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 Peg-interferon ADDed to an Ongoing Nucleos(t)Ide Based Treatment in Patients With Chronic Hepatitis B to Induce Decrease of HBs-Antigen (NCT01524679), a randomized phase 2 study. The primary outcome is Difference in Percentage of Patients Between Treatment and Comparator Arm Reaching a ≥ 1log10 Decline of Quantitative HBsAg After 48 Weeks.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01524679 |
| Phase | Phase 2 |
| Condition | Chronic Hepatitis B |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 170 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Johannes Gutenberg University Mainz |
| Results posted | Yes |
2. Clinical Question
Population
The trial enrolled people with chronic hepatitis B who were HBe antigen negative, already receiving an oral antiviral regimen, and had a nondetectable viral load for at least 12 months. The primary-outcome population was defined as all randomized participants with at least one post-baseline measurement. The number meeting that analysis-population definition is not reported in the registry record.
Intervention
The treatment strategy was pegylated interferon alfa-2a, identified as Pegasys®, at 180 μg once weekly for 48 weeks, added to ongoing nucleos(t)ide-based treatment.
Comparator
The control strategy was ongoing nucleos(t)ide-based treatment alone. The registry record does not give further detail about the particular background antiviral regimens used.
Primary question
The trial asked whether adding pegylated interferon alfa-2a increased the percentage of participants reaching at least a 1log10 decline in quantitative HBsAg after 48 weeks, compared with ongoing nucleos(t)ide treatment alone. The registry record does not report the percentages by arm or a numerical between-arm estimate, so the magnitude and precision of the primary comparison cannot be assessed from that record.
3. Trial Design
This was a prospective, randomized, open-label, parallel-group phase IIb clinical trial. The registry record lists enrollment of 170 participants and a completed status. Treatment was assigned to one of two strategies: pegylated interferon alfa-2a added to ongoing nucleos(t)ide-based treatment, or ongoing nucleos(t)ide-based treatment alone. Masking was listed as none, so the study was open-label.
The intended study population was specific: participants had chronic HBeAg-negative hepatitis B, were already receiving oral antiviral treatment, and had a nondetectable viral load for at least 12 months. The record does not describe which nucleos(t)ide regimens participants received, how long they had been on them, or how treatment assignment was generated or concealed. Those details are not reported in the registry record.
The primary outcome was assessed after 48 weeks and concerned the percentage reaching a threshold decline in quantitative HBsAg. Secondary outcomes listed changes in quantitative HBs antigen at week 12 and week 24. The registry record does not give numerical results for those secondary outcomes. It also does not report a protocol-level explanation for the chosen follow-up schedule or a sample-size justification.
Randomization can help balance both measured and unmeasured participant characteristics across treatment groups, on average. Open-label assignment can still matter when outcomes or treatment decisions involve judgment. The primary endpoint is based on a laboratory measurement, but the record does not describe laboratory blinding or other procedures intended to limit awareness of allocation. No conclusion about the effects of these design features on the reported analyses can be made from the registry record alone.
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 | Treatment Group | Control Group |
|---|---|---|
| STARTED | 112 | 58 |
| COMPLETED | 89 | 49 |
| NOT COMPLETED | 23 | 9 |
Reasons for not completing this period:
| Reason | Treatment Group | Control Group |
|---|---|---|
| Lost to Follow-up | 1 | 4 |
| Withdrawal by Subject | 4 | 4 |
| Adverse Event | 9 | 0 |
| Protocol Violation | 1 | 0 |
| Lack of Efficacy | 2 | 0 |
| e.g.wish for children, relocation | 6 | 1 |
Analysis population for the primary outcome, as defined in the registry: mITT population consisting of all randomized patients with at least one post-baseline measurement
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: The Baseline Analysis Population is the modified ITT population consisting of all randomized patients with at least one available post-baseline assessment.
