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 Safety and Antiviral Activity of Entecavir in Participants With Chronic Hepatitis B Following Monotherapy in Other Entecavir Trials (NCT01438424), a na phase 2 study. The primary outcome is Overall Study: Number of Participants With Death As Outcome, Any Adverse Event (AE), Grade 3-4 AEs, Serious Adverse Events (SAEs), and Discontinuations Due to AEs.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01438424 |
| Phase | Phase 2 |
| Condition | Hepatitis B Virus, HBV |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 1053 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Bristol-Myers Squibb |
| Results posted | Yes |
2. Clinical Question
Population
Participants had chronic hepatitis B and had completed another entecavir trial without achieving virologic response or had relapsed during postdosing follow-up. The stated primary-outcome population includes all participants who received at least 1 dose of study drug in the current study. The registry enrollment is 1053, but the record does not report how many participants contributed data to each outcome.
Intervention
The study examined open-label entecavir. The arm description identifies entecavir, 1.0 mg, with or without lamivudine. The record also lists entecavir and lamivudine as interventions. Detailed treatment assignment, duration by participant, and the basis for using lamivudine are not reported in the registry record.
Comparator
No randomized comparator is identified: allocation is recorded as NA, masking as none, and the model as single group. Safety group labels in the posted results include multiple medicines, but the record cautions that these are not a like-for-like control comparison. They should not be interpreted as randomized study arms.
Primary question
The listed primary outcome counts participants with death, any adverse event, Grade 3-4 adverse events, serious adverse events, and discontinuations due to adverse events. It is assessed continuously from Day 1 through Week 240. The registry record does not report numerical results for these primary measures. Secondary outcomes include measures of HBV DNA, hepatitis B e antigen, and alanine transaminase, but their numerical results are not reported in the registry record.
3. Trial Design
This is a Phase 2, single-group, open-label study of entecavir in participants with chronic hepatitis B who had taken part in other entecavir trials. Its stated purpose was to provide entecavir to people who had not achieved virologic response in the earlier trial or who relapsed during postdosing follow-up. The study is titled as a preliminary assessment of safety and antiviral activity in this setting.
The registry records enrollment of 1053, a start date of 2001-01, primary completion of 2009-12, and completed status. These are registry-level study details; they do not establish how many participants were included in each outcome analysis. The analysis population specified for the primary outcome consists of all participants who received at least 1 dose of study drug in the current study.
Allocation is recorded as NA, masking as none, and the study model as single group. The listed intervention is open-label entecavir, with the arm description stating entecavir, 1.0 mg, with or without lamivudine. The record lists lamivudine as an intervention as well. It does not report detailed rules for treatment assignment, changes in treatment, or the duration of each participant’s exposure.
Safety monitoring for the primary outcome is described as continuous from Day 1 through Week 240. The record names secondary outcomes concerning sustained HBV DNA thresholds, HBV DNA categories and mean levels, loss of HBeAg, HBeAg seroconversion, mean ALT levels, and ALT normalization. Numerical results for these outcomes are not reported in the registry record. A statistical analysis plan, allocation procedure beyond the NA entry, and sample-size justification are not reported in the registry record.
The posted safety group labels include adefovir, several entecavir doses, lamivudine, missing, and placebo. These labels do not turn the study into a randomized comparison. The record explicitly cautions that the listed groups are not a like-for-like control comparison, so contrasts between their figures cannot establish comparative treatment effects.
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.
Before assignment: Of 1053 participants enrolled, 1051 received treatment.
Overall Study
| Stage | Entecavir, 0.5 or 1.0 mg, With or Without Lamivudine |
|---|---|
| STARTED | 1051 |
| COMPLETED | 634 |
| NOT COMPLETED | 417 |
Reasons for not completing this period:
| Reason | Entecavir, 0.5 or 1.0 mg, With or Without Lamivudine |
|---|---|
| Continuing treatment | 29 |
| Minimal virologic response | 95 |
| Not identified | 55 |
| Withdrawal by Subject | 104 |
| Progression of chronic hepatitis B | 22 |
| Death | 22 |
| Adverse Event | 17 |
| Lost to Follow-up | 17 |
| Abnormal laboratory test result | 14 |
| Need for drug prohibited by protocol | 14 |
| Pregnancy | 7 |
| No longer met inclusion criteria | 1 |
Analysis population for the primary outcome, as defined in the registry: All participants who received at least 1 dose of study drug in the current study.
