The Role Of Biologics In Psoriasis
Psoriasis is a common, non-contagious, autoimmune disease that affects more than 125 million people worldwide. It is not just a cosmetic problem and affects the overall everyday lives of patients. Close to 3% of the world’s population suffers from psoriasis. Psoriasis, which is not contagious, can begin at any age, including in childhood, but mainly affects adults.
Psoriatic symptoms start appearing when a combination of environmental and genetic factors disrupt the normal lifecycle of skin cells. The skin cells usually grow within the deep layers of the skin and move to the surface once in 30 days. In psoriasis, the immune system mistakenly starts attacking healthy skin cells, accelerating the process and causing the dead skin cells to rapidly build up on the skin’s surface, giving it a raised, scaly, itchy, dry, and red appearance.
Psoriasis is associated with an increased risk of psoriatic arthritis, lymphomas, cardiovascular disease, Crohn's disease, and depression. Psoriatic arthritis affects up to 30% of individuals with psoriasis.
Psoriasis is categorized as mild when plaques cover less than 5 percent of the body’s surface area (BSA) and moderate when they cover 5-10 percent of the BSA. When the disease affects more than 10 percent of the body, it’s considered severe.
The standard tool used for calculating the severity of psoriasis is known as Psoriasis Area and Severity Index (PASI). It measures how much of the body surface area is affected by psoriasis – taking into account the expanse of raised red patches, the hardness and scaling of plaques.
The most widely used treatment options for mild to moderate psoriasis are topical treatments like corticosteroids, vitamin D analogues and phototherapy (light therapy). Systemics are conventionally prescribed for moderate to severe cases and in psoriatic arthritis. Unlike topical or phototherapy, which target only the external surface of the skin, systemics work all throughout the body. However, systemics cannot clear the disease fully and might have serious adverse effects on the liver and blood.
Biologic drugs are considered the most effective treatment options for severe psoriasis and psoriatic arthritis. Biologics may be used alone or in combination with other options like phototherapy and topicals. They are considered as viable treatment options even for patients who don’t respond to or experience side effects of other treatment regimes. Treatment with biologics should be compliant and continuous to maintain results.
Biologic drugs are protein-based drugs that target those specific parts of the immune system, that are responsible for triggering the disease, and are administered through injections or intravenous (IV) infusion.
In case of psoriasis, biologics utilize molecules that are designed to block specific molecular steps, vital to the pathogenesis of psoriasis. The biologics used to treat psoriatic disease block the action of a specific type of immune cell, called a T cell or block proteins like tumor necrosis factor-alpha (TNF-alpha), interleukin (IL) 17-A, or interleukins 12 and 23. These proteins play a role in developing psoriasis and psoriatic arthritis.
Biologic drugs involve complex immunology and understanding of how to use them. Any potent and effective therapy requires expert care in using the drug. Dermatologists treating psoriasis with biologics should be well versed in this. They should also know how to optimise therapy with the newer highly effective drugs like IL17 blockers.
Recent global studies have revealed that innovative biologic molecules, that work as inhibitors potentially modify the course of psoriasis. These molecules work by blocking a cytokine, or protein, called interleukins which are involved in inflammatory and immune responses.
Biologics present a huge step forward in the treatment of psoriasis by helping patients and doctors better manage the disease. Achieving clear skin and living a normal life is now a real possibility for psoriasis patients.