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 KAP for Depression in Abstinent Opioid Users (NCT05193318), a na phase 2 study. The primary outcome is Montgomery Asberg Depression Rating Scale.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT05193318 |
| Phase | Phase 2 |
| Condition | Opioid Use Disorder, Severe, in Sustained Remission, Opioid Use Disorder, Severe, in Early Remission, Major Depressive Disorder |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 5 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Medical University of South Carolina |
| Results posted | Yes |
2. Clinical Question
Population
Participants had severe opioid use disorder in sustained or early remission and major depressive disorder. The study focused on people with a history of opioid addiction who had not abused opioids for at least 3 months. The registry describes eligibility for participants with a Montgomery Asberg Depression Rating Scale (MADRS) score of 20 or higher. Enrollment was 5.
Intervention
Ketamine-assisted psychotherapy: 8 weekly intramuscular injections of ketamine hydrochloride, beginning at 0.5 mg/kg and increasing to a maximum of 1.5 mg/kg or a total dose of 60 mg, whichever was lower. Psychotherapy accompanied ketamine administration before, during and after each session.
Comparator
There was no comparator arm. The allocation was recorded as NA, masking was none, and the model was single group. Participants therefore were not assigned to a randomized control condition in this study.
Primary question
The primary outcome was change from baseline in MADRS score, measured across the listed follow-up weeks through week 16. The study was intended to examine ketamine-assisted psychotherapy in participants with persistent depression and opioid use disorder in remission. The registry record does not report the resulting MADRS changes or an analysis answering that question.
3. Trial Design
This was a phase 2, single-group study of ketamine-assisted psychotherapy for persistent depression in abstinent opioid users. The registry lists 5 enrolled participants. There was no randomized allocation, no like-for-like control arm and no masking. As a result, the design describes outcomes observed during a combined medication-and-psychotherapy program, not a controlled estimate of the effect of ketamine or psychotherapy separately.
The intervention was described as 8 weekly intramuscular injections of ketamine hydrochloride, starting at 0.5 mg/kg and increasing to a maximum of 1.5 mg/kg or a total dose of 60 mg, whichever was lower. Psychotherapy was scheduled before, during and after ketamine sessions. The registry summary says participation, including post-medication follow-up visits, would last about 16 weeks or 4 months.
The primary completion date is recorded as 2023-03-20, and the study status is terminated. The registry record does not report a termination date or a reason for termination. It also does not report a rationale for the enrollment target, a sample-size justification, or whether the planned intervention and follow-up were completed as described.
The primary measure was MADRS change from baseline at week 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, and 16. Secondary measures listed include the Beck Depression Inventory, Visual Analog Scale, Generalized Anxiety Disorder-7, Mystical Experience Questionnaire, Brief Pain Inventory, PTSD Checklist, and Timeline Follow-back. The registry lists 8 outcome measures, but does not report analyses for them.
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.
Acute Intervention (Weeks 1-9 of Study)
| Stage | Ketamine-assisted Psychotherapy |
|---|---|
| STARTED | 5 |
| COMPLETED | 4 |
| NOT COMPLETED | 1 |
Reasons for not completing this period:
| Reason | Ketamine-assisted Psychotherapy |
|---|---|
| Physician Decision | 1 |
Follow-up Phase (Through Week 16)
| Stage | Ketamine-assisted Psychotherapy |
|---|---|
| STARTED | 4 |
| COMPLETED | 3 |
| NOT COMPLETED | 1 |
Reasons for not completing this period:
| Reason | Ketamine-assisted Psychotherapy |
|---|---|
| Lost to Follow-up | 1 |
Analysis population for the primary outcome, as defined in the registry: Includes participants with available data. One participant dropped out after week 2, another failed to follow-up after week 9.
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 | Ketamine-assisted Psychotherapy |
|---|---|---|
| Participants analysed | 5 | |
| Age, Continuous | years | 31.2 (SD 8.1) |
| Sex: Female, Male: Female | Participants | 4 |
| Sex: Female, Male: Male | Participants | 1 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 |
| Race (NIH/OMB): Asian | Participants | 0 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 |
| Race (NIH/OMB): Black or African American | Participants | 0 |
| Race (NIH/OMB): White | Participants | 4 |
| Race (NIH/OMB): More than one race | Participants | 1 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| Sexual orientation: Heterosexual | Participants | 3 |
| Sexual orientation: Homosexual | Participants | 1 |
| Sexual orientation: Bisexual | Participants | 1 |
| MADRS baseline | units on a scale | 34.0 (SD 6.0) |
| BDI Baseline | units on a scale | 42.8 (SD 7.7) |
| GAD-7 Baseline | units on a scale | 18.4 (SD 1.8) |
6. Primary Endpoint
The registry lists the primary outcome as Montgomery Asberg Depression Rating Scale, measured over Change from baseline measured at week 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, and 16.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Deviation |
| Unit | score on a scale |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is change from baseline in the Montgomery Asberg Depression Rating Scale (MADRS), a clinician-administered questionnaire with 10 items assessing depression severity. Its total score ranges from 0-60; lower scores indicate less depression. The registry describes scores of 0-6 as normal, 7-19 as mild, 20-34 as moderate, and 35-60 as severe. A score of 20 or higher was specified for study inclusion.
