IL-17 inhibitors represent a specialized category of targeted therapies designed to address certain inflammatory conditions by modulating the body’s immune system. These medications focus on specific components of the immune response rather than broadly suppressing it. Their development marks a significant advancement in treating chronic inflammatory diseases, offering a more precise approach to managing symptoms and disease progression.
Understanding IL-17 and Its Role
Interleukin-17 (IL-17) is a type of cytokine, which are small proteins that act as messengers in the immune system. These cytokines play a role in coordinating the body’s defense mechanisms and inflammation. IL-17 initiates a potent inflammatory response.
While IL-17 is important for fighting off infections, particularly against extracellular bacteria and fungi, an overactive or dysregulated IL-17 pathway can contribute to chronic inflammatory diseases. When its activity is not properly controlled, it can lead to persistent inflammation and tissue damage.
Conditions Treated by IL-17 Inhibitors
IL-17 inhibitors are approved for treating several chronic inflammatory conditions where an overactive IL-17 pathway contributes to the disease’s progression. These conditions include moderate to severe plaque psoriasis, psoriatic arthritis, and ankylosing spondylitis. These targeted therapies are considered for individuals who have not responded adequately to conventional treatments.
Psoriasis, particularly moderate to severe plaque psoriasis, is characterized by thick, red, scaly patches on the skin. IL-17 drives the inflammation in psoriasis. Inhibiting IL-17 can lead to reductions in skin lesions, itching, and pain.
Psoriatic arthritis (PsA) is a form of arthritis that affects some people with psoriasis, causing joint pain, swelling, and stiffness. IL-17 contributes to joint inflammation and damage in PsA. Medications that block IL-17 have shown improvement in joint inflammation and pain, as well as in skin manifestations associated with PsA.
Ankylosing spondylitis (AS) is a type of inflammatory arthritis that primarily affects the spine, leading to pain and stiffness. IL-17 inhibitors have demonstrated improvement in the signs and symptoms of AS, including reduced pain and stiffness.
How IL-17 Inhibitors Work
IL-17 inhibitors are a type of biologic medication that targets the inflammatory pathway involving Interleukin-17. These medications are monoclonal antibodies, which are engineered proteins designed to bind to specific molecules in the body. In this case, they either bind to the IL-17A cytokine itself or to its receptor on the surface of cells.
By blocking IL-17A from binding to its receptor, these inhibitors disrupt the inflammatory cascade that IL-17 would normally trigger. This action reduces the signals that lead to inflammation, thereby alleviating disease symptoms. This targeted approach reduces inflammation and its associated symptoms without broadly suppressing the immune system. Effectiveness is noticeable within a few weeks.
Common IL-17 Inhibitors and Potential Side Effects
Several IL-17 inhibitor medications are available, commonly administered via subcutaneous injection. Secukinumab (Cosentyx) is a monoclonal antibody that blocks the binding of IL-17A to its receptor. It is approved for moderate to severe plaque psoriasis, psoriatic arthritis, and ankylosing spondylitis.
Ixekizumab (Taltz) is another monoclonal antibody that shares a similar mechanism of action with secukinumab, also blocking IL-17A. Ixekizumab is approved for plaque psoriasis, psoriatic arthritis, and ankylosing spondylitis.
Brodalumab (Siliq) works differently by blocking the IL-17RA receptor. Brodalumab is approved for moderate to severe plaque psoriasis.
While these medications are effective, they can have potential side effects. A common concern is an increased risk of infections, including upper respiratory tract infections and fungal infections like candidiasis, due to their effect on the immune system. Injection site reactions, such as redness, pain, or swelling, are also commonly reported.
Other potential side effects include diarrhea, headache, and nausea. Patients are screened for tuberculosis before starting treatment, as these medications can reactivate latent infections. It is important for individuals to discuss any concerns or adverse reactions with their healthcare provider to manage treatment effectively.