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 Photodynamic Therapy Using HPPH in Treating Patients With Advanced Non-Small Cell Lung Cancer That Blocks the Air Passages (NCT00528775), a na phase 2 study. The primary outcome is Tumor Response.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00528775 |
| Phase | Phase 2 |
| Condition | Lung Cancer |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 6 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Roswell Park Cancer Institute |
| Results posted | Yes |
2. Clinical Question
Population
The study concerned patients with advanced non-small cell lung cancer that obstructed the air passages, described in the official title as advanced obstructing endobronchial lung cancer. The registry record lists lung cancer as the condition. Further eligibility criteria, such as disease characteristics or prior treatment requirements, are not reported in the registry record.
Intervention
The intervention combined HPPH with an endoscopic procedure. The arm description states that patients would receive 4 mg/m2 HPPH with light-exposure precautions, followed approximately 2 days later by endoscopic treatment using 150J/cm of 665 +-5nm light. The study rationale describes HPPH as a drug activated by a particular kind of light.
Comparator
There was no separate control group. The registry describes a single-group study, with allocation listed as NA and masking as NONE. The record therefore does not set up a randomized or masked comparison of HPPH photodynamic therapy against another treatment or against no intervention.
Primary question
The primary outcome was tumor response at 6 months. In general, a tumor-response endpoint asks whether a tumor meets a predefined response criterion after treatment; the specific response definition and assessment rules are not reported in the registry record. The record states that, because of early termination and an inadequate number of patients, no patients were analyzed for this endpoint. Thus, the clinical question was registered, but the record does not provide an analyzed response result.
3. Trial Design
This was a phase II study of photodynamic therapy using HPPH for advanced obstructing endobronchial lung cancer. The registry identifies its model as single group, with enrollment of 6. Allocation is listed as NA and masking as NONE. These design features mean the record describes one group receiving the intervention, not a randomized comparison between treatment groups.
The listed intervention included HPPH and an endoscopic procedure. The arm description specifies 4 mg/m2 HPPH with light-exposure precautions, followed approximately 2 days later by endoscopic delivery of 150J/cm of 665 +-5nm light. The registry's rationale states that HPPH becomes active when exposed to a certain kind of light. Additional operational details, including how treatment delivery was monitored or modified, are not reported in the registry record.
The study start is recorded as 2007-08, and primary completion as 2009-11. Its status is TERMINATED. The sponsor is Roswell Park Cancer Institute. The record attributes the absence of primary endpoint analyses to early termination and an inadequate number of patients; it does not give further detail about the reason for termination or the enrollment process.
Five outcome measures are listed. The primary measure was tumor response at 6 months. Secondary measures concerned palliation of symptoms assessed by the Pulmonary Symptom Scale, HPPH concentration in tumor, STAT3 cross-links assessed by Western blotting, and inflammation and apoptosis assessed by immunohistochemistry. The registry record does not report results for these outcomes or specify the details of their analysis.
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 | HPPH |
|---|---|
| STARTED | 6 |
| COMPLETED | 5 |
| NOT COMPLETED | 1 |
Reasons for not completing this period:
| Reason | HPPH |
|---|---|
| Other not specified | 1 |
Analysis population for the primary outcome, as defined in the registry: Due to the study's early termination and inadequate number of patients, no patients were analyzed.
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: All treated and eligible patients
| Characteristic | Unit | HPPH |
|---|---|---|
| Participants analysed | 6 | |
| Age, Continuous | years | 64 (SD 12.52) |
| Sex: Female, Male: Female | Participants | 3 |
| Sex: Female, Male: Male | Participants | 3 |
6. Primary Endpoint
The registry lists the primary outcome as Tumor Response, measured over 6 months.
| Element | Registry entry |
|---|---|
| Result type | N/A |
| Measure of spread | not applicable |
| Unit | not stated |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint was tumor response, with a timeframe of 6 months. A tumor-response outcome is generally used to describe whether a tumor meets a prespecified definition of response after an intervention. It can provide a structured clinical measure for a treatment study, but its interpretation depends on the exact criteria, assessment procedures, and analysis rules used.
The registry record does not state the response criteria, how tumor measurements were made, whether response required confirmation, or how deaths or unevaluable assessments were handled. Those details should not be inferred from the endpoint label alone. The record does specify that no patients were analyzed for tumor response because the study ended early and the number of patients was inadequate.
Consequently, there is no reported response estimate to interpret. The endpoint remains a registered study question rather than an observed result in this record. In general, an endpoint's planned timeframe identifies when its outcome is intended to be assessed; it does not establish that an assessment was completed or that data were available for analysis.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The central statistical fact is that the registry record reports no patients analyzed for the primary outcome, tumor response at 6 months. It attributes this to early termination and an inadequate number of patients. As a result, the record does not provide an estimate of tumor response, a confidence interval, or a test of an efficacy hypothesis. Those quantities are not reported in the registry record.