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 | Entecavir, 0.5 or 1.0 mg, With or Without Lamivudine |
|---|---|---|
| Participants analysed | 1051 | |
| Age, Customized | Years | 41 (SD 13) |
| Sex: Female, Male: Female | Participants | 241 |
| Sex: Female, Male: Male | Participants | 810 |
| Race/Ethnicity, Customized: Asian/Pacific Islander | Participants | 544 |
| Race/Ethnicity, Customized: White | Participants | 481 |
| Race/Ethnicity, Customized: Black/African American | Participants | 18 |
| Race/Ethnicity, Customized: Missing | Participants | 2 |
| Race/Ethnicity, Customized: Native Hawaiian/Other Pacific Islander | Participants | 2 |
| Race/Ethnicity, Customized: Other | Participants | 2 |
| Race/Ethnicity, Customized: Filipino | Participants | 1 |
| Race/Ethnicity, Customized: Hispanic/Latino | Participants | 1 |
| Region: Continent: Asia | Participants | 451 |
| Region: Continent: Europe | Participants | 334 |
| Region: Continent: North America | Participants | 141 |
| Region: Continent: South America | Participants | 125 |
| Age | Years | 41 (17 to 78) |
6. Primary Endpoint
The registry lists the primary outcome as Overall Study: Number of Participants With Death As Outcome, Any Adverse Event (AE), Grade 3-4 AEs, Serious Adverse Events (SAEs), and Discontinuations Due to AEs, measured over Continuously from Day 1 through Week 240.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | Participants |
| Endpoint classification | Binary Endpoint |
The primary outcome is a set of participant counts: death as an outcome, any adverse event, Grade 3-4 adverse events, serious adverse events, and discontinuations due to adverse events. The stated assessment period is continuously from Day 1 through Week 240. The primary population is all participants who received at least 1 dose of study drug in the current study.
These measures are used to describe safety and tolerability during exposure. Counts of participants with any adverse event capture a broad range of unfavorable symptoms, signs, or diseases, including worsening of a pre-existing condition; the registry definition says an event may not be causally related to treatment. Grades describe severity, with Grade 3 defined as severe and Grade 4 as life-threatening or disabling. A serious adverse event is defined by specified consequences or circumstances, including death, life-threatening events, important medical events, and events requiring or prolonging hospitalization.
These categories are not interchangeable. Severity grade and seriousness describe different aspects of an event, while discontinuation due to an adverse event records a treatment consequence. The registry record names each measure but does not report the numerical primary-outcome results. Therefore, it does not permit a numerical description of the frequency of these outcomes across the stated primary population.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The study addresses safety and antiviral activity in a selected clinical context: participants had completed another entecavir trial without achieving virologic response or had relapsed during postdosing follow-up. That context matters when interpreting any response or safety findings. The results would describe this follow-on study population, not a general chronic hepatitis B population or a randomized comparison of treatment strategies.
The registry record identifies safety outcomes as primary and lists antiviral measures as secondary outcomes. Those secondary measures include sustained HBV DNA levels below <300 copies/mL and <10^4 copies/mL by PCR assay, HBV DNA categories and mean level, HBeAg loss and seroconversion, and mean ALT levels and ALT normalization. Numerical results for these measures are not reported in the registry record. The record also does not report numerical primary-outcome results in the primary outcome description. As a result, neither the magnitude nor the precision of the primary safety findings or antiviral findings can be assessed from those descriptions alone.
The posted safety data contain group-level counts for serious adverse events and other adverse events. For example, the entecavir, 0.5 mg, group is listed with 336 at risk for serious events and 57 affected; the same group is listed with 336 at risk for other events and 274 affected. These are descriptive counts attached to a registry group label. They should not be read as randomized estimates of relative safety: allocation is NA, the study model is single group, and the registry cautions that the groups are not like-for-like controls. The group labels also cover different medicines and doses, and the record does not explain their relationship to treatment histories or the study’s treatment assignment.
The serious-event terms listed most often include PNEUMONIA at 5.7%, with SJOGREN'S SYNDROME, INFLAMMATION, LYMPHOPROLIFERATIVE DISORDER, LYMPHOMA CUTIS, and VARICES OESOPHAGEAL each at 3.4%. The percentages describe the registry’s listed terms; the record does not provide enough detail to establish a causal relationship to entecavir or to interpret those percentages as comparative risks.
Some apparent precision is therefore unavailable. Confidence intervals, adjusted estimates, p-values, and outcome-specific analysis populations are not reported in the registry record. A count without an uncertainty interval can describe what was recorded but does not show how precise an underlying event rate estimate would be. The absence of reported statistical comparisons also means that no statistically supported between-group effect can be inferred.
