Tremfya, known by its generic name guselkumab, is a type of biologic medication. Biologics are complex drugs made from living cells, distinguishing them from traditional chemically synthesized medicines. This prescription medicine is used to address certain chronic inflammatory conditions in adults. Tremfya works by targeting a specific component of the immune system to help reduce inflammation.
Understanding IL-23 and How Tremfya Works
Interleukin-23 (IL-23) is a protein that plays a role in the body’s immune responses and inflammation. It is produced by various immune cells, including macrophages and dendritic cells, in response to inflammatory triggers or microbial invasions. IL-23 is composed of two parts: a p19 subunit and a p40 subunit.
This protein is involved in driving the differentiation and activation of immune cells called Th17 cells. Th17 cells, once activated by IL-23, produce inflammatory signaling molecules, such as IL-17A, IL-17F, and IL-22, which contribute to ongoing inflammation in various tissues. Elevated levels of IL-23 are associated with several autoimmune diseases.
Tremfya is a monoclonal antibody designed to selectively target and bind to the p19 subunit of IL-23. By blocking this subunit, Tremfya prevents IL-23 from interacting with its receptor on immune cells. This action disrupts the signaling pathway that leads to the activation and proliferation of Th17 cells and the release of their pro-inflammatory cytokines. This selective blockade helps to reduce the underlying inflammation and symptoms associated with certain chronic inflammatory diseases.
Conditions Treated by Tremfya
Tremfya is indicated for individuals with moderate to severe plaque psoriasis who may benefit from systemic therapies or phototherapy. Plaque psoriasis is a chronic skin condition characterized by red or dark-colored, scaly patches on the skin, which can also affect the scalp.
The medication is also approved for adults living with active psoriatic arthritis. Psoriatic arthritis is a chronic, immune-mediated inflammatory disease that causes pain, stiffness, and swelling in and around the joints. It can also lead to enthesitis, which is pain where tendons and ligaments meet bone, and dactylitis, an inflammation in the fingers and toes that can result in a swollen, sausage-like appearance.
Tremfya is considered for use in patients when other systemic treatments or light therapy have not been effective in managing their conditions. Some patients with plaque psoriasis may also develop psoriatic arthritis.
Administering Tremfya
Tremfya is administered as an injection under the skin. The medication comes as a liquid solution in either a prefilled syringe or a patient-controlled auto-injector device. This allows for administration by a healthcare professional or, after appropriate training, by the patient or caregiver at home.
The dosing schedule for Tremfya involves two initial doses given at week 0 and week 4. Following these starter doses, maintenance injections are given every 8 weeks. The medication should be stored in a refrigerator.
Potential Side Effects and Safety Considerations
Like all medications, Tremfya can cause side effects. Common side effects include upper respiratory infections, such as colds, headaches, and injection site reactions like redness or pain. Other side effects include joint pain, bronchitis, diarrhea, gastroenteritis, fungal skin infections, and herpes simplex infections.
Tremfya carries serious risks due to its effect on the immune system. It lowers the body’s ability to fight infections, increasing the risk of developing infections, including tuberculosis (TB), bacterial, viral, and fungal infections. Healthcare providers should screen patients for TB infection before starting treatment and monitor them closely for signs of infection during and after therapy.
Serious allergic reactions can occur, and patients should seek immediate medical attention if they experience symptoms such as rash, hives, swelling of the face, lips, mouth, or tongue, or breathing difficulties. Liver enzyme elevations can also occur. Individuals should discuss their medical history, including any past or current infections or other pre-existing health conditions, with their doctor before starting Tremfya treatment.
Expected Treatment Outcomes
Patients treated with Tremfya can anticipate improvements in their symptoms for both plaque psoriasis and psoriatic arthritis. For plaque psoriasis, the goal is to achieve clearer skin, with reductions in the scaling, redness, and thickness of psoriatic plaques. Many patients experience skin clearance over time.
In psoriatic arthritis, patients can expect a reduction in joint pain, swelling, and stiffness, which are hallmark symptoms of the condition. Studies have shown that many patients experience improvement in active psoriatic arthritis symptoms within 24 weeks of starting treatment, with sustained improvement possible over two years. The medication can also help reduce the progression of structural damage to joints.
Individual responses to Tremfya may vary, but many patients begin to see initial improvements within a few weeks, with sustained results observed over several months of consistent treatment. Some patients with psoriatic arthritis may also experience an improvement in fatigue.