A Study of PVP001, PVP002, and PVP003 in Healthy Adults and PVP001 and PVP002 in Adults With Celiac Disease: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for A Study of PVP001, PVP002, and PVP003 in Healthy Adults and PVP001 and PVP002 in Adults With Celiac Disease (NCT03701555), a randomized phase 1 study. The primary outcome is Part 1: Number of Participants Reporting One or More Treatment Emergent Adverse Events (TEAEs) for PvP001 and PvP002.

2. Clinical Question

The trial was intended to assess safety, tolerability, and pharmacokinetics of the study medicines, with gluten degradation activity also assessed for PVP003. The posted primary endpoint is narrower than those broad aims: it reports counts of participants with one or more treatment-emergent adverse events for PVP001 and PVP002 in Part 1. The registry record does not report a primary efficacy question about symptoms, disease control, or clinical benefit.

The results should therefore be read as descriptive safety observations in small, separate cohorts. Differences in the reported counts do not, by themselves, show that a medicine caused more or fewer events than placebo. The groups include healthy adults and participants with celiac disease, and the record does not describe a pooled estimate or a statistical comparison for the primary endpoint.

3. Trial Design

This was a Phase 1, randomized, single-masked, sequential study with four parts. The registry record reports enrollment of 139 and status as completed. It lists a start date of 2018-06-19 and a primary completion date of 2021-01-31. These overall study details do not mean that all enrolled participants contributed to every part or every outcome.

Part 1 used separate cohorts in healthy participants and participants with celiac disease. The cohorts received a single dose of PVP001 placebo, PVP001 at 100 mg, 300 mg, or 900 mg, or a maximum feasible dose of PVP002. The listed primary outcome concerns this part only. Its results are reported separately for each cohort, including healthy-participant and celiac-disease cohorts.

Part 2 involved healthy participants and included PVP001 and PVP002 regimens, placebo groups, and a PVP001 regimen following 7 days of PPI treatment. Part 3 examined PVP003 in healthy participants in relation to standardized gluten-containing or gluten-free meals, with different meal timing and pretreatment conditions described for the cohorts. Part 4 assessed multiple doses of PVP003 or placebo in healthy participants. These distinct conditions make the study a set of sequential investigations, not one uniform comparison across all parts.

Randomization and single masking are recorded, but details of the allocation procedure and the identity of the masked parties are not reported in the registry record. The registry record also does not report a common control group across all cohorts, a protocol-level statistical analysis plan, or a sample-size justification. Because treatments and study conditions varied across parts, the Part 1 primary counts should not be treated as a direct comparison of every medicine or dose in the full study.

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: Healthy participants and participants with Celiac Disease (CeD) were enrolled in this 4-part study. In Part 1, healthy participants and participants with CeD were enrolled and in Parts 2, 3 and 4 only healthy participants were enrolled to receive PVP001 (TAK-062 liquid), PVP002 (TAK-062 capsule), and PVP003 (TAK-062 tablet) formulation or matching-placebo.

Only the first 6 of 36 groups are shown.

Part 1 (Day 1)

Part 2 (Day 1)

Reasons for not completing this period:

Part 3 (Day 1)

Reasons for not completing this period:

Part 4, Period 1 (Days 1 to 5)

Analysis population for the primary outcome, as defined in the registry: Safety population included all participants who received at least one dose of study drug. As planned, this outcome measure was assessed only for Part 1 of the 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.

Population: The safety population included all participants who received at least 1 dose of study drug.

Only the first 6 of 37 groups are shown.

6. Primary Endpoint

The registry lists the primary outcome as Part 1: Number of Participants Reporting One or More Treatment Emergent Adverse Events (TEAEs) for PvP001 and PvP002, measured over Cohort Treatment Day up to 5 days after 24-hour safety assessment on Day 2 (up to Day 7).

The primary endpoint is the number of participants reporting one or more treatment-emergent adverse events for PVP001 and PVP002 in Part 1. The timeframe is from cohort treatment through 5 days after the 24-hour safety assessment on Day 2, up to Day 7. The safety population includes participants who received at least one dose of study drug, and the registry states that this outcome was assessed only in Part 1.

This is a binary participant-level concept summarized as a count: each participant either reported at least one qualifying event during the stated period or did not. A participant with multiple events is still represented as a participant reporting one or more events for this endpoint. The count does not describe the number of separate event episodes, their severity, or their relationship to treatment. Those details require other results and definitions.

