The barrage of biological patent expirations that will precipitate until 2020 has the current year as one of the main protagonists. Up to four molecules will lose protection this year, so the appearance of their respective biosimilars will not be long in coming. The affected drugs will be Enbrel (etanercept), Novomix, (insulin aspart), Copaxone (glatiramer acetate) and Neulasta (pegfilgrastim), from the companies Pfizer, Novo Nordisk, Teva and Amgen, respectively.