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 Pharmacokinetic Study of DYANAVEL XR (Amphetamine) Extended-release Oral Suspension, in Children Aged 4 to 5 Years (NCT03610464), a na phase 4 study. The primary outcome is Plasma Concentrations of d- and L-amphetamine.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT03610464 |
| Phase | Phase 4 |
| Condition | Attention Deficit Hyperactivity 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 | Tris Pharma, Inc. |
| Results posted | Yes |
2. Clinical Question
The study asks what plasma concentration/time profile follows a single 2.5 mg dose of extended-release amphetamine oral suspension in children aged 4 to 5 years with attention-deficit/hyperactivity disorder. The primary outcome concerns measured concentrations of d- and l-amphetamine over the stated postdose period. The registry describes the study as a pharmacokinetic evaluation, rather than a comparison of treatment strategies.
Population
Children aged 4 to 5 years with attention-deficit/hyperactivity disorder. The listed primary-outcome population is the intention-to-treat population. Enrollment was 5.
Intervention
A single 2.5 mg dose of amphetamine extended-release oral suspension. The intervention is named Amphetamine Extended Release Suspension [Dyanavel]; the treatment description identifies a suspension containing 2.5 mg/mL amphetamine base.
Comparator
There is no comparator group. The registry identifies a single-group study, with no allocation to a control arm.
Primary question
What plasma concentration/time profile of d- and l-amphetamine is recorded from 0 to 28 hours postdose after the single dose?
That question is descriptive: it concerns how measured concentrations vary over time in the enrolled participants. It is not a question about a difference between randomized groups, because no like-for-like control comparison is identified. The registry record does not report concentration values, so the observed profile cannot be characterized from the recorded results. It also does not report comparative clinical outcomes or an estimate of treatment effect. The clinical question should therefore be read as a study objective, not as a conclusion about the concentrations actually observed.
3. Trial Design
The registry identifies NCT03610464 as a Phase 4, completed, single-group study. Its title describes a pharmacokinetic study of DYANAVEL XR extended-release oral suspension in children aged 4 to 5 years. The condition is attention-deficit/hyperactivity disorder, and the sponsor is Tris Pharma, Inc. The recorded start date is 2018-05-07 and the primary completion date is 2018-05-23.
Enrollment was 5. The study group is described as patients treated with amphetamine extended-release oral suspension, with the preparation identified as containing 2.5 mg/mL amphetamine base. The brief study description states that participants received a single 2.5 mg dose. The registry reports no allocation to different treatment groups and identifies no masking. It therefore does not describe a randomized or blinded comparison.
The primary outcome is plasma concentrations of d- and l-amphetamine, measured in ng/mL during 0-28 hours postdose. The stated measurement times are 0, 1, 3, 4, 6, 8, 10, 12, and 28 hours postdose. Concentrations are described using a geometric mean and standard deviation, and the outcome population is identified as the intention-to-treat population.
The record lists one outcome measure and zero analyses. The endpoint values and analysis results are not reported in the registry record. Details such as eligibility criteria beyond the age and condition description, participant flow, dosing procedures beyond the single-dose statement, and the statistical analysis plan are not reported in the registry record. The design description supports a narrow interpretation: this was a small, single-group study intended to characterize a concentration profile, not to estimate a between-group treatment effect.
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 | Study Patients (AMPH EROS) |
|---|---|
| STARTED | 5 |
| COMPLETED | 5 |
| NOT COMPLETED | 0 |
Analysis population for the primary outcome, as defined in the registry: intention to treat 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: Intention to treat
| Characteristic | Unit | Study Patients (AMPH EROS) |
|---|---|---|
| Participants analysed | 5 | |
| Age, Continuous | Years | 4 (SD 0) |
| Sex: Female, Male: Female | Participants | 2 |
| Sex: Female, Male: Male | Participants | 3 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 2 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 3 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| 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 | 3 |
| Race (NIH/OMB): White | Participants | 2 |
| Race (NIH/OMB): More than one race | Participants | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| Body Mass Index | kg/m^2 | 16.2 (SD 1.1) |
6. Primary Endpoint
The registry lists the primary outcome as Plasma Concentrations of d- and L-amphetamine, measured over 0-28 hours postdose.
| Element | Registry entry |
|---|---|
| Result type | Geometric Mean |
| Measure of spread | Standard Deviation |
| Unit | ng/mL |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is plasma concentration of d- and l-amphetamine, measured in ng/mL from 0 to 28 hours after dosing. The registry names measurement at 0, 1, 3, 4, 6, 8, 10, 12, and 28 hours postdose. The endpoint therefore describes drug concentrations at specified times rather than a clinical symptom score or a comparison between treatment groups. The registry identifies the intention-to-treat population for this outcome.
