Transplanting Hepatitis C Lungs Into Negative Lung Recipients: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Transplanting Hepatitis C Lungs Into Negative Lung Recipients (NCT03724149), a na phase 1, phase 2 study. The primary outcome is Subject Sustained Virologic Response (SVR-12) at 12-weeks Post-treatment.

2. Clinical Question

The clinical question combines a transplant setting with antiviral treatment after transplantation. It concerns recipients who are hepatitis C-negative before receiving lungs from hepatitis C-positive donors, followed by treatment intended to address hepatitis C infection. The record describes the study as assessing the safety and effectiveness of this approach. Its primary measure is a participant count based on a virologic result after treatment, rather than a comparison of treatment groups.

Because the trial has a single group, the central statistical question is descriptive: what outcome was recorded among the participants treated after transplantation? A single-group result can describe what happened in the study group, but without a concurrent control group it cannot, by itself, separate the effects of antiviral treatment from other influences or establish a comparative treatment effect. The registry record does not provide the primary outcome count, the number treated for that outcome, or a statistical analysis. It therefore does not answer the primary question with a reported result.

3. Trial Design

The registry lists this as a Phase 1 and Phase 2, open-label, single-group trial. Allocation is recorded as NA, and masking is listed as none. The design is not a randomized comparison: the registry’s own study description has no like-for-like control group. The record gives an enrollment of 10. That enrollment figure does not establish how many participants were treated or included in the primary endpoint denominator.

The study focuses on hepatitis C-negative patients on the lung transplant waitlist who receive lungs from hepatitis C-positive donors and then receive direct-acting antiviral treatment. Zepatier and Epclusa are named as drug interventions. The primary outcome definition also refers to another appropriate antiviral treatment, so the registry record does not establish that every participant received the same named drug. The arm is described as direct-acting antiviral treatment for HCV; further details about treatment assignment, regimen selection, or treatment duration are not reported in the registry record.

The recorded start date is 2018-12-12, the primary completion date is 2021-12-31, and the study status is completed. These entries describe the trial’s registry status and milestone dates; they do not supply an outcome analysis. The record lists two outcome measures and zero analyses. It does not report the protocol’s statistical plan, whether interim analyses were planned or conducted, or how the outcome data were analyzed.

The single-group structure is important for interpretation. The study can provide an account of outcomes observed in the treated group, if those outcomes are reported, but there is no concurrent group in this record to support a randomized contrast. Consequently, comparisons with external experience would require information and assumptions not included in the registry record. The primary outcome result and its uncertainty are not reported in the registry record.

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

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.

6. Primary Endpoint

The registry lists the primary outcome as Subject Sustained Virologic Response (SVR-12) at 12-weeks Post-treatment, measured over Baseline to 12 weeks.

The primary endpoint is the number of participants with sustained virologic response at 12 weeks after treatment, abbreviated SVR-12. The record defines this as an undetectable HCV RNA in serum 12 weeks after completing treatment for hepatitis C. It describes the outcome as a count of participants and gives the timeframe as baseline to 12 weeks. The associated rate is defined as the number of subjects with SVR divided by the number of subjects treated after lung transplantation.

SVR-12 is used as a measure of virologic status after treatment rather than as a measure of symptoms, lung function, transplant survival, or quality of life. A post-treatment assessment provides a specified time point at which the presence or absence of detectable HCV RNA can be classified according to the registry definition. That makes the endpoint interpretable as a binary participant outcome: each participant either meets the stated definition or does not, assuming the necessary measurement is available.

The registry record does not report the number of participants who met the definition, the number treated who formed the denominator, or the resulting rate. It also does not report how missing HCV RNA measurements were handled. Without those details, the endpoint’s observed frequency and its precision cannot be assessed from this record. The defined endpoint should therefore be distinguished from a reported result: the former is present, while the latter is not reported in the registry record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

Statistical methods help distinguish an outcome definition from an estimate, an estimate from its uncertainty, and an observed group result from a treatment comparison. In this trial record, the endpoint is defined, but its result and analysis are not reported. That distinction limits what can be concluded from the available information.

What does a participant count mean?

