13. Cosentyx
Typical cost for a 30-day supply: $29,300
Treats: Plaque psoriasis; psoriatic arthritis; ankylosing spondylitis, a form of arthritis that affects the spine and large joints
Approved in early 2015, Cosentyx treats moderate to severe plaque psoriasis by targeting the protein thought to cause it. Eight in 10 people who used the drug saw their skin clear up significantly.
