M7824 in People With Recurrent Respiratory Papillomatosis: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for M7824 in People With Recurrent Respiratory Papillomatosis (NCT03707587), a na phase 2 study. The primary outcome is Proportion of Participants With a Complete Response.

2. Clinical Question

The study concerns RRP, a condition the registry describes as associated with a virus infection. Its stated objective was to assess M7824 in people with RRP. The intervention description explains that M7824 interferes with PD-L1 activity; that background rationale is not evidence of an observed clinical effect.

Complete response was assessed by flexible endoscopy, with or without imaging studies, before treatment and at 6 and 12 weeks after starting treatment. The endpoint definition requires no evidence of papillomas on the listed physical or endoscopic examinations and, if lesions were assessed by imaging, absence of disease by imaging. The registry names RECIST as the response criteria.

The clinical question is therefore about the proportion meeting a defined response threshold at the specified assessment times in a treated group. It is not a randomized estimate of a difference between M7824 and another treatment. Because the registry record does not state the complete-response result, it does not permit an estimate of how often participants met that endpoint.

3. Trial Design

This was a phase II, single-group study of M7824 in people with recurrent respiratory papillomatosis. The registry lists enrollment of 9 and records the trial as completed. It names the National Cancer Institute (NCI) as sponsor. The recorded start date is 2018-12-19, and the primary completion date is 2019-10-29.

The study had no separate control arm: allocation is recorded as NA, and the model is single group. Masking is recorded as none. The registry also distinguishes Cohort 1, checkpoint inhibitor naive patients, from Cohort 2, patients refractory to checkpoint inhibition. Those cohort labels describe participant groups; they do not create a randomized or like-for-like control comparison.

The intervention was M7824, described as a 1200 mg intravenous dose on day 1 of a 14 day cycle, every other week, for up to 12 weeks total treatment. The arm description gives a maximum of 6 cycles. Screening and study procedures described in the registry included medical history, physical examination, blood and pregnancy tests, and clinic endoscopy. Some participants were also to have a chest scan. At the start of the study, the description includes sedated endoscopy with biopsies, blood tests, apheresis, and a voice questionnaire. Procedures were to be repeated during the study.

The primary outcome was the proportion of participants with a complete response. The registry specifies assessment before treatment and at 6 and 12 weeks after starting treatment. Named secondary outcomes include the number of participants with a partial response, the number with grade 3 or higher adverse events, and the number with serious and non-serious adverse events assessed using CTCAE v5.0.

A single-group design can describe outcomes observed among participants receiving the intervention, but it cannot by itself separate treatment effects from changes that might occur over time or other influences. The registry record does not report the protocol’s rationale for this design, its sample-size justification, or a statistical analysis plan.

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:

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 Proportion of Participants With a Complete Response, measured over Response was assessed by flexible endoscopy with or without imaging studies before treatment and 6 and 12 weeks after starting treatment..

The primary endpoint is the proportion of participants with a complete response. A proportion endpoint represents whether each participant meets a defined outcome and then describes the share of the evaluated group who meet it. Here, complete response is defined using RECIST and the specified clinical examinations; when lesions are assessed by imaging, absence of disease by imaging is also required.

The definition draws on physical examination and clinic-based flexible nasopharyngolaryngoscopy or tracheoscopy, or examination under anesthesia with endoscopy and biopsies. The registry says response was assessed by flexible endoscopy with or without imaging studies before treatment and at 6 and 12 weeks after starting treatment. Thus, the endpoint is tied to both a stated clinical definition and scheduled assessments rather than to an unspecified impression of improvement.

A complete-response endpoint is useful for describing whether the defined disease findings are absent at assessment. It is distinct from partial response, which is listed separately as a secondary outcome. The endpoint definition alone does not establish how many participants achieved complete response, whether all participants were assessed, or how missing assessments were handled.

