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 AC105 in Patients With Acute Traumatic Spinal Cord Injury (NCT01750684), a randomized phase 2 study. The primary outcome is Number of Participants With Treatment-related Adverse Events as Assessed by CTCAE v4.0.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01750684 |
| Phase | Phase 2 |
| Condition | Acute Spinal Cord Injury |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Triple |
| Enrollment | 15 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Acorda Therapeutics |
| Results posted | Yes |
2. Clinical Question
Population
Participants with acute traumatic spinal cord injury. The registry record lists Acute Spinal Cord Injury as the condition and reports enrollment of 15 participants. The primary endpoint population is identified as the Safety Population. The record does not provide additional eligibility details in the information reported for this trial, so the clinical question is limited to this registered population rather than a more narrowly defined injury subgroup.
Intervention
AC105, administered as an initial 30-minute intravenous infusion within a pre-specified time window of 12, 9, or 6 hours post-injury, followed by 5 additional infusions of the same dose and duration at 6-hour intervals. The official title describes a regimen of 6 doses over 30 hours. The principal aim was to establish the feasibility of rapid administration, safety, and tolerability, and to assess potential activity.
Comparator
Saline placebo, administered as an initial 30-minute intravenous infusion within a pre-specified time window of 12, 9, or 6 hours post-injury, followed by 5 additional infusions at 6-hour intervals. The registry describes randomization between the placebo and active-drug arms at a 1:1 ratio. The record does not give further detail about how the timing window was assigned.
Primary question
The primary endpoint asks how many participants had treatment-related adverse events, assessed using CTCAE v4.0, over the stated timeframe of up to 6 months. The endpoint description also defines treatment-emergent adverse events by their timing relative to the first and last infusions. The record’s principal aim emphasizes rapid administration, safety and tolerability; it does not provide a single posted comparison of the primary endpoint between the randomized arms.
In statistical terms, this is a safety-focused early-phase question in a small randomized study. The study also included a secondary pharmacokinetic objective using individual patient plasma concentration-time data. That objective concerns drug exposure and is distinct from the primary adverse-event question. The registry record does not report a numerical result for the pharmacokinetic outcome or a formal estimate of AC105’s effect on clinical recovery.
3. Trial Design
This was a phase 2, randomized, triple-masked, parallel-group, placebo-controlled study of AC105 in participants with acute traumatic spinal cord injury. A parallel-group design assigns participants to one study arm, with each participant receiving the assigned regimen rather than crossing between study treatments. The registry describes the allocation as 1:1. Triple masking is listed, but the record does not specify which groups of people were masked or how masking was maintained.
The AC105 and saline arms followed matching infusion schedules as described in the record: an initial intravenous infusion lasting 30 minutes, given within a pre-specified post-injury timing window, and 5 additional infusions of the same dose and duration at 6-hour intervals. The official title characterizes the regimen as 6 doses over 30 hours. The stated timing options were 12, 9, or 6 hours post-injury. The registry does not report further operational details about the timing options or the dose amount.
The record reports enrollment of 15 participants. The safety figures list 6 participants at risk in the placebo group and 7 in the AC105 group. Those group counts are the denominators attached to the posted safety summaries; they should not be treated as a complete accounting of every enrolled participant without additional information. The record identifies the primary endpoint population as the Safety Population but does not describe other analysis populations.
The study began in 2013-07, and primary completion is recorded as 2015-02. Its status is Terminated. The reason for termination is not reported in the registry record, so the status alone does not establish why the study ended or whether the planned enrollment was reached. The registry identifies Acorda Therapeutics as sponsor. It lists two outcome measures and no analyses, and does not provide a single primary-outcome treatment comparison.
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 | Placebo | AC105 |
|---|---|---|
| STARTED | 6 | 7 |
| COMPLETED | 4 | 5 |
| NOT COMPLETED | 2 | 2 |
Reasons for not completing this period:
| Reason | Placebo | AC105 |
|---|---|---|
| Death | 1 | 0 |
| Non-compliance with Study Drug | 0 | 1 |
| Withdrawn by Sponsor | 0 | 1 |
| Protocol Violation | 1 | 0 |
Analysis population for the primary outcome, as defined in the registry: Safety Population
5. Baseline Characteristics
The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.
