In recent decades, extensive emphasis has been given on developing nanopharmaceutical products for improving the therapeutic performance of drugs, resulting in an increasing number of product approvals by drug regulatory agencies. Although nanopharmaceuticals are subjected to the same regulatory pathways as conventional pharmaceutical products, their biopharmaceutical characteristics at the nanoscale make them vulnerable to high variability in quality. Positive effects on drug quality assurance have resulted from adopting systematic quality-by-design (QbD) principles, boosting pharmaceutical manufacturing with improvements in the quality, safety, and efficacy of drugs.