The registry record does not report the number or proportion with complete response. As a result, the endpoint can be explained but its observed value and precision cannot be interpreted from the registry record. The record also does not report a confidence interval or inferential analysis for this primary outcome.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

Statistical interpretation begins with identifying what the endpoint measures, how participants were grouped, and what comparison the design can support. In this study, the primary measure is a proportion: participants are classified according to whether they meet the complete-response definition. The design is recorded as single group, with no masking and no separate control group. Those features set limits on what a statistical result could establish even if an outcome estimate were available.

What does a proportion measure?

A proportion is a summary of how many people in an evaluated group met a stated condition, relative to the group being evaluated. For a clinical endpoint, interpretation depends on the exact outcome definition, the denominator used, and whether participants with missing assessments are included, excluded, or handled another way. The registry record states the complete-response definition and assessment times, but does not report the observed response count, denominator for the primary analysis, or missing-data approach. The result cannot therefore be reconstructed from the endpoint description.

Complete response is not simply a general label for feeling better. The registry describes absence of papillomas on specified physical or endoscopic examinations and absence of disease by imaging when lesions are assessed by imaging. The use of defined criteria can improve consistency in how an outcome is classified, but interpretation still depends on how the criteria were applied and how assessments were recorded. Details of adjudication or assessor procedures are not reported in the registry record.

What can a single-group study estimate?

A single-group study can describe outcomes observed after participants receive the study intervention. It does not directly estimate a treatment-versus-control contrast because there is no separate control group in this design. A change over time or a response in participants cannot, on its own, determine what would have happened without the intervention. This is why a single-group response proportion should be read as a description of the observed group, not as a causal comparison.

The registry separates participants into checkpoint-inhibitor-naive and checkpoint-inhibitor-refractory cohorts. These labels could matter when describing who was studied, but the record does not describe random assignment between those cohorts. Nor does it provide a cohort-specific primary response result. A comparison between cohorts would require careful attention to their different participant characteristics and treatment histories; the registry record does not report an analysis addressing such a comparison.

How should uncertainty be understood?

A confidence interval is a statistical range used to express uncertainty around an estimate under a specified analysis. In general, an interval gives readers more information than a point estimate alone: it indicates which values are reasonably compatible with the data and the method used. Its width depends on factors including the amount of information in the data and the variability of the outcome. A confidence interval is not reported for the primary endpoint in this registry record, and the response estimate itself is not reported. No numerical interval or claim about precision can therefore be made.

A p-value, when reported, summarizes how compatible data are with a specified statistical model or null hypothesis. It does not measure the probability that a treatment works, and it does not describe the size or clinical importance of an effect. No primary endpoint p-value or inferential analysis is reported. The registry’s lack of a p-value should not be replaced by an inferred test or by a claim that a result was statistically significant or nonsignificant.

What do the planning assumptions mean?

The stated sample-size assumptions describe planning illustrations based on an observed effect, a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. The effect to detect is described as a fraction of the observed effect. In general, a planning calculation asks how much information might be needed to detect a chosen effect under specified assumptions. It does not show that a study actually had a particular probability of detecting an effect after the data were collected.

These assumptions do not match the recorded study structure of a single group with no randomized comparator. Any resulting sample-size illustrations should therefore be understood as hypothetical planning scenarios, not as the trial’s observed power or as analyses of its enrolled participants. The registry record does not report a sample-size justification for the actual design, nor does it state whether the study had interim analyses or a prespecified statistical plan. Those details are not reported in the registry record.

How should safety counts be interpreted?

Safety counts summarize the number of participants recorded as affected within the listed cohort. The denominator matters: the same count can convey different information in differently sized groups. In this study the cohort sizes are small, so each participant’s status has substantial influence on a descriptive count. Such counts can identify events recorded during the study, but they do not establish comparative risk without an appropriate comparison and analysis.

The serious-event and other-event counts are reported separately for the checkpoint-inhibitor-naive and refractory cohorts. The record also lists serious adverse-event terms with percentages, but does not give their denominators or cohort mapping. Statistical interpretation should preserve those distinctions rather than combine the term percentages with the cohort counts. The registry does not report event-specific follow-up time, exposure-adjusted rates, or an analysis of attribution, so those quantities should not be inferred.