Population: Safety Population
| Characteristic | Unit | Placebo | AC105 | Total |
|---|---|---|---|---|
| Participants analysed | 6 | 7 | 13 | |
| Age, Continuous | years | 37.0 (SD 7.12) | 38.3 (SD 6.23) | 37.7 (SD 4.50) |
| Sex: Female, Male: Female | Participants | 1 | 1 | 2 |
| Sex: Female, Male: Male | Participants | 5 | 6 | 11 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 1 | 0 | 1 |
| Race (NIH/OMB): Asian | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Black or African American | Participants | 0 | 2 | 2 |
| Race (NIH/OMB): White | Participants | 5 | 5 | 10 |
| Race (NIH/OMB): More than one race | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 | 0 | 0 |
6. Primary Endpoint
The registry lists the primary outcome as Number of Participants With Treatment-related Adverse Events as Assessed by CTCAE v4.0, measured over up to 6 months.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | participants |
| Endpoint classification | Binary Endpoint |
The registered primary endpoint is the number of participants with treatment-related adverse events, assessed using CTCAE v4.0, with a timeframe of up to 6 months. A count of participants with an event is a safety measure: it records how many people experienced an event rather than how many separate event episodes occurred. This kind of endpoint is used to describe the observed safety experience during a study and to support assessment of tolerability.
The endpoint description defines treatment-emergent adverse events as events whose onset, or worsening, occurred on or after the first infusion and no more than 30 days after the last infusion. Treatment-emergent describes the timing of an event; it does not by itself establish that the study treatment caused it. The endpoint title uses the narrower phrase treatment-related adverse events, while the description supplies a timing definition for treatment-emergent adverse events. The registry record does not provide further detail on how relatedness was judged or how these terms were reconciled for the reported endpoint.
The posted material does not give a single numerical result for this primary endpoint or a direct arm-to-arm estimate. The registry indicates that the primary outcome has several categories or time points and is not reduced to one comparison. As a result, the safety counts available for interpretation should not be presented as a complete primary-endpoint analysis. They describe selected serious and other adverse-event summaries, not a reported estimate of the primary endpoint’s treatment contrast.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record describes a randomized comparison of AC105 with saline placebo in acute traumatic spinal cord injury, with safety and feasibility as central aims. It reports enrollment of 15 participants and provides adverse-event summaries for 6 participants at risk in the placebo group and 7 in the AC105 group. These counts define the denominators for the posted safety figures; the record does not explain the difference between these group counts and total enrollment.
For serious adverse events, the record reports 1 affected participant among 6 at risk in the placebo group and 2 among 7 at risk in the AC105 group. It reports 4 participants with other adverse events among 6 at risk in the placebo group and 6 among 7 at risk in the AC105 group. These are descriptive counts. The record does not provide uncertainty intervals or a formal statistical comparison for these summaries, so they do not establish whether the observed differences are compatible with chance variation or reflect a treatment effect.
The death counts are 1 in the placebo group and 0 in the AC105 group. These small counts should be read only as the events reported in this study. They do not, by themselves, show that either regimen changes the risk of death. Likewise, the serious-event term percentages listed in the record describe the reported terms but are not accompanied by an arm-specific breakdown in the information. They should not be interpreted as comparative risks.
The primary endpoint is the number of participants with treatment-related adverse events assessed using CTCAE v4.0. Although the record defines treatment-emergent events by their timing around infusion, it does not provide one summarized primary-outcome comparison. The record explicitly notes that the primary outcome has several categories or time points and is not reduced to one comparison. It lists no analyses. Therefore, the arm-level serious and other adverse-event figures are not a substitute for the missing primary-endpoint analysis.
The trial’s stated aim includes feasibility of rapid administration and safety and tolerability; it also refers to potential activity. The registry lists a secondary pharmacokinetic outcome based on individual patient plasma concentration-time data, but does not report a numerical pharmacokinetic result in the record details. No clinical efficacy estimate is posted. Consequently, the information supports a description of the reported safety counts and trial design, not a conclusion about clinical benefit or lack of benefit.
Precision is a central concern in interpreting a study with small reported arm denominators. In general, estimates based on few participants are sensitive to the outcomes of individual participants and can be imprecise. No confidence intervals or other uncertainty measures for these adverse-event counts are reported. The absence of such measures means the size and precision of any between-group difference cannot be assessed from the posted summaries. The appropriate statistical reading is descriptive and cautious: the counts record what was observed in the listed safety groups, while important comparative and uncertainty information is not reported in the registry record.
9. Statistical Methods Explained
Randomization is intended to create groups whose treatment assignments are determined by chance. In general, random assignment can reduce systematic differences between groups at the start of a study, although it does not ensure that groups will be alike in every characteristic, especially in a small study. This record identifies the study as randomized and gives a 1:1 allocation description. It does not report the randomization sequence method, any stratification factors, or implementation details.
What does triple masking tell readers?
