Safety, Pharmacokinetics, Pharmacodynamics, and Preliminary Efficacy Trial of BNT411: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Safety, Pharmacokinetics, Pharmacodynamics, and Preliminary Efficacy Trial of BNT411 (NCT04101357), a non-randomized phase 1, phase 2 study. The primary outcome is Number of Participants With Dose Limiting Toxicities (DLTs).

2. Clinical Question

The study was a Phase 1/2a, first-in-human, open-label trial. Its two dose-escalation parts evaluated BNT411 alone and with the three-drug combination. An expansion part was planned to assess the treatment settings further, but the sponsor decided not to continue with that part.

The clinical question is therefore descriptive and dose-oriented rather than a comparative effectiveness question. In the absence of randomization and a like-for-like control group, differences between the monotherapy and combination cohorts cannot be interpreted as treatment effects. The populations also differ by the cancer setting described for each part, so the cohorts do not establish a direct comparison between treatment strategies.

The registry description states that the trial aimed to establish a safe dose and to assess safety, pharmacokinetics, pharmacodynamics, and preliminary efficacy. However, it does not report primary endpoint counts, efficacy estimates, or analyses of the outcome measures. The posted record therefore supports a review of the design and the recorded safety summaries, but not a conclusion about the primary endpoint or preliminary efficacy.

3. Trial Design

This was a Phase 1/2a, first-in-human, open-label, non-randomized, sequential trial of BNT411. The registry record lists BioNTech SE as sponsor, an enrollment of 54, and a status of terminated. The recorded start date is 2020-06-19 and the primary completion date is 2024-01-19.

Part 1A evaluated BNT411 monotherapy through dose escalation in patients with solid tumors. Part 1B evaluated BNT411 with atezolizumab, carboplatin, and etoposide in patients with chemotherapy-naïve extensive-stage small cell lung cancer. The posted safety table identifies the monotherapy dose levels as 0.05 mcg/kg, 0.15 mcg/kg, 0.45 mcg/kg, 1.2 mcg/kg, 2.4 mcg/kg, 4.8 mcg/kg, 6.0 mcg/kg, 7.2 mcg/kg, and 9.6 mcg/kg. The combination dose levels shown are 1.2 mcg/kg and 2.4 mcg/kg.

Part 2 was described as expansion cohorts for BNT411 alone or in combination with the other therapies. The sponsor decided not to continue with this part of the trial. The registry record does not report why the decision was made, so the termination status should not be taken as evidence of a particular reason for stopping.

There was no masking and no random allocation. The sequential model is consistent with the dose-escalation structure, but the registry record does not report the specific dose-escalation algorithm, cohort decision rules, or other protocol details. The planned study objectives included safety, pharmacokinetics, pharmacodynamics, and preliminary efficacy. Secondary outcomes listed pharmacokinetic measures including area under the concentration time curve, clearance, volume of distribution, maximum plasma concentration, time to maximum concentration, trough concentration, and terminal elimination half-life.

The registry record lists 12 outcome measures and 0 analyses. It does not report the participant flow by study part, the number who completed each part, or the number who contributed to each outcome. The enrollment figure alone does not establish how many participants were evaluable for the primary endpoint.

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: The trial was planned with three parts: Part 1A, Part 1B, and Part 2. Part 2, which was planned to consist of expansion cohorts in solid tumors was not conducted as the trial was terminated prematurely.

Only the first 6 of 11 groups are shown.

Overall Study

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: Analysis was performed on DLT evaluable set that included participants who received at least one dose of BNT411 and have completed the DLT evaluation period and meet the minimum exposure criterion or have experienced a DLT during the DLT evaluation period (Cycle 1).

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: Analysis was performed on safety set that included all participants who received at least one dose of BNT411.

Only the first 6 of 12 groups are shown.

6. Primary Endpoint

The registry lists the primary outcome as Number of Participants With Dose Limiting Toxicities (DLTs), measured over Cycle 1 (21 Days).

The primary endpoint was the number of participants with dose-limiting toxicities (DLTs) during Cycle 1 (21 Days). It was a count of participants meeting the DLT definition, rather than a measure of the total number of adverse events. The analysis population was the DLT-evaluable set: participants who received at least one dose of BNT411 and completed the DLT evaluation period while meeting the minimum exposure criterion, or who experienced a DLT during that period.

The registry definition included non-immune-related adverse events and immune-related adverse events. An event qualified if it was Grade 3 and did not resolve to Grade 1 or lower within a week, or if it was Grade 4. Severity grading was described using National Cancer Institute Common Terminology Criteria for Adverse Events, version 5.0: Grade 1 was mild, Grade 2 moderate, Grade 3 severe, Grade 4 life-threatening consequences, and Grade 5 death related to an adverse event.

