Review of Drugs Approved via the 505(b)(2) Pathway: Uncovering Drug Development Trends and Regulatory Requirements
Bibliographic record
Abstract
A 505(b)(2) application is a type of US new drug application (NDA) that contains full reports of investigations of safety and effectiveness, but where at least some of the information required for approval comes from studies not conducted by or for the applicant and for which the applicant has not obtained a right of reference. Most 505(b)(2) applications consist of changes to a previously approved drug product (ie, a new dosage form, new routes of administration, etc). Sponsors often face challenges determining the studies to be conducted to support approval via 505(b)(2) pathway. This 5-year (2012-2016) retrospective analysis reviewed approved 505(b)(2) NDAs available on the FDA website, to determine the nature of studies (preclinical, clinical pharmacology, and efficacy/safety) conducted for various types of submissions and to better understand the trends in terms of regulatory requirements. The database consisted of 226 NDAs. One hundred twelve of those 226 had complete FDA review information, with the following FDA submission classes being more prevalent: type 3, new dosage form; type 4, new combination; and type 5, new formulation or new manufacturer. Therefore, only these 112 NDAs were further examined as they could show trends in terms of the studies conducted for various types of applications. Based on the investigation of NDA review documents, coupled with guidance documents, decision trees for studies to be conducted have been developed, which may serve as a guide of recommendations for a successful 505(b)(2) development program and NDA submission.
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 | 0.073 | 0.156 |
| Meta-epidemiology (narrow) | 0.000 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.020 | 0.017 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.005 | 0.004 |
| Open science | 0.002 | 0.002 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.003 | 0.002 |
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".