Talimogene Laherparepvec and Panitumumab for the Treatment of Locally Advanced or Metastatic Squamous Cell Carcinoma of the Skin: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Talimogene Laherparepvec and Panitumumab for the Treatment of Locally Advanced or Metastatic Squamous Cell Carcinoma of the Skin (NCT04163952), a na phase 1 study. The primary outcome is Number of Participants With Treatment Related Adverse Events as Assessed by CTCAE v4.0.

2. Clinical Question

This is an early-phase combination-treatment study, not a randomized comparison of the combination against panitumumab alone or another treatment. Its single-group structure can describe events observed among participants receiving the study treatment, but it cannot separate the effects of the individual drugs or establish what would have happened under a comparator treatment. The small enrollment and the absence of reported efficacy analyses also limit what can be concluded about response or disease course. The study rationale describes a possible biological basis for combining the agents; that rationale is not itself evidence of a clinical effect.

3. Trial Design

The registry describes a phase 1, single-group study sponsored by Rutgers, The State University of New Jersey. Enrollment was 5. Allocation is listed as not applicable, and masking is listed as none. The study status is terminated. Its start date is 2020-01-31, and its primary completion date is 2025-03-28. The reason for termination is not reported in the registry record.

The treatment arm is described as talimogene laherparepvec with panitumumab. Participants receive talimogene laherparepvec intramuscularly on day 1, followed by talimogene laherparepvec intramuscularly and panitumumab intravenously over 30-90 minutes on day 22. The schedule is described as repeating every 2 weeks for up to 3 cycles in the absence of disease progression or unacceptable toxicity. The registry does not identify a concurrent comparison arm.

The registered primary outcome is the number of participants with treatment-related adverse events meeting the stated severity threshold. Registered secondary outcomes include best overall response, durable response, duration of response, progression-free survival, overall survival, and tumor mutation or expression measures. The registry lists 16 outcome measures, but the record reports 0 analyses. The posted safety information therefore should not be mistaken for a full report of all registered outcomes.

The registry record does not report the rationale for the enrollment target, a statistical analysis plan, an interim-analysis plan, or details of the study's termination. The record also does not report a comparator-based design or masking procedures. These omissions mean the design can be described from the listed information, but its planning decisions cannot be reconstructed from the registry entry.

4. Participant Flow and Accounting

The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.

Overall Study

5. Baseline Characteristics

The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.

6. Primary Endpoint

The registry lists the primary outcome as Number of Participants With Treatment Related Adverse Events as Assessed by CTCAE v4.0, measured over Up to 30 days.

The primary endpoint is the number of participants who experience treatment-related adverse effects of grade three or higher, assessed using CTCAE v4.0. The registry defines grades 1-4, with 4 being the most severe, and sets the outcome timeframe as up to 30 days. It is an event-count endpoint: it concerns how many participants meet the stated event definition, rather than the number of separate episodes or a measure of symptom change.

Safety outcomes are especially relevant in an early-phase study of a treatment combination because they describe tolerability and potential harms observed during the specified follow-up. A severity threshold can focus attention on higher-grade events, while treatment-related attribution attempts to distinguish events considered related to study treatment from events due to other causes. These are general features of safety endpoints; attribution depends on the study's assessment process.

The registry record does not report the primary endpoint result as defined, including the number meeting the grade-three-or-higher, treatment-related definition. The posted adverse-event figures separately report serious adverse events, other adverse events, and deaths. Seriousness and severity grade are different concepts: an event classified as serious is not automatically a grade-three-or-higher event, and a severity grade does not by itself determine seriousness. The posted serious-event counts therefore cannot substitute for the defined primary endpoint.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What does a single-group design allow?

In a single-group study, participants receive the study treatment and outcomes are described within that group. This can document what happened during treatment and follow-up. It does not provide a concurrent untreated or alternative-treatment group to serve as a benchmark. Differences from another treatment cannot be estimated directly, and changes over time cannot be attributed to the study treatment alone. This is a general design principle; in this study, the registry specifically lists a single-group model and no comparator.

The study rationale mentions comparison with panitumumab alone as a possible motivation for combining treatments. That statement does not create a panitumumab-alone arm. The registry lists allocation as not applicable and masking as none, and its arm description lists the combination regimen. Therefore, interpretation should remain within the treated group and should not imply a comparative treatment effect.

How should event counts be read?

A count of participants affected differs from a count of event episodes. A participant may experience more than one event, while an event term may be reported for a participant already counted under another term. Unless the record gives participant-level detail or clarifies the counting rules, event terms should not be summed to infer how many people experienced an event. The posted figures distinguish participants at risk from participants affected for serious and other adverse events; they do not give a participant-level breakdown of overlap among terms.

