This guidance provides recommendations to holders of approved new drug applications (NDAs), abbreviated new drug applications (ANDAs), new animal drug applications (NADAs), and abbreviated new animal drug applications (ANADAs) and holders of drug master files (DMFs) and veterinary master files (VMFs) who want to make a change to the drug substance manufacturing process during the drug product application’s postapproval period.
It does not address holders of biologics license applications (BLAs) or holders of any master files cross referenced in BLAs.


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Postapproval Changes to Drug Substances Guidance for Industry