| Aphthous stomatitis | Gastrointestinal disorders | 0 of 96 | 3 of 83 | 6 of 82 | 0 of 83 | 0 of 82 |
| Urinary tract infection | Infections and infestations | 0 of 96 | 3 of 83 | 5 of 82 | 0 of 83 | 0 of 82 |
| Leukopenia | Blood and lymphatic system disorders | 7 of 96 | 0 of 83 | 0 of 82 | 0 of 83 | 0 of 82 |
| Neutropenia | Blood and lymphatic system disorders | 7 of 96 | 0 of 83 | 0 of 82 | 0 of 83 | 0 of 82 |
| Respiratory tract infection | Infections and infestations | 5 of 96 | 0 of 83 | 0 of 82 | 0 of 83 | 0 of 82 |
Serious events with the highest arm-level rate: hypertransaminasaemia (3.1%), deep vein thrombosis (2.1%), vertigo (1.2%), bursitis infective (1.2%), pneumonia (1.2%).
The registry lists serious and other adverse-event counts for several treatment-period groups. For the group labelled TCZ + MTX (Not Randomized), the serious adverse-event count is 11 among 96 at risk, and the other adverse-event count is 28 among 96 at risk. For the pre-randomization groups, the corresponding serious and other counts are 0 and 20 among 83 at risk for TCZ + MTX, and 1 and 24 among 82 at risk for TCZ + Placebo. For the post-randomization groups, the counts are 1 and 8 among 83 at risk for TCZ + MTX, and 4 and 4 among 82 at risk for TCZ + Placebo.
These are counts within the registry’s named groups, not treatment-effect estimates. The group labels distinguish pre-randomization and post-randomization periods, so the figures should be read in their stated context rather than combined across groups. The record does not report deaths for these groups; the death entries are not reported in the registry record.
The listed serious adverse-event terms include hypertransaminasaemia (3.1%), deep vein thrombosis (2.1%), vertigo (1.2%), infective bursitis (1.2%), pneumonia (1.2%), and staphylococcal skin infection (1.2%). The record does not specify in this listing how those term percentages relate to the group-specific counts. These figures alone do not establish comparative risk or causation.
12. What the Result Does, and Does Not, Mean
The study’s central statistical question is a randomized comparison of continuing methotrexate versus using placebo alongside ongoing tocilizumab after an initial combination-treatment period. The design focuses on participants who achieved low disease activity by Week 16. That eligibility condition is essential to interpreting the target population: the comparison does not directly represent everyone with rheumatoid arthritis and an inadequate response to methotrexate at study entry.
The primary measure, DAS28, combines joint counts, an acute-phase response, and participant assessment into a score for rheumatoid arthritis disease activity. Change in the score from Week 16 to Week 28 is the stated primary endpoint. However, the numerical endpoint results and uncertainty are not reported in the registry record. As a result, the record does not show the estimated difference between the randomized groups, its precision, or whether the estimate might be clinically important.
General statistical context: a statistically detectable difference, if reported, would not by itself establish that the difference matters to participants. Conversely, an imprecise estimate that is not statistically distinguishable from no difference would not prove that the regimens are equivalent. Equivalence or non-inferiority requires a suitable design and prespecified margins; those details are not reported in the registry record.
The listed secondary outcomes broaden the assessment to other disease-activity measures, disability, quality of life, and global assessments. Their presence indicates that the study considered more than one aspect of outcome, but the record does not give numerical results for those measures in the registry record for this analysis. The safety counts are descriptive and do not by themselves support a causal or comparative conclusion.
Accordingly, the registry record supports an account of the study question, treatment sequence, outcome definitions, and some adverse-event counts. It does not support a conclusion about the magnitude or direction of the primary treatment comparison. The absence of reported estimates should not be interpreted as evidence that the groups had the same outcome, nor as evidence that they differed.
13. Why This Trial Matters Statistically
This study is statistically instructive because its treatment comparison occurs after a shared initial treatment period. All participants were to receive tocilizumab with methotrexate for 16 weeks, and randomization for the continuation phase was conditional on achieving low disease activity at Week 16. The distinction between the entry population and the randomized population determines how broadly the randomized result could be generalized.
The study also illustrates why an endpoint definition is not the same as a result. DAS28 is described in detail, including its component measures, scale, and direction, and the primary change period is identified. Yet without the group estimates and an uncertainty measure, readers cannot evaluate the primary contrast. A complete statistical interpretation needs the estimate as well as its precision.
The nine listed outcome measures span disease activity, function, quality of life, and global assessment. This range can provide complementary information, but it raises questions about analysis hierarchy and multiplicity. The registry record does not report how those questions were addressed. Nor does it report missing-data methods, the specific primary comparison model, or the numerical planning illustrations described as based on the observed effect.
Finally, the adverse-event entries distinguish non-randomized, pre-randomization, and post-randomization groups. Keeping those contexts separate is necessary when reading the counts; they are not interchangeable measures of comparative treatment risk. The record is therefore useful for understanding the design and the limits of the available evidence, while leaving the principal efficacy estimate unresolved.
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 principal limitation for statistical interpretation is that numerical results for the primary endpoint are not reported in the registry record. There is no reported group mean change, between-group estimate, confidence interval, or p-value for the Week 16 to Week 28 DAS28 comparison. The primary treatment effect and its precision cannot be evaluated.
The randomized population is conditional on achieving low disease activity at Week 16 after a shared initial course of tocilizumab with methotrexate. This design limits the target of the comparison to that continuation-phase population. The enrollment of 261 does not identify the number randomized or the number included in the primary analysis.
The registry defines an intent-to-treat analysis population using receipt of at least one dose and at least one efficacy measurement. It does not give the group-specific analysis counts or explain exclusions from the randomized population. Missing outcome patterns, reasons for missingness, and methods for handling missing data are not reported.
Further limitations arise from unreported analysis details. The statistical model, adjustment strategy, confidence-interval method, multiplicity approach, and complete analysis hierarchy are not reported in the registry record. The endpoint timeframe includes baseline, but the role of baseline in the primary analysis is not specified. Detailed masking procedures and allocation methods are also not given.
Safety counts are presented for groups defined by treatment period, but the record does not provide a comparative analysis or explain the relationship between the listed term percentages and group-specific counts. Deaths are not reported in the registry record. These gaps preclude a complete assessment of efficacy, safety comparisons, and analysis robustness from the registry information alone.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: A Study of RoActemra/Actemra (Tocilizumab) in Combination With Methotrexate Versus RoActemra/Actemra Monotherapy in Patients With Rheumatoid Arthritis and an Inadequate Response to Methotrexate — NCT01399697.
- Registry record last updated 2015-07-13; status last verified 2015-05.
- Results first posted 2015-07-13.
- 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.
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18. Record Summary
NCT01399697 is a completed phase 4 randomized, double-blind, parallel-group study sponsored by Hoffmann-La Roche. It enrolled 261 participants and studied rheumatoid arthritis with an inadequate response to methotrexate. All participants were to receive tocilizumab with methotrexate for 16 weeks; those achieving low disease activity at Week 16 were randomized to a further 12 weeks of tocilizumab with either methotrexate or placebo.
The primary endpoint was change in DAS28 from Week 16 to Week 28, with the mean and standard deviation specified. The registry describes the score and identifies the intent-to-treat population, but numerical primary results and their uncertainty are not reported in the registry record. The record lists nine outcomes and adverse-event counts across treatment-period groups. It does not report a detailed statistical plan, missing-data methods, or a multiplicity approach.