Photograph of a young man suffering from severe ankylosing spondylitis

Plaque psoriasis is an irritating, often painful immune-mediated disorder that affects up to 3 million Americans at any given time. While medical science appears no closer to finding a bonafide cure, there are some effective treatments on the market. One of the latest treatments, a drug called Cosentyx produced by Swiss pharmaceutical company Novartis, was promising enough to gain FDA approval in January.

However, based on the latest clinical trials, Novartis is confident that Cosentyx may be able to treat more than just plaque psoriasis.

Psoriasis often accompanies related conditions, including psoriatic arthritis and ankylosing spondylitis. Earlier studies had shown that Cosentyx demonstrated one-year efficacy for ankylosing spondylitis, and the latest clinical data indicates that it’s effective in treating psoriatic arthritis as well.

With demonstrated potential to treat three related diseases, Novartis believes Cosentyx has a particularly high sales ceiling. While industry analysts originally predicted the drug could sell in the neighborhood of $1.8 billion by 2020, Novartis believes it could sell double that, or more – as much as $5 billion.

According to Novartis, the market for drugs to treat these diseases is in the $12 billion range, and growing quickly.

While most drugs that treat plaque psoriasis have a tendency to lose potency over time, Cosentyx is something of a miracle: The once-monthly injectable has proved to be effective for two years and beyond, a marked improvement over other treatments like steroids. Cosentyx is the first in a new class of IL-17A inhibitors, which target a protein linked to inflammation.

Psoriasis and its related diseases are complicated, and doctors still aren’t 100% sure what causes them. It’s believed to be genetic, but it’s not solely a skin disorder, nor is it completely autoimmune, either. Besides itchy and unsightly collections of skin cells that build up, plaque psoriasis is associated with an increased risk of certain cancers, cardiovascular disease and other maladies.