The safest statistical reading is descriptive and limited: the record supplies some safety counts and serious-event terms, but does not provide the numerical primary endpoint results or the listed antiviral outcome results. It cannot establish treatment benefit, lack of benefit, or comparative safety.
9. Statistical Methods Explained
The registry describes a single-group, open-label study and records allocation as NA. That design description is central to the statistical interpretation. A randomized comparison is designed to support comparisons between assigned groups, subject to its assumptions and execution. The registry specifically cautions that the safety groups listed for this record are not a like-for-like control comparison. Differences among those group counts can reflect differences in who was included, treatment histories, dose labels, follow-up, or other factors; the record does not report enough detail to separate these possibilities.
What do participant counts describe?
A participant count is a direct summary of how many people in a defined group were recorded with an outcome. For a safety endpoint, such as participants with a serious adverse event, the count is meaningful only alongside its population definition and observation period. The primary outcome specifies participants who received at least 1 dose of study drug in the current study and monitoring continuously from Day 1 through Week 240. The posted results list at-risk and affected counts by safety group, but the relationship of those labeled groups to treatment assignment in this study is not fully reported.
Counts are not themselves rates, adjusted effects, or causal comparisons. A percentage may be useful as a descriptive summary, but its interpretation depends on the denominator and the way participants and events were handled. The registry lists selected serious-event terms with percentages, but does not describe a comparative model or adjusted analysis for those terms. No derived comparison should be treated as a treatment effect.
Why distinguish adverse-event categories?
The primary outcome separates any adverse event, Grade 3-4 adverse events, serious adverse events, and discontinuations due to adverse events. These categories answer different descriptive questions. An adverse event is defined as a new unfavorable symptom, sign, or disease, or worsening of a pre-existing condition; it may not be causally related to treatment. Grades classify severity. Seriousness is based on defined clinical consequences or circumstances, such as death, life-threatening events, important medical events, or hospitalization. Discontinuation records whether an adverse event led to stopping study treatment. A serious event is not automatically a Grade 3-4 event, and a severe event is not necessarily a serious event under the stated definitions.
The registry includes continuous safety assessment from Day 1 through Week 240. Continuous monitoring describes the specified observation window; it does not establish that every participant was followed for the entire period. Individual follow-up, exposure duration, censoring, and missing safety observations are not reported in the registry record.
What can be concluded from the listed analyses?
The registry records 26 outcome measures and zero analyses. That distinction matters: named outcomes identify what was intended to be measured, while an analysis provides a numerical result and its statistical context. The eight named secondary outcomes cover HBV DNA, HBeAg, and ALT measures, but numerical results for them are not reported in the registry record. Likewise, the primary outcome description specifies safety measures without giving their numerical results there.
No statistical model, confidence intervals, p-values, covariate adjustment, or formal comparison procedure is reported in the registry record. A confidence interval, in general, expresses uncertainty around an estimate under the assumptions of the method used; without an estimate and its interval, precision cannot be evaluated. A p-value, in general, measures how incompatible the data are with a specified statistical model or null hypothesis, but no such values or tested hypotheses are reported. These general concepts do not imply that those analyses were conducted.
How should the planning illustrations be read?
The sample-size illustrations are explicitly described as planning illustrations computed from an observed effect, not as the trial’s own design. Their stated assumptions are a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation; the effect to detect is a stated fraction of the observed effect. For time-to-event calculations, the illustration gives a total number of events using the Schoenfeld method; other calculations are expressed as participants per arm for the stated power target.
Such illustrations are hypothetical planning quantities, not observed trial results and not observed power. They do not establish that the study planned to recruit those quantities, followed the illustrated allocation, or used those methods in its actual analysis. The trial is registered as a single-group study, and allocation is NA, so the equal-allocation assumption in a two-arm illustration should not be mistaken for the recorded study design. The statistical plan and sample-size justification are not reported in the registry record.
Over-dispersion is a general concern when outcome variability is greater than a model expects; if ignored, uncertainty estimates can be too narrow. The registry does not report a model for over-dispersed outcomes or indicate that this issue arose in the analysis. This is a general methodological point, not a finding about this study.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists 26 outcome measures, including secondary outcomes addressing sustained HBV DNA thresholds, HBV DNA categories and mean level, HBeAg loss and seroconversion, and ALT levels and normalization. When multiple outcomes are assessed, the chance of at least one apparently notable result can increase if each is tested separately without a prespecified strategy. General approaches to multiplicity may prioritize outcomes, adjust testing thresholds, or distinguish confirmatory from exploratory analyses. The registry record does not report a multiplicity strategy, outcome hierarchy, or statistical analysis plan.
