A review of 565 phase II trial abstracts from ASCO 2005: Design characteristics of contemporary trials evaluating cytotoxic versus non-cytotoxic regimens
Bibliographic record
Abstract
6569 Background: New phase II trial designs have been proposed to accommodate the non-cytotoxic nature of molecularly targeted agents. In particular, the use of alternative endpoints and controls has been suggested. The objectives of this survey are to review the designs of contemporary phase II trials, to compare trials of cytotoxic versus non-cytotoxic regimens, and to identify predictors of acceptance for presentation. Methods: Abstracts of phase II trials of systemic anticancer therapy published in the 2005 ASCO Proceedings were hand searched. The trial context, type of intervention, trial design, endpoints, and completeness of reporting were assessed. Results: Our search yielded 565 abstracts: 72% were multi-center, 44% North American, 25% clearly identified as industry-sponsored, the median number of patients was 44 (range 8–346). Only 83% explicitly reported the study phase, 29% the primary endpoint, 11% the number of stages, and 5% the statistical design. For design properties, 16% used multiple arms and 6% used enrichment. Of trials reporting the primary endpoint, 48% used radiological or marker response and 22% time-to-event endpoints. The median number of endpoints was 4 (range 1–8). Non- cytotoxic regimens, which included targeted agents, hormone- or immunotherapy, constituted 22% of the trials reviewed, purely cytotoxic regimens 60%, the remaining 18% contained combinations of both. Trials of non-cytotoxic and combination regimens were more likely to report the primary endpoint (p=0.02), use time-to-event endpoints (p=0.006), have multiple arms, use enrichment, be conducted in North America, be industry-sponsored, and be accepted for oral or poster presentation (all p<0.001). Other predictors of publication type in multivariate analysis were multi-centricity, higher number of patients, industry involvement, and being conducted in North America (all p<0.05). Conclusions: Design properties of contemporary phase II trials of non-cytotoxic agents differ from trials of cytotoxic chemotherapy, and are more likely to be accepted for presentation at ASCO. Proposed new trial designs start to be more widely adopted. Most abstracts incompletely report design properties. No significant financial relationships to disclose.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.076 | 0.210 |
| Meta-epidemiology (narrow) | 0.002 | 0.002 |
| Meta-epidemiology (broad) | 0.008 | 0.007 |
| Bibliometrics | 0.019 | 0.027 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.004 | 0.003 |
| Open science | 0.002 | 0.002 |
| Research integrity | 0.002 | 0.001 |
| Insufficient payload (model declined to judge) | 0.007 | 0.001 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".