The MADRS assesses clinical appearance of sadness, self-reported sadness, inner tension, reduced sleep, reduced appetite, concentration difficulties, lassitude, inability to feel, pessimistic thought process, and thoughts of suicide. It is used as a repeated measure of symptom severity, with change from baseline scheduled at week 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, and 16.
Change from baseline is intended to describe how scores vary over follow-up relative to each participant’s starting score. However, the registry record does not report the baseline or follow-up MADRS values, the mean changes, their standard deviations, or an analysis of the endpoint. The measure’s role and scheduled timing are reported, but the clinical pattern of results cannot be assessed from the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record describes the study question and planned measures, but it does not report the primary MADRS results. There is no posted mean change, standard deviation, confidence interval, test statistic or p-value for the primary endpoint. Therefore, the direction, size and precision of any observed change in depression scores are not reported in the registry record. The absence of an analysis in the record is not evidence that scores did or did not change.
The study enrolled 5 participants and used a single-group design. Without a control arm, changes over time could not be directly contrasted with changes under a comparator condition within this study. In general, a before-and-after pattern can describe what occurred among participants during follow-up, but it cannot by itself distinguish effects of the intervention from other influences, such as the passage of time, concurrent care, expectations, or natural variation. The registry does not report information that would quantify these possibilities.
Outcome availability is also limited. The primary outcome description says it includes participants with available data. It notes that one participant dropped out after week 2 and another failed to follow up after week 9. Consequently, the number of observations contributing at each scheduled time point may vary. The record does not give the observed number at each visit, explain how missing values were handled, or report whether the pattern of missingness was examined.
The study status is terminated, but the registry record does not state why. It does not report whether termination was related to recruitment, feasibility, safety, or another reason. Those possibilities should not be inferred from the status alone.
The safety record lists 0 serious adverse events affecting participants in the ketamine-assisted psychotherapy group and 0 deaths. It also lists 3 in the affected count for other adverse events, with 5 at risk for both serious and other adverse events. These figures are descriptive for this small group. They do not establish that an event cannot occur, and the record does not provide the specific other-event terms or detailed timing.
Overall, the posted record supports a description of the study design, eligibility, intervention, outcome schedule and limited safety counts. It does not support a quantitative estimate of change in MADRS or a controlled comparison. A treatment-effect conclusion would require outcome analyses and, for a comparative claim, an appropriate comparison design.
9. Statistical Methods Explained
Several statistical ideas help clarify what the registry record can and cannot establish. The points below distinguish general statistical explanation from methods explicitly described for this study.
What does a mean change describe?
The primary outcome is continuous: it is a score on a scale, and the listed parameter is the mean. In general, a mean summarizes the central tendency of a set of measurements. A mean change from baseline would summarize the average within-participant difference between a follow-up score and that participant’s baseline score, among the observations included in the analysis. A standard deviation describes how spread out individual scores or changes are around their mean. These summaries answer different questions: the mean describes the average, while the standard deviation describes variability.
The registry identifies the mean and standard deviation as the intended summary types, but does not report their observed values. The registry record also does not state whether the analysis used a separate mean at each visit, a repeated-measures model, or another method to account for measurements taken from the same participant over time. Repeated measurements from one person are generally correlated; a statistical method that treats them as independent would not reflect that dependence. Which approach was used is not reported in the registry record.
How should a confidence interval be read?
General explanation: a confidence interval expresses the uncertainty around an estimated quantity under a specified statistical procedure. A narrower interval indicates greater precision under that procedure, while a wider interval indicates less precision. An interval for mean change would help readers assess which values are compatible with the data and method, rather than relying only on a point estimate. No confidence interval for the primary outcome is reported in the registry record, so its precision cannot be evaluated.
A p-value, when reported, describes how compatible the observed data are with a specified null hypothesis under the assumptions of a test. It does not measure the size or importance of an effect. The registry lists 0 analyses, and it does not report a primary-outcome p-value or the statistical test used. No conclusion about statistical significance can therefore be drawn from the registered results.
What does the single-group design imply?
General explanation: a randomized comparison can help distinguish the effect of an assigned intervention from changes that might also occur without it, because groups are compared under a planned allocation process. This study was single group, with allocation recorded as NA and no masking. There is no randomized comparison in the registry record. Even if an outcome change had been reported, a within-group change would not alone identify the effect attributable to the combined intervention.
