This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for Durvalumab, Tremelimumab and Hypofractionated Radiation Therapy in Treating Patients With Recurrent or Metastatic Head and Neck Squamous Cell Carcinoma (NCT03522584), a na phase 1, phase 2 study. The primary outcome is Number of Patients With Adverse Effects Graded According to Common Terminology Criteria for Adverse Events (CTCAE) v. 4.0.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT03522584 |
| Phase | Phase 1, Phase 2 |
| Condition | Metastatic Head and Neck Squamous Cell Carcinoma, Recurrent Head and Neck Squamous Cell Carcinoma |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 6 |
| Arms in the primary outcome | n/a |
| Lead sponsor | University of Washington |
| Results posted | Yes |
2. Clinical Question
Population
People with recurrent or metastatic head and neck squamous cell carcinoma were the intended population. The official title further specifies that participants had previously received immune checkpoint inhibitors. The record lists six enrolled participants. It does not report a detailed description of the enrolled participants’ clinical characteristics in the information available for this analysis.
Intervention
The study evaluated a treatment approach involving durvalumab, tremelimumab, and hypofractionated image-guided radiation therapy. The intervention list also includes stereotactic body radiation therapy and laboratory biomarker analysis. The registry description frames the trial as an assessment of side effects as well as a possible treatment approach; this does not establish that the combination improves outcomes.
Comparator
There was no separate comparison group. The record describes a single-group study, with no randomized allocation and no masking. Consequently, the study does not provide a like-for-like control arm for estimating how outcomes differ from another treatment or from no study treatment.
Primary question
The primary endpoint counts participants with adverse effects graded using CTCAE version 4.0. The stated observation period begins with study treatment and continues up to 3 months after the last study treatment, up to 38 months. The record also lists response rate, progression-free survival, and overall survival as secondary outcomes, but their results are not reported in the registry record.
3. Trial Design
The registry describes a phase I/II, single-group study sponsored by the University of Washington. The study began on 2018-05-17, had a primary completion date of 2021-12-16, and is listed as terminated. Six participants were enrolled. The reason for termination is not reported in the registry record, so the status alone cannot explain why recruitment or treatment ended.
The study has no randomized allocation and no masking. Because there is only one treatment group, the design can describe events occurring among participants who received the study treatment, but it cannot make a controlled comparison between treatment strategies. Any outcomes observed in this group may also reflect participants’ underlying disease and other influences that the record does not describe. The absence of a control group is especially relevant when interpreting response, survival, or safety counts: a count in one group does not establish what would have happened under another approach.
The treatment group is described as receiving tremelimumab, durvalumab, HIGRT, and SBRT. The brief regimen description states that participants received tremelimumab and durvalumab intravenously on the first day of treatment, with treatment repeating on one of two schedules subject to disease progression or unacceptable toxicity. The description is truncated after stating that participants then receive durvalumab, so the complete treatment schedule is not reported in the registry record. The protocol’s dose details and the criteria used to select between schedules are also not reported in the registry record.
The primary endpoint concerns adverse effects graded according to CTCAE version 4.0. The registry states that toxicities are to be summarized as counts and percentages by type. It also identifies response rate, progression-free survival, and overall survival as secondary outcomes. The duration and exact assessment definitions for those secondary endpoints are not reported in the registry record. There are no posted analyses listed, so no inferential comparison or adjusted effect estimate can be described.
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
| Stage | Treatment (Tremelimumab, Durvalumab, HIGRT, SBRT) |
|---|---|
| STARTED | 6 |
| COMPLETED | 6 |
| NOT COMPLETED | 0 |
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.