In general, pharmacokinetic measurements describe how concentration changes over time after a dose. A series of measurements can characterize the observed concentration/time profile within the period measured. The registry specifies a geometric mean as the summary parameter and standard deviation as the dispersion measure. In general, the geometric mean summarizes values on a multiplicative scale and can be useful when positive measurements vary proportionally; the standard deviation describes spread around the reported summary, subject to the scale and method used for calculation. The detailed calculation procedure is not reported in the registry record.
Concentration values at the scheduled times are not reported in the registry record. As a result, the actual profile, variability across participants, and precision of the endpoint estimate cannot be described. The endpoint definition indicates what was intended to be measured, but by itself it does not establish what concentrations were observed.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry describes a pharmacokinetic objective and names the outcome to be measured, but does not report the concentration results. It is therefore possible to describe the question and measurement schedule, but not the observed d- or l-amphetamine concentrations, their variation, or the shape of the concentration/time profile. The record identifies a geometric mean and standard deviation as the planned descriptive summaries; numerical summaries are not reported in the registry record.
The study enrolled 5 participants and used a single group. This means the record does not provide a contemporaneous control group for comparison. The question is consequently descriptive: what concentrations were observed after the specified dose in this group? It cannot, on the information reported, establish a contrast with another dose, formulation, population, or untreated group. The absence of a comparator is a design feature, not evidence that a comparison favored one treatment.
Precision is also not assessable from the recorded information. In general, a point estimate describes the value estimated from the observed data, while a confidence interval communicates uncertainty around that estimate under a specified statistical method. The registry record does not report concentration estimates or confidence intervals. It also does not report the participant-level measurements needed to evaluate how much the observations varied. The listed standard deviation would describe spread if numerical values were available, but no such values are reported.
The sample is small, with enrollment of 5, so any numerical summary would describe a limited set of observations. That does not by itself reveal how representative the participants were or how well the results might apply elsewhere; eligibility details and participant characteristics are not reported in the registry record. Nor can enrollment alone indicate whether the study met a target for statistical precision, because a sample-size justification is not reported in the registry record.
The registry lists one outcome measure and zero analyses. This is not equivalent to a reported null finding: no outcome values or analysis results are reported in the registry record. The status is completed, but completion status does not supply missing numerical results. A responsible reading distinguishes the study objective from the results actually recorded and avoids inferring an unreported concentration pattern, variability, or conclusion.
In general, statistical interpretation depends on both the estimand and the way data were collected and summarized. Here, the intended estimand is not fully specified beyond the concentration outcome, time window, summary parameter, dispersion measure, and named population. The detailed analysis procedure, handling of repeated measurements, missing observations, and any confidence interval method are not reported in the registry record. Without those details and the numerical outcomes, the registry supports a description of the study design, but not an assessment of the magnitude or precision of its pharmacokinetic findings.
9. Statistical Methods Explained
The primary outcome is a repeated concentration measurement over time in a single group. The record identifies plasma concentrations of d- and l-amphetamine in ng/mL, measured from 0 to 28 hours postdose. The scheduled time points are 0, 1, 3, 4, 6, 8, 10, 12, and 28 hours. It specifies a geometric mean with standard deviation as the summary, but the actual results and detailed calculation procedures are not reported in the registry record.
What does a concentration/time profile describe?
In general, a concentration/time profile tracks measured drug concentration at successive times after administration. Each measurement represents the concentration at a particular time, while the collection of measurements describes the pattern across the observation period. Measurements on the same participant are related rather than independent: they belong to one participant’s sequence. Statistical methods for repeated observations should account for that relationship when making estimates or inferences. The specific method used to account for repeated measurements is not reported in the registry record.
The recorded schedule defines when measurements were intended to be taken, not whether every scheduled value was obtained. Actual completion of measurements, deviations from scheduled times, and handling of missing or unusable samples are not reported in the registry record. A time point named in an outcome definition should therefore not be mistaken for a reported observation at that time.
Why report a geometric mean?
In general, the arithmetic mean summarizes values by adding them and dividing by the number of observations, while the geometric mean summarizes positive values on a multiplicative scale. The geometric mean can be useful when values are positive and their variation is better understood in proportional rather than additive terms. The registry specifies the geometric mean, but does not explain the reason for selecting it or state whether a log transformation was used in the analysis.
The standard deviation is named as the dispersion measure. In general, a standard deviation conveys how observations are spread around a summary on the scale on which it is calculated. Its interpretation depends on the scale and calculation method. If the geometric mean was calculated after transforming concentrations, the way the standard deviation was returned to the original scale would matter for interpretation; the calculation details are not reported in the registry record. No numerical geometric mean or standard deviation is reported, so the amount of observed variability cannot be evaluated.
What does uncertainty mean?
