Clobetasol brazilian pilot study: the vasoconstrictor assay over time
Bibliographic record
Abstract
The vasoconstrictor assay (VCA) has been internationally recognized as a reliable method to evaluate the bioequivalence of topical corticosteroids. The FDA has recommended its use since 1995 and ANVISA began to require this assay in 2022 (RDC no. 742/22). The objective of this study was to compare results from two VCA pilot studies, using two Konika Minolta® instruments and two different estimation methods. The Emax and ED50 parameters were obtained using a nonlinear mixed effect model and least squares fit using a Gauss-Newton algorithm. Regardless of the equipment or the fitting methods, similar Emax and ED50 were obtained. However, both parameters were different when comparing the assays performed from different batches of the same reference list drug (RLD) and procedures from the different guides. Added to this, the tests were carried out at different times and in different seasons. In the VCA pilot study, estimating the ED50 is essential to determine the D1 and D2 (shorter and longer dose duration reference standard calibrator) to be used in the pivotal bioequivalence study. The diversity of the Brazilian population and the lack of experience to perform the procedure represent major challenges for the implementation of this test.
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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 | 0.004 | 0.004 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.003 | 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".