This is different from a study that analyzes participants and finds little evidence of a response. No analyzed response result is available, so the data in this record cannot establish either the presence or absence of a treatment effect. In general, an estimate describes the observed outcome in the analyzed population, while a confidence interval describes uncertainty around that estimate under the analysis assumptions. Neither can be interpreted for the primary endpoint when no patients were analyzed for it.
The single-group design also limits what could be learned even if an outcome estimate had been reported. Without a concurrent control group, a change or response in the treated group would not by itself distinguish an intervention effect from other explanations, such as the course of disease or other care. This is a design limitation, not a claim about what occurred in these participants. The registry record contains no randomized comparator and no like-for-like control comparison.
The adverse-event summary is separate from the primary efficacy endpoint. It lists 6 participants at risk for serious adverse events, with 5 affected, and 6 at risk for other adverse events, with 4 affected. Serious terms listed include Anaemia, Supraventricular tachycardia, Death, Pneumonia, Intubation complication, and Neuropathy, each at 16.7%. These descriptive entries do not supply a comparative estimate or establish that an event was caused by the intervention. The registry's deaths field is not populated, while Death appears among the listed serious terms; the record does not provide enough detail to resolve that distinction.
Accordingly, interpretation should stay close to what was recorded: the study was terminated, the primary endpoint was not analyzed, and adverse-event summaries are available. The record does not support a quantitative conclusion about tumor response or a comparison of safety against another group. Missing statistical results are not evidence of no effect, and descriptive event listings do not answer the efficacy question.
9. Statistical Methods Explained
Statistical interpretation begins with the design and the data that were actually analyzed. This study is recorded as phase II and single group, with enrollment of 6. Allocation is listed as NA, masking as NONE, and the primary tumor-response outcome has no analyzed patients. The record reports 0 analyses. These registry entries mean that the primary endpoint has no reported analysis result to summarize; they do not indicate that a test was performed and found no difference.
What an estimate would represent
General statistical explanation: for a binary tumor-response outcome, an analysis might estimate the proportion of analyzed participants who meet a defined response criterion. That proportion would depend on the response definition and the participants included in the analysis. The registry record does not report the response criteria or an analyzed response proportion. It therefore does not support reconstructing an estimate from the endpoint title, enrollment, or adverse-event summaries.
A confidence interval is a range of values generated by a statistical procedure to express uncertainty around an estimate. Its width depends, among other things, on the amount and variability of the data and on the method used. With no patients analyzed for the primary endpoint, there is no response estimate or confidence interval reported to interpret. A confidence interval should not be invented or inferred from the total enrollment.
Why the design matters
General statistical explanation: a single-group study can describe outcomes in the treated group, but it cannot make a direct randomized comparison with a separate control group. Even a clearly measured outcome would need cautious interpretation because the design does not provide a concurrent control for separating an intervention effect from other influences. Here, the primary outcome was not analyzed, so there is no treated-group response estimate either.
Random allocation, when used, helps make groups comparable on average with respect to both measured and unmeasured factors. This record lists allocation as NA and describes a single-group model. It therefore does not describe a randomized comparison. Masking is listed as NONE; the registry does not explain whether outcome assessors were masked by any other process.
Planning assumptions and observed evidence
General statistical explanation: sample-size planning uses assumptions about the outcome, the effect a study aims to detect, and the analysis method. A planning calculation is not evidence that the assumed effect occurred. Any sample-size illustrations associated with this record are described as planning illustrations based on an observed effect, using a two-sided significance level of 0.05, equal allocation between two hypothetical arms, and a normal approximation. They are not the trial's own design or observed power. The record does not report an analyzed primary response effect from which to interpret efficacy.
Observed power is not a substitute for an estimate and its uncertainty. In general, after a study, the most informative quantities are the observed effect estimate and its confidence interval, interpreted in light of the design and analysis. The registry record supplies neither for tumor response. Planning calculations cannot fill that gap or turn a study with no analyzed primary endpoint into an efficacy comparison.
Counts, percentages, and event interpretation
General statistical explanation: event counts and percentages describe what is recorded within a group, but their meaning depends on the denominator, follow-up period, event definitions, and whether entries count participants or repeated events. The adverse-event information lists participants at risk and affected, along with serious-event terms and percentages. The record does not report enough methodological detail to infer event timing, recurrence, attribution, or the precise relationship between each term and the participants affected.
Over-dispersion is a general issue that can arise when event counts vary more than a simple statistical model assumes. It can affect uncertainty estimates for count outcomes. The registry record does not report an event-count model or enough repeated-event detail to assess over-dispersion, and no such modeling result should be assumed.
