The Selective Personalized Radio-Immunotherapy for Locally Advanced NSCLC Trial: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for The Selective Personalized Radio-Immunotherapy for Locally Advanced NSCLC Trial (NCT03523702), a na phase 2 study. The primary outcome is Progression-Free Survival (PFS).

2. Clinical Question

The study asks whether combining immunotherapy with a personalized radiotherapy course merits evaluation for locally advanced NSCLC, particularly when tumor PD-L1 expression is high. Its stated motivation is to explore this approach relative to standard chemotherapy and radiotherapy. That motivation should not be confused with a direct treatment comparison: the registry describes a single-group design, with allocation listed as NA and no masking.

The arm description distinguishes participants with PD-L1 expression at least 50% from those below 50%, but the description for the below-50% group is incomplete in the registry record. The primary endpoint description specifically concerns PFS after sequential pembrolizumab and radiotherapy for participants with PD-L1 expression at least 50%. The record therefore does not establish that the stated primary question applies identically to all participants enrolled.

In general, a single-group study can describe outcomes after a treatment strategy, but it cannot by itself separate treatment effects from the course participants might have experienced under another strategy. The registry record gives no concurrent control outcome against which to interpret the primary endpoint. The key result needed to answer the stated endpoint question—the 12-month PFS percentage—is not reported in the registry record.

3. Trial Design

SPRINT is a phase 2 clinical study of PembroRT for locally advanced NSCLC. The registry lists a single-group model, allocation as NA, and masking as none. Enrollment is listed as 25. The study status is completed, with a start date of 2018-08-30 and primary completion dated 2022-11-18.

The intervention is named PembroRT and is classified as a drug intervention. The arm description for participants with PD-L1 expression at least 50% specifies sequential pembrolizumab at 200mg every 3 weeks together with accelerated, dose-painted radiotherapy. The brief summary characterizes the radiotherapy as a personalized 4-week course. The record also mentions participants with PD-L1 expression below 50%, but the description of what they receive is truncated and is not reported in the registry record in complete form.

The registry identifies standard chemotherapy combined with radiotherapy as the standard treatment approach that motivates the study question. However, the design does not include a randomized control group for a direct comparison. The study's single-group structure means that outcomes describe participants in the treatment cohort; they do not estimate a randomized difference between PembroRT and standard treatment.

The primary endpoint is progression-free survival (PFS), expressed as the percentage of participants with PFS at 12 months. The registry also lists secondary outcomes involving freedom from distant metastasis, intrathoracic disease progression, overall survival, radiographic response by RECIST, and unplanned hospitalization. Details of the statistical analysis plan, endpoint assessment procedures, and analysis populations are not reported in the registry record. The record lists no analyses.

Although the study is marked completed, completion status alone does not supply outcome estimates. The registry record does not report the primary PFS percentage, uncertainty around that percentage, or results for the listed secondary outcomes. Consequently, the design and stated questions can be described, but treatment effects cannot be quantified from the registered results.

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: Of the 42 patients who were consented into the trial, 5 were excluded prior to randomization. 4 of these patients did not meet inclusion/exclusion criteria and 1 was excluded based on personal reasons. Of these 37 patients, based on assay results, 25 patients were determined to have a PD-L1 tumor expression level of ≥ 50% and 12 patients were observed to have a PD-L1 tumor expression level of \< 50%. The 25 patients with a PD-L1 tumor expression level ≥ 50% were enrolled into the study.

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 Progression-Free Survival (PFS), measured over 12 months.

The primary endpoint is progression-free survival at 12 months, reported as the percentage of participants who have PFS at that time. In general, PFS captures the period during which a participant is alive without documented disease progression; its exact operational definition depends on the trial's protocol and assessment rules. Those detailed rules are not reported in the registry record.

Assessing PFS at a specified time point turns a time-to-event outcome into a binary status for the reported endpoint: a participant either meets the definition of PFS at that point or does not. The resulting percentage can communicate the proportion reaching that status at the selected time. It is not the same as reporting the timing of every progression event, and it does not by itself describe how uncertainty or censoring was handled.

