Amgen filed litigation in a Colorado federal district court late Friday (March 22) against Colorado’s prescription drug affordability board (PDAB), saying the board’s actions are “unconstitutional.” The board is currently considering whether to set an upper payment limit on Amgen’s drug Enbrel, used to treat various forms of arthritis and psoriasis, after the board declared the drug “unaffordable” in February. “Amgen believes the Board’s actions are unconstitutional and we are confident the Court will give careful consideration to the issue...