| Characteristic | Unit | Treatment Group | Control Group | Total |
|---|---|---|---|---|
| Participants analysed | 110 | 55 | 165 | |
| Age, Continuous | years | 43.8 (SD 9.6) | 45.1 (SD 9.7) | 44.3 (SD 9.6) |
| Sex: Female, Male: Female | Participants | 26 | 16 | 42 |
| Sex: Female, Male: Male | Participants | 84 | 39 | 123 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Asian | Participants | 15 | 6 | 21 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Black or African American | Participants | 7 | 6 | 13 |
| Race (NIH/OMB): White | Participants | 85 | 39 | 124 |
| Race (NIH/OMB): More than one race | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 3 | 4 | 7 |
| Region of Enrollment: Germany | participants | 110 | 55 | 165 |
| Virology: HBV DNA quant. negative?: Yes | Participants | 109 | 54 | 163 |
| Virology: HBV DNA quant. negative?: No | Participants | 1 | 1 | 2 |
| Virology: Anti-HBs: Positive | Participants | 7 | 2 | 9 |
| Virology: Anti-HBs: Negative | Participants | 103 | 53 | 156 |
| Virology: HBeAg: Positive | Participants | 0 | 0 | 0 |
| Virology: HBeAg: Negative | Participants | 110 | 55 | 165 |
| Virology: Anti-HBe: Positive | Participants | 96 | 45 | 141 |
| Virology: Anti-HBe: Negative | Participants | 11 | 10 | 21 |
| Virology: Anti-HBc: Positive | Participants | 94 | 48 | 142 |
| Virology: Anti-HBc: Negative | Participants | 15 | 7 | 22 |
| Virology: HCV: Positive | Participants | 0 | 0 | 0 |
| Virology: HCV: Negative | Participants | 110 | 55 | 165 |
| Virology: HDV: Positive | Participants | 0 | 0 | 0 |
| Virology: HDV: Negative | Participants | 110 | 55 | 165 |
| Virology: HIV: Positive | Participants | 0 | 0 | 0 |
| Virology: HIV: Negative | Participants | 109 | 55 | 164 |
| HBV Genotype known?: Yes | Participants | 22 | 12 | 34 |
| HBV Genotype known?: No | Participants | 88 | 43 | 131 |
| HBV Genotype: Genotype A | Participants | 2 | 1 | 3 |
| HBV Genotype: Genotype C | Participants | 1 | 0 | 1 |
| HBV Genotype: Genotype D | Participants | 16 | 11 | 27 |
| HBV Genotype: Genotype E | Participants | 1 | 0 | 1 |
| HBV Genotype: Wildtype | Participants | 1 | 0 | 1 |
| HBV Genotype: Not specified | Participants | 1 | 0 | 1 |
6. Primary Endpoint
The registry lists the primary outcome as Difference in Percentage of Patients Between Treatment and Comparator Arm Reaching a ≥ 1log10 Decline of Quantitative HBsAg After 48 Weeks, measured over 48 weeks.
| Element | Registry entry |
|---|---|
| Result type | Count Of Participants |
| Measure of spread | not applicable |
| Unit | Participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint concerns whether a participant had at least a 1log10 decline in quantitative HBsAg after 48 weeks. The endpoint description calls this a tenfold reduction. It is a binary outcome at the participant level: each person either reached the specified decline threshold or did not. The planned comparison is the difference between treatment groups in the percentage of participants reaching that threshold.
A threshold outcome can make a clinical trial question easier to state: it focuses attention on the proportion of participants meeting a defined response criterion, rather than on the full spread of changes in HBsAg values. That convenience comes with a limitation. Participants just on opposite sides of the threshold are treated as different outcome categories, while participants with substantially different declines may be placed in the same category. This is a general property of dichotomizing a continuous measurement.