The intervention combines ketamine administration and psychotherapy. The registry does not describe separate intervention groups that could isolate the contribution of either component. Thus, the design is not suited to estimate the independent contribution of ketamine versus psychotherapy from a direct between-group contrast.
What do the planning assumptions mean?
The registry describes sample-size calculations as planning illustrations based on an observed effect, not as the trial’s own design. The stated assumptions are a two-sided significance level of 0.05, equal allocation between two arms, a normal approximation, and an effect to detect expressed as a stated fraction of the observed effect. The registry says that time-to-event calculations refer to the total number of events, while other calculations refer to participants per arm. The numerical planning estimates are not reported in the registry record.
These assumptions describe hypothetical planning for a two-arm comparison, not the actual single-group design. In general, a planning calculation estimates the sample size that would be needed under chosen assumptions; it does not measure the strength of evidence in a completed study. A sample-size illustration is not observed power. In particular, no effect estimate from the primary outcome is reported to assess as the basis for planning, and no sample-size justification for the enrolled group is reported.
When a planning calculation uses an observed effect, the estimate can be uncertain, especially when the underlying study has limited observations. General explanation: planning for a smaller fraction of an effect requires a larger sample than planning for a larger effect, all else equal. This is a general relationship, not a reported numeric result for this study. The registry does not report the assumed fractions or resulting sample-size values, so no specific planning requirement can be stated.
Why does missing follow-up matter?
General explanation: when follow-up measurements are missing, an analysis may describe only participants with observed values, or use a method intended to incorporate incomplete records. The interpretation depends on how missingness arose and how it was handled. The primary outcome description specifies participants with available data and records a dropout after week 2 and a failure to follow up after week 9. The method for handling these missing measurements is not reported in the registry record. With repeated outcomes scheduled through week 16, incomplete follow-up may also mean that the number of available measurements differs by time point.
Without visit-level counts and analysis details, readers cannot determine whether the reported data, if later posted, represent all enrolled participants at each time point or a changing subset. Nor can the registry record establish whether the missing data are related to participants’ symptom scores. Such details matter for interpreting both the estimated mean change and its uncertainty.
10. Multiplicity, Missing Data and Analysis Populations
The primary MADRS outcome is scheduled at multiple follow-up visits: week 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, and 16. The registry record does not identify which visit, if any, was designated as the main inferential time point, or describe a plan for interpreting results across these repeated measurements. It also does not report a multiplicity adjustment or explain whether the repeated visits were intended to be tested as a group. In general, when many outcomes or time points are examined, the chance of finding an apparently notable result by chance can increase; an analysis plan can specify how to address that issue. The registry record does not report such a plan.
The registry lists 8 outcome measures, including the primary MADRS measure and secondary measures of depression, anxiety, pain, PTSD symptoms, mystical experience and opioid use follow-up. It lists 0 analyses. The analysis population, statistical model, handling of repeated measures, and approach to multiple outcomes are not reported in the registry record. It is therefore not possible to determine which measures were analyzed or how results across measures were to be interpreted.
The primary outcome description says that participants with available data are included. It reports that one participant dropped out after week 2 and another failed to follow up after week 9. The registry record does not state whether the analysis was based on all enrolled participants, participants completing treatment, or participants with a specific minimum amount of follow-up. It also does not describe imputation, a missing-data model, sensitivity analyses, or reasons for the two incomplete follow-ups.
General explanation: an analysis limited to available observations can be biased if the likelihood of having a measurement depends on the unobserved outcome or related participant characteristics. Different assumptions about missing data can lead to different estimates. The number of observations at each visit and the reasons for missingness are important context, but they are not reported beyond the two follow-up descriptions. These omissions limit assessment of both the endpoint results and their precision.
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 |
|---|---|---|---|
| Ketamine-assisted Psychotherapy | 0 | 5 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Ketamine-assisted Psychotherapy | 0 of 5 |
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 |
|---|---|
| Ketamine-assisted Psychotherapy | 3 of 5 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Ketamine-assisted Psychotherapy |
|---|---|---|
| Nausea | Gastrointestinal disorders | 3 of 5 |
The registry lists 5 participants at risk for serious adverse events, 0 affected by serious adverse events, and 0 deaths in the ketamine-assisted psychotherapy group. For other adverse events, it lists 5 at risk and 3 in the affected count. The record provides no serious adverse-event terms and does not identify the specific other adverse-event terms.
These are descriptive counts for the enrolled group. In general, an affected count indicates how many participants were recorded as experiencing an event category, while an event count can refer to the number of occurrences; the registry’s displayed figures should be interpreted according to their labels. The available record does not give event timing, duration, severity details for other events, or whether events were considered related to the intervention.