In general, a DLT endpoint is used in early-phase dose evaluation because it focuses attention on serious toxicities occurring in a defined observation period. A count of affected participants can help describe how many evaluable participants met the study’s toxicity threshold at a dose. It does not, by itself, summarize all harms, establish causation, or measure efficacy.

The registry record does not report the primary endpoint count or its results by dose level. As a result, readers cannot use the posted primary endpoint to identify which doses had observed DLTs or to assess the precision of any dose-specific estimate.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The trial’s statistical interpretation begins with its structure. It was open-label, non-randomized, and sequential, with monotherapy and combination dose-escalation parts. In general, sequential dose escalation evaluates doses in an ordered process, but the precise algorithm and rules for advancing or pausing doses are not reported in the registry record. It would therefore be inappropriate to infer a particular escalation design from the study description alone.

What does a count endpoint represent?

The primary outcome is a count of participants who met the DLT definition during Cycle 1 (21 Days). It is not a count of all events, and it is not a rate per unit of follow-up. The event definition combines toxicity grade with a resolution condition for Grade 3 events. This makes the outcome dependent on both event severity and the specified observation and resolution criteria.

In general, a binary participant outcome records whether each participant did or did not meet a defined condition. A count summarizes how many participants met that condition in a group. To interpret a count as a proportion or estimate of risk, the number of evaluable participants in the same group is also needed. The posted primary results do not give those DLT counts or the related analysis, so no such interpretation is available.

Why does the analysis population matter?

The registry defines a DLT-evaluable set rather than simply describing all enrolled participants as the primary analysis population. Inclusion required receipt of at least one dose of BNT411 and completion of the DLT evaluation period while meeting a minimum exposure criterion, unless a DLT occurred during that period. Such criteria determine who contributes to the endpoint denominator and can affect the interpretation of a safety summary.

The minimum exposure criterion itself and the number of participants meeting each eligibility condition are not reported in the registry record. The posted enrollment of 54 should not be treated as the DLT-evaluable population. The number evaluated at each dose and the handling of participants who did not complete the observation period are also not reported.

What can dose-group summaries show?

The safety table organizes participants by dose level and study part. In general, descriptive summaries are useful for showing the observed events within each cohort, particularly in early-phase studies where dose-specific safety is a central objective. But these summaries do not create a controlled comparison. Dose groups may differ in dose, treatment combination, disease setting, and the participants represented. This trial was not randomized, and the registry itself warns against treating the arms as like-for-like controls.

For that reason, differences in raw counts across groups should not be interpreted as evidence that one dose or regimen caused more or fewer events than another. A valid comparison would require a defined analysis and appropriate consideration of the group structure. Such an analysis is not reported in the registry record.

How should uncertainty be considered?

In general, an estimate is more informative when accompanied by a measure of uncertainty, such as a confidence interval. A confidence interval describes the uncertainty around an estimate under the assumptions of a statistical method; it does not remove limitations in the study design or establish causation. No primary endpoint estimate or confidence interval is reported. Consequently, the precision of the DLT findings cannot be judged from the registry record.

Counts from small cohorts can be particularly difficult to interpret because a single participant’s outcome can meaningfully change the descriptive picture. That general caution is relevant to dose-escalation summaries, but the record does not provide an inferential analysis that would quantify uncertainty for these cohorts. No p-values, confidence intervals, or model-based estimates for the primary endpoint are reported.

What is not reported about the statistical plan?

The registry record does not report a sample-size justification, the target precision for safety estimates, a planned statistical model, or interim analysis procedures. It also does not report how multiple outcomes were handled statistically. The presence of multiple objectives and outcome measures does not tell readers whether any formal multiplicity adjustment was planned or used.

General statistical practice distinguishes a study’s planned analyses from analyses that can be reconstructed from posted summaries. Here, the record lists 12 outcome measures but 0 analyses. There is no posted primary endpoint analysis to explain or reproduce, and the stated secondary pharmacokinetic outcomes are not accompanied by results in this record. These omissions limit the statistical conclusions that can be drawn, without implying that any specific analysis was or was not performed outside the registry record.

Finally, the study’s open-label and non-randomized structure is important to interpretation. Open-label means treatment assignment was not masked. In general, lack of masking can affect outcome assessment or reporting, though the extent depends on the outcome and conduct of the study. For a defined toxicity endpoint, standardized grading criteria help specify classification, but they do not replace details on assessment procedures, independent review, or analysis. Those details are not reported in the registry record.

