Here's a look at what patents do and why they matter:HOW DO DRUG PATENTS WORK?Patents reward innovation by preventing competitors from simply copying a company's discovery and launching a rival product.
In the US, patents on medicines typically last 20 years from when they are filed, which is usually done as soon as a drugmaker thinks it has an important or lucrative drug.Because it often takes a decade to get a drug approved, companies typically end up with about a dozen years of competition-free sales.