The registry record does not report the number or percentage reaching the threshold in either group, the between-group difference, or its confidence interval. It therefore does not establish how often the threshold was reached or how precisely the groups differed. The record also does not explain whether the threshold was selected for clinical reasons, prior evidence, or another rationale; that rationale is not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies the primary efficacy question but does not provide a single numerical result for it. It describes a between-group comparison of the percentage reaching at least a 1log10 decline in quantitative HBsAg after 48 weeks. However, the record indicates that the primary outcome has several categories or time points and is not reduced to one comparison. No arm-specific response counts or percentages, effect estimate, confidence interval, or p-value are reported in a form that supports a single primary comparison.
This means the direction, magnitude, and precision of the primary result cannot be determined from the registry record. A percentage difference would describe how far apart the groups were on the chosen threshold outcome. A confidence interval would communicate the range of effect sizes compatible with the data and analysis, subject to the method’s assumptions. Without those quantities, it is not possible to distinguish a small estimate from a large one, or a precise estimate from one with substantial uncertainty.
The secondary outcomes listed are changes in quantitative HBs antigen at week 12 and week 24. Numerical estimates and uncertainty for those outcomes are not reported in the registry record. The record also does not provide a statistical analysis plan, so it is not possible to determine which model or test was used for the primary outcome, how the multiple listed outcome measures were handled, or whether adjusted and unadjusted analyses were planned.
The trial is marked completed, and enrollment is listed as 170. Completion status does not itself supply an efficacy estimate, nor does enrollment show how many participants contributed to the primary analysis. The analysis population was defined as all randomized participants with at least one post-baseline measurement, but the number in that population is not reported in the registry record.
The safety counts are separate from the efficacy question. The registry record lists serious adverse events and other adverse events by group, as well as zero deaths in each group. These descriptive counts do not fill in the missing primary endpoint results, and they should not be interpreted as a formal comparison of overall safety without further information about event definitions, follow-up, and analysis.
Accordingly, the posted registry information supports an account of the trial question, design, endpoint definition, and selected safety counts. It does not support a quantitative conclusion about the primary efficacy comparison. This is a limitation of what is reported in the registry record, not evidence that an effect was absent or present.
9. Statistical Methods Explained
The registry record identifies a binary primary outcome and a comparison of percentages between randomized groups, but it does not report the statistical method used for that comparison. The explanations below describe general statistical concepts relevant to such an endpoint; they should not be read as a description of the trial’s actual analysis unless the registry record states it.
What does the binary outcome represent?
For each participant, the primary endpoint classifies whether the HBsAg decline reached the specified threshold by 48 weeks. A group percentage would be the proportion of participants in that group who met the criterion. Comparing the two proportions summarizes the contrast in the frequency of this defined response. Because the endpoint is threshold-based, it does not retain all the information in the underlying quantitative HBsAg measurements. Analyses of the continuous measurements and analyses of the threshold outcome answer related but different questions.
What would a difference in percentages mean?
A difference in percentages expresses the gap between the groups on the same response definition. Its interpretation depends on which group has the higher response percentage and on the size of the estimate. The registry record does not report those percentages or the estimated difference, so neither direction nor magnitude can be described. The planned comparison is stated in the endpoint description, but the result needed to interpret that comparison is not reported in the registry record.
How should uncertainty be understood?
In general, a confidence interval gives a range of values that are reasonably compatible with the observed data under the statistical method and its assumptions. A narrow interval indicates greater precision than a wide interval, while an interval spanning values on different sides of no difference may leave the direction of the effect uncertain. A p-value, when reported, assesses compatibility between the data and a specified null hypothesis under a chosen model; it does not measure the size or clinical importance of an effect. Neither a confidence interval nor a p-value for the primary efficacy comparison is reported in the registry record.
For a binary endpoint, precision depends in part on the numbers of participants and outcome events contributing to each group, as well as the analysis method. Enrollment alone does not establish the size of the analyzed population. Here, the primary population is defined as all randomized participants with at least one post-baseline measurement, but its size and the response counts are not reported in the registry record. No recalculated efficacy estimate can therefore be described.
What can the planning illustrations tell readers?
