FDA novel drug approvals and market withdrawals by therapeutic modality, 1990-2025

A year-by-year classification of 1,246 novel active substances approved in the United States between 1990 and 2025 into seven therapeutic modalities (small molecule, antibody, antibody-drug conjugate, peptide, protein/enzyme, oligonucleotide, other), with a companion curated set of 45 US market withdrawals classified on the same scheme and keyed on year of withdrawal. Built from a frozen Drugs@FDA snapshot, cross-referenced against ChEMBL, and reconciled against FDA's published novel drug approval counts for 2006-2025 (r = 0.9992). Read before use. The two series are not of equal evidential quality. Approvals for 2006-2025 are validated against FDA's published counts. Approvals for 1990-2005 carry lower confidence, because the source database purges withdrawn products inconsistently; every row carries a confidence column recording this. The withdrawals series is hand-curated and its completeness is not benchmarkable - no machine-readable registry of US market withdrawals exists, and four candidate sources were tested and rejected. Includes the reproduction notebook, the frozen classification pipeline source, full methodology and known-issues documentation, validation tables and the exclusion log.