In general, a fixed-time PFS rate can be useful when the clinical question concerns the chance of remaining progression-free to a particular point in follow-up. It can also be easier to interpret than a relative measure such as a hazard ratio when the relevant time point is clear. However, interpretation depends on adequate follow-up and transparent definitions of progression, death, and missing assessments. These details are not reported in the registry record.

The stated timeframe is 12 months, but the registry record does not report the observed percentage, a confidence interval, or the number of participants contributing to the endpoint analysis. The endpoint's intended meaning is clear from its description; the posted record does not provide the result needed to assess its magnitude or precision.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What does a binary endpoint represent?

The primary endpoint is described as a percentage of participants with PFS at 12 months. In general, a binary endpoint classifies each participant according to whether a defined condition is met at a specified assessment point. The count meeting the condition and the number assessed are then used to describe a proportion. For this trial, the record states the endpoint definition at a high level, but does not report the observed count, the analysis denominator, or the resulting percentage.

A binary summary is relatively direct to understand, but it can hide important detail. It does not show when progression occurred, how follow-up varied across participants, or how participants without a complete assessment were treated. For a time-to-event outcome such as PFS, analysts often use methods that account for different follow-up times and censoring. The registry record does not report whether such methods were used or how the stated fixed-time rate was estimated.

How should uncertainty be understood?

In general, a confidence interval is an uncertainty summary around an estimate. It reflects the variability expected from sampling under the model and assumptions used for analysis. It is not a guarantee that the true value lies within a particular interval, nor does it account automatically for bias, missing data, or differences between the study population and another population. No confidence interval for the primary endpoint is reported in the registry record, so the estimate's statistical precision cannot be evaluated.

For a simple binary proportion, uncertainty depends in part on the number of observed outcomes and the number of participants contributing data. A result based on limited information may be imprecise even when its point estimate appears straightforward. The registry lists enrollment of 25, but that enrollment figure should not be assumed to equal the denominator for the primary endpoint. The endpoint analysis denominator is not reported in the registry record.

Why does the single-group design matter?

In general, random allocation helps balance measured and unmeasured prognostic factors across treatment groups, supporting a causal comparison. Here, the registry identifies a single-group model and no allocation. There is no concurrent randomized group receiving standard chemotherapy and radiotherapy. Therefore, any outcome description would characterize the PembroRT cohort rather than estimate a randomized contrast. A comparison with an external benchmark would require assumptions about comparability that are not documented in this registry record.

Masking is listed as none. In general, lack of masking can matter when outcomes involve clinical judgment, participant reporting, or decisions about additional care. Its relevance depends on the endpoint and how assessments are conducted. The record does not provide enough detail about outcome assessment procedures to determine whether, or how, the lack of masking influenced PFS assessment or other outcomes.

What do the planning assumptions mean?

The sample-size material is described as a planning illustration based on the observed effect, not as the trial's own design. Its stated assumptions include a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. For time-to-event illustrations, the stated quantity is the total number of events; for other illustrations, it is participants per arm. These assumptions describe hypothetical planning calculations, not the actual single-group design.

The planning description also refers to detecting a stated fraction of the observed effect. Such an illustration depends on the effect estimate used and the calculation assumptions. The registry record does not report an observed primary-endpoint effect or trial-specific sample-size justification. The illustrations must not be read as observed power, proof that the study was adequately powered, or evidence of a treatment effect. In particular, a hypothetical equal-allocation, two-arm calculation does not transform this single-group study into a randomized comparison.

In general, power is a design-stage probability calculated under specified assumptions about an effect, variability, significance level, and analysis. It is not a measure of how likely a result is to be true after data are observed. Post hoc calculations based on an observed effect are especially limited as summaries of evidence. The planning assumptions therefore provide context for hypothetical design choices, but do not replace the missing endpoint estimate and uncertainty.

What role does over-dispersion play?

In general, over-dispersion means that observed variability exceeds what a statistical model assumes. For count outcomes, a simple model may underestimate variability if events cluster or participants differ more than expected. For a binary outcome, analogous departures from a simple independent-proportion model can arise when observations are correlated or the population is heterogeneous. Ignoring excess variability can make standard errors too small and confidence intervals too narrow.