In general, early-phase studies use adverse-event monitoring to describe tolerability and identify safety observations during exposure. A count is easy to interpret as a tally of participants, but it does not by itself account for differences in group size or provide a measure of uncertainty. Rates, effect estimates, and confidence intervals can help with comparisons when appropriate data and a suitable analysis are available; the registry record does not list such a comparative analysis for this endpoint.

The posted Part 1 counts are 0.0 in each of the five healthy-participant groups. Among the celiac-disease groups, the counts are 3.0 for PVP001 placebo, 0.0 for PVP001 100 mg, 2.0 for PVP001 300 mg, 1.0 for PVP001 900 mg, and 1.0 for PVP002 600 mg. The listed group sizes are 3.0 for each of those celiac-disease groups except the PVP002 600 mg group, which lists 1.0. With groups this small, the counts are descriptive observations rather than stable estimates of comparative risk.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry reports a participant count for a binary outcome: whether a participant reported one or more treatment-emergent adverse events within the stated period. The posted value is a count rather than a modeled risk, risk difference, odds ratio, or other comparative effect. The group size supplies context for the count, but a count alone does not measure uncertainty or adjust for group size.

What does a participant count mean?

For a binary endpoint, each participant is classified according to whether the endpoint occurred. Here, a participant is counted if at least one treatment-emergent adverse event was reported in the endpoint window. This approach avoids treating multiple events in one participant as multiple participants. It also means that the count does not convey how many events an affected participant had, what kinds of events occurred, or their duration.

In general, researchers may summarize a binary endpoint using a proportion as well as a count. A proportion can make groups of different sizes easier to compare descriptively, but it remains an estimate subject to uncertainty. No new proportions or contrasts are calculated for this explanation. The record's small cohort sizes make any apparent difference especially sensitive to the experience of individual participants.

Why do small groups limit comparisons?

With a small denominator, a single participant can materially change a group summary. When few or no events are observed, standard large-sample approximations can also be unreliable. General approaches for sparse binary data can include exact methods or models that are appropriate for small samples, but the registry record does not report which method, if any, was used to compare these groups. It lists no outcome analyses, and no inferential comparison for the primary result is reported.

The cohorts also are not interchangeable simply because they share an endpoint. They include healthy adults and adults with celiac disease, and differ in assigned treatment, dose, and study context. A sound comparative analysis would need to define which groups are being contrasted and account for the design and population. The posted counts do not supply such an analysis. Pooling the groups without a prespecified rationale could conceal meaningful differences in population or regimen.

What would an uncertainty interval add?

In general, a confidence interval communicates the precision of an estimated quantity under stated assumptions. For a treatment comparison, the estimate might describe a difference between groups, while its interval conveys how uncertain that difference is. A wide interval indicates limited precision; an interval that includes no difference does not prove equivalence. The record does not report a confidence interval or a comparative estimate for the primary endpoint, so the treatment contrast and its precision cannot be assessed from the primary counts.

A p-value, in general, assesses how compatible the observed data are with a specified null model, subject to the model and analysis choices. It is not a measure of effect size or clinical importance. No p-value for the primary endpoint is reported. The absence of a reported test should not be replaced by an informal test based on the raw counts.

How should planning illustrations be read?

The statistical materials include sample-size planning illustrations based on the observed effect, with assumptions of a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. These are planning illustrations rather than the trial's original design justification or observed power. In general, such calculations show what sample size might be needed under a chosen assumed effect and analysis framework. They do not show that a study with a given observed sample size had a particular probability of detecting its actual effect. The registry record does not report the trial's own sample-size justification.

Any planning result based on an observed effect is especially uncertain when the original groups are small. The observed effect may be unstable, and planning from it does not remove uncertainty or establish that the effect will recur. The illustrations should not be treated as additional trial outcomes or as evidence for treatment benefit.

The registry record describes a randomized, single-masked, sequential design, but it does not provide enough detail to reconstruct allocation, masking, analysis, or handling of repeated observations across the study parts. It also does not report the statistical methods used for pharmacokinetic measures, anti-drug antibodies, or the other listed outcomes. General statistical concepts can explain how such outcomes might be analysed, but no particular method should be attributed to this trial without a registry report.