The primary outcome is a count: the number of treated participants who have undetectable HCV RNA at the stated post-treatment assessment. A count is a direct way to report how many observed participants meet a criterion. The registry also defines a rate by relating that count to the number treated after transplantation. For interpretation, both parts matter. The count alone does not show how common the outcome was unless its denominator is known, and the denominator must refer to the participants eligible for that endpoint rather than being assumed from the enrollment field.

For a binary outcome, the underlying observation for each participant is classified into one of two categories: meeting the endpoint definition or not meeting it. Statistical analysis can use these classifications to estimate the proportion meeting the definition. Such an estimate is subject to sampling uncertainty: results from a study group are not an exact measure of what would be observed in every comparable group. A confidence interval is one general way to express that uncertainty, showing a range of values compatible with the data under the method’s assumptions. No confidence interval for SVR-12 is reported in the registry record.

Why does the design affect interpretation?

In a randomized comparison, treatment groups can be contrasted under the design’s allocation process. This study is instead listed as single-group, open-label, with allocation recorded as NA. Its primary result, if available, would be a description of the group receiving the treatment approach. It would not be a randomized treatment contrast. Statistical adjustment can sometimes account for measured characteristics in observational comparisons, but the registry record reports no such analysis. General statistical principles cannot supply a comparison that the study design and record do not contain.

Open-label means masking is listed as none. In general, awareness of treatment can affect aspects of care, assessment, or reporting, depending on the outcome and study conduct. The primary endpoint is defined through HCV RNA measurement, but the registry record does not report laboratory procedures, assessment blinding, or other safeguards. No claim about their presence or absence beyond the recorded masking status is warranted.

How should precision be considered?

Precision concerns how much uncertainty surrounds an estimate. It depends on the amount and pattern of information available, including the number of participants who contribute an observed endpoint. A small group can yield an estimate that is sensitive to individual outcomes, so uncertainty is important when interpreting counts or rates. The registry lists enrollment of 10, but the number treated and the number with an available SVR-12 assessment are not reported. A primary estimate and its precision therefore cannot be reconstructed from the enrollment entry.

General methods for binary outcomes may use exact or approximate intervals, or model-based approaches, depending on the analysis plan and data. The choice can matter when data are sparse. The registry record does not specify a statistical method, confidence level, or interval procedure for the primary outcome. No method should be attributed to the investigators without that information.

What do the sample-size assumptions describe?

The record includes assumptions for planning illustrations: a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation, with an effect defined as a stated fraction of an observed effect. Those are planning assumptions, not evidence that this trial used a two-arm design. The actual trial is listed as single-group and not a randomized comparison. The illustrations are not the trial’s own design justification, and any resulting sample-size values would be planning quantities rather than observed findings or observed power. The registry record does not report a sample-size justification for the trial.

Planning calculations based on a fraction of an observed effect are conditional on the effect used as their reference and on the assumptions specified for the calculation. They do not establish that a future study will achieve a particular result. They also cannot replace a reported estimate and uncertainty from the present study. Since the primary outcome result is not reported in the registry record, the observed effect itself cannot be assessed from this record.

What can be concluded from the listed analyses?

The registry lists zero analyses. This means no statistical analysis is presented in the record for review; it does not establish what analyses may have been conducted outside the record. No inferential result, such as a p-value, adjusted effect, or interval estimate, can be evaluated. The appropriate reading is therefore descriptive and limited: the record specifies the trial design and SVR-12 definition, and it lists certain safety counts, while leaving the primary efficacy analysis unavailable.

10. Exact Estimates for Each Arm

No two-arm comparison is shown for this trial, but each arm's result can still be summarized with exact interval estimates computed from the posted counts. The Clopper-Pearson interval is exact and conservative; the Wilson interval is a common closer-to-nominal alternative; the Bayesian credible interval uses a uniform Beta(1, 1) prior. For small groups the three can differ noticeably.