Overall, the methods needed to interpret a complete-response estimate—an observed value, a defined analysis population, and uncertainty information—are not available in the registry record. The available design information and safety counts support a limited descriptive reading, not an efficacy comparison or a formal assessment of precision.

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("Cohort 1 - Checkpoint Inhibitor Naive Patients", "Cohort 2 - Patients Refractory to Checkpoint Inhib")
n      <- c(7, 2)
events <- c(0, 0)
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  Cohort 1 - Checkpoint Inhibitor Naive Patients  7  0  0.0  0.0  41.0  0.0  35.4  0.3  36.9
ARM  Cohort 2 - Patients Refractory to Checkpoint Inhib  2  0  0.0  0.0  84.2  0.0  65.8  0.8  70.8

11. Multiplicity, Missing Data and Analysis Populations

The registry names complete response as the primary outcome and lists partial response and adverse-event outcomes as secondary measures. Multiple outcomes can raise a multiplicity question: when several hypotheses are tested, the chance of at least one apparently notable result can increase unless the analysis plan addresses that issue. The registry record does not report a multiplicity adjustment, a hierarchy among secondary outcomes, or which outcomes were intended to support confirmatory conclusions. It is therefore not possible to assess how multiplicity was handled.

Missing outcome data can affect a proportion if some participants do not have an evaluable assessment. The registry specifies response assessments before treatment and at 6 and 12 weeks after starting treatment, but does not report whether every participant completed each assessment. It also does not describe how missing endoscopies, imaging, or other assessments were handled, or whether the primary endpoint used a particular analysis population. These details are not reported in the registry record.

The record does not identify an intention-to-treat population, a per-protocol population, or another defined analysis set. It does not report exclusions from analysis or reasons for missing data. Without those details, readers cannot determine which participants would contribute to an endpoint estimate or whether the analyzed group differs from the enrolled group.

The record reports no analysis results for the primary response outcome and no analysis plan. The handling of multiplicity, missing data, and analysis populations is therefore not reported in the registry record. No assumptions about those procedures should be substituted for the absent information.

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 serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: laryngeal obstruction (50.0%), sudden death nos (50.0%), lung infection (14.3%).

The safety entries are organized by cohort. In Cohort 1, the registry records 7 participants at risk for serious adverse events, with 3 affected; it records 7 at risk for other adverse events, with 7 affected, and 0 deaths. In Cohort 2, it records 2 at risk for serious adverse events, with 2 affected; 2 at risk for other adverse events, with 2 affected, and 1 death. These are counts within the listed cohorts, not comparative estimates.

The registry also lists serious adverse-event terms and percentages: laryngeal obstruction, 50.0%; sudden death NOS, 50.0%; and lung infection, 14.3%. The record does not specify the denominator for these percentages or identify the cohort associated with each term. They should be read as reported event-term summaries, not as a basis for calculating or comparing cohort-specific risks.

Serious events, other adverse events, and deaths are distinct summaries. The record does not report enough detail to establish whether an event was caused by M7824, how long each participant was observed for safety, or the clinical circumstances of the deaths. The counts describe what the registry records; they do not establish causation.

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

The registry record establishes that a phase II, single-group study of M7824 in people with recurrent respiratory papillomatosis was completed and that complete response was its primary endpoint. It also specifies the endpoint definition and assessment schedule. Those details explain what the study set out to measure, but the registry record does not report the observed complete-response result. The main efficacy outcome therefore cannot be quantified or assessed for precision from this record.

The safety entries provide descriptive counts in the two named cohorts, along with a list of serious adverse-event terms. They should be interpreted within the small groups in which they were recorded. The counts do not by themselves show whether M7824 caused an event, and the study design does not provide a randomized control group for estimating comparative safety or efficacy.

A study’s rationale and its outcome are different kinds of information. The registry background describes why interference with PD-L1 activity was considered relevant to a condition associated with viral infection. That biological rationale does not substitute for a reported clinical endpoint. Likewise, the stated objective does not establish that the objective was met.