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("Part 1, (1A-1): PvP001 Placebo", "Part 1, (1B-1): PvP001 100 mg", "Part 1, (1C-1): PvP001 300 mg", "Part 1, (1D-1): PvP001 900 mg", "Part 1, (1E-1): PvP002 600 mg", "Part 1, (1A-2): PvP001 Placebo")
n      <- c(3, 3, 3, 3, 3, 3)
events <- c(0, 0, 0, 0, 0, 3)
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  Part 1, (1A-1): PvP001 Placebo  3  0  0.0  0.0  70.8  0.0  56.1  0.6  60.2
ARM  Part 1, (1B-1): PvP001 100 mg  3  0  0.0  0.0  70.8  0.0  56.1  0.6  60.2
ARM  Part 1, (1C-1): PvP001 300 mg  3  0  0.0  0.0  70.8  0.0  56.1  0.6  60.2
ARM  Part 1, (1D-1): PvP001 900 mg  3  0  0.0  0.0  70.8  0.0  56.1  0.6  60.2
ARM  Part 1, (1E-1): PvP002 600 mg  3  0  0.0  0.0  70.8  0.0  56.1  0.6  60.2
ARM  Part 1, (1A-2): PvP001 Placebo  3  3  100.0  29.2  100.0  43.9  100.0  39.8  99.4

11. Multiplicity, Missing Data and Analysis Populations

The study has multiple parts and multiple outcomes. The registry lists 36 outcome measures and reports 21 secondary outcomes. These include pharmacokinetic measures for PVP001 and PVP002, anti-drug antibodies, maximum tolerated dose, and treatment-emergent and serious adverse events. With many outcomes or comparisons, the chance of at least one apparently unusual result can increase. In general, a prespecified multiplicity strategy can define which outcomes are confirmatory and how interpretation should account for multiple testing. Such a strategy is not reported in the registry record.

The primary outcome's population is defined as the safety population: participants who received at least one dose of study drug. The registry says the primary outcome was assessed only for Part 1. It does not report an analysis population definition for every secondary outcome or explain how participants with incomplete outcome data were handled.

Missing-data methods are not reported in the registry record. The available primary results give group sizes and participant counts, but do not explain whether any outcome status was missing, how missing status was classified, or whether any participants were excluded from the endpoint analysis. No assumptions about missingness or imputation should be inferred from the reported counts.

The record lists no outcome analyses, and it does not report a formal statistical analysis plan for the comparisons discussed in the study description. The absence of reported multiplicity, missing-data, and analysis-population details limits the ability to assess whether the posted outcomes were selected or analysed according to a prespecified framework. This does not change the descriptive meaning of the counts, but it limits stronger inferential conclusions.

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 serious adverse-event summary reports 0 affected participants for serious events in every listed group, and it reports 0 deaths in every listed group. The number at risk varies by group, so these are group-specific observations rather than a single study-wide estimate. No serious adverse-event terms are listed in the registry summary.

Serious adverse events are not the same as all treatment-emergent adverse events. The primary endpoint counts participants reporting one or more treatment-emergent adverse events, while the serious-event summary reports events in the serious category. The primary results include nonzero counts in some celiac-disease cohorts, while the serious-event counts remain 0. These statements can both be true because the endpoint categories differ.

In general, a zero serious-event count means none was recorded among the participants at risk in that listed group during the reported study observation. It does not establish that serious events cannot occur, particularly when groups are small. The registry record does not provide enough information to estimate a precise underlying risk or compare serious-event risk between treatments. Nor does a zero count describe the severity or frequency of non-serious events beyond the separate participant counts reported for the primary endpoint.

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

The results establish what was recorded in these study cohorts for the primary safety endpoint: the participant counts with one or more treatment-emergent adverse events during the specified Part 1 timeframe. They also show that no serious adverse events or deaths were reported in the listed safety groups. These are descriptive findings from the registry record, not a definitive ranking of treatments.

The counts do not establish a causal difference between active treatment and placebo. The cohorts are small and separated by population, dose, and study context, and the registry does not report a comparative estimate, confidence interval, or hypothesis test for this endpoint. A difference in counts is not equivalent to evidence of a treatment effect. A zero count is not proof of zero risk.

