Inflectra is a biologic medication used to treat several chronic inflammatory conditions, including Crohn’s disease, ulcerative colitis, rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, and plaque psoriasis. It’s a biosimilar to Remicade (infliximab), meaning it works the same way and is approved for the same conditions, but is made by a different manufacturer and typically costs less.
How Inflectra Works
Inflectra belongs to a class of drugs called TNF blockers. TNF-alpha is a protein your immune system produces that triggers inflammation. In autoimmune conditions, your body makes too much of it, which drives the pain, swelling, and tissue damage you experience. Inflectra binds to TNF-alpha with high affinity, both in the bloodstream and on cell surfaces, and prevents it from attaching to its normal receptors. This effectively dials down the overactive inflammatory response at its source.
Conditions Inflectra Treats
The FDA has approved Inflectra for six conditions in adults and two in children ages 6 and older.
Crohn’s Disease
Inflectra is approved for moderate to severe Crohn’s disease in both adults and children 6 and older. It’s typically used when standard treatments like corticosteroids or immunosuppressants haven’t provided enough relief. The goal is to reduce symptoms, achieve remission, and help heal the intestinal lining.
Ulcerative Colitis
Like Crohn’s, ulcerative colitis involves chronic inflammation in the digestive tract, but it specifically affects the colon. Inflectra is approved for moderate to severe cases in adults and children 6 and older who haven’t responded well to conventional therapies.
Rheumatoid Arthritis
For rheumatoid arthritis, Inflectra is used alongside methotrexate to reduce joint inflammation, slow joint damage, and improve physical function. It’s reserved for moderate to severe cases where methotrexate alone isn’t doing enough.
Ankylosing Spondylitis
This condition causes chronic inflammation in the spine and large joints, leading to stiffness and pain. Inflectra can reduce inflammation and improve mobility in people with active disease.
Psoriatic Arthritis
Psoriatic arthritis combines joint inflammation with the skin plaques of psoriasis. Inflectra targets the underlying inflammation driving both the joint and skin symptoms.
Plaque Psoriasis
For adults with chronic, severe plaque psoriasis who are candidates for systemic therapy, Inflectra can significantly reduce the thick, scaly skin patches that characterize the condition.
What It Means to Be a Biosimilar
Inflectra was the first biosimilar to Remicade approved by the FDA. Remicade (infliximab) has been on the market since 1998. A biosimilar isn’t a generic in the traditional sense. Because biologic drugs are made from living cells, they’re far more complex than small-molecule pills, so an exact copy isn’t possible. Instead, the FDA requires extensive testing to confirm a biosimilar is “highly similar” to the original, with no clinically meaningful differences in safety, potency, or effectiveness.
One distinction worth knowing: Inflectra was approved as a biosimilar but not as an “interchangeable” product, which is a separate FDA designation that would allow pharmacists to substitute it for Remicade without a prescriber’s involvement. In practice, your doctor can still prescribe Inflectra directly, and many insurance plans prefer it because of lower cost.
How Infusions Work
Inflectra is given as an intravenous infusion, not a pill or self-injection. You’ll receive it at an infusion center, hospital, or sometimes a doctor’s office. The infusion typically takes about two hours, though you may be monitored for some time afterward.
Treatment starts with three “loading” infusions spaced closely together: the first at week 0, the second at week 2, and the third at week 6. After that, you move to a maintenance schedule, typically every 8 weeks for most conditions. Ankylosing spondylitis is the exception, with maintenance infusions every 6 weeks. The dose is calculated based on your body weight. Most conditions use 5 mg per kilogram, while rheumatoid arthritis uses a lower dose of 3 mg per kilogram.
Common Side Effects
The most frequently reported side effects (occurring in more than 10% of patients) are upper respiratory infections, infusion-related reactions, headache, and abdominal pain. In clinical trials, about 20% of patients experienced some type of infusion reaction, compared to 10% on placebo. These reactions can range from mild flushing or headache during the infusion to more serious allergic responses, though severe reactions are uncommon.
Other side effects reported in at least 5% of patients include nausea (21%), sinusitis (14%), sore throat (12%), coughing (12%), bronchitis (10%), rash (10%), indigestion (10%), fatigue (9%), joint pain (8%), urinary tract infections (8%), fever (7%), itching (7%), and high blood pressure (7%). Many of these overlap with symptoms people already experience from their underlying condition, so it can be hard to tell what’s caused by the drug versus the disease itself.
Serious Risks to Know About
Inflectra carries a boxed warning, the FDA’s most serious safety alert, for two categories of risk: serious infections and certain cancers.
Because Inflectra suppresses part of your immune system, it increases your risk of serious infections, including tuberculosis, bacterial sepsis, and invasive fungal infections. Before starting treatment, you’ll be tested for latent tuberculosis and hepatitis B. If either test is positive, those infections need to be treated before Inflectra can begin. People who live in or travel to areas where certain fungal infections are common should be aware of that additional risk. Treatment should not be started during any active infection.
Cases of lymphoma and other cancers have been reported in patients taking TNF blockers, including in children and adolescents. A rare but fatal type of lymphoma called hepatosplenic T-cell lymphoma has occurred, almost always in patients who were also taking other immune-suppressing medications at the same time.
Inflectra is not appropriate for people with moderate or severe heart failure at doses above 5 mg/kg, and it can sometimes worsen heart failure symptoms even at standard doses. It’s also contraindicated if you’ve had a severe allergic reaction to infliximab products or to any mouse-derived proteins, since the drug contains components originally derived from mouse cells. Liver problems, including jaundice and significant elevations in liver enzymes, have also been reported and require stopping the medication. Cardiovascular events, including heart attacks, strokes, and abnormal heart rhythms, have occurred during or within 24 hours of an infusion, though these are rare.