COVID-19 Outpatient Pragmatic Platform Study (COPPS) - Camostat Sub-Protocol: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for COVID-19 Outpatient Pragmatic Platform Study (COPPS) - Camostat Sub-Protocol (NCT04662073), a randomized phase 2 study. The primary outcome is For the Viral Domain: Change in Viral Shedding.

2. Clinical Question

The platform’s broader aims included assessing viral and clinical outcomes. Its description says each investigational product would collect data for both domain primary endpoints, while individual treatments were described in separate sub-protocols. For this camostat record, the specified primary endpoint is in the Viral Domain. The clinical question is therefore narrower than whether treatment changes all aspects of COVID-19: it concerns the recorded Day 10 viral-shedding count, and whether it can be compared with placebo in this trial record. The enrollment pattern prevents that comparison. The registry record does not report a randomized group contrast, an estimate of effect, or an uncertainty interval for the primary endpoint.

3. Trial Design

The camostat sub-protocol is part of the COVID-19 Outpatient Pragmatic Platform Study, described as a pragmatic, multi-arm, adaptive, Phase 2, blinded, randomized, placebo-controlled platform trial. The registry record characterizes the allocation as randomized, masking as double, and the model as parallel. These are design labels in the record; they do not establish that both treatment groups enrolled participants in this particular sub-protocol.

The intervention was camostat, and the comparator was matching placebo. Participants in either arm were to receive their assigned treatment for 10 days. The primary endpoint timeframe was also 10 days. The record names Stanford University as sponsor and gives the study status as terminated. It reports a start date of 2021-04-23 and a primary completion date of 2021-06-08.

The overall platform was intended to evaluate investigational treatments in adults with COVID-19 who were not sick enough to require hospitalization. It described two domains: a Viral Domain focused on viral shedding and a Clinical Domain focused on clinical outcomes. Listed secondary outcomes include time-to-resolution measures, time to viral cessation, indicators of hospitalization, emergency department visits or death, antibody development, and a negative SARS-CoV-2 RT-PCR test.

Enrollment for this camostat record was 2. The arm results report 2 participants in the camostat group and 0 in the matching-placebo group. Thus, although the record describes a randomized parallel comparison, the posted enrollment does not provide participants in both arms for a comparison. The reason the placebo arm had no enrollment is not reported in the registry record. Further details of the adaptive process, allocation procedure, masking procedures, or the operational conduct of the sub-protocol 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

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: No participants were enrolled in the placebo arm.

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: No participants were enrolled in the placebo arm.

6. Primary Endpoint

The registry lists the primary outcome as For the Viral Domain: Change in Viral Shedding, measured over 10 days.

The primary endpoint is described as the number of participants who had viral shedding at Day 10. It was based on self-collected nasal swab RT-PCR data, with change in SARS-CoV-2 shedding assessed through day 10 after transformation using a referenced standard curve. The endpoint is expressed as a count of participants, rather than as a continuous viral-load value in the posted arm summary.

Viral shedding is used as a virologic measure: it records whether viral material was detected according to the endpoint definition at the specified time. General statistical context: a binary count can summarize how many participants meet a defined condition, but interpreting it as a comparison requires data from the groups being compared and a clear denominator. The camostat arm reports 1 participant with viral shedding among 2 participants. The placebo arm has no enrolled participants, so its endpoint count and a between-arm contrast cannot be estimated from these results.

The broader platform description distinguishes viral outcomes from clinical outcomes. That distinction matters: a virologic endpoint is not itself a direct report of symptom resolution, hospitalization, or another clinical event. The registry record lists clinical outcomes as secondary measures, but does not post analyses for them. The reasons this endpoint was selected, the clinical interpretation threshold, and any detailed endpoint adjudication procedures are not reported in the registry record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry record identifies the study as randomized, double-masked, parallel, and Phase 2. These labels describe the stated design, but the posted result has only 2 participants in the camostat arm and none in the matching-placebo arm. The absence of placebo enrollment is decisive for interpreting the analysis: no comparison between the two arms can be calculated from the posted results. The record reports 0 analyses.

What does the endpoint count represent?

The primary outcome is a count of participants who had viral shedding at Day 10. The endpoint description says the assessment used self-collected nasal swab RT-PCR data and a transformation using a referenced standard curve. The arm summary gives a count, not a participant-level series of viral measurements or a treatment-effect estimate. The count is 1 in the camostat arm, whose reported enrollment is 2. The placebo arm has no enrolled participants, so it has no observed endpoint count available for comparison.

General statistical context: a binary outcome records whether a defined event or state occurred for each participant. A count summarizes how many participants met that definition. To compare risks or event frequencies between groups, both groups need outcome data and denominators. A zero-enrollment arm is not the same as an arm in which participants were observed and none had the endpoint. It gives no information about the outcome frequency that would have occurred under placebo.

Why is there no treatment-effect estimate?

A comparative analysis would ordinarily summarize how outcomes differed between the randomized groups, with uncertainty reflecting the amount and variability of the data. Here, the registry record contains no placebo participants and no analysis. It therefore does not provide an estimated between-arm effect, a confidence interval, or a p-value for the primary endpoint. The record does not report a statistical model or test used for this endpoint. These details are not reported in the registry record.