R code and output

arm    <- c("Direct-acting Antiviral Treatment for HCV")
n      <- c(10)
events <- c(10)
for (i in seq_along(n)) {
  ci <- binom.test(events[i], n[i])$conf.int          # Clopper-Pearson exact interval
  cr <- qbeta(c(0.025, 0.975), 1 + events[i], 1 + n[i] - events[i])   # Bayesian, uniform Beta(1,1) prior
  wi <- (function(x, n) { p <- x / n; z <- qnorm(0.975); d <- 1 + z^2 / n
    c((p + z^2 / (2 * n) - z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d, (p + z^2 / (2 * n) + z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d) })(events[i], n[i])
  cat(sprintf("ARM|%s|%d|%d|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f\n", arm[i], n[i], events[i], 100 * events[i] / n[i],
              100 * ci[1], 100 * ci[2], 100 * wi[1], 100 * wi[2], 100 * cr[1], 100 * cr[2]))
}

ARM  Direct-acting Antiviral Treatment for HCV  10  10  100.0  69.2  100.0  72.2  100.0  71.5  99.8

11. Multiplicity, Missing Data and Analysis Populations

Multiplicity arises when a study assesses multiple outcomes, time points, groups, or statistical tests. If many hypotheses are tested, the chance of finding an apparently notable result by chance can increase unless the analysis plan addresses that issue. The registry lists two outcome measures, but it does not report a multiplicity strategy, a hierarchy of outcomes, or a statistical analysis plan. The primary outcome is identified by name, but the record does not explain how it would be treated in relation to the other outcome measure. Any adjustment, prioritization, or testing sequence is therefore not reported in the registry record.

Missing data matter because a participant’s endpoint status cannot be classified from an unavailable measurement without an analysis rule. The primary endpoint requires HCV RNA assessment after treatment, and its denominator is described as participants treated after lung transplantation. The record does not report how many participants had an available measurement, whether any measurements were missing, or how missing endpoint data were handled. It does not state whether participants without an assessment were excluded, counted as not meeting the endpoint, or addressed through another method. No such approach should be assumed.

Analysis populations are also not described. The registry does not state whether the primary analysis included all enrolled participants, only treated participants, or a defined subset. The endpoint description refers to participants treated after transplantation, but it does not provide the count or a fuller population rule. The enrollment of 10 should not be treated as the primary analysis denominator without an explicit statement. The number of analyses is listed as zero, and no statistical plan or analysis population is reported in the registry record.

12. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

Deaths

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 0% reporting threshold.

Most frequent non-serious adverse event terms

The registry lists the direct-acting antiviral treatment group with 10 participants at risk for serious adverse events and 0 affected. For other adverse events, it lists 10 at risk and 1 affected. The death count is 0. These are counts, not comparative estimates, and the group has no control arm in this trial record.

The serious adverse event count should be read as a descriptive report for the recorded group, not as proof that serious events are impossible or that the treatment approach has no safety risks. A zero count in a study group provides limited information about uncommon events. The record does not report a confidence interval or a comparative safety analysis.

The single other adverse event is not described by term in the registry’s list of top serious terms, which is empty. That absence does not establish what the event was, whether it was related to treatment, or how severe or persistent it was. The event’s nature, timing, and attribution are not reported in the registry record. The listed at-risk counts also should not be interpreted as confirming complete follow-up unless the record says so; follow-up details are not reported.

13. What the Result Does, and Does Not, Mean

The registry record documents a completed, open-label, single-group study of direct-acting antiviral treatment after lung transplantation from hepatitis C-positive donors to hepatitis C-negative recipients. It defines SVR-12 as an undetectable HCV RNA 12 weeks after treatment ends and identifies that outcome as the primary measure. It also lists safety counts for the treatment group. These registry entries describe the question, design, endpoint, and limited safety information recorded.

The record does not report the SVR-12 count, the denominator treated for the primary endpoint, or an estimated rate. It therefore does not establish how often participants met the primary endpoint. It also does not give an interval or other measure of precision, nor does it report a statistical analysis. The completion status is not a substitute for those missing outcome results.

The design also sets a boundary on interpretation. With a single group and no randomized comparator, any reported group outcome would not alone establish how that outcome compares with an alternative approach or what caused it. The record does not provide evidence for a comparative treatment effect. It likewise does not provide enough detail to characterize the other adverse event or to make a full assessment of safety.

