Now is that for new drugs never developed before?

Now is that for new drugs never developed before?  What is the time for existing drugs that have been on the market, ie  Oxycodone, which is nothing new, and has been used for the past three decades as the main pain killer ingredient.  I can't imagine a full blown P3 that will take 2-3 years for two ingredients that has been avail. for a long long time.