This is a general statistical consideration, not a reported feature of SPRINT's analysis. The record does not describe an over-dispersion assessment, a model for dependence, or a variance adjustment. It also does not report the primary endpoint analysis itself. No claim can therefore be made about whether over-dispersion occurred or whether an adjustment was used.

What can be concluded from the analysis record?

The registry identifies the primary outcome and lists secondary outcomes, but reports no analyses. It does not give the PFS rate at 12 months, uncertainty estimates, analysis populations, handling of incomplete observations, or analysis methods. Statistical interpretation is consequently limited to explaining the intended endpoint and the design constraints. The posted record does not support a numerical estimate of treatment effect or a comparative conclusion.

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("PembroRT Cohort")
n      <- c(25)
events <- c(19)
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  PembroRT Cohort  25  19  76.0  54.9  90.6  56.6  88.5  56.4  88.4

11. Multiplicity, Missing Data and Analysis Populations

The registry lists the primary PFS endpoint and secondary outcomes involving freedom from distant metastasis, intrathoracic disease progression, overall survival, radiographic response by RECIST, and unplanned hospitalization. It reports six outcome measures and no analyses. The registry record does not describe a multiplicity plan, such as a hierarchy of endpoints, adjustment for multiple testing, or a distinction between confirmatory and exploratory analyses.

In general, evaluating multiple outcomes can increase the chance that at least one result appears statistically notable by chance. A prespecified testing strategy can help readers understand how to interpret results across outcomes. Without a reported plan and analysis results, it is not possible to assess how multiplicity was handled in this study or whether any outcome claims were intended as confirmatory.

Missing-data methods are not reported in the registry record. For PFS, interpretation can depend on follow-up duration, censoring, missing assessments, and the rules for determining progression or death. The record does not specify how participants lacking a 12-month assessment were handled, whether missingness was explored, or whether sensitivity analyses were performed. No imputation or other missing-data procedure should be presumed.

The analysis populations are also not reported in the registry record. The enrollment figure does not establish how many participants were included in each endpoint analysis, whether eligibility or treatment exposure affected inclusion, or how participants with incomplete data were handled. These omissions limit assessment of both potential bias and precision. They do not show that the trial team failed to conduct these analyses; they mean that the registered record does not document them.

12. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

Deaths

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 0% reporting threshold.

Most frequent non-serious adverse event terms

The registry lists the PembroRT cohort with 25 participants at risk for serious adverse events and 0 affected. For other adverse events, it lists 25 at risk and 10 affected, and records 6 deaths. The serious and other adverse event figures are distinct categories in the registry and should be read as separate entries, not combined into a single outcome. No serious adverse event terms are listed.

These figures do not by themselves establish whether an event was caused by treatment. The registry record does not report the event definitions, observation period, severity breakdown for the other events, timing, attribution, or relationship of the deaths to treatment. It also does not give details on how adverse events were collected or whether follow-up was complete.

In general, a zero count in a registry category means no affected participants were recorded for that category in the stated entry; it does not prove that the treatment has no risk. Safety interpretation also depends on the duration and completeness of observation and the kinds of events monitored. The listed adverse event figures should therefore be treated as limited descriptive reporting, not as a complete assessment of safety or a comparison with another treatment.

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

The registry record establishes that SPRINT was a completed phase 2, single-group study of PembroRT for locally advanced NSCLC, with enrollment listed as 25. It identifies PFS at 12 months as the primary endpoint and gives a treatment description for the high-PD-L1 group. It also records several secondary outcomes and limited adverse-event counts. These registry entries describe the study's stated design and registered information.

The record does not report the primary PFS percentage, an uncertainty interval, or results for the secondary outcomes. It therefore does not show how often participants met the stated PFS definition at 12 months, how precise that estimate would be, or how the other outcomes varied. Without these results, no conclusion about the magnitude of an outcome in the cohort can be drawn from the registered record.

The study also does not include a randomized standard-treatment control group. The standard chemotherapy and radiotherapy regimen is part of the study's rationale, not a concurrent comparator. Even if a cohort outcome estimate were available, it would not alone establish the comparative effect of PembroRT versus standard treatment. General comparisons across studies would require assumptions about participant populations, outcome definitions, follow-up, and care that are not established in this record.