Overall, the available record supports describing the trial's design, endpoint, termination, and adverse-event summaries. It does not support an inferential analysis of the primary outcome. Statistical methods can clarify what an analysis would mean, but they cannot recover an outcome estimate that the registry says was not analyzed.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists five outcome measures: tumor response as the primary outcome, plus four secondary measures concerning symptom palliation, HPPH concentration in tumor, STAT3 cross-links, and inflammation and apoptosis. Multiple outcomes can create a multiplicity issue when several statistical tests are conducted, because the chance of at least one apparently notable result can increase as the number of tests grows. General approaches include prespecifying a primary outcome, controlling an overall error rate, or treating secondary analyses as exploratory. The registry record does not report a multiplicity adjustment or an analysis plan describing how multiple outcomes were handled.
The record lists 0 analyses and explicitly states that no patients were analyzed for the primary tumor-response endpoint. It does not report results or analyses for the secondary outcomes. Accordingly, there are no reported outcome tests whose multiplicity handling can be assessed. The absence of reported analyses should not be interpreted as evidence that multiplicity was handled in a particular way.
Missing-data methods and analysis populations are also not described. The record explains that early termination and an inadequate number of patients led to no primary endpoint analysis, but it does not specify an intention-to-treat population, a per-protocol population, rules for unevaluable participants, or methods for handling missing outcome assessments. Those details are not reported in the registry record. General statistical practice distinguishes participants enrolled, treated, and included in an analysis; the record gives enrollment of 6 but does not provide those separate analysis-population counts for efficacy.
Without outcome-level data, analysis populations, and prespecified missing-data rules, it is not possible to assess how missingness might affect an estimate. There is no reported primary estimate to compare across alternative assumptions, and no basis for evaluating whether secondary-outcome testing was adjusted or exploratory.
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 |
|---|---|---|---|
| HPPH | 5 | 6 | 83.3% |
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 |
|---|---|
| HPPH | 4 of 6 |
Most frequent serious adverse event terms
| Event term | Organ system | HPPH |
|---|---|---|
| Anaemia | Blood and lymphatic system disorders | 1 of 6 |
| Supraventricular tachycardia | Cardiac disorders | 1 of 6 |
| Death | General disorders | 1 of 6 |
| Pneumonia | Infections and infestations | 1 of 6 |
| Intubation complication | Injury, poisoning and procedural complications | 1 of 6 |
| Neuropathy | Nervous system disorders | 1 of 6 |
| Bronchial obstruction | Respiratory, thoracic and mediastinal disorders | 1 of 6 |
| Respiratory distress | Respiratory, thoracic and mediastinal disorders | 1 of 6 |
| Hospitalisation | Surgical and medical procedures | 1 of 6 |
| Tracheostomy | Surgical and medical procedures | 1 of 6 |
Most frequent non-serious adverse event terms
| Event term | Organ system | HPPH |
|---|---|---|
| Bronchial obstruction | Respiratory, thoracic and mediastinal disorders | 2 of 6 |
| Anaemia | Blood and lymphatic system disorders | 1 of 6 |
| Leukocytosis | Blood and lymphatic system disorders | 1 of 6 |
| White blood cell disorder | Blood and lymphatic system disorders | 1 of 6 |
| Atrial fibrillation | Cardiac disorders | 1 of 6 |
| Asthenia | General disorders | 1 of 6 |
| Pyrexia | General disorders | 1 of 6 |
| Fall | Injury, poisoning and procedural complications | 1 of 6 |
| Sunburn | Injury, poisoning and procedural complications | 1 of 6 |
| Haemoglobin | Investigations | 1 of 6 |
Serious events with the highest arm-level rate: anaemia (16.7%), supraventricular tachycardia (16.7%), death (16.7%), pneumonia (16.7%), intubation complication (16.7%).
The registry lists 6 participants at risk for serious adverse events, with 5 affected. For other adverse events, it lists 6 at risk and 4 affected. These are descriptive counts in the HPPH group; the record does not provide a control group for comparison or establish that the events were caused by the intervention.
The serious-event terms listed are Anaemia, Supraventricular tachycardia, Death, Pneumonia, Intubation complication, and Neuropathy. Each is listed at 16.7%. These entries should be read as registry event summaries, not as a basis for ranking risks or comparing treatments. The record does not report the event definitions, timing, duration of follow-up, or whether an individual could contribute more than one listed term.
The adverse-event group has 6 participants at risk, while the primary outcome has no patients analyzed. These are different reporting categories and should not be conflated. The deaths field is not populated, although Death appears as a serious-event term at 16.7%. The registry record does not clarify the relationship between that term and the deaths field, nor does it report an attribution to HPPH.