The registry labels the study triple-masked. In general, masking is intended to limit the influence of treatment knowledge on participant experience, care, assessment, or reporting. The precise parties included in the masking label can vary across records. Which parties were masked, how masking was maintained, and whether masking was assessed are not reported in the registry record. The placebo comparator and matching infusion schedules are described, but the record does not establish from those details alone how successfully treatment assignment remained concealed.
How should the safety counts be understood?
The posted serious and other adverse-event summaries are counts of participants with events, alongside the numbers at risk in each group. In general, a participant count answers how many people experienced at least one event in a defined category; it is different from a count of all event episodes. A person may experience more than one event, but these summaries do not give event-level totals or details about repeated events. The posted safety summaries do not include confidence intervals or a formal test, so they are descriptive rather than a complete comparative analysis.
For a binary outcome such as whether a participant experienced an event, an arm-level proportion is often used to describe frequency. No proportions should be inferred from the posted participant counts for this interpretation; the registry figures are stated as counts and denominators. In general, a confidence interval communicates uncertainty around an estimate: it gives a range of values compatible with the data and the method used, under the method’s assumptions. No confidence interval for the adverse-event summaries is reported, so their statistical precision cannot be read directly from the record.
Why does a small study make uncertainty important?
In general, when the number of participants is small, each observed outcome can have a substantial influence on a group summary. This can make estimates unstable and leave wide uncertainty, even when a difference between groups appears visible in raw counts. Randomization does not remove this issue. The record reports 15 enrolled participants, with the listed safety groups containing 6 and 7 participants at risk. No formal estimate of the treatment contrast is posted in the registry record, so the posted counts cannot establish the magnitude or precision of a comparative effect.
Statistical tests and interval estimates also depend on the analysis actually performed and on its assumptions. The registry record lists no analyses for the outcome information at issue. It does not report a statistical model, a test, covariate adjustment, or an approach to multiplicity for the primary endpoint. General statistical methods can explain why these details matter, but they cannot be used to reconstruct an unreported analysis.
What does the record say about the primary endpoint?
The registered primary outcome is a count of participants with treatment-related adverse events, assessed by CTCAE v4.0. The record also notes that the primary outcome has several categories or time points and is not reduced to one comparison. This means there is no single posted primary-outcome contrast to interpret. The adverse-event summaries elsewhere in the record cover serious events, other events, and deaths, but the record does not state that these summaries constitute the complete primary-endpoint analysis.
General guidance for interpreting multiple outcomes is that the number of comparisons and the analysis plan can affect how statistical evidence is assessed. If many outcomes or time points are considered, the interpretation may depend on whether analyses were prespecified and whether any adjustment or prioritization was planned. The registry record does not report these details. It would therefore be inappropriate to assume that a particular multiplicity procedure was used or to treat any single listed safety count as a prespecified confirmatory test.
What are sample-size illustrations?
Any sample-size values associated with planning illustrations are not observed results and are not evidence that the trial had a particular probability of detecting an effect. The record describes its planning illustration as based on the observed effect, with a two-sided significance level of 0.05, equal allocation, and a normal approximation; the effect to detect is expressed as a stated fraction of the observed effect. Such calculations are hypothetical planning exercises. They do not describe the number of participants actually enrolled and are not observed power.
In general, a planning calculation depends on assumptions about the effect, variability or event frequency, significance level, allocation, and chosen analysis. It should not be interpreted as a justification used to design a study unless the record says it was part of the original design plan. Whether the trial’s original sample size was justified, whether interim analyses were planned, and whether a formal statistical analysis plan was used are not reported in the registry record.
How should missing information be handled?
The record identifies the Safety Population for the primary endpoint, but does not report a fuller definition of that population or explain how participants with incomplete safety follow-up were handled. It does not report missing-data methods, censoring rules, or sensitivity analyses for the primary endpoint. In general, missingness can affect interpretation when participants have unequal follow-up or when outcome availability is related to treatment or health status. Without the number and pattern of missing observations and the analysis approach, the potential effect of missing data cannot be assessed.
10. Multiplicity, Missing Data and Analysis Populations
The registry record lists two outcome measures and identifies the number of analyses as 0. The primary outcome is described as having several categories or time points and is not reduced to one comparison. A single primary-endpoint estimate, its uncertainty, and an associated statistical test are therefore not reported in the record. The secondary outcome concerns pharmacokinetic parameters using individual patient plasma concentration-time data; a numerical result for that outcome is not reported in the record details.