The results also do not show whether PVP001, PVP002, or PVP003 improves celiac disease or produces a clinical benefit. Although the study's stated aims include pharmacokinetics and, for PVP003, gluten degradation activity, results for those outcomes are not reported in the registry record in the information summarized for the primary endpoint. The primary endpoint is a safety measure, not a measure of gluten breakdown or disease symptoms.

Nor should the Part 1 results be generalized automatically to the other study parts or to people outside the studied cohorts. Parts 2 through 4 involved different regimens and study conditions, and the primary endpoint was assessed only in Part 1. The registry record's overall enrollment does not indicate how many participants contributed to any one cohort or outcome.

In general, early-phase observations can describe events and inform later research questions, but they are not a substitute for adequately sized comparative evidence. The record does not report a sample-size justification, a multiplicity plan, or the analysis details needed to interpret formal comparisons. The posted data therefore support a limited, cohort-specific description and not a conclusion about efficacy or comparative safety.

14. Why This Trial Matters Statistically

This trial is statistically instructive because it combines a sequential, multi-part design with several populations, formulations, doses, and study conditions. The primary endpoint is intentionally descriptive: it counts participants with one or more treatment-emergent adverse events in Part 1. Keeping that scope clear helps prevent results from one cohort from being mistaken for a common comparison across the entire study.

The record also illustrates why denominators matter. The same count can carry different meaning depending on the group size, and observations in very small groups are imprecise. A count of zero is informative about what was recorded in that group, but it cannot show that the underlying event risk is absent. Conversely, a nonzero count in a small group should not be treated as a stable estimate for a wider population.

Randomization is an important design feature, but it does not make every group in a sequential study directly comparable. The cohorts differ in population and regimen, and the record does not report a formal analysis that joins them into a single treatment contrast. Recognizing the design structure is therefore essential when reading the posted results.

Finally, the trial highlights the distinction between a study's broad aims and its posted primary result. Safety, tolerability, pharmacokinetics, and gluten degradation activity appear in the study description, while the primary result addressed is a Part 1 adverse-event count. Separate outcome-specific results and analyses are needed to answer the other questions. Statistical interpretation begins by matching each result to the population, endpoint, and time period it actually describes.

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.

The primary endpoint is limited to Part 1 even though the study had four parts and included additional medicines and regimens. The posted primary counts cannot answer whether results were similar in Parts 2, 3, or 4. Nor can results from the healthy-participant cohorts be assumed to apply to adults with celiac disease, or the reverse.

Group sizes are small, including a listed size of 1.0 in the celiac-disease PVP002 600 mg group. Counts from such groups are highly sensitive to individual observations and provide little precision for estimating event frequency. The record does not report confidence intervals or comparative estimates for the primary endpoint.

The registry does not report the allocation procedure, who was masked, handling of missing outcomes, or a statistical analysis plan. It also does not report a sample-size justification or multiplicity strategy. These omissions prevent a full assessment of the planned statistical framework and how it relates to the posted results.

The event count does not describe event types, severity, duration, or attribution to study treatment. The separate serious-event summary reports no serious adverse events or deaths in the listed groups, but that finding does not characterize all non-serious events. Results for the study's pharmacokinetic and gluten degradation aims are not reported in the registry record in the information summarized for the primary endpoint. As a result, those aims cannot be evaluated from these primary safety counts.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: A Study of PVP001, PVP002, and PVP003 in Healthy Adults and PVP001 and PVP002 in Adults With Celiac Disease — NCT03701555.
• Registry record last updated 2023-04-04; status last verified 2022-06.
• Results first posted 2023-04-04.
• 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 a completed, randomized, single-masked, sequential Phase 1 study of PVP001, PVP002, and PVP003 in healthy adults and adults with celiac disease. Overall enrollment is listed as 139. The study had four parts, with the primary adverse-event endpoint assessed only in Part 1 among participants who received at least one dose.

Part 1 results report participant counts for one or more treatment-emergent adverse events through the stated follow-up period. Counts are zero in the listed healthy-participant groups and vary across the celiac-disease groups. The serious adverse-event summary reports no serious events or deaths in the listed groups.

The registry record does not report a formal comparative analysis for the primary endpoint, nor does it report the sample-size justification, missing-data methods, or multiplicity plan. The primary counts are descriptive and do not establish comparative safety or efficacy. Results for pharmacokinetics and PVP003 gluten degradation activity are not reported in the registry record in the information summarized for this endpoint.