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 1A: BNT411 Monotherapy: DL1: 0.05 mcg/kg", "Part 1A: BNT411 Monotherapy: DL2: 0.15 mcg/kg", "Part 1A: BNT411 Monotherapy: DL3: 0.45 mcg/kg", "Part 1A: BNT411 Monotherapy: DL4: 1.2 mcg/kg", "Part 1A: BNT411 Monotherapy: DL5: 2.4 mcg/kg", "Part 1A: BNT411 Monotherapy: DL6: 4.8 mcg/kg")
n      <- c(2, 1, 1, 3, 3, 10)
events <- c(0, 0, 0, 0, 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  Part 1A: BNT411 Monotherapy: DL1: 0.05 mcg/kg  2  0  0.0  0.0  84.2  0.0  65.8  0.8  70.8
ARM  Part 1A: BNT411 Monotherapy: DL2: 0.15 mcg/kg  1  0  0.0  0.0  97.5  0.0  79.3  1.3  84.2
ARM  Part 1A: BNT411 Monotherapy: DL3: 0.45 mcg/kg  1  0  0.0  0.0  97.5  0.0  79.3  1.3  84.2
ARM  Part 1A: BNT411 Monotherapy: DL4: 1.2 mcg/kg  3  0  0.0  0.0  70.8  0.0  56.1  0.6  60.2
ARM  Part 1A: BNT411 Monotherapy: DL5: 2.4 mcg/kg  3  0  0.0  0.0  70.8  0.0  56.1  0.6  60.2
ARM  Part 1A: BNT411 Monotherapy: DL6: 4.8 mcg/kg  10  0  0.0  0.0  30.8  0.0  27.8  0.2  28.5

11. Multiplicity, Missing Data and Analysis Populations

The registry record lists multiple study objectives and 12 outcome measures. It identifies a primary DLT endpoint and several secondary pharmacokinetic outcomes, including AUC0-last, CL, Vd, Cmax, Tmax, Ctrough, and T1/2. However, it reports 0 analyses. It therefore does not show how the outcomes were analyzed or whether any formal adjustment for testing multiple outcomes was planned or used.

In general, multiplicity arises when several hypotheses or outcomes are examined: the chance of at least one apparently notable result can increase as the number of analyses grows. A statistical plan may address this through prespecified ordering, adjustment, or other approaches. The registry record does not report such a plan, so readers cannot determine how multiplicity was handled. This absence does not establish that no plan existed outside the registry.

Missing-data methods are also not reported. The primary analysis population is defined as the DLT-evaluable set, with eligibility tied to exposure and completion of the DLT evaluation period, or occurrence of a DLT. The record does not report how many participants were excluded from that set, how incomplete assessments were treated, or how missing pharmacokinetic or other outcome observations were handled.

The posted enrollment of 54 does not resolve these questions. It is not a substitute for outcome-specific denominators or an account of participant flow. The registry record does not report a sample-size justification, interim analysis plan, or statistical analysis plan. As a result, the reader cannot assess whether the planned sample was selected to achieve a particular precision or how incomplete data and multiple outcomes were intended to affect inference.

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: covid-19 (100.0%), acute kidney injury (100.0%), hyponatraemia (66.7%), nausea (50.0%), pain (50.0%).

The safety table presents dose-group summaries, including the number at risk and affected for serious adverse events and other adverse events, as well as reported deaths. These are descriptive figures for the groups listed in the registry record. They should not be read as a randomized comparison: the trial was non-randomized and open-label, and its cohorts differed by study part and treatment regimen.

The table also lists serious adverse-event terms, including COVID-19 and acute kidney injury at 100.0%, and hyponatraemia at 66.7%. Nausea, pain, and hepatic failure are listed at 50.0%. These are the percentages displayed in the registry record; the denominator and calculation basis for the term percentages are not reported in the record. They should therefore be understood as entries in the posted summary, not as directly comparable risks across treatment groups.

Counts of affected participants and deaths do not by themselves establish that BNT411 or another study treatment caused an event. The registry record does not provide the event-level context or causal attribution needed to make that judgment. Nor should the serious-event figures be confused with the primary DLT endpoint, which has its own definition and observation period. The posted DLT results are not reported.

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

The registry record documents a first-in-human Phase 1/2a study of BNT411, with monotherapy and combination dose escalation, and provides a definition for the primary DLT endpoint. It also describes the planned expansion cohorts and notes that the sponsor decided not to continue with that part. The record’s status is terminated.

What the posted record does not establish is the primary endpoint result. It gives no DLT counts by dose, no estimate of the frequency of DLTs, and no confidence interval or statistical analysis for that endpoint. Although the safety table contains descriptive counts for serious and other adverse events and deaths, those summaries do not substitute for the DLT outcome or a comparative analysis.