| Characteristic | Unit | Treatment (Tremelimumab, Durvalumab, HIGRT, SBRT) |
|---|---|---|
| Participants analysed | 6 | |
| Age, Categorical: <=18 years | Participants | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 4 |
| Age, Categorical: >=65 years | Participants | 2 |
| Age, Continuous | years | 64 (47 to 67) |
| Sex: Female, Male: Female | Participants | 0 |
| Sex: Female, Male: Male | Participants | 6 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 |
| Race (NIH/OMB): Asian | Participants | 2 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 |
| Race (NIH/OMB): Black or African American | Participants | 0 |
| Race (NIH/OMB): White | Participants | 4 |
| Race (NIH/OMB): More than one race | Participants | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| Region of Enrollment: United States | participants | 6 |
6. Primary Endpoint
The registry lists the primary outcome as Number of Patients With Adverse Effects Graded According to Common Terminology Criteria for Adverse Events (CTCAE) v. 4.0, measured over From the start of study treatment up to 3 months after last study treatment, up to 38 months.
| Element | Registry entry |
|---|---|
| Result type | Count Of Participants |
| Measure of spread | not applicable |
| Unit | Participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint counts participants with adverse effects graded according to CTCAE version 4.0. Its stated timeframe starts with study treatment and continues until 3 months after the last study treatment, up to 38 months. The registry’s endpoint description says toxicities will be summarized by type using participant counts and percentages. A participant count answers how many people in the group were recorded with an event; it is not a measure of event severity on its own and does not describe how often an event occurred in an individual participant.
Safety endpoints are used to characterize the adverse effects recorded while participants receive a treatment regimen. In a single-group study, such counts can describe the observed safety experience in that group, but they cannot by themselves distinguish effects of treatment from effects of the disease or other factors. Interpretation also depends on how events were defined, collected, graded, and attributed. Attribution procedures and details of event collection are not reported in the registry record.
The registry lists six participants in the treatment group and reports that six had other adverse events and zero had serious adverse events in the posted safety figures. These categories should not be collapsed into one overall safety conclusion: the record distinguishes serious events from other events. It also lists six deaths, but the timing, causes, and relationship to study treatment are not reported in the registry record. The available information does not give a complete event-by-event account or uncertainty intervals for the primary endpoint.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The record describes a small, single-group study with six enrolled participants. In the posted safety figures, six participants are listed as at risk for other adverse events and six are listed as affected; six are also listed as at risk for serious adverse events, with zero affected. The death count is six. These are descriptive counts from the registry record, not estimates from a comparison between treatment groups. The record does not report confidence intervals, hypothesis tests, or an adjusted analysis for these safety figures.
The primary endpoint is framed as the number of participants with adverse effects graded using CTCAE version 4.0. The safety information available is not a complete presentation of every endpoint result: it supplies group-level counts for the adverse-event categories, while the primary endpoint description says toxicities are to be summarized by type. Specific toxicity terms are not listed among the serious adverse-event terms in the record. The absence of listed serious terms should not be read as a detailed account of all adverse effects; the registry lists zero participants affected by serious adverse events and six affected by other adverse events.
The six deaths warrant careful, literal description. The registry safety figures list six deaths in the group of six participants. The record does not state when the deaths occurred, their causes, whether each was considered related to treatment, or how the death count relates to follow-up completion. Without those details, no causal interpretation is justified. In particular, a death count alone cannot establish that study treatment caused deaths or that deaths were unrelated to treatment.
The record names response rate, progression-free survival, and overall survival as secondary outcomes, but does not report outcome estimates for them. It also lists zero analyses. Therefore, there is no reported response estimate, time-to-event summary, uncertainty interval, or statistical test to interpret for those outcomes. The trial’s stated interest in a treatment combination does not substitute for an observed efficacy result.
Small groups give limited descriptive resolution: each participant represents a substantial part of the group, so the observed counts can change markedly if even one person’s outcome differs. This is a general statistical point, not a recalculation of the registry data. In addition, without a control group, the record cannot estimate a relative effect against another treatment. The results should be understood as a sparse description of events recorded in this study, not as evidence for a comparative treatment effect or a precise estimate for a broader population.
9. Statistical Methods Explained
The design and posted information determine what statistical claims can be made. The study is identified as phase I/II and single-group, with no randomized allocation and no masking. The enrollment is six. The primary endpoint is a count of participants with adverse effects graded according to CTCAE version 4.0. The record states that toxicity summaries are intended to include counts and percentages by type, but it does not provide a posted analysis plan or inferential results. No analyses are listed in the registry record.