The record lists zero analyses. Numerical results for the named secondary outcomes are not reported in the registry record, and numerical primary outcome results are not given in the primary outcome description. Consequently, there are no reported outcome-level estimates or test results on which to assess the conduct or consequences of multiplicity adjustment.
The primary outcome population is all participants who received at least 1 dose of study drug in the current study. The registry does not report the participant counts analyzed for each outcome, how missing measurements were handled, whether participants with incomplete follow-up were excluded or retained, or how discontinuation affected endpoint assessment. Missing-data methods, imputation, and sensitivity analyses are not reported in the registry record.
These omissions limit interpretation because the analysis population and missing-data approach determine which participants contribute to an estimate and what assumptions are needed to interpret it. They also make it impossible to evaluate whether the listed outcomes were analyzed consistently. No particular missing-data or multiplicity procedure should be assumed.
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 |
|---|---|---|---|
| Adefovir, 10 mg | 7 | 35 | 20.0% |
| Entecavir, 0.02588 mg | 0 | 1 | 0.0% |
| Entecavir, 0.1 mg | 3 | 29 | 10.3% |
| Entecavir, 0.5 mg | 57 | 336 | 17.0% |
| Entecavir, 1.0 mg | 15 | 123 | 12.2% |
| Lamovidine, 100 mg | 87 | 523 | 16.6% |
| Missing | 0 | 2 | 0.0% |
| Placebo | 0 | 2 | 0.0% |
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 |
|---|---|
| Adefovir, 10 mg | 27 of 35 |
| Entecavir, 0.02588 mg | 0 of 1 |
| Entecavir, 0.1 mg | 25 of 29 |
| Entecavir, 0.5 mg | 274 of 336 |
| Entecavir, 1.0 mg | 94 of 123 |
| Lamovidine, 100 mg | 439 of 523 |
Most frequent serious adverse event terms
| Event term | Organ system | Adefovir, 10 mg | Entecavir, 0.02588 mg | Entecavir, 0.1 mg | Entecavir, 0.5 mg | Entecavir, 1.0 mg | Lamovidine, 100 mg |
|---|---|---|---|---|---|---|---|
| ALANINE AMINOTRANSFERASE INCREASED | Investigations | 0 of 35 | 0 of 1 | 0 of 29 | 6 of 336 | 3 of 123 | 16 of 523 |
| HEPATIC NEOPLASM MALIGNANT | Neoplasms benign, malignant and unspecified (incl cysts and polyps) | 1 of 35 | 0 of 1 | 0 of 29 | 4 of 336 | 0 of 123 | 8 of 523 |
| ASPARTATE AMINOTRANSFERASE INCREASED | Investigations | 0 of 35 | 0 of 1 | 0 of 29 | 0 of 336 | 0 of 123 | 6 of 523 |
| CELLULITIS | Infections and infestations | 1 of 35 | 0 of 1 | 0 of 29 | 2 of 336 | 0 of 123 | 1 of 523 |
| APPENDICITIS | Infections and infestations | 0 of 35 | 0 of 1 | 0 of 29 | 1 of 336 | 0 of 123 | 3 of 523 |
| OVERDOSE | Injury, poisoning and procedural complications | 0 of 35 | 0 of 1 | 0 of 29 | 2 of 336 | 1 of 123 | 1 of 523 |
| INGUINAL HERNIA | Gastrointestinal disorders | 0 of 35 | 0 of 1 | 0 of 29 | 2 of 336 | 0 of 123 | 1 of 523 |
| CHOLELITHIASIS | Hepatobiliary disorders | 0 of 35 | 0 of 1 | 0 of 29 | 1 of 336 | 0 of 123 | 2 of 523 |
| ABDOMINAL PAIN UPPER | Gastrointestinal disorders | 0 of 35 | 0 of 1 | 0 of 29 | 1 of 336 | 0 of 123 | 2 of 523 |
| GASTROENTERITIS | Infections and infestations | 1 of 35 | 0 of 1 | 0 of 29 | 0 of 336 | 1 of 123 | 1 of 523 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Adefovir, 10 mg | Entecavir, 0.02588 mg | Entecavir, 0.1 mg | Entecavir, 0.5 mg | Entecavir, 1.0 mg | Lamovidine, 100 mg |
|---|---|---|---|---|---|---|---|
| UPPER RESPIRATORY TRACT INFECTION | Infections and infestations | 9 of 35 | 0 of 1 | 5 of 29 | 89 of 336 | 27 of 123 | 154 of 523 |
| HEADACHE | Nervous system disorders | 3 of 35 | 0 of 1 | 13 of 29 | 69 of 336 | 16 of 123 | 131 of 523 |
