Abatacept (brand name: Orenica) is the first in a new class of biologic agents used in the treatment of RA. The members of this class are collectively called co-stimulation modulators.
T cells play an important role in your immune system by fighting off viruses, bacteria, and other disease-causing agents. A normal immune system leaves healthy body tissues alone. Unfortunately in RA, for reasons that are not clear, T cells become activated and attack healthy tissues. Activated T cells play a central role in the inflammatory cascade, leading to the joint inflammation and destruction characteristic of RA. Abatacept has the ability to block the activation of the T cells, thereby decreasing the signs and symptoms of RA.
Abatacept is approved by the FDA for treatment of people with moderately to severely active RA who have shown an inadequate response to one of the DMARDs (e.g., methotrexate, leflunomide, or hydroxychloroquine) or TNF inhibitors (etanercept, adalimumab, or infliximab). It is commonly prescribed along with methotrexate or other DMARDs, but should not be administered with a TNF inhibitor owing to the increased risk of side effects with this combination.
Similar to infliximab, abatacept is given as an intravenous infusion. Whereas infliximab takes two hours to infuse, however, abatacept can be administered over 30 minutes. Abatacept needs to be administered every month.
Potential side effects of abatacept include allergic reactions, an increased risk for infections, and cancer. In particular, treatment with abatacept can make you more prone to getting infections or make any infection you already have worse. It is important to tell your doctor if you think you have any infections before beginning therapy with abatacept. If you develop a fever, cough, chills, or pain or burning when you urinate during your treatment with abatacept, you should see your doctor immediately or go to the emergency room to be evaluated.