Adverse-event seriousness and severity are separate classifications. Seriousness generally concerns consequences or regulatory criteria, while severity describes how intense an event is. This is general statistical and clinical-trial terminology. Here, the primary endpoint specifically requires treatment-related events of grade three or higher under CTCAE v4.0. The separate serious-event count does not reveal how many events met that exact combination of attribution and grade criteria.

What do precision and uncertainty mean?

For an estimated event rate or treatment effect, a confidence interval describes a range of values compatible with the data and the method's assumptions. A narrow interval indicates greater precision than a wide interval. Small samples generally yield limited precision, especially for uncommon outcomes. This is general explanation; the registry record does not report confidence intervals or an estimated treatment effect for the registered efficacy outcomes. No interval should be inferred from the posted counts.

A p-value, when reported, assesses how incompatible observed data are with a specified statistical null model under its assumptions. It is not the probability that a treatment works, and it does not measure clinical importance. The registry record reports 0 analyses, so it provides no reported p-values for the registered outcome analyses. Without a comparator and a stated analysis, there is no basis in this record for a comparative significance claim.

What is over-dispersion, and is it addressed?

For count outcomes, over-dispersion means the observed variability is greater than expected under a chosen count model. If present and ignored, standard errors may be too small and confidence intervals or tests may give an overly confident impression. This is a general consideration for modeling counts, not a finding about this study. The registry record does not report a count model, an over-dispersion assessment, or an analysis plan, so no particular modeling choice can be attributed to the investigators.

How should planning illustrations be understood?

The sample-size material is described as a planning illustration computed from an observed effect, not as the trial's original design. Its stated assumptions include a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation; the effect to detect is expressed as a fraction of the observed effect. These are assumptions for illustration, not evidence that the trial was designed or conducted as a two-arm comparison. They do not describe observed power. The study itself is registered as single-group, and the registry record does not report the original sample-size justification.

Planning calculations ask what sample size would be needed under specified assumptions for a future or hypothetical design. They are not a retrospective measure of how likely the completed study was to detect an effect. In addition, a planning illustration based on an observed effect inherits uncertainty from that effect estimate. With no reported efficacy analysis and no randomized comparison, such an illustration cannot convert this record into comparative evidence. The stated assumptions should be kept separate from the actual study design.

What is not reported?

The registry record does not report a full statistical analysis plan, methods for handling missing outcomes, analysis populations, covariate adjustments, or an interim-analysis plan. It does not describe whether any multiplicity procedure was used for the several registered outcomes. These are not details that can be inferred from the fact that outcomes were registered. General statistical methods can explain why these choices matter, but they cannot establish which choices were made in this study.

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("Treatment (Talimogene Laherparepvec, Panitumumab)")
n      <- c(5)
events <- c(2)
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  Treatment (Talimogene Laherparepvec, Panitumumab)  5  2  40.0  5.3  85.3  11.8  76.9  11.8  77.7

11. Multiplicity, Missing Data and Analysis Populations

The registry lists multiple secondary outcomes, including response measures, duration of response, progression-free survival, overall survival, and tumor-based molecular measures. When several outcomes are tested, the chance of at least one apparently notable result can increase if each is assessed independently. Statistical approaches can address this multiplicity, for example by specifying a primary comparison in advance or adjusting inference across a defined family of tests. This is general explanation, not a description of methods used in this study. A multiplicity strategy is not reported in the registry record.

The record identifies a primary safety endpoint and a set of secondary outcomes, but it does not report a statistical analysis plan or analyses for those outcomes. The status of each registered outcome, including whether it was analyzed, is not detailed in the registry record beyond the listing of 0 analyses. Consequently, readers cannot determine from this entry whether a particular outcome was prespecified for a specific analysis, whether any analyses were exploratory, or how multiple outcomes were handled.

Missing-data methods and analysis populations are also not reported in the registry record. It is therefore not possible to tell how absent assessments, withdrawals, or participants with incomplete follow-up were handled. The record does not state whether the primary endpoint used an intention-to-treat, safety, or other analysis population. Those labels should not be assigned without an explicit definition. The limited posted event counts do not resolve these omissions or indicate whether all registered outcomes were available for every participant.

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 5% reporting threshold.

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: anemia (20.0%), abdominal pain (20.0%).

The registry reports serious adverse events for the treatment group with 5 participants at risk and 2 affected. It reports other adverse events with 5 at risk and 5 affected, and lists 1 death. These are descriptive counts. The record lists anemia and abdominal pain as top serious adverse-event terms, each at 20.0%.

These categories should not be conflated. The primary endpoint concerns treatment-related adverse events of grade three or higher, while the figures above are organized by serious versus other adverse events. Seriousness does not automatically indicate a particular CTCAE grade, and the posted serious-event counts do not establish treatment-relatedness. The registry record does not report whether the death was treatment-related.

