Approvals and Timing of New Formulations of Novel Drugs Approved by the US Food and Drug Administration Between 1995 and 2010 and Followed Through 2021

New formulations of prescription drugs can improve convenience and tolerability for patients, but they also constitute manufacturer strategies to extend brand-name drug market exclusivity periods. We examined whether new formulations of brand-name novel drugs were associated with novel drugs’ sales and/or therapeutic value, as well as characterized first new formulations’ approval timing relative to the novel drug’s generic approval. We found that manufacturers are several times more likely to secure Food and Drug Administration approval for a new formulation for existing drugs that have reached blockbuster status. (Blockbuster drugs are the most profitable drugs with more than $1 billion in annual sales, but are not necessarily the most innovative or clinically meaningful drugs.) Manufacturers also dramatically reduced pursuing approval for new formulations once their drugs began to face generic competition. In contrast, companies did not develop new formulations for drugs that were considered the most therapeutically valuable, innovative, or clinically useful. Thus, while the modified formulations may not be innovative or clinically meaningful themselves, drug manufacturers frequently do not alter drugs that are particularly valuable and innovative to begin with. Our study shows that drugs’ revenue, as opposed to patient benefit, is the clear driver for reformulating drugs