ABSTRACT
This study examined the 18-month postlaunch behavior of 3,646 US physicians to determine how prelaunch company prescribing loyalty affects subsequent prescribing levels–a new product's prescribing volume and the incremental prescribing volume of other drugs from the company launching the new product. Prelaunch company prescribing loyalty is particularly important for understanding first-in-class drugs, less so for new drugs in existing drug categories. This loyalty is also associated with an increased prescribing volume for other drugs from the pharmaceutical company, regardless of a physician's willingness to prescribe the newly launched drug from that company.