Planning illustrations use assumptions to show how a hypothetical study might be sized to detect an effect. The assumptions described for the illustrations include 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. These are planning assumptions, not evidence about how the trial was designed. The registry record does not report the trial’s own sample-size justification. Because no observed primary effect is available as a single comparison, the illustrations cannot be interpreted as confirming a particular observed efficacy result.
In general, a sample-size calculation is not an estimate of the probability that a completed trial’s result is true, and it is not observed power. It is a planning exercise conditional on assumed effect size, variability or event frequency, significance level, allocation, and method. If the actual effect differs from the assumption, the operating characteristics of a design differ as well. No numerical planning illustration should be treated as an outcome of this trial.
Why can outcome dispersion matter?
For count outcomes, over-dispersion means that the observed variation is greater than expected under a simple model such as a Poisson distribution. If over-dispersion is ignored, uncertainty can be understated and statistical tests can be poorly calibrated. This is a general issue for count data, not a reported feature of this trial’s primary endpoint: the endpoint is described as a count of participants meeting a binary criterion, and the record does not report a model or a dispersion assessment. It would be inappropriate to assert that over-dispersion was present or that a particular correction was used.
The broader methodological point is that the endpoint definition, analysis population, missing-data handling, and model all affect interpretation. The registry record supplies the endpoint definition and the mITT population definition, but does not report enough analysis detail to reconstruct the efficacy analysis. Any fuller statistical interpretation would require the actual arm-level outcome data and the analysis methods used.
10. Multiplicity, Missing Data and Analysis Populations
The registry record lists a primary outcome assessed at 48 weeks and secondary outcomes concerning changes in quantitative HBs antigen at week 12 and week 24. It also indicates that outcome reporting includes several categories or time points rather than a single primary comparison. When a study examines multiple outcomes, time points, groups, or analysis choices, the chance of at least one apparently notable result can increase. This is the general reason statistical plans often specify which outcome is primary and how multiplicity will be handled.
A multiplicity adjustment or prioritization strategy is not reported in the registry record. Nor does the record describe whether any interim analyses were planned or conducted. It would be inappropriate to infer either that adjustments were made or that interim testing occurred. The number of analyses listed is three, but their exact relationship to the outcome categories and the reporting approach is not clear enough to reconstruct a testing strategy.
The primary analysis population is defined as all randomized participants with at least one post-baseline measurement. The record does not report how many randomized participants lacked such a measurement, how missing measurements were handled, or whether sensitivity analyses were performed. It also does not report whether the analysis used imputation, a complete-case approach, or another method. Missing-data assumptions matter because participants without outcome measurements may differ from those observed; the direction and size of any resulting bias cannot be determined without information about the missingness and analysis.
The registry record does not describe a full intention-to-treat analysis, a per-protocol analysis, or other analysis populations beyond the stated mITT definition. It therefore does not establish whether results were compared across multiple populations or whether deviations from assigned treatment were addressed. These omissions limit assessment of robustness and multiplicity, but do not imply that particular methods were or were not used outside what the record reports.