What does a participant count describe?
A participant count describes how many people in a defined group meet an event definition during a specified observation period. For the primary endpoint, the counting unit is the participant, not the number of separate episodes. If one person experiences the same type of event more than once, a participant-level count generally does not communicate the repeated-event frequency. The registry endpoint specifies participants, and the safety figures distinguish participants at risk from participants affected. Event-level details and rules for handling repeated events are not reported in the registry record.
Counts are useful for describing the observed group, especially when the endpoint is safety. They are not, by themselves, a measure of precision or a causal estimate. A count needs context: the group size, the event definition, the follow-up period, and the completeness of observation all matter. Here, the record gives six participants in the group and a timeframe for the primary endpoint, but it does not report individual follow-up durations or detailed completeness information.
Why is a control group important?
A treatment comparison asks how outcomes differ between groups that received different strategies. Randomization, when used, is intended to make groups comparable on average with respect to factors that could affect outcomes. This study has no randomized comparison and is listed as single-group. Accordingly, the observed counts cannot be contrasted with a concurrently assigned control group. A comparison with an external population would require details and assumptions that are not reported in the registry record.
Masking can reduce the influence of knowledge of treatment assignment on some assessments and decisions. The record lists no masking. This fact does not show that outcome assessment was biased; it means the registry does not describe a masked design. How adverse events were elicited and graded, and whether assessors were independent, are not reported in the registry record.
What would uncertainty intervals add?
A confidence interval is a general statistical tool for expressing the precision of an estimated quantity under a specified method and assumptions. For a single-group safety proportion, an interval can communicate how uncertain the underlying event rate remains when the sample is small. The registry does not report confidence intervals for the safety counts, and none should be inferred from the counts alone. A narrow-looking count or a zero observed count is not proof that the underlying risk is zero.
For comparative effects, intervals would describe uncertainty around a contrast between groups, such as a difference or ratio, but this study has no control group and the registry lists no analyses. General statistical methods cannot replace the missing comparison data. Any proposed external comparator or model would introduce assumptions not documented in the registry record.
Why do analysis plans and outcome definitions matter?
A statistical analysis plan usually explains how outcomes will be defined and analyzed, which participants will be included, how missing observations will be handled, and how multiple outcomes will be interpreted. Those details help readers understand whether a result was selected from many possible analyses and whether the analysis matches the study question. A statistical plan is not reported in the registry record. The registry entries identify the primary endpoint and named secondary outcomes but do not specify analysis populations, missing-data methods, or multiplicity procedures.
Multiplicity is the general issue that arises when several outcomes or statistical tests are considered: the chance of at least one apparently notable result can increase as more tests are performed. This study names several secondary outcomes, but no analyses are listed and no multiplicity method is reported. There are therefore no reported p-values or outcome estimates whose interpretation depends on a stated adjustment.
Over-dispersion is a general concern for count data when variability exceeds what a chosen model expects. It can matter in analyses of event counts, particularly when repeated events per person are modeled. The primary endpoint is specified as a count of participants with an event rather than a count of all event episodes. The registry does not report a statistical model for these data, so it is not possible to say whether over-dispersion was assessed or relevant to an analysis.
Sample-size planning is distinct from observed evidence. A planning calculation estimates what enrollment might be needed under assumptions about an effect, variability, allocation, and statistical criteria. Such an illustration is not observed power and does not establish that a study could detect an effect. A sample-size justification and the assumptions used for the trial’s own design are not reported in the registry record. The six participants enrolled are an observed enrollment count, not evidence that the study had adequate precision for safety or efficacy questions.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists response rate, progression-free survival, and overall survival as secondary outcomes in addition to the primary safety endpoint. Considering multiple outcomes can create multiplicity: as a general statistical matter, the more tests or outcome definitions examined, the greater the opportunity for a chance finding to appear noteworthy. How the study planned to address multiplicity is not reported in the registry record. No posted analyses or p-values are listed, so there are no reported inferential findings for which an adjustment can be evaluated.
