Renflexis®—Biosimilar for Remicade (infliximab)
Renflexis (infliximab-abda) is a biologic medication that is a “biosimilar” to Remicade (infliximab). It is approved to reduce signs and symptoms, help stop further joint damage, and improve physical function in patients with moderately to severely active rheumatoid arthritis (RA), in combination with methotrexate.
Renflexis can cause serious side effects such as lowering a person’s ability to fight infections. Some people, especially those 65 years and older, have experienced serious infections including tuberculosis (TB) and histoplasmosis. Some of these infections have been fatal. Those taking Renflexis should be monitored by their doctor for signs and symptoms of TB while being treated with Renflexis. Additionally, unusual cancers have been reported in children and teenage patients taking TNF-blocker medicines.
What are the ingredients in Renflexis?
The active ingredient in Renflexis is Infliximab-abda.
How does Renflexis work?
Renflexis is one of several monoclonal antibodies used to treat RA. Our bodies naturally produce antibodies, which are immune factors that act against bacteria, viruses, and other foreign organisms that invade and pose a threat to our health. Drug makers have engineered a variety of antibodies to target the mechanisms that cause certain diseases, including RA.
Like infliximab, Renflexis blocks the action of tumor necrosis factor-alpha (TNFα). TNF-α is an immune system signaling factor (called a cytokine) that plays an important role in swelling and inflammation. It is found in higher levels in the synovial fluid in the joints of patients with RA, and it is connected to inflammation as well as damage to bone and cartilage. Blocking TNF-α helps reduce the damage caused by the dysfunction of the immune system that is characteristic of RA.2 Further, in RA, treatment with infliximab products blocks inflammatory cells from getting into already-swollen areas of the joints.
What are the possible side effects of Renflexis?
The most common adverse reactions include:
- Respiratory infections, such as sinus infections and sore throat
- Stomach pain
Infusion reactions can occur up to 2 hours after an infusion of Renflexis. These symptoms include:
- Chest pain
- Low blood pressure or high blood pressure
- Shortness of breath
Renflexis affects a person’s immune system and can lower the ability of a person’s immune system to fight infections. Serious infections have happened in people receiving Renflexis. These infections include TB and infections caused by viruses, fungi, or bacteria that have spread throughout the body. Some patients have died from these infections.
The risk for lymphoma or other cancers may increase in children and adults taking TNF-α blocker medicines like Renflexis. There have been cases of unusual cancers in children and teenage patients using TNF-blocking agents, such as Renflexis. Other rare but serious side effects include Hepatitis B reactivation. Liver toxicity, heart failure, cytopenias (reduction in mature blood cells), hypersensitivity (serious infusion reactions including anaphylaxis or serum sickness-like reactions), demyelinating disease, and lupus-like syndrome. Note that this is not an exhaustive list of side-effects. For more information on adverse effects, see the FDA black box warning for Renflexis.
Things to note about Renflexis
Before taking Renflexis, it’s important to tell your doctor if you:
- think you have an infection. You should not start taking Renflexis if you have any kind of infection.
- are being treated for an infection.
- have signs of an infection, such as a fever, cough, flu-like symptoms.
- have any open cuts or sores on your body.
- get a lot of infections or have infections that keep coming back.
- have diabetes or an immune system problem. People with these conditions have a higher chance for infections.
- have TB, or have been in close contact with someone with TB.
- live or have lived in certain parts of the country (such as the Ohio and Mississippi River valleys) where there is an increased risk for getting certain kinds of fungal infections (histoplasmosis, coccidioidomycosis, or blastomycosis). These infections may develop or become more severe if you take Renflexis. If you do not know if you have lived in an area where histoplasmosis, coccidioidomycosis, or blastomycosis is common, ask your doctor.
- have or have had hepatitis B.
- use the medicines Kineret (anakinra), Orencia (abatacept), Actemra (tocilizumab), or other medicines called biologics used to treat the same conditions as Renflexis.
After starting treatment with Renflexis, if you have any sign of an infection including a fever, cough, flu-like symptoms, or have open cuts or sores on your body, call your doctor immediately. Renflexis can make you more likely to get infections or make any infection that you have worse.
Tell your doctor about all the medicines you take, including prescription and non-prescription medicines, vitamins and herbal supplements.