Multiplicity refers, in general, to the interpretive issue created when several outcomes, time points, groups, or statistical tests are considered. The evidence needed to understand how this was handled—such as a prespecified testing hierarchy or an adjustment method—is not reported in the registry record. No particular multiplicity strategy should be inferred from the study’s phase or from its list of outcomes.
The primary endpoint population is named as the Safety Population, but its detailed definition is not reported. The record does not explain the handling of participants with missing outcome information, incomplete follow-up, or deviations from the infusion schedule. It does not report imputation, censoring, or sensitivity-analysis methods. The adverse-event denominators are given for the safety summaries, but the record does not explain how those denominators relate to all enrolled participants.
These omissions limit assessment of how complete the analysis was and how robust any comparative result might be. They do not establish that missing data or multiplicity were mishandled; they mean the relevant procedures are not reported in the registry record.
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 |
|---|---|---|---|
| Placebo | 1 | 6 | 16.7% |
| AC105 | 2 | 7 | 28.6% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Placebo | 1 of 6 |
| AC105 | 0 of 7 |
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 |
|---|---|
| Placebo | 4 of 6 |
| AC105 | 6 of 7 |
Most frequent serious adverse event terms
| Event term | Organ system | Placebo | AC105 |
|---|---|---|---|
| Pneumonia | Infections and infestations | 0 of 6 | 2 of 7 |
| Wound dehiscence | Injury, poisoning and procedural complications | 1 of 6 | 0 of 7 |
| Pleural effusion | Respiratory, thoracic and mediastinal disorders | 0 of 6 | 1 of 7 |
| Respiratory arrest | Respiratory, thoracic and mediastinal disorders | 1 of 6 | 0 of 7 |
| Respiratory failure | Respiratory, thoracic and mediastinal disorders | 1 of 6 | 0 of 7 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Placebo | AC105 |
|---|---|---|---|
| Nausea | Gastrointestinal disorders | 2 of 6 | 4 of 7 |
| Anxiety | Psychiatric disorders | 2 of 6 | 3 of 7 |
| Pneumonia | Infections and infestations | 2 of 6 | 3 of 7 |
| Depression | Psychiatric disorders | 3 of 6 | 2 of 7 |
| Hypotension | Vascular disorders | 2 of 6 | 2 of 7 |
| Neuralgia | Nervous system disorders | 2 of 6 | 2 of 7 |
| Urinary tract infection | Infections and infestations | 1 of 6 | 2 of 7 |
| Ileus | Gastrointestinal disorders | 0 of 6 | 2 of 7 |
| Insomnia | Psychiatric disorders | 0 of 6 | 2 of 7 |
| Oxygen saturation decreased | Investigations | 0 of 6 | 2 of 7 |
Serious events with the highest arm-level rate: pneumonia (28.6%), wound dehiscence (16.7%), respiratory arrest (16.7%), respiratory failure (16.7%), pleural effusion (14.3%).
The serious adverse-event summaries report 1 affected participant among 6 at risk in the placebo group and 2 among 7 at risk in the AC105 group. The other adverse-event summaries report 4 affected participants among 6 at risk in the placebo group and 6 among 7 at risk in the AC105 group. The death counts are 1 for placebo and 0 for AC105. These figures are counts of participants in the reported safety groups, not counts of every event episode.
The record also lists serious-event terms with percentages: Pneumonia, 28.6%; Wound dehiscence, 16.7%; Respiratory arrest, 16.7%; Respiratory failure, 16.7%; and Pleural effusion, 14.3%. The record information does not identify these terms by treatment arm or provide enough detail to establish their denominator or whether participants could contribute to more than one term. They should therefore be read as listed serious-event terms, not as an arm-to-arm comparison.
In general, safety counts describe events observed during the specified study experience; they do not by themselves demonstrate causation. The endpoint title refers to treatment-related events, while the description defines treatment-emergent timing. These concepts are not interchangeable: an event occurring after treatment begins is not automatically caused by treatment. No formal comparative analysis or uncertainty interval for the posted safety counts is reported in the registry record.
12. What the Result Does, and Does Not, Mean
The registry record establishes that a randomized, triple-masked, placebo-controlled phase 2 study of AC105 was conducted in participants with acute traumatic spinal cord injury. It describes an infusion regimen and reports safety counts for the placebo and AC105 groups. Those counts are useful as a record of what was observed in the listed safety populations, but the record does not provide a single primary-outcome comparison or measures of statistical uncertainty for the reported group summaries.
The findings do not establish that AC105 caused the reported adverse events, nor do they show that the observed differences between groups are statistically reliable. Treatment-emergent events are defined by when they began or worsened relative to infusion; that timing definition does not establish treatment causation. The record does not report a full account of relatedness assessment or a formal analysis comparing the arms.
