Despite the passage of a 2010 law addressing such medicines, the Food and Drug Administration’s (FDA) approval this year of the first biosimilar has prompted a flurry of regulatory activity aimed at filling gaps left by the statute. For a helpful primer on the issue, see a recent Health Affairs Health Policy Brief. This post will address key concerns raised by recent FDA guidance, as well as other widely anticipated but yet-to-be released regulatory activity, such as the pivotal interchangeability standard....