Priciest Drugs in the World: This is a list of the world's most expensive pharmaceutical drugs. Hopefully nobody you know will ever contract diseases that require these pricey drugs because the medication is the most expensive in the world. The drugs on this list are biotech drugs and used to treat rare diseases. It goes to show that sometimes it doesn't pay to be unique. Or, actually, it does, but not the way you'd like. The data for this most expensive drugs in the world list is from www.forbes.com/2010/02/19/expensive-drugs-cost-business-healthcare-rare-diseases_slide_2.html. Thought I'd share the information with you all.