In general, a confidence interval gives a range of values compatible with the observed data under a specified model and procedure. Its width reflects both the variability in the data and the amount of information available, as well as the analysis method. It is not a guarantee that the true value lies inside the interval, nor does it describe the range of individual participant measurements. No confidence interval is reported in the registry record. Without an estimate and an uncertainty measure, neither the magnitude nor the precision of the endpoint can be assessed.
General statistical inference also depends on assumptions. Depending on the chosen method, relevant assumptions could concern the distribution of measurements, the relationship among repeated values, and the way missing observations arise. Which assumptions were used or checked is not reported in the registry record. These are general considerations, not claims about the analysis conducted in this study.
What can a single-group design estimate?
A single-group design can describe measurements collected from participants who received the study intervention. It does not create a randomized contrast with a separate control group. As a result, an observed concentration profile would describe the participants and conditions measured, rather than estimate a difference attributable to treatment relative to a comparator. No comparator is listed in the registry record.
The registry’s sample-size assumptions describe planning illustrations based on an observed effect, with a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. Those assumptions concern illustrations for a two-arm comparison and do not turn this single-group pharmacokinetic study into a controlled comparison. The observed effect used for such illustrations and the calculations themselves are not reported in the registry record. Any sample-size illustration is a planning aid, not observed power and not evidence about the concentration endpoint.
The registry lists an intention-to-treat population for the primary outcome. In general, intention-to-treat analysis refers to analyzing participants according to their assigned study group, regardless of adherence or treatment changes. In a single-group study without a control allocation, the operational details of that label require clarification from the protocol or analysis plan. Such details, including which participants contributed to each time point and how post-enrollment events were handled, are not reported in the registry record. The label alone does not establish that every enrolled participant had a usable value at every scheduled time.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists one outcome measure: plasma concentrations of d- and l-amphetamine over 0-28 hours postdose. It lists zero analyses. Although the outcome description includes two forms of amphetamine and multiple measurement times, the record does not specify how many hypothesis tests, contrasts, or derived summaries were planned. A statistical analysis plan, including any multiplicity procedure, is not reported in the registry record.
In general, multiplicity arises when several statistical claims are evaluated; without adjustment, repeated testing can increase the chance of at least one apparently notable result under a null model. This is a general concept, not a description of an analysis known to have occurred in this study. Because no inferential results or analysis details are reported, it is not possible to determine whether multiplicity was relevant to the analyses performed or how it was addressed.
The primary-outcome population is identified as the intention-to-treat population. Enrollment was 5, but the number contributing measurements at each time point and any analysis population counts are not reported in the registry record. Missing samples, missed visits, exclusions, and the handling of incomplete participant profiles are also not reported in the registry record. It is therefore not possible to assess whether all enrolled participants contributed to the endpoint or whether missing data could have affected the reported summaries.
In general, missing-data methods rely on assumptions about why values are missing and how the missingness relates to observed or unobserved measurements. A complete-case summary, imputation method, or model-based approach can have different implications. Which approach, if any, was used is not reported in the registry record. The absence of listed analyses should not be interpreted as evidence that there were no missing observations or that missingness had no effect.
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 |
|---|---|---|---|
| Study Patients (AMPH EROS) | 0 | 5 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Study Patients (AMPH EROS) | 0 of 5 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 3% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Study Patients (AMPH EROS) | 0 of 5 |
The registry’s safety figures list 5 participants at risk in the study group. It reports 0 participants affected by serious adverse events, 0 affected by other adverse events, and 0 deaths. No serious adverse event terms are listed. These are the counts recorded in the registry, not a complete account of every possible safety outcome.
In general, a count of participants affected is different from a count of event episodes: one participant can experience more than one event. The record reports participants affected, and does not provide event-level details or a fuller description of adverse-event collection. It also does not report the observation duration for safety beyond the study’s stated concentration measurement period. The figures therefore describe what was entered in these registry fields, rather than establishing that no events of any kind occurred.
The denominator is small, so the safety counts should be read as descriptive for this enrolled group. No rates, comparisons, or uncertainty estimates are reported in the registry record. The figures do not provide a controlled comparison, because the study has no comparator group. Missing details about event definitions, ascertainment, severity grading, and timing are not reported in the registry record. The safety counts should not be extended beyond the participants and information recorded.
12. What the Result Does, and Does Not, Mean
The record establishes that a completed Phase 4, single-group pharmacokinetic study enrolled 5 children aged 4 to 5 years with attention-deficit/hyperactivity disorder. Its stated objective was to evaluate plasma amphetamine concentrations after a single 2.5 mg dose of extended-release oral suspension. It defines the analytes, units, postdose window, scheduled measurement times, summary parameter, dispersion measure, and primary-outcome population.