12. What the Result Does, and Does Not, Mean
The record establishes that a phase II, single-group study of HPPH photodynamic therapy was registered for advanced obstructing endobronchial lung cancer, with tumor response at 6 months designated as the primary outcome. It also records that the study was terminated and that no patients were analyzed for that endpoint because of early termination and an inadequate number of patients. These are the key details for interpreting the study's clinical result.
The record does not provide a tumor-response estimate, confidence interval, or statistical test. It therefore does not show how many analyzed patients responded or how uncertain a response estimate might have been. No conclusion that HPPH did or did not produce tumor response can be drawn from an endpoint that was not analyzed. A missing result is not equivalent to a finding of no effect.
The study's single-group design means there is no randomized control group against which outcomes could be compared. Even if a response result were available, the design would not support a direct randomized comparison with another treatment. This distinction matters because descriptive observations within one group and estimates of comparative treatment effects answer different questions.
Safety summaries are recorded, including participants affected by serious and other adverse events and a set of serious-event terms. They offer descriptive information, but the record does not report a comparator, causal attribution, or enough detail to interpret event timing and recurrence. Those summaries cannot establish comparative safety or explain the unpopulated deaths field.
In general, a trial record can document a planned clinical question even when it does not yield an analyzed answer. In this case, the planned primary question is identifiable, but its result is not. The registry record is therefore informative about design and reporting status, while remaining insufficient for a quantitative efficacy conclusion.
13. Why This Trial Matters Statistically
This trial matters statistically because it illustrates the difference between a registered endpoint and an analyzed endpoint. Tumor response at 6 months was specified as the primary outcome, but the record states that no patients were analyzed for it. Without an outcome estimate, statistical tools such as confidence intervals and hypothesis tests cannot quantify the primary result. The endpoint name alone is not evidence of an outcome.
It also illustrates how design determines the kind of inference a study can support. The record describes a single group, not a randomized comparison. A single-group design can be used to describe outcomes, but it cannot provide a direct randomized contrast against a control group. Here, even that within-group primary outcome description is unavailable because no patients were analyzed.
The distinction between enrollment and analysis is important. Enrollment is recorded as 6, yet the primary endpoint has no analyzed patients. Those statements are not interchangeable: a participant can be enrolled without contributing an evaluable outcome to a particular analysis. The registry attributes this situation to early termination and an inadequate number of patients, but does not provide further detail on the flow from enrollment to analysis.
Finally, the adverse-event summaries demonstrate why descriptive counts need context. They are not a comparative analysis, do not establish causation, and lack reported details about timing and event attribution. Keeping those summaries separate from the primary efficacy question prevents safety listings from being mistaken for evidence about tumor response.
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.
The most direct limitation is that the primary tumor-response outcome has no analyzed patients. The registry attributes this to early termination and an inadequate number of patients. As a result, the record does not provide a response estimate, uncertainty interval, or test result. It is not possible to determine from this record whether the planned endpoint could have been assessed under a different analysis approach.
The single-group design provides no concurrent control group and no randomized comparison. The registry lists allocation as NA and masking as NONE. Further details about outcome assessment procedures are not reported, so the potential role of assessor masking cannot be characterized beyond the listed masking status.
The tumor-response definition and assessment rules are not reported in the registry record. The record also does not describe the analysis population, missing-outcome procedures, multiplicity handling, or statistical analysis plan. Without these details, the endpoint cannot be reproduced or evaluated for susceptibility to analytic choices.
Although adverse-event summaries are listed, the record does not report event timing, follow-up duration, attribution, recurrence, or a comparator. Death appears among the serious-event terms, but the deaths field is not populated and the relationship between these entries is not explained. The secondary outcomes are listed without reported analyses or results.
Finally, the registry identifies termination but does not report further detail about its reason or the enrollment process. These limitations constrain interpretation to the study's recorded design and reporting status; they do not justify assumptions about unreported procedures or outcomes.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Photodynamic Therapy Using HPPH in Treating Patients With Advanced Non-Small Cell Lung Cancer That Blocks the Air Passages — NCT00528775.
- Registry record last updated 2014-06-10; status last verified 2014-05.
- Results first posted 2014-06-10.
- 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 describes a phase II, single-group study of HPPH photodynamic therapy for advanced obstructing endobronchial lung cancer. Enrollment was 6, and the study status is TERMINATED. The listed regimen combined HPPH with endoscopic light treatment. Tumor response at 6 months was the primary outcome, but the record states that no patients were analyzed because the study ended early and the number of patients was inadequate.
Four secondary outcomes concerned symptom palliation, HPPH concentration in tumor, STAT3 cross-links, and inflammation and apoptosis. The registry lists adverse-event summaries for the HPPH group, but does not provide a control comparison or primary efficacy analysis. Consequently, the record documents the intended clinical question and the study's reporting limitations, not an analyzed estimate of tumor response.