The registry does not report the analysis populations used for the primary or secondary outcomes. For example, it does not state whether analyses were intended to include all enrolled participants, only participants who began treatment, or another defined group. These are general choices that can affect interpretation; the record does not identify which approach was used.
Missing-data handling is also not reported in the registry record. The available safety figures list six participants at risk in each adverse-event category, but do not describe whether all participants completed the stated observation period or how incomplete follow-up was handled. For the secondary outcomes, no results or missingness summaries are reported. Methods such as imputation, censoring rules, or sensitivity analyses cannot be inferred from the endpoint names alone.
These reporting gaps do not establish that a particular method was or was not used in study conduct. They mean the registry record does not document the methods needed to assess analysis-population choices, missing outcomes, or multiplicity. As a result, the posted information supports only a limited descriptive reading of the safety counts.
11. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| Treatment (Tremelimumab, Durvalumab, HIGRT, SBRT) | 0 | 6 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Treatment (Tremelimumab, Durvalumab, HIGRT, SBRT) | 6 of 6 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Treatment (Tremelimumab, Durvalumab, HIGRT, SBRT) | 6 of 6 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Treatment (Tremelimumab, Durvalumab, HIGRT, SBRT) |
|---|---|---|
| Fatigue | General disorders | 4 of 6 |
| Weight Loss | Metabolism and nutrition disorders | 3 of 6 |
| Cough | Respiratory, thoracic and mediastinal disorders | 2 of 6 |
| Fever | Infections and infestations | 2 of 6 |
| Headache | General disorders | 2 of 6 |
| Anorexia | Metabolism and nutrition disorders | 1 of 6 |
| Concentration Impairment | Nervous system disorders | 1 of 6 |
| Depression | Nervous system disorders | 1 of 6 |
| Diarrhea | Gastrointestinal disorders | 1 of 6 |
| Dizziness | Nervous system disorders | 1 of 6 |
The posted safety figures list six participants at risk for serious adverse events and zero affected. For other adverse events, six participants are listed at risk and six affected. The record also lists six deaths in the treatment group. These counts refer to distinct safety fields; they should not be treated as interchangeable outcomes or combined into a new summary.
The serious-adverse-event field reports no affected participants, but a zero count in a group of six does not establish that the underlying risk is zero. It describes only what is recorded for this group. The other-adverse-event count indicates that all six participants were recorded as affected in that category; the record does not provide the specific types, grades, timing, duration, or participant-level overlap of those events in the information.
The death count should be read with particular restraint. The registry does not report the timing or cause of death, attribution to treatment, or the relationship between death and the specified adverse-event follow-up period. Thus, the count alone cannot support a statement about treatment causality. The registry also does not list serious adverse-event terms, and that absence does not supply further detail about the other adverse events.
12. What the Result Does, and Does Not, Mean
The posted record supports a narrow descriptive statement: in a single treatment group of six participants, six were listed as affected by other adverse events, zero were listed as affected by serious adverse events, and six deaths were recorded in the safety figures. These observations summarize what is entered in the registry. They do not provide a controlled estimate of treatment effect, nor do they explain the timing, causes, or attribution of the deaths.
The record does not report results for response rate, progression-free survival, or overall survival. Although these outcomes are named, their inclusion in a registry entry is not evidence that they improved or worsened. No efficacy estimate or comparative analysis is available in the record for interpretation. No confidence intervals or p-values are listed, so the precision of any efficacy estimate cannot be assessed from the posted information.
The study’s single-group design limits causal conclusions. Without a control group, outcomes observed among participants receiving the regimen cannot show how those same outcomes would compare under another strategy. A small enrollment further limits how well the observed counts characterize people beyond the participants in this study. This is a general limitation of sparse data, not a claim that the recorded counts are inaccurate.
