Low-dose metronomic topotecan and pazopanib in children with recurrent or refractory solid tumors: A C17 Canadian phase I trial (TOPAZ).
Bibliographic record
Abstract
10020 Background: Low-dose metronomic topotecan (mTP) represents a novel approach to chemotherapy delivery which, in preclinical models, may work synergistically with pazopanib (PZ) in targeting angiogenesis. This study was designed to determine the recommended phase 2 dose (RP2D) of mTP/PZ in pediatric patients with solid tumors, while describing the safety and toxicity of this regimen. Methods: A phase I dose-escalation, pharmacokinetic (PK) and pharmacodynamic (PD) study of mTP/PZ was conducted at ten sites across Canada, enrolling pediatric patients aged 2-21 years with relapsed/refractory solid tumors. Patients were treated with oral mTP and PZ suspension daily without interruption in 28-day cycles, with dose escalation in accordance with the rolling-six design. Five dose levels (0.12/125, 0.16/125, 0.22/125, 0.22/160, and 0.3/160 mg/m2/day of mTP/PZ) were evaluated. PK studies were performed on day 1 and at steady state, and PD studies included circulating angiogenic factors VEGFR1, VEGFR2, VEGF, endoglin and placental growth factor. Results: Thirty patients (pts) were enrolled, of whom 26 were evaluable for dose-limiting toxicity (DLT), with median age 12 years (3-20). The most common diagnoses included osteosarcoma (8), neuroblastoma (NB, 7), Ewing sarcoma/PNET (4), and rhabdomyosarcoma (4). The most common grade 3/4 adverse events (AEs) related to protocol therapy were neutropenia (18%), thrombocytopenia (11%), lymphocytopenia (11%), AST elevation (11%), and lipase elevation (11%). Only 2 cycle-1 DLTs were observed on study, both at the 0.3/160 mg/m2 mTP/PZ dose level (2/5 pts) comprising persistent grade 3 thrombocytopenia and grade 3 ALT elevation. No AEs experienced beyond cycle-1 required treatment discontinuation. Best response was stable disease in 10/25 pts (40%) for a median duration of 6.4 months (1.7-45.1). One patient with refractory NB achieved stable disease for 45 months and continued on mTP/PZ via compassionate access after study closure. PK and PD results are pending at this time. Conclusions: The combination of oral mTP and PZ is safe and tolerable in pediatric patients with solid tumors, with a RP2D of mTP 0.22 mg/m2/day and PZ suspension 160 mg/m2/day. Ten patients achieved stable disease for a median of 6 months. The lack of objective responses suggests that this combination is likely of limited benefit for relapsed disease, but may play a role as maintenance therapy. Clinical trial information: NCT02303028.
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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 | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.001 | 0.002 |
| Insufficient payload (model declined to judge) | 0.002 | 0.000 |
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".