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 |
|---|---|---|---|
| Treatment Group | 13 | 112 | 11.6% |
| Control Group | 4 | 58 | 6.9% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Treatment Group | 0 of 112 |
| Control Group | 0 of 58 |
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 |
|---|---|
| Treatment Group | 106 of 112 |
| Control Group | 20 of 58 |
Most frequent serious adverse event terms
| Event term | Organ system | Treatment Group | Control Group |
|---|---|---|---|
| Contusion | Injury, poisoning and procedural complications | 1 of 112 | 0 of 58 |
| Aortic valve stenosis | Cardiac disorders | 1 of 112 | 0 of 58 |
| Meniscus injury | Injury, poisoning and procedural complications | 1 of 112 | 0 of 58 |
| forearm fracture | Injury, poisoning and procedural complications | 1 of 112 | 0 of 58 |
| facial bones fracture | Injury, poisoning and procedural complications | 1 of 112 | 0 of 58 |
| retinal haemorrhage | Eye disorders | 1 of 112 | 0 of 58 |
| internal fixation of fracture | Surgical and medical procedures | 1 of 112 | 0 of 58 |
| coronary artery disease | Cardiac disorders | 1 of 112 | 0 of 58 |
| renal colic | Renal and urinary disorders | 1 of 112 | 0 of 58 |
| chlamydial infection | Infections and infestations | 1 of 112 | 0 of 58 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Treatment Group | Control Group |
|---|---|---|---|
| fatigue | General disorders | 48 of 112 | 2 of 58 |
| headache | Nervous system disorders | 40 of 112 | 0 of 58 |
| arthralgia | Musculoskeletal and connective tissue disorders | 31 of 112 | 0 of 58 |
| nasopharyngitis | Infections and infestations | 28 of 112 | 3 of 58 |
| pyrexia | General disorders | 25 of 112 | 0 of 58 |
| myalgia | Musculoskeletal and connective tissue disorders | 19 of 112 | 0 of 58 |
| back pain | Musculoskeletal and connective tissue disorders | 15 of 112 | 2 of 58 |
| abdominal pain upper | Gastrointestinal disorders | 11 of 112 | 6 of 58 |
| alopecia | Skin and subcutaneous tissue disorders | 17 of 112 | 0 of 58 |
| influenza like illness | General disorders | 13 of 112 | 2 of 58 |
Serious events with the highest arm-level rate: pyelonephritis (1.7%), urinary tract infection (1.7%), foot deformity (1.7%), endometrial hyperplasia (1.7%), vaginal haemorrhage (1.7%).
The registry record lists serious adverse event counts for 112 participants at risk in the treatment group, with 13 affected, and 58 participants at risk in the control group, with 4 affected. It also lists other adverse event counts: 106 affected in the treatment group and 20 in the control group, with the same group denominators. Deaths are listed as 0 in each group. These are descriptive counts from the registry record; no additional rates or comparisons are calculated.
The record lists pyelonephritis, urinary tract infection, foot deformity, endometrial hyperplasia, vaginal haemorrhage, and nasal tubinate hypertrophy among the top serious adverse event terms, each with a reported value of 1.7%. The record does not provide enough context to determine from these entries whether terms represent distinct participants, recurrent events, or a complete list of serious events. They should not be read as an exhaustive catalogue or as proof that every listed term occurred only once.
Comparing safety counts requires attention to how events were defined, how long participants were followed, and whether counts refer to people or event episodes. The registry record does not report all of those details or a formal between-group safety analysis. The counts alone do not establish causation or a treatment effect on safety.
12. What the Result Does, and Does Not, Mean
The registry record makes the trial’s main question clear: whether adding pegylated interferon alfa-2a to ongoing nucleos(t)ide treatment changes the percentage reaching a specified HBsAg decline after 48 weeks. It also identifies a randomized, open-label, parallel-group design and defines the primary analysis population. Those details allow readers to understand what comparison was intended.
What the record does not provide is a single numerical primary efficacy result. Without the response counts or percentages in each group, there is no reported estimate of the between-group difference to interpret. Without an interval estimate, the precision of any effect cannot be judged. Without a reported analysis method and multiplicity approach, readers also cannot evaluate how the primary result was derived or how it relates to the other outcome measures.
These absences should not be turned into a claim that the intervention did or did not change the outcome. Missing numerical results in the registry record are not equivalent to a null effect, and a completed trial does not by itself establish the direction or size of an effect. The secondary outcome results are also not reported in the registry record, so they cannot resolve the uncertainty about the primary comparison.
The safety information has a different role. Counts of serious and other adverse events, and the listed death counts, describe reported events by group. They do not answer the efficacy question, and without fuller definitions and analysis details they do not establish that an event was caused by a treatment strategy or that one strategy had a different safety profile.
The appropriate reading is therefore bounded: the record documents the trial question, treatment contrast, broad design, endpoint, analysis-population definition, and selected safety information. It does not allow a quantitative assessment of efficacy or a full assessment of statistical robustness. Further interpretation would require the arm-level results, uncertainty estimates, and analysis details, none of which are reported in the registry record.