The results also do not explain why the study was terminated. The registry lists its status as terminated and gives the primary completion date, but the reason for termination is not reported in the registry record. It would be speculative to attribute the status to safety, efficacy, recruitment, or any other cause.
Overall, the registry documents a study intended to evaluate a combined immunotherapy and radiation approach, with toxicity as the primary endpoint. The posted information offers limited safety counts but no reported efficacy analyses. It should be read as a description of this small study record, not as proof that the regimen is beneficial, ineffective, safe, or unsafe in a broader population.
13. Why This Trial Matters Statistically
This trial is statistically instructive because its design and reporting place clear boundaries around what the results can answer. A phase I/II label and a treatment rationale do not determine whether an observed outcome is caused by treatment. The single-group structure means the registry can describe recorded events among treated participants, but it cannot estimate a treatment contrast against a concurrent control group.
The small enrollment makes the distinction between a count and a stable estimate especially important. Counts of affected participants can be useful for documenting what happened in the group. They should not be mistaken for precise estimates of event rates in a broader population, particularly when no uncertainty intervals or detailed follow-up information are reported. A zero count also remains a finite-sample observation rather than proof of no underlying risk.
The record offers another useful lesson: named outcomes and posted outcome analyses are different things. Response rate, progression-free survival, and overall survival appear as secondary outcomes, but their results are not reported in the registry record. Without results, definitions, analysis populations, and uncertainty measures, those endpoint names cannot support conclusions about efficacy.
Finally, the safety fields illustrate why context is essential. The serious-event count, other-event count, and death count describe different aspects of the registry record. The absence of details on event attribution and timing prevents causal interpretation. Statistical reading therefore involves more than repeating counts: it requires identifying what was measured, which comparisons are absent, and what information remains unreported.
14. 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 trial-specific limitations constrain interpretation. Enrollment was six, and the study had a single treatment group. The design therefore provides no randomized control comparison, and the small group gives limited information about how representative the observed safety counts may be of a wider population. The record does not report participant characteristics beyond the disease setting and prior immune checkpoint inhibitor treatment described in the official title.
The study is listed as terminated, but the reason is not reported in the registry record. The treatment description is truncated after the statement that participants then receive durvalumab, leaving the full regimen and schedule unavailable in the record. Dose details, the rationale for the alternate schedules, and adherence information are not reported.
The safety figures do not include detailed event terms, grades, timing, duration, attribution, or participant-level event histories. The death count is not accompanied by causes or treatment-relatedness assessments. The record also does not report follow-up completeness, missing-data methods, or how participants who did not complete treatment were handled.
Although secondary outcomes are listed, their results are not reported. The registry lists zero analyses and provides no confidence intervals, p-values, analysis populations, statistical plan, or multiplicity approach. Sample-size justification and the trial’s own design assumptions are not reported in the registry record. These limitations prevent assessment of efficacy, statistical precision, and many aspects of the safety evaluation beyond the descriptive counts.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Durvalumab, Tremelimumab and Hypofractionated Radiation Therapy in Treating Patients With Recurrent or Metastatic Head and Neck Squamous Cell Carcinoma — NCT03522584.
- Registry record last updated 2023-06-12; status last verified 2023-06.
- Results first posted 2023-06-12.
- 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.
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18. Record Summary
The registry record describes a phase I/II, single-group study of durvalumab, tremelimumab, and hypofractionated radiation for recurrent or metastatic head and neck squamous cell carcinoma. The official title specifies prior treatment with immune checkpoint inhibitors. The study enrolled six participants, was sponsored by the University of Washington, and is listed as terminated. The primary endpoint counts participants with CTCAE version 4.0 adverse effects; response rate, progression-free survival, and overall survival are named as secondary outcomes.
The posted safety figures list six participants affected by other adverse events, zero affected by serious adverse events, and six deaths. No efficacy analyses are reported in the registry record, and no analyses are listed. The reason for termination, causes and attribution of deaths, analysis populations, missing-data procedures, and statistical plan are not reported. The single-group design and limited enrollment support a descriptive reading only, not a controlled treatment-effect conclusion.