Those details clarify what the study was designed to measure. They do not reveal the measured concentrations. The endpoint results, numerical summaries, and analysis results are not reported in the registry record. Accordingly, the registry record does not support a description of the observed concentration profile or the variability among participants. It also does not support an estimate of precision, because no confidence interval or other uncertainty measure is reported.
The record does not describe a control group or a randomized treatment comparison. Any measurements collected in this design would characterize the treated group; they would not by themselves provide a comparative estimate against a different formulation, dose, or control condition. The record also does not report clinical outcomes from which to infer a change in symptoms or other clinical effects. The study objective is pharmacokinetic, and interpretation should remain within that scope.
General statistical interpretation distinguishes evidence about what was measured from claims about what caused a difference or what would happen in a broader population. With no comparator and no numerical outcome results in the registry record, neither a comparative effect nor the direction and magnitude of the concentration findings can be stated. Information about participant characteristics beyond age and condition, adherence, missing measurements, and the analysis plan is also not reported in the registry record. These omissions limit assessment of generalizability and analytic choices.
The completion status and recorded enrollment are useful features of the study description, but they do not substitute for results. The most defensible conclusion is that the registry documents a small, single-group study with a specified concentration-measurement objective, while the numerical findings needed to evaluate that objective are not reported in the registry record. No conclusion about treatment benefit or lack of benefit follows from the information recorded.
13. Why This Trial Matters Statistically
This study is statistically useful to examine because its question and design are clearly descriptive, while its registry record illustrates the distinction between an endpoint definition and an endpoint result. The study specifies the analytes, unit, postdose window, measurement schedule, and descriptive summaries. Those features make the intended data structure understandable: repeated concentration measurements in a small, single group.
That structure raises familiar statistical considerations. In general, repeated measurements from the same participant are related, so the analysis method matters when summarizing or modeling change over time. The choice of a geometric mean also carries an interpretation tied to the scale of analysis. The registry does not state how repeated values were handled or why that summary was selected, and it does not report the numerical outcome. Readers can identify the methodological questions without pretending the answers are known.
The study also demonstrates why a sample count should not be confused with statistical power or precision. Enrollment was 5, but the registry does not report a sample-size justification or confidence intervals. The record’s planning assumptions describe illustrative two-arm calculations, whereas this study is single-group. Planning illustrations do not show observed power and do not replace an analysis of the data collected.
Finally, the record makes it important to distinguish completion from reporting. A completed study can have an outcome definition and safety entries without numerical endpoint results or analysis details in the registry record. For statistical readers, that distinction is central: conclusions require the actual estimates, information about uncertainty, and enough methods detail to understand how those estimates were obtained. This record documents the planned measurement objective, but not the evidence needed to evaluate its numerical findings.
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 interpreting the registry record is that concentration results are not reported. Although the primary outcome is defined in detail, no numerical d- or l-amphetamine measurements, geometric means, standard deviations, or confidence intervals are reported in the registry record. The observed time course and its precision therefore cannot be assessed.
Enrollment was 5, and the design is single-group with no comparator. This limits the scope of any potential inference to description of the enrolled participants and measured conditions. The record cannot support a between-group estimate, and the small enrollment offers limited information about variability across a broader population. Participant characteristics beyond age and condition are not reported in the registry record.
The registry names an intention-to-treat population, but does not report the number of participants contributing data at each time point, participant flow, missing measurements, or the handling of incomplete profiles. It does not specify the detailed statistical methods, calculation procedures, assumptions, confidence interval methods, or any multiplicity approach. These omissions make it difficult to evaluate how the planned summaries would have been calculated or how sensitive they might be to incomplete data or analytic choices.
The record also does not report a sample-size justification. Its stated planning assumptions concern illustrative two-arm calculations and do not establish a design rationale for this single-group study. Safety information is limited to the recorded counts of participants affected and deaths; event-level descriptions and additional ascertainment details are not reported in the registry record. These limitations are specific to the information documented and should not be filled by assuming unreported results or procedures.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Pharmacokinetic Study of DYANAVEL XR (Amphetamine) Extended-release Oral Suspension, in Children Aged 4 to 5 Years — NCT03610464.
- Registry record last updated 2019-06-25; status last verified 2019-06.
- Results first posted 2019-06-25.
- 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
NCT03610464 is a completed Phase 4, single-group pharmacokinetic study sponsored by Tris Pharma, Inc. It enrolled 5 children aged 4 to 5 years with attention-deficit/hyperactivity disorder. The study objective was to evaluate plasma amphetamine concentration over time after a single 2.5 mg dose of extended-release oral suspension.
The primary outcome was plasma concentrations of d- and l-amphetamine in ng/mL from 0 to 28 hours postdose, summarized using a geometric mean and standard deviation in the intention-to-treat population. Concentration values and analysis results are not reported in the registry record. The registry lists 0 participants affected by serious adverse events, 0 affected by other adverse events, and 0 deaths among 5 at risk.