| NASOPHARYNGITIS | Infections and infestations | 8 of 35 | 0 of 1 | 5 of 29 | 60 of 336 | 18 of 123 | 83 of 523 |
| COUGH | Respiratory, thoracic and mediastinal disorders | 5 of 35 | 0 of 1 | 4 of 29 | 48 of 336 | 15 of 123 | 77 of 523 |
| BACK PAIN | Musculoskeletal and connective tissue disorders | 1 of 35 | 0 of 1 | 5 of 29 | 46 of 336 | 12 of 123 | 84 of 523 |
| ALANINE AMINOTRANSFERASE INCREASED | Investigations | 1 of 35 | 0 of 1 | 6 of 29 | 33 of 336 | 11 of 123 | 86 of 523 |
| DIARRHOEA | Gastrointestinal disorders | 5 of 35 | 0 of 1 | 1 of 29 | 44 of 336 | 12 of 123 | 69 of 523 |
| HYPERTENSION | Vascular disorders | 1 of 35 | 0 of 1 | 4 of 29 | 44 of 336 | 13 of 123 | 63 of 523 |
| ABDOMINAL PAIN UPPER | Gastrointestinal disorders | 1 of 35 | 0 of 1 | 7 of 29 | 42 of 336 | 7 of 123 | 67 of 523 |
| FATIGUE | General disorders | 2 of 35 | 0 of 1 | 7 of 29 | 36 of 336 | 13 of 123 | 63 of 523 |
Serious events with the highest arm-level rate: pneumonia (5.7%), sjogren's syndrome (3.4%), inflammation (3.4%), lymphoproliferative disorder (3.4%), lymphoma cutis (3.4%).
The posted safety data give, for each listed group, counts at risk and counts affected for serious events and other events. For example, the entecavir, 1.0 mg, label is accompanied by 123 at risk and 15 affected for serious events, and 123 at risk and 94 affected for other events. These are descriptive registry counts, not adjusted estimates. Death counts are not reported in the registry record.
Group labels include Adefovir, 10 mg; several entecavir doses; Lamovidine, 100 mg; Missing; and Placebo. Their presence should not be read as evidence that participants were randomized among these treatments in this study. Allocation is NA, the model is single group, and the registry expressly warns that the groups are not like-for-like controls. The record does not explain in detail how these labels relate to the current study’s treatment history or safety population.
The listed serious-event terms include PNEUMONIA (5.7%), SJOGREN'S SYNDROME (3.4%), INFLAMMATION (3.4%), LYMPHOPROLIFERATIVE DISORDER (3.4%), LYMPHOMA CUTIS (3.4%), and VARICES OESOPHAGEAL (3.4%). These term percentages are descriptive entries. They do not establish that the events were caused by entecavir. The registry definition also allows adverse events that may not be causally related to treatment, and comparative estimates and uncertainty intervals are not reported.
12. What the Result Does, and Does Not, Mean
The record documents a follow-on study intended to provide open-label entecavir to participants with chronic hepatitis B after another entecavir trial, in the setting of no virologic response or relapse during postdosing follow-up. It identifies safety outcomes for continuous monitoring from Day 1 through Week 240 and lists antiviral outcomes involving HBV DNA, HBeAg, and ALT.
What the record does not establish is equally important. Numerical results for the named primary safety measures are not reported in the primary outcome description, and numerical results for the listed antiviral outcomes are not reported in the registry record. The safety entries do provide group-level at-risk and affected counts and selected serious-event terms, but the registry warns that the groups are not a like-for-like control comparison. These data should therefore be read as descriptive entries, not as estimates of comparative benefit or harm.
A record of an adverse event does not by itself establish that the study drug caused it. The registry definition explicitly allows an event that may not be causally related to treatment. In addition, serious events and severe events are defined differently, and the posted counts do not provide a complete account of the relationship between those categories for individual participants.
