Switch patterns before and after patent expiry of omeprazole: a case study in The Netherlands

Summary Background An increase of therapeutic substitution after patent expiry might have a negative effect on cost‐savings generated with newly introduced generic drugs. To evaluate influences of patent expiry on therapeutic substitution, switch behaviour before and after patent expiry was investigated. Aim To describe proton pump inhibitor use and investigate substitution patterns from omeprazole before and after patent expiry. Methods Data were obtained from the InterAction DataBase. Proportional proton‐pump inhibitor use was identified per quarter during the study period 2000–2003. For the... Mehr ...