FDAnews Device Daily Bulletin

Manufacturers of transdermal patches should minimize the amount of residual drug substance in the patch as much as possible to avoid patient and environmental safety risks, according to a new European Medicines Agency (EMA) draft guideline. An excess of drug substances in transdermal patches is common, because the excess is necessary to deliver the drug at a clinically effective rate over time, the EMA notes. However, the risk of crystallization during storage could adversely affect the product’s quality and efficacy.
International Medical Device Regulatory Monitor