Evidence of ‘Evergreening’ in Secondary Patenting of Blockbuster Drugs
Secondary patents associated with blockbuster drugs are granted for follow-on innovations relating to the active pharmaceutical ingredient (‘API’) of the drug.
Our analysis of all secondary patents for 13 top-selling drugs in Australia shows that, while the majority of follow-on innovations are made by entities other than the originator of the drug, the innovations with the highest private value are undertaken by the drug’s originator and concern a delivery mechanism or an alternative formulation for the API.
Since that is the type of follow-on innovation most commonly undertaken by drug originators, and considered most likely to result in a de facto extension of marketplace monopoly over the drug, we see in these findings evidence that the originators of blockbuster drugs engage in secondary patenting that has an ‘evergreening’ effect.