The study’s aims included feasibility of rapid administration, safety, tolerability, and potential activity. The posted information does not give a numerical result for feasibility, a complete primary-endpoint analysis, a clinical efficacy estimate, or a numerical pharmacokinetic result. The absence of these results in the registry record should not be converted into a conclusion that an outcome did or did not occur.
The study status is Terminated, but the reason is not reported in the registry record. That status does not on its own explain the study’s outcome, the reason for ending enrollment, or whether the study stopped because of safety, feasibility, administrative, or other considerations. The record reports enrollment of 15, while the safety summaries list 6 and 7 participants at risk; the relationship between those figures is not explained.
Overall, the posted information supports a cautious descriptive reading of a small safety experience. It does not support a claim of benefit or lack of benefit, nor a definitive comparison of the treatment regimens. Interpretation of efficacy, precision, and the complete safety profile would require analyses and details that are not reported in the registry record.
13. Why This Trial Matters Statistically
This trial is statistically instructive because its randomized design sits alongside a very small reported safety population and a primary endpoint that is not presented as one comparison. Randomization is valuable for comparative research, but it does not make descriptive counts precise or remove the need for an analysis that matches the registered endpoint. In a small study, the outcome of an individual participant can have substantial influence on the observed group summary.
The registry also illustrates why denominators and analysis populations matter. Total enrollment is 15, while the safety summaries report 6 participants at risk in the placebo group and 7 in the AC105 group. The record names the Safety Population but does not explain the relationship between these figures. A reader cannot assume that every enrolled participant contributed to every outcome or infer the reason for any difference in group counts.
A further statistical lesson is the distinction between adverse events occurring after treatment and events judged to be treatment-related. Timing and causation are different concepts. The endpoint description gives a timing definition for treatment-emergent events, but the record does not explain the relatedness-assessment process or provide a single treatment-related event comparison. The posted serious-event terms and counts therefore need to be read with attention to what each summary does—and does not—represent.
Finally, this record shows the limits of planning illustrations and descriptive results. A sample-size illustration based on an observed effect is not an original design justification and is not observed power. No statistical plan, interim-analysis information, or multiplicity procedure is reported. Distinguishing registered aims, posted outcome summaries, and unreported analytic details is essential to avoid making stronger claims than the record supports.
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 record reports a total enrollment of 15, while the safety summaries list 6 participants at risk in the placebo group and 7 in the AC105 group. It does not explain the relationship between enrollment and the safety denominators, whether all participants received the assigned regimen, or whether every participant contributed to each safety summary. This limits interpretation of the completeness and comparability of the safety counts.
The primary endpoint is described as a number of participants with treatment-related adverse events, but the record does not present a single primary-outcome comparison. It notes that the outcome has several categories or time points. The posted safety summaries do not include an uncertainty interval or formal statistical test, and the record does not explain how adverse-event relatedness was determined. It also defines treatment-emergent timing, which should not be mistaken for proof of causation.
The registry lists serious-event terms and percentages without an arm-specific breakdown in the record details. The denominator and event-counting rules for those percentages are not reported. The status is Terminated, but the reason is not reported in the registry record. These details constrain interpretation without explaining why the study ended.
Other important design and analysis details are not reported, including eligibility criteria beyond the stated condition, randomization implementation, the parties included in triple masking, the detailed Safety Population definition, missing-data handling, multiplicity procedures, and any interim analyses or statistical analysis plan. The record also does not provide a clinical activity estimate or numerical pharmacokinetic result. These limitations mean the posted information is best treated as a descriptive account rather than a complete comparative assessment.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: AC105 in Patients With Acute Traumatic Spinal Cord Injury — NCT01750684.
- Registry record last updated 2018-11-06; status last verified 2018-10.
- Results first posted 2016-06-13.
- 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
NCT01750684 is a phase 2 randomized, triple-masked, parallel-group, placebo-controlled study of AC105 in acute traumatic spinal cord injury, sponsored by Acorda Therapeutics. The study’s principal aim was to establish feasibility of rapid administration, safety, and tolerability. The active and placebo regimens each comprised an initial 30-minute intravenous infusion within a pre-specified post-injury window and 5 additional infusions at 6-hour intervals.
The record reports enrollment of 15, a study start of 2013-07, primary completion in 2015-02, and status Terminated. The primary endpoint concerns participants with treatment-related adverse events assessed using CTCAE v4.0. Safety summaries report serious events, other events, and deaths, but the record does not provide a single primary-outcome comparison or a formal analysis. The reason for termination and key analysis details are not reported in the registry record.