The 10 most expensive drugs in the US

Viekira Pak is a hepatitis C drug meant to cure those with the virus. Hepatitis C is a disease that's transmitted by blood. Once infected, most don't have immediate symptoms, but left untreated it can lead to cirrhosis, liver failure, and liver cancer. It affects between 130 million and 150 million people worldwide.

The drug Firazyr is used to treat a rare condition called hereditary angioedema, or HAE, a blood disorder that causes episodic swelling. Firazyr is an injection that can be used to treat these attacks. This price is for three syringes worth of the drug.

Cuprimine, a drug that's already been the subject of congressional hearings on drug prices, 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; one is taken after every meal.

When it was approved, Vertex's drug made headlines for costing $259,000 a year. It treats a particular type of cystic fibrosis and is taken twice a day. Cystic fibrosis is a rare inherited disease in which a thick mucus builds up in the lungs and other key organs.

Olysio is another drug to treat hepatitis C. It's used in combination with another drug, called sofosbuvir, to treat the disease. This price is for two bottles of 28 capsules.

HP Acthar gel, a drug that's used to treat multiple sclerosis, infantile spasms, rheumatoid arthritis and a few other conditions, has in the past been called out for its high price tag. The drug was originally approved in the 1950s, and is currently owned by Mallinckrodt Pharmaceuticals. This price is for two vials of the drug.

Daklinza is another hepatitis C cure. It's used on its own to treat people with genotype 3 hepatitis C along with sofosbuvir, another hepatitis C drug.

Cinryze is another drug used to treat to treat HAE. The injections, taken twice a week, are used to prevent the swelling attacks that HAE causes.

Gilead's second hepatitis C cure was approved in 2014. The combination drug actually is cheaper than sofosbuvir on its own for a full course of treatment, according to GoodRx's fair price analysis.

Sovaldi, the first of a new set of hepatitis C cures that hit the market in 2013, came under a lot of fire for costing $1,000 a pill, adding up to $84,000 for a 12-week course of treatment. According to GoodRx, the most, without insurance, that a person should pay is $81,000 for the full treatment.