Glossary
Category 1 of the interim 503A bulks list holds substances that are under review and for which the FDA has not identified safety concerns. Pharmacies may compound with a Category 1 substance while that review continues.
Category 1 is a permission during review rather than an approval, and it can end. A molecule sitting in it today holds a real and lawful position, and holds it provisionally; this index therefore dates every such status rather than stating it flatly.