A biologic drug is a medication that’s created from human or animal proteins. Biologic drugs used to treat autoimmune diseases, such as plaque psoriasis, work by interacting with the body’s immune system. They do this in targeted ways to reduce inflammation and other symptoms of an overactive immune system.
Because they interact with very specific immune system cells and proteins, biologics are thought to have fewer side effects compared to drugs that affect a wider range of body systems, as many drugs do.
When used to treat psoriasis, biologic drugs are generally used for people with moderate to severe plaque psoriasis who don’t respond to other treatments (such as topical therapy).