1. Trial at a Glance
The ELVIS study was a phase II study of oxaliplatin and Navelbine for second-line treatment of advanced NSCLC. The registry describes the study as a treatment trial with a single-group design.
| Feature | ELVIS |
|---|---|
| Phase | Phase 2 |
| Population | Previously Treated Metastatic Non-Small Cell Lung Cancer |
| Enrollment | 40 |
| Allocation | Non-randomized |
| Design model | Single group |
| Masking | None |
| Primary purpose | Treatment |
| Intervention | Oxaliplatin (drug) |
| Lead sponsor | Integrated Community Oncology Network |
| ClinicalTrials.gov | NCT00238849 |
2. Clinical Question
Population
Patients with previously treated metastatic non-small cell lung cancer.
Intervention
Oxaliplatin (drug).
Comparator
No comparator arm was registered.
Primary question
The registry identified efficacy as the primary endpoint.
3. Trial Design
The ELVIS trial used a non-randomized, single-group phase II design. Because there was no randomized comparator, statistical interpretation focuses on the assessment of outcomes within the treated study population rather than a direct treatment-effect comparison.
| Design element | Description |
|---|---|
| Allocation | NON_RANDOMIZED |
| Design model | SINGLE_GROUP |
| Masking | NONE |
| Enrollment | 40 |
4. Endpoints
| Endpoint | Registry definition |
|---|---|
| Efficacy | Primary endpoint |
The ClinicalTrials.gov record identifies efficacy as the registered primary endpoint. Additional endpoint definitions and time frames are not reported in the registry information reviewed here.
5. Planned Analysis
The registry does not contain posted statistical analyses or efficacy results for ELVIS.
For a single-group phase II efficacy study, statistical analysis would typically summarize observed clinical outcomes and estimate uncertainty around those observations. Depending on the endpoint definition, methods could include response proportions with confidence intervals, time-to-event summaries using Kaplan-Meier estimation, or descriptive safety summaries.
Without randomization or a concurrent comparator, observed outcomes cannot by themselves establish whether differences are caused by the intervention rather than patient characteristics, disease history, selection effects, or other factors.
6. Statistical Methodology
Single-group phase II analysis
Single-group studies are commonly designed to evaluate whether a treatment demonstrates sufficient activity to justify additional investigation. The statistical question is usually framed around whether observed activity meets a predefined threshold rather than whether one treatment is superior to another randomized treatment.
Confidence intervals
Confidence intervals provide information about uncertainty around estimated quantities. They are particularly important in smaller phase II studies because estimates may be imprecise when based on limited numbers of patients.
Time-to-event analysis
If efficacy outcomes involve survival or progression times, Kaplan-Meier methods are commonly used because they account for patients whose event times are not observed during follow-up.
7. Statistical Methods Explained
Why does a single-group study not provide a treatment comparison?
A single-group design measures what happened after treatment exposure but does not include a randomized control condition. A difference from historical expectations may reflect treatment effects, but it may also reflect differences in patient populations or study conduct.
Why are confidence intervals important?
A point estimate alone does not describe precision. Confidence intervals show the range of values compatible with the observed data under the statistical model.
Why is sample size important in phase II trials?
With enrollment of 40 participants, estimates may have substantial uncertainty. Smaller studies are often intended for preliminary evaluation rather than definitive confirmation.
Why is randomization important?
Randomization helps balance known and unknown prognostic factors between groups, allowing stronger causal interpretation of treatment differences.
What does an efficacy endpoint measure?
An efficacy endpoint defines the outcome used to evaluate whether a treatment demonstrates activity or benefit according to the study objectives.
8. Limitations
- No randomized comparator: the study design does not allow a direct randomized comparison between treatments.
- Single-group interpretation: observed outcomes cannot separate treatment effects from other influences.
- Sample size: enrollment was 40, limiting precision of estimates.
- Limited registry reporting: posted statistical analyses and results are not available in the ClinicalTrials.gov record reviewed.
9. Why This Trial Matters Statistically
ELVIS illustrates the statistical role of early-phase clinical trials. Phase II studies often serve as an intermediate step between initial safety evaluation and larger comparative trials.
| Concept | How it appears in ELVIS |
|---|---|
| Phase II design | Evaluation of treatment activity |
| Single-group design | Outcomes measured without randomized comparator |
| Non-randomization | Limits causal comparison |
| Efficacy endpoint | Primary registry endpoint |