Statistical precision cannot be judged without outcome-specific estimates and their uncertainty measures. The registry record does not report confidence intervals, comparative tests, adjusted estimates, or outcome-specific analysis populations. The listed enrollment of 1053 does not substitute for those details and should not be assumed to be the denominator for every outcome.
Accordingly, the record supports a description of the study’s intent, design, outcome definitions, and selected safety data. It does not, by itself, show whether entecavir achieved antiviral response, establish a causal safety profile, or support comparisons among the listed group labels. No treatment recommendation follows from these registry entries.
13. Why This Trial Matters Statistically
This trial matters statistically because it illustrates the distinction between a study’s stated aims, its outcome definitions, and the numerical results available for interpretation. The record describes a clinically specific follow-on population and names both safety and antiviral outcomes. However, the numerical primary safety results and the numerical results for the listed antiviral outcomes are not reported in the registry record. An outcome list is not a substitute for estimates, denominators, and uncertainty.
It also highlights why study design governs what comparisons can mean. The record identifies a single-group model, no masking, and allocation as NA. Safety figures are listed under multiple treatment labels, but the registry cautions that they are not like-for-like controls. Treating those labels as randomized arms would overstate what the design supports. Descriptive group counts can be useful for documenting observed events, but they do not isolate the effect of treatment from differences in the groups.
The record further distinguishes event count from causal attribution. The adverse-event definition allows events that may not be related to treatment, while seriousness and severity use separate criteria. Reading those categories correctly prevents a count of recorded events from being mistaken for a count of confirmed drug-caused harms.
Finally, the registry lists 26 outcome measures and zero analyses. The absence of reported analyses means that readers cannot assess statistical uncertainty, multiplicity handling, or outcome-specific missingness from the record. This is a useful reminder that transparency about populations, analytic methods, and numerical estimates is needed for a full statistical appraisal. The registry entries can describe the study framework and selected safety observations, but they do not provide a complete inferential account of the study.
14. Limitations
- The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
- Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.
The registry record does not report the numerical results for the primary safety outcomes in the primary outcome description or numerical results for the named antiviral outcomes. This prevents assessment of the size and precision of the intended safety and antiviral findings. It also records zero analyses, so estimates, uncertainty intervals, and inferential test results are unavailable in the registry record.
The study is described as single group, with allocation recorded as NA and masking as none. The safety data nevertheless contain group labels for multiple medicines and doses. The registry cautions that these groups are not a like-for-like control comparison, and does not report enough detail to establish how each group relates to participants’ treatment history or current study exposure. Comparisons among these figures would therefore be vulnerable to differences in group composition and follow-up.
The record reports enrollment of 1053 but does not provide outcome-specific denominators or analysis populations beyond the primary population definition. It does not report the handling of missing data, participant-level follow-up, exposure duration, or discontinuations in relation to outcome assessment. The stated continuous observation window from Day 1 through Week 240 does not by itself show that every participant was observed for the full period.
Statistical methods, a multiplicity strategy, a sample-size justification, and an analysis plan are not reported in the registry record. Death counts are not reported in the posted safety data. The listed serious-event terms and percentages are descriptive and do not establish causation. These limitations leave the registry useful for identifying the study’s purpose and recorded outcome framework, but insufficient for a full assessment of efficacy, comparative safety, or statistical precision.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Safety and Antiviral Activity of Entecavir in Participants With Chronic Hepatitis B Following Monotherapy in Other Entecavir Trials — NCT01438424.
- Registry record last updated 2012-08-23; status last verified 2012-07.
- Results first posted 2012-08-23.
- Data retrieved from ClinicalTrials.gov on 2026-11-09.
- Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.
Continue through the Clinical Biostats statistical pathway
Use this trial's endpoint as a starting point for deeper study of effect measures, confidence intervals, and sample-size planning.
18. Record Summary
NCT01438424 is a completed Phase 2, open-label, single-group study of entecavir in participants with chronic hepatitis B after another entecavir trial. Its stated purpose was to provide entecavir to participants who had not achieved virologic response or had relapsed during postdosing follow-up. Registry enrollment is 1053; the recorded start is 2001-01 and primary completion is 2009-12.
The primary outcome lists counts for death, any adverse event, Grade 3-4 adverse events, serious adverse events, and discontinuations due to adverse events, with monitoring from Day 1 through Week 240. Secondary outcomes concern HBV DNA, HBeAg, and ALT. The record lists selected safety counts and serious-event terms, but numerical primary outcome results and numerical secondary outcome results are not reported in the registry record. Allocation is NA, and the registry cautions that the listed safety groups are not like-for-like controls.