The safety entries are limited and do not document event timing, attribution, or comprehensive follow-up. They should not be interpreted as proof of absence of harm. The intended question is clinically relevant, but the posted registry information is insufficient to assess efficacy, comparative benefit, or the full safety profile. That distinction is important: a study can be completed and have a clearly stated endpoint without the registry record containing results adequate to answer that endpoint.

14. Why This Trial Matters Statistically

SPRINT illustrates the difference between a clearly stated clinical question and the evidence needed to answer it. Its primary endpoint specifies PFS at 12 months, and its treatment strategy combines sequential pembrolizumab with personalized radiotherapy. Those details make the intended outcome and intervention understandable. Yet the registry record does not report the endpoint result, so readers cannot assess the observed outcome or its statistical precision.

The design also highlights why comparator structure matters. The study summary frames standard chemotherapy and radiotherapy as the approach against which the strategy is motivated, but the registered model is single-group. A cohort outcome can describe what happened among participants treated in the study; it cannot supply a randomized estimate of the difference between treatment approaches. This distinction prevents a descriptive result from being overstated as a comparative treatment effect.

From a statistical reporting perspective, outcome estimates are most informative when accompanied by uncertainty, analysis denominators, endpoint definitions, handling of missing observations, and a clear analysis population. The registry record does not report these details for the primary endpoint. Their absence limits reproducibility and makes it difficult to distinguish imprecision from a genuinely uncommon or common outcome.

The listed adverse-event counts likewise show the need for context. Counts without event descriptions, attribution, and follow-up details are not a complete safety assessment. Overall, the trial matters as an example of a focused phase 2 question whose registered design can be described, while its posted results do not provide the information needed for statistical evaluation of the primary question or a comparison with standard treatment.

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.

Several limitations arise directly from the registered information. The most important is that the primary endpoint result is not reported. The registry identifies PFS at 12 months as the outcome of interest but provides no observed percentage, confidence interval, analysis denominator, or result interpretation. Secondary outcome estimates are also not reported.

The single-group design prevents a direct randomized comparison with standard chemotherapy and radiotherapy. The standard approach appears in the study summary as context, not as a concurrent control arm. As a result, the registered information cannot estimate a treatment contrast or rule out differences attributable to patient characteristics, follow-up, or other factors.

The registry description for participants with PD-L1 expression below 50% is incomplete. This limits understanding of the treatment strategy for that subgroup and how it relates to the primary endpoint description, which focuses on participants with PD-L1 expression at least 50%. The analysis populations and subgroup results are not reported.

Important analytic details are also not reported in the registry record, including the operational PFS definition, assessment schedule, censoring rules, missing-data handling, multiplicity approach, and methods used to estimate the endpoint. The record does not describe how the absence of masking affected outcome assessment. These gaps prevent evaluation of potential sources of bias and the robustness of any result.

Safety reporting is limited to event counts and does not include event terms, timing, attribution, or details of follow-up. The record's completion status does not resolve these gaps. These limitations concern what can be learned from the registry record; they do not establish what analyses or documentation may exist outside it.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: The Selective Personalized Radio-Immunotherapy for Locally Advanced NSCLC Trial — NCT03523702.
• Registry record last updated 2026-04-09; status last verified 2026-04.
• Results first posted 2024-12-03.
• 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

SPRINT is a completed phase 2, single-group study sponsored by Montefiore Medical Center. The registry lists enrollment of 25, no masking, and allocation as NA. The recorded study dates are 2018-08-30 for start and 2022-11-18 for primary completion.

The intervention is PembroRT, described for participants with PD-L1 expression at least 50% as sequential pembrolizumab and accelerated, dose-painted radiotherapy. The primary endpoint is the percentage with PFS at 12 months. Standard chemotherapy and radiotherapy are discussed as the motivating treatment approach, but there is no randomized control group.

The record lists secondary outcomes and adverse-event counts, but no analyses. It does not report the primary endpoint result, uncertainty, analysis populations, or detailed statistical methods. The registered information therefore describes the study question and design but does not permit assessment of the primary outcome or a comparative treatment effect.