Ever since the signing of the US healthcare reform legislation, the Patient Protection and Affordable Care Act (PPAC), speculation as to what a US FDA biosimilar programme might look like has been rife. Now the FDA has published guidance documents on biosimilar product development, which has been described by Dr Janet Woodcock, MD, Director of the FDA’s Center for Drug Evaluation and Research, as “an innovative approach to supporting the development of biosimilars at every step of the process.” Nevertheless, these initial guidelines are rather general in nature, so the looming question remains as to what extent the US biosimilar pathway will represent a viable route to market.