The absence of a posted primary outcome result is a limitation of what can be concluded from the registry record, not evidence for a particular response rate. The record also does not report a confidence interval, p-value, missing-data approach, or defined analysis population for the primary endpoint. Without those details, neither the size nor the statistical uncertainty of a complete-response estimate can be described.

Accordingly, the registry record supports a description of the study design, endpoint definition, and recorded safety counts. It does not establish an efficacy comparison, a causal treatment effect, or a precise estimate of complete response. Those claims would require results and analysis details that are not reported in the registry record.

14. Why This Trial Matters Statistically

This trial is statistically notable because its primary clinical question is expressed as a clearly defined response proportion, while the registry record does not report that primary result. The distinction between a prespecified measure and an observed estimate matters: knowing what an endpoint means is not the same as knowing its value. A reader can understand the response criteria and assessment schedule, but cannot infer how many participants met the criteria.

The single-group design also makes the interpretation especially dependent on careful wording. A response proportion in a treated group is descriptive. Without a control group, the design does not directly quantify how outcomes differ from an alternative condition, and it cannot isolate a treatment effect from other influences. The cohort labels do not change that basic limitation because the registry does not describe randomized assignment between the cohorts.

The safety figures illustrate why denominators and group context matter. Counts are reported separately for checkpoint-inhibitor-naive and refractory participants, and the listed cohort sizes are small. A count in such a group is useful as a record of observed events, but it should not be mistaken for a stable comparative risk estimate. The serious-event term percentages also require caution because their denominators and cohort mapping are not reported.

More broadly, the record distinguishes the study’s biological rationale, its endpoint definition, and its observed results. Statistical interpretation depends on keeping those elements separate. Rationale does not demonstrate an effect; a defined endpoint does not reveal its value; and adverse-event counts do not establish causation. The missing primary result and analysis details sharply limit what can be concluded from this registry entry.

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 central limitation for interpreting efficacy is that the registry record does not report the primary complete-response result. Although the endpoint definition and assessment schedule are described, there is no observed proportion, response count, confidence interval, or p-value to evaluate. The primary clinical question therefore remains unanswered by the posted results.

The design is single group, with no separate control and no masking. It cannot provide a randomized comparison or distinguish outcomes associated with treatment from changes due to other factors. The checkpoint-inhibitor-naive and refractory cohort labels describe different groups, but the record does not report a randomized comparison or cohort-specific primary response estimates.

The overall enrollment is 9, and the cohort safety counts are reported in small groups. Those counts are descriptive and can be sensitive to each participant’s event status. The serious-event percentages are listed without denominators or cohort attribution, limiting their interpretation. The registry does not report safety follow-up duration, exposure-adjusted rates, event attribution, or detailed circumstances for the recorded death.

Important analytic details are also absent. The registry record does not report a statistical analysis plan, sample-size justification for the actual design, interim-analysis procedures, analysis populations, or methods for missing assessments. It does not state whether each scheduled response assessment was completed or how incomplete assessments were handled. These omissions prevent evaluation of potential selection, missing-data, and analysis-related limitations beyond those evident from the recorded design.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: M7824 in People With Recurrent Respiratory Papillomatosis — NCT03707587.
• Registry record last updated 2022-09-29; status last verified 2022-09.
• Results first posted 2020-10-14.
• 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

NCT03707587 is a completed phase II, single-group study sponsored by the National Cancer Institute (NCI), evaluating M7824 in people with recurrent respiratory papillomatosis. The registry records enrollment of 9, no masking, and no separate control group. Treatment was described as 1200 mg intravenously every other week for up to 12 weeks.

The primary outcome was the proportion of participants with complete response, assessed by endoscopy with or without imaging before treatment and at 6 and 12 weeks after starting treatment. The registry defines complete response using RECIST and specified clinical examinations, with absence of disease by imaging when lesions were assessed by imaging. The primary result is not reported in the registry record.

Safety counts are reported for checkpoint-inhibitor-naive and checkpoint-inhibitor-refractory cohorts. The registry record does not report a primary efficacy analysis, confidence interval, p-value, analysis population, or missing-data method.