Event terms can overlap within participants, so the listed terms should not be added to infer a participant total. The small group and absence of a comparator also limit interpretation: the counts describe events recorded in this study group but do not show whether their frequency differs from another treatment or from the disease course.

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

The record documents a phase 1 study of talimogene laherparepvec with panitumumab in a single group and posts limited adverse-event counts. It also establishes which outcomes were registered, including response, survival, and tumor molecular outcomes. These details are useful for understanding the study's intended scope and the safety events recorded in the registry.

The record does not establish that the combination improves response, progression-free survival, or overall survival. The registry reports 0 analyses, and results for the listed efficacy outcomes are not reported in the registry record. The study has no comparator group, so it cannot estimate how outcomes under the combination differ from outcomes under panitumumab alone or another treatment. The rationale that the combination may work better than panitumumab alone is a study rationale, not a result.

The adverse-event counts also do not establish that treatment caused the events. In particular, the listed death is not identified as treatment-related, and serious adverse events are not interchangeable with the primary endpoint's treatment-related grade-three-or-higher definition. The record does not report the primary endpoint result using that full definition.

These limits do not mean that the treatment had no effect or that no safety events occurred beyond those listed. They mean that the registry entry does not provide the comparative design, outcome analyses, or precision estimates needed to support such conclusions. The study's terminated status is recorded, but the reason for termination is not reported in the registry record. Statistical interpretation should therefore remain descriptive and bounded by the posted information.

14. Why This Trial Matters Statistically

This study is statistically notable because its registered question combines a safety endpoint with a set of efficacy and biological outcomes, while the design is single-group and enrollment is 5. That combination makes it important to distinguish what the study can describe from what would require a comparison. A single-group study can record adverse events and treatment experiences, but it cannot by itself estimate a treatment contrast.

The primary endpoint also illustrates why endpoint definitions matter. The endpoint is not simply any adverse event or any serious adverse event: it specifies treatment-related events at grade three or higher under CTCAE v4.0. The posted serious-event figures use a different classification. Treating them as the primary result would change the question being answered.

The registry lists clinically and biologically distinct secondary outcomes, from response and survival to tumor mutation and expression signatures. Such breadth can be useful for generating questions, but interpretation depends on outcome-specific methods, missing-data handling, and multiplicity procedures. Those details and analyses are not reported in the registry record.

Finally, the sample-size material is explicitly a planning illustration rather than the original study design. Separating planning assumptions from observed evidence prevents an illustrative calculation from being mistaken for observed power or a result from a controlled trial. The record underscores the value of transparent reporting of endpoints, analysis populations, methods, and outcome estimates, particularly when enrollment is small and there is no comparator.

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 study enrolled 5 participants and had no comparator group. As a result, the posted counts are descriptive and cannot support a direct estimate of how event rates or efficacy outcomes differ from another treatment. Small enrollment also limits the precision with which uncommon events or outcomes can be characterized. These constraints apply regardless of whether an event is clinically important.

The primary endpoint is defined as treatment-related adverse events of grade three or higher, but the posted safety figures do not report that endpoint in its defined form. Serious adverse events and other adverse events are reported separately, and the record does not provide enough detail to map these categories onto the primary endpoint. The listed death is not assigned a treatment relationship in the registry record.

The registry record reports 0 analyses. It does not report estimates, confidence intervals, or statistical tests for the registered efficacy outcomes. The reason for termination, statistical analysis plan, sample-size justification, analysis populations, missing-data methods, and multiplicity approach are not reported in the registry record. The termination status therefore cannot be interpreted as evidence about the treatment's effects or the reason the study ended.

The registry's treatment description gives the listed schedule and stopping conditions, but does not supply the missing analytical details. The record also does not provide participant-level event data, so overlap among adverse-event terms cannot be assessed. These limitations restrict interpretation of both safety and efficacy; they do not establish that unreported outcomes were absent.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Talimogene Laherparepvec and Panitumumab for the Treatment of Locally Advanced or Metastatic Squamous Cell Carcinoma of the Skin — NCT04163952.
• Registry record last updated 2026-01-23; status last verified 2026-01.
• Results first posted 2024-01-18.
• 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

NCT04163952 is a terminated phase 1, single-group study sponsored by Rutgers, The State University of New Jersey. It evaluated talimogene laherparepvec with panitumumab in locally advanced or metastatic squamous cell carcinoma of the skin, with enrollment of 5. The registered primary endpoint concerns treatment-related adverse events of grade three or higher during follow-up up to 30 days.

The posted safety figures report serious adverse events among 2 of 5 participants at risk, other adverse events among 5 of 5 at risk, and 1 death. Anemia and abdominal pain are listed as top serious-event terms, each at 20.0%. The registry record reports 0 analyses and does not report results for the registered efficacy outcomes or the primary endpoint in its defined form. With no comparator, these data support only a limited descriptive account, not a comparative estimate of treatment effect.