These limits do not negate the value of a clearly defined endpoint or the descriptive safety counts. They identify what the registry record can support and what requires information not reported there. A treatment effect, a claim of equivalence, or a definitive safety conclusion should not be inferred from the available entries. The most accurate interpretation is that the trial’s design and intended primary measure are recorded, while its primary outcome result and statistical analysis are not reported in the registry record.

14. Why This Trial Matters Statistically

This study presents a useful statistical distinction between defining an outcome and reporting its result. SVR-12 is specified in operational terms: an undetectable HCV RNA in serum at a stated interval after completing treatment. That definition identifies what would count as a response. However, without the observed count and denominator, readers cannot determine the response rate or its precision. A well-defined endpoint is necessary for interpretation, but it does not replace outcome data.

The single-group design also makes the distinction between description and comparison especially important. A count among treated participants can describe what occurred in that group. It cannot, without a suitable comparator and appropriate analysis, answer how outcomes would differ under another treatment strategy. The registry records allocation as NA and describes no like-for-like control comparison. This prevents the primary question from being interpreted as a randomized efficacy contrast.

The safety entries illustrate a related point about sparse counts. Zero serious adverse events and zero deaths are the recorded counts, while one other adverse event is listed. Such entries can be informative descriptions, but their meaning depends on the population observed, completeness of follow-up, event definitions, and detail about event characteristics. Those elements are not fully reported in the registry record. The counts should therefore be read as limited descriptive evidence rather than as a complete safety evaluation.

Finally, planning calculations and trial results answer different questions. The stated sample-size assumptions concern hypothetical planning illustrations, whereas the trial record identifies a single-group design and does not provide a primary outcome analysis. Keeping those concepts separate helps avoid treating an assumed effect or a planning quantity as observed evidence. The registry record is valuable for identifying the study framework and endpoint, while its missing outcome analysis sharply limits statistical conclusions.

15. 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.

Several limitations specific to this record constrain interpretation. The primary endpoint is defined, but its observed count, denominator, and rate are not reported. The registry lists enrollment of 10, but does not state how many participants received treatment, had an evaluable post-treatment HCV RNA measurement, or contributed to the primary analysis. Enrollment therefore cannot stand in for the endpoint analysis population.

The single-group, open-label design has no concurrent control group described in the record. The study can describe outcomes in its treated group, but it does not provide a randomized comparison with an alternative. Allocation is recorded as NA, and masking is listed as none. The registry does not report methods that would support a comparative causal interpretation.

Further clinical and analytical details are absent. The record does not provide eligibility criteria beyond the broad population description, treatment assignment details, treatment duration, endpoint follow-up completeness, or handling of missing data. It does not report a sample-size justification, statistical analysis plan, interim analyses, analysis populations, or multiplicity procedures. The registry lists zero analyses, leaving no inferential result to assess.

Safety information is also limited to counts. The record does not describe the one other adverse event, report its timing or attribution, or provide fuller follow-up details. The top serious adverse terms list is empty, which does not provide additional characterization. These limitations mean that the available record supports only a narrow description of the design, endpoint definition, and listed safety figures.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Transplanting Hepatitis C Lungs Into Negative Lung Recipients — NCT03724149.
• Registry record last updated 2023-04-14; status last verified 2023-04.
• Results first posted 2023-04-14.
• 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.

19. Record Summary

The registry record describes NCT03724149, titled “Transplanting Hepatitis C Lungs Into Negative Lung Recipients.” The official title describes an open-label trial of direct-acting antiviral treatment in hepatitis C-negative patients receiving lung transplants from hepatitis C-positive donors. The study is listed as Phase 1 and Phase 2, single-group, open-label, and completed.

Enrollment is recorded as 10. The start date is 2018-12-12 and the primary completion date is 2021-12-31. Zepatier and Epclusa are listed as drug interventions. The primary outcome is participant SVR-12, defined by an undetectable HCV RNA 12 weeks after completing treatment. The primary outcome result and statistical analysis are not reported in the registry record.

The listed safety counts are 0 serious adverse events among 10 at risk, 1 other adverse event among 10 at risk, and 0 deaths. The record lists two outcome measures and zero analyses.