General statistical context: a confidence interval describes a range of effect estimates compatible with the observed data under the method’s assumptions. Its width conveys precision, not the probability that a treatment works. A p-value, when used, describes how unusual data would be under a specified null model and assumptions; it is not a measure of clinical importance. Neither quantity can be reconstructed as a meaningful treatment comparison without observed comparator data and a defined analysis.

What do the design labels establish?

Randomized allocation and double masking are recorded design characteristics. In general, randomization is intended to reduce systematic differences between groups at the point of allocation, while masking is intended to limit influences from knowledge of assignment. Those general purposes do not establish that allocation was implemented as intended in this sub-protocol, nor do they address the lack of placebo enrollment. The detailed randomization and masking procedures are not reported in the registry record.

The overall platform is described as adaptive. General context: an adaptive design can allow planned changes based on accumulating information, but those changes need prespecified rules and appropriate analysis to maintain interpretable results. The specific adaptation rules, decision thresholds, and whether any adaptation affected the camostat sub-protocol are not reported in the registry record. It would be inappropriate to infer them from the general platform description.

How should planning illustrations be read?

The page may include sample-size planning illustrations based on an observed effect. The stated planning assumptions are a two-sided significance level of 0.05, equal allocation between arms, and a normal approximation; the effect to detect is described as a stated fraction of the observed effect. For time-to-event tables, the stated convention is total events; for other tables, it is participants per arm. These are planning assumptions, not reported features of the trial’s own design justification. The registry record does not report a sample-size justification for this sub-protocol.

General statistical context: a planning calculation asks how much information a future or hypothetical study might need to detect a chosen effect under stated assumptions. It does not show the probability that this completed trial found an effect, and it is not observed power. Here, the observed data contain no two-arm contrast from which a comparative effect could be estimated. Consequently, any illustration based on an observed effect should not be read as evidence from the camostat-versus-placebo comparison. No planning illustration can repair the absence of enrolled placebo participants.

The record also does not report interim analyses, analysis populations, handling of missing outcome data, or a detailed statistical analysis plan. Without these details, readers cannot assess whether the posted count reflects an intention-to-treat analysis, a per-protocol analysis, or another defined population. The exact timing and completeness of outcome collection are also not reported in the registry record. The most defensible statistical reading is therefore limited to the recorded arm counts and the absence of a reported comparative analysis.

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("Camostat")
n      <- c(2)
events <- c(1)
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  Camostat  2  1  50.0  1.3  98.7  9.5  90.5  9.4  90.6

11. Multiplicity, Missing Data and Analysis Populations

The platform description includes viral and clinical domains, and the record lists 8 secondary outcomes. These include several time-to-event outcomes and indicators for clinical events, antibodies, and negative RT-PCR tests. The record reports 0 analyses, so it does not present inferential results across these outcomes. A multiplicity adjustment or procedure for prioritizing tests is not reported in the registry record.

General statistical context: when a study tests multiple outcomes or makes multiple comparisons, the chance of at least one apparently notable result can increase unless the analysis plan addresses multiplicity. A prespecified hierarchy, adjustment, or other strategy can help clarify how results should be interpreted. The presence or details of such a strategy for this sub-protocol are not reported in the registry record; no approach should be assumed.

The placebo arm had 0 enrolled participants, while the camostat arm had 2. This is not simply a small amount of missing placebo outcome data: there is no enrolled placebo group to contribute an observed outcome denominator. The reason for the enrollment pattern is not reported in the registry record. The record does not report whether any enrolled participants lacked a Day 10 measurement, how missing outcome observations were handled, or whether any sensitivity analysis was planned or conducted.

Analysis populations, such as intention-to-treat or per-protocol, are not reported in the registry record. Nor are participant-level outcome data or a detailed statistical analysis plan. These omissions limit assessment of how enrollment, follow-up, and endpoint availability were handled. With no posted analyses and no comparator enrollment, neither multiplicity procedures nor missing-data methods can be evaluated from the reported results.

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.

The adverse-event summary reports 2 participants at risk for serious adverse events in the camostat group and 0 with serious adverse events. It reports 2 at risk for other adverse events and 0 affected. The reported number of deaths is 0. In the matching-placebo group, the number at risk is 0 for both serious and other adverse events, with 0 affected and 0 deaths. Because no participants were enrolled in that arm, its zeros do not represent observed evidence of no events among treated placebo participants.

General statistical context: safety counts need to be interpreted alongside the number exposed, the duration and completeness of observation, and how events were defined and collected. Here, the camostat safety summary covers 2 participants, so it provides only a limited description of those participants. It cannot precisely characterize less common events or establish comparative safety against placebo. The registry record does not report detailed event terms among serious events, and the list of top serious-event terms is empty.

The figures are counts in the posted record, not a basis for concluding that a treatment is safe or unsafe. The reason the study ended and the extent of safety follow-up are not reported in the registry record. The placebo arm’s lack of enrollment also means there is no observed safety comparison for that arm.