Zero reported serious adverse events does not establish that serious events are impossible or that the intervention is safe in other populations. A small group provides limited information about uncommon events, and the record does not report a detailed safety analysis. The registry status is terminated, but it does not state whether safety was related to termination.
12. What the Result Does, and Does Not, Mean
The record establishes that a phase 2, single-group study of ketamine-assisted psychotherapy was registered for participants with major depressive disorder and opioid use disorder in remission. It describes the intervention schedule and identifies MADRS change from baseline as the primary outcome. It also reports limited adverse-event counts and notes incomplete follow-up for two participants.
It does not report the MADRS scores or changes, the mean and standard deviation, confidence intervals, p-values, or analyses of the listed outcomes. Accordingly, the record does not show the magnitude or precision of any symptom change. The missing analysis information should not be interpreted as evidence of benefit, lack of benefit, or no change.
Even if within-group outcome changes were available, the single-group design would not provide a randomized comparison with an untreated or alternative-treatment group. Change over time could not be separated from other possible influences by a direct comparison in this study. The combined treatment also means that the separate contribution of ketamine and psychotherapy is not identified by the design.
The safety counts are similarly limited: the registry reports no serious adverse events or deaths in the group, and records an affected count for other adverse events. These observations are not enough to characterize uncommon risks or establish safety beyond the participants and follow-up represented in the record.
The appropriate statistical reading is therefore narrow. The registry describes a planned clinical question and a small, uncontrolled study, but it does not report the outcome analyses needed to quantify results. It cannot establish a comparative treatment effect, and no clinical recommendation follows from the information in the record.
13. Why This Trial Matters Statistically
This trial matters statistically because it illustrates the difference between registering an outcome and reporting an analysis. MADRS change from baseline is clearly identified as the primary measure, with follow-up scheduled repeatedly through week 16. Yet the registry lists 0 analyses and no numerical primary results. Specifying an outcome makes the intended question visible; it does not supply evidence about the answer.
The design also highlights the distinction between observing change and estimating a treatment effect. A single-group study can describe trajectories among participants with available measurements, but it lacks a randomized comparator for separating intervention-associated change from other time-related influences. Because ketamine and psychotherapy are delivered together, the record also cannot distinguish their individual contributions through a direct contrast.
The limited enrollment and incomplete follow-up make transparent reporting especially important. The record notes a dropout after week 2 and a failure to follow up after week 9, but does not give visit-level availability or its missing-data approach. Without those details, readers cannot judge how the analyzed observations might represent participants over time or how precise an estimate would be.
Finally, the registry’s planning assumptions describe a hypothetical two-arm design, whereas the study itself is single group. This is a useful reminder that planning illustrations and an observed trial’s design answer different questions. Planning calculations depend on assumptions and do not substitute for reported outcome estimates or represent observed power.
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 most important limitation for interpreting results is that the registry does not report primary MADRS data or analyses. The mean changes, standard deviations, confidence intervals, p-values, and statistical methods are not reported in the registry record. The listed secondary outcomes also lack reported analyses.
The study enrolled 5 participants and had no randomized comparator or masking. It therefore cannot provide a controlled estimate of the effect of the combined intervention. Since ketamine administration was accompanied by psychotherapy, the contribution of either component separately is also not identifiable from the described design.
Follow-up was incomplete for at least two participants: one dropped out after week 2, and another failed to follow up after week 9. The record does not report the number of observations at individual visits, why these follow-ups were missed, or how missing measurements were handled. It also does not specify the analysis population or whether all scheduled visits were included in an analysis.
The status is terminated, but the registry does not report a reason or date for termination. It does not state whether the planned treatment and follow-up were completed as intended. The safety record gives only aggregate counts, without the specific terms for other adverse events, their timing, or their assessed relationship to the intervention.
These limitations mean that the record offers design and monitoring information but not an interpretable estimate of the primary outcome. They also preclude conclusions about comparative efficacy, the precision of outcome changes, or the broader safety profile.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: KAP for Depression in Abstinent Opioid Users — NCT05193318.
- Registry record last updated 2024-05-06; status last verified 2024-04.
- Results first posted 2024-05-06.
- 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
The registry record describes a phase 2, single-group study of ketamine-assisted psychotherapy for persistent depression in abstinent opioid users. It lists 5 enrolled participants and a terminated status. The intervention consisted of weekly intramuscular ketamine with psychotherapy, while the primary outcome was change from baseline in MADRS score through week 16.
The record lists 8 outcome measures and 0 analyses. It does not report primary-outcome values, statistical results, or the reason for termination. It notes one dropout after week 2 and one failure to follow up after week 9. The safety record lists 0 serious adverse events, 0 deaths, and 3 in the affected count for other adverse events. The design has no randomized comparator, so it cannot establish a controlled treatment effect.