13. Why This Trial Matters Statistically
This trial is statistically useful to examine because it combines a randomized treatment comparison with a threshold-based laboratory endpoint. Randomization defines a comparative framework: outcomes in the two assigned groups can be contrasted, subject to adherence, missing data, and analysis choices. The threshold endpoint makes the target response explicit, while also illustrating the information lost when a continuous measurement is converted into a yes-or-no outcome.
The open-label design is another useful point for statistical reading. Knowledge of assignment can influence behavior, follow-up, co-interventions, or outcome assessment in some settings. A laboratory-based measure may limit some forms of subjective assessment, but the registry record does not say whether laboratory personnel were masked or what safeguards were used. The design label alone cannot establish the size or direction of any bias.
The record also demonstrates why an endpoint definition is not the same as an endpoint result. The registry describes the 48-week question and the secondary time points, but does not report a single primary comparison. Readers should distinguish a clearly specified estimand—the contrast the study seeks to describe—from the estimate and uncertainty needed to judge the observed data.
Finally, the safety counts show why denominators, event definitions, and analysis populations matter. Descriptive numbers can orient interpretation, but comparisons require context about follow-up and event counting. This trial is therefore a practical example of how design information can be informative even when reported outcome data are insufficient for a quantitative efficacy interpretation.
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.
A central limitation for interpreting this trial from the registry record is the absence of a single numerical primary efficacy comparison. The record describes the response threshold and follow-up time but does not report arm-specific response counts or percentages, an effect estimate, an uncertainty interval, or a p-value. As a result, neither the magnitude nor the precision of the primary comparison can be assessed.
The outcome reporting is indicated to involve several categories or time points rather than one comparison. The registry record does not explain how these results relate to the stated primary endpoint or how multiplicity was addressed. The statistical analysis plan, including the method used for the binary outcome, is not reported. The record also does not report an approach to missing data, sensitivity analyses, or additional analysis populations.
The mITT population is defined as randomized participants with at least one post-baseline measurement, but the number included in that population is not reported. The record does not state how many participants lacked post-baseline data or describe treatment adherence, withdrawals, protocol deviations, or their handling in analysis. These details would help assess how closely the analyzed population represents the randomized groups.
The trial is open-label, and the registry record does not describe laboratory masking or other procedures that may affect outcome assessment. The background nucleos(t)ide regimens are also not detailed. The record does not provide a sample-size justification, so it is not possible to assess the planned precision or statistical power from the trial’s own design rationale.
Safety interpretation is limited by the available counts and the lack of reported definitions, follow-up detail, or a formal comparative analysis. These reporting limitations do not establish that the trial had methodological flaws; they define what cannot be evaluated from the registry record.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Peg-interferon ADDed to an Ongoing Nucleos(t)Ide Based Treatment in Patients With Chronic Hepatitis B to Induce Decrease of HBs-Antigen — NCT01524679.
- Registry record last updated 2020-02-18; status last verified 2020-02.
- Results first posted 2020-02-18.
- 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 completed, randomized, open-label, parallel-group phase IIb trial with enrollment of 170 participants with chronic HBeAg-negative hepatitis B. Participants were receiving oral antiviral treatment and had a nondetectable viral load for at least 12 months. The treatment group received pegylated interferon alfa-2a, 180 μg once weekly for 48 weeks, added to ongoing nucleos(t)ide-based treatment; the control group continued nucleos(t)ide-based treatment alone.
The primary endpoint concerned the percentage reaching at least a 1log10 decline in quantitative HBsAg after 48 weeks. The primary analysis population was defined as all randomized participants with at least one post-baseline measurement. Secondary outcomes concerned quantitative HBs antigen changes at week 12 and week 24. A single numerical primary comparison and its uncertainty are not reported in the registry record. Safety entries include serious and other adverse event counts by group and zero deaths in each group.