The record also does not report analyses of pharmacokinetic, pharmacodynamic, or preliminary efficacy outcomes. The presence of these objectives and named outcomes shows the scope of the trial, not the results. In particular, the registry record cannot support a conclusion about efficacy, comparative benefit, or which dose should be selected.

In general, an early-phase dose-escalation study is intended to characterize safety and inform further evaluation, rather than to provide a randomized estimate of treatment effect. This study had no randomized control arm, and the registry warns that its arms are not a like-for-like comparison. Differences across the displayed cohorts could reflect their different doses, combination therapies, or study populations, among other features; the record does not provide an analysis separating these influences.

The most defensible conclusion is narrow: the record describes how the trial was structured and what outcomes it planned to assess, and posts some safety summaries. It does not report enough primary endpoint or analysis information to determine the observed DLT findings or draw a treatment-effect conclusion. Termination of the trial and the decision not to continue the expansion part are recorded details, but the reason for those decisions is not reported.

14. Why This Trial Matters Statistically

This trial illustrates why early-phase results need to be read in relation to their design and reporting. The primary endpoint is a defined DLT count during Cycle 1 (21 Days), and the trial evaluates BNT411 across escalating doses, both alone and alongside atezolizumab, carboplatin, and etoposide. Those features make cohort-specific safety description central to the study’s stated purpose.

At the same time, the registry record shows the limits of interpreting early-phase cohorts as if they were comparative arms. Allocation was non-randomized, there was no masking, and the monotherapy and combination parts involved different treatment settings. The registry explicitly cautions that the arms are not a like-for-like control comparison. This is a useful reminder that numerical differences between cohorts are not automatically treatment effects.

The record also demonstrates the distinction between an endpoint definition and an endpoint result. It defines which toxicities counted as DLTs and identifies the analysis population, but does not post the DLT counts or analyses. Without those results, readers cannot assess dose-specific findings or their precision. A registry entry can therefore document trial intent and methods while leaving key outcome questions unresolved.

Finally, the record lists pharmacokinetic outcomes and broader safety and preliminary efficacy objectives, but reports 0 analyses. This makes transparency about outcome reporting especially important: planned measures should not be mistaken for observed findings. The study’s terminated status and discontinued expansion part are relevant context, while the reasons and statistical implications of those decisions are not reported.

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 main trial-specific limitation in interpreting this record is that the primary DLT outcome is defined but its results are not reported. There are no posted DLT counts by dose, no primary endpoint estimate, and no reported uncertainty measure. The record lists 0 analyses, limiting assessment of how the endpoint and other outcomes were handled statistically.

The study was open-label and non-randomized, without a randomized control group. The registry cautions that the arms are not a like-for-like comparison. In addition, monotherapy and combination cohorts represent different treatment settings, and the combination included atezolizumab, carboplatin, and etoposide. The design therefore does not support a direct causal comparison between those parts.

The registry lists enrollment of 54, but does not report the number evaluable for the primary endpoint by dose, participant flow, or the number completing each study part. Although it defines the DLT-evaluable population, it does not give the minimum exposure criterion or explain how incomplete outcome data were handled. A sample-size justification and statistical analysis plan are not reported.

The posted adverse-event summaries are descriptive. The record does not provide event-level context or causal attribution for the serious events and deaths, and it does not state the denominator basis for the listed serious-event term percentages. The reason the sponsor discontinued the expansion part is also not reported. These omissions constrain interpretation of safety and study conduct; they do not establish a particular explanation for the trial’s termination.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Safety, Pharmacokinetics, Pharmacodynamics, and Preliminary Efficacy Trial of BNT411 — NCT04101357.
• Registry record last updated 2025-03-18; status last verified 2025-02.
• Results first posted 2025-03-18.
• Data retrieved from ClinicalTrials.gov on 2026-11-09.
• Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.

19. Record Summary

This registry record describes NCT04101357, a Phase 1/2a, first-in-human, open-label, non-randomized, sequential trial of BNT411. It lists an enrollment of 54 and a status of terminated. The study evaluated BNT411 monotherapy and BNT411 with atezolizumab, carboplatin, and etoposide, with dose escalation followed by planned expansion cohorts. The sponsor decided not to continue with the expansion part.

The primary endpoint was the number of participants with DLTs during Cycle 1 (21 Days), assessed in a defined DLT-evaluable population. The registry record lists 12 outcome measures and 0 analyses. It includes descriptive adverse-event summaries and named pharmacokinetic outcomes, but does not report primary endpoint results, statistical analyses, efficacy findings, or the reason for termination.

Because allocation was non-randomized and the arms were not like-for-like control groups, the posted data do not support comparative treatment conclusions. Interpretation is limited to the study design, endpoint definition, and descriptive information recorded in the registry.