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

The result does mean that the registry record reports 2 participants in the camostat arm and records viral shedding at Day 10 for 1 of them. It also means that no participants were enrolled in the matching-placebo arm, and that the registry record reports 0 analyses. Those details describe what is posted for this sub-protocol.

The result does not establish a difference between camostat and placebo. With no placebo participants, there is no observed comparator outcome from which to estimate a treatment effect. The record does not provide a confidence interval, p-value, or other measure of uncertainty for a two-arm contrast. It therefore cannot show how precisely a comparative effect is known, or whether any apparent difference is compatible with chance variation.

General statistical context: a randomized design is intended to make groups comparable, but a design label does not generate evidence for a group that has no enrolled participants. Likewise, a count within one arm is not an estimate of what would have happened under the alternative assignment. The small camostat group also means the reported outcome is strongly dependent on the experience of the few enrolled participants; it should not be treated as a stable estimate for a broader population.

The primary endpoint concerns viral shedding measured from nasal swab RT-PCR data. It is not, by itself, a report of clinical recovery or of a patient-centered benefit. Although the registry lists clinical and other secondary outcomes, it reports 0 analyses. The posted record therefore cannot substantiate conclusions about those outcomes either.

Finally, the termination status does not explain why the study stopped, and the empty placebo arm does not explain why it failed to enroll. Those reasons are not reported in the registry record. The careful interpretation is limited: a small set of camostat-arm endpoint and safety counts is posted, but the trial record does not provide a comparative efficacy or safety analysis.

14. Why This Trial Matters Statistically

This record illustrates the difference between a planned randomized comparison and an interpretable comparative result. The design is described as randomized, double-masked, parallel, and placebo-controlled, but the posted enrollment consists of 2 participants in the camostat arm and 0 in the placebo arm. A trial’s design labels are important, yet readers must also inspect who was actually enrolled and what outcomes were analyzed.

Statistically, the absence of a comparator makes the central contrast unavailable. The Day 10 count can be described within the camostat arm, but cannot answer how that count compares with placebo. This distinction helps prevent a within-group observation from being mistaken for a treatment effect. It also clarifies why uncertainty and analysis methods matter: neither a comparative estimate nor its precision is reported.

The platform setting adds another useful lesson. The overall study description covers viral and clinical domains, while each investigational treatment is addressed in a separate sub-protocol. A platform’s broad aims do not mean every sub-protocol has a complete result for every domain. In this record, the primary endpoint is viral shedding, secondary outcomes are listed, and no analyses are reported.

Finally, planning calculations and descriptive safety counts answer different questions from a treatment comparison. Planning illustrations are hypothetical and depend on assumptions; they are not observed evidence. Safety counts among 2 camostat participants describe only that small group, and the empty placebo arm supplies no safety contrast. Reading these elements separately is essential to a transparent account of what the registry record can and cannot show.

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 most consequential limitation is that the matching-placebo arm enrolled 0 participants. This prevents a treatment-versus-placebo estimate for the primary endpoint and leaves no observed comparator for safety outcomes. The camostat arm contains 2 participants, so its counts are highly limited and cannot support precise generalization.

The registry record reports 0 analyses, although it lists 8 secondary outcomes. It does not post comparative results, uncertainty estimates, or inferential tests for the primary or secondary outcomes. The reason the study was terminated and the reason for the empty placebo arm are not reported in the registry record; attributing either to a particular cause would go beyond the available information.

Important analysis details are not reported in the registry record, including the statistical analysis plan, analysis populations, handling of missing outcome data, interim analyses, and detailed methods for randomization and masking. The sample-size justification is not reported in the registry record. The record also does not provide participant-level endpoint information or detailed follow-up completeness.

The primary endpoint is a virologic count at Day 10, not a direct measure of clinical recovery. Although the record lists clinical secondary outcomes, it provides no analyses for them. The safety summary is based on only the enrolled camostat participants; zero counts in the unpopulated placebo arm must not be interpreted as observed safety follow-up. Together, these limits mean the posted record supports only a narrow description of enrollment and recorded counts, not a comparative conclusion.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: COVID-19 Outpatient Pragmatic Platform Study (COPPS) - Camostat Sub-Protocol — NCT04662073.
• Registry record last updated 2023-06-28; status last verified 2023-06.
• Results first posted 2022-12-13.
• 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 COVID-19 Outpatient Pragmatic Platform Study camostat sub-protocol is listed as a randomized, double-masked, parallel Phase 2 study, sponsored by Stanford University. The record gives a start date of 2021-04-23, a primary completion date of 2021-06-08, and a status of terminated.

Enrollment is 2: 2 participants in the camostat arm and 0 in the matching-placebo arm. Both assigned treatments were described as lasting 10 days. The primary endpoint is the number of participants with viral shedding at Day 10; the camostat arm reports 1 participant with this outcome. The record lists 8 secondary outcomes but reports 0 analyses.

The record does not provide a comparative estimate, uncertainty interval, or analysis of the primary outcome. The reason for termination, the reason for the empty placebo arm, and detailed statistical methods are not reported in the registry record. The posted results are therefore descriptive and do not establish a camostat-versus-placebo effect.