Cuprimine, a drug that's already been the subject of congressional drug price hearings, has been around since the 1950s. It's currently owned by Valeant, and in the past few years, its price has shot up. It's used to treat Wilson Disease, a rare, inherited disease that causes copper to build up in the body. The drug works to get that copper out of a person's system. Like others in this list, the drug is also included on the World Health Organization's list of essential medicines. The price is for 120 capsules, taken after every meal.