Among pharmaceutical industry insiders, it is known as the patent cliff.
Over the next two years, patents for many blockbuster brand-name drugs sold in Japan are set to expire. Astellas Pharma’s patent on Lipitor, a cholesterol-lowering drug licensed from Pfizer, runs out in 2011, while that of AstraZeneca’s Arimidex, for breast cancer, is up the following year.
