What is infliximab?
In rheumatoid arthritis and some other inflammatory conditions, too much of a protein called TNF is produced in the body, causing inflammation, pain and damage to the bones and joints. Anti-TNF drugs such as infliximab block the action of TNF and so reduce this inflammation. They're not painkillers, but can modify the disease and should start to improve your symptoms over a period of 2–12 weeks.
Infliximab can be prescribed by a consultant rheumatologist for:
There are national and local guidelines that determine when infliximab can be used and these vary depending on the condition.
Are there any reasons why infliximab won't be prescribed?
Infliximab won't be prescribed if:
- your arthritis isn't active
- you have an infection
- you haven't tried other drugs appropriate for your condition.
Doctors sometimes use a score known as DAS28 to work out how active your arthritis is. This counts how many of 28 specific joints are tender and swollen, and looks at inflammation levels in a blood test. You'll also be asked to score how well you feel on a scale of 0 to 10.
Your doctor may decide not to prescribe infliximab if you've had or have:
- repeated or serious infections
- multiple sclerosis (MS)
- a serious heart condition
- lung fibrosis (scarring of the lung tissue).
You'll have a chest x-ray and a test to check whether you’ve ever been exposed to tuberculosis (TB). You may need treatment for latent (asymptomatic) TB before starting infliximab.
You may also be checked for previous hepatitis infection, as infliximab may increase the risk of hepatitis being reactivated.
You'll probably have further checks while you're on infliximab to monitor its effects.
If infliximab isn't suitable for you your doctor will discuss other treatment options with you.
How is it taken?
Infliximab is given through a drip (intravenous infusion) into your arm.
It's usually done in hospital, and takes about two hours. You'll need to wait for another 1–2 hours before you go home in case you develop any side-effects.
After the first infusion you'll have another one two weeks later and then one four weeks after that.
After the third infusion you'll continue to have one every eight weeks. The infusions may take less time, and you may be able to have them at home, once you're established on the treatment.
How long does it take to work?
Your symptoms should start to improve over a period of 2-12 weeks.
Because it's a long-term treatment it's important to keep taking infliximab (unless you have severe side-effects):
- even if it doesn't seem to be working at first
- even when your symptoms start to improve – to help keep the disease under control.
Infliximab was originally available only under the brand name Remicade.
More recently, two drugs called Inflectra and Remsima have become available. These newer drugs are referred to as 'bio-similars' because they're made to act in the same way as the original drug.
Because these drugs are newer, we don't yet know as much about them in terms of safety and effectiveness in all the situations described in these pages.
Side-effects and risks
The most common side-effects include a blocked or runny nose, headaches, dizziness, flushing, a rash, stomach pain or indigestion.
Because infliximab affects the immune system it can make you more likely to pick up infections. Rarely, your body may fail to produce enough of the blood cells that help to fight infections or to stop bleeding.
Tell your doctor or rheumatology nurse straight away if you develop any signs of infection such as a sore throat or fever, or have unexplained bruising, bleeding or paleness, or any other new symptoms that concern you. If any of these symptoms are severe, your infliximab may need to be stopped.
You should also see your doctor if you develop chickenpox or shingles or come into contact with someone who has chickenpox or shingles. These infections can be severe if you’re on infliximab. You may need antiviral treatment, and your infliximab may be stopped until you're better.
Anti-TNF drugs have been associated with some types of skin cancer – these can be readily treated when diagnosed early. Research so far hasn't shown an increased risk of other cancers.
Very rarely, people taking infliximab may develop a condition called drug-induced lupus, which can be diagnosed by a blood test. Symptoms include a rash, fever and increased joint pain. If you develop these symptoms you should contact your rheumatology team. This condition is generally mild and usually clears up if infliximab is stopped.
If you have an interruption in your infliximab treatment of more than 16 weeks, there's an increased risk of an allergic reaction when you start the treatment again. Your doctor or infusion nurse will monitor you more closely when you restart the treatment.
Reducing the risk of infection
- Try to avoid close contact with people with severe active infections.
- For advice on avoiding infection from food, visit NHS Choices - 10 ways to prevent food poisoning.
Effects on other treatments
You'll probably be taking methotrexate as well as infliximab. Check with your doctor before starting any new medications, and always remember to mention you're on infliximab if you're treated by anyone other than your usual rheumatology team.
Don't take over-the-counter preparations or herbal remedies without discussing this first with your healthcare team.
It's recommended that you carry a biological therapy alert card, which you can get from your doctor or rheumatology nurse, so that anyone treating you will know you’re on infliximab.
It's usually recommended that people on infliximab avoid live vaccines such as yellow fever. However, sometimes a live vaccine may be necessary – for example rubella vaccination in women of childbearing age.
If you're offered shingles vaccination (Zostavax) it's best if you can have it before starting on infliximab. Shingles vaccination isn't recommended for people who are already on infliximab.
Pneumococcal vaccinations (which give protection against the commonest cause of pneumonia) and yearly flu vaccines don't interact with infliximab and are recommended.
Having an operation
Talk this over with your specialists. It's likely you will be advised to stop infliximab for a time before and after surgery.
There's no known interaction between infliximab and alcohol. If you're also taking methotrexate, you should only drink alcohol in small amounts – generally no more than 14 units per week for adults.
In some circumstances your doctor may advise lower limits, because methotrexate and alcohol can interact and damage your liver.
Fertility, pregnancy and breastfeeding
If you're planning to try for a baby, if you become pregnant, or if you're thinking of breastfeeding we suggest you discuss your medications with your rheumatologist.
Current guidelines state that infliximab can be used during pregnancy and in men trying to father a child. If it's used during pregnancy it will usually be stopped after four months. If it's used after this, it's possible, but not proven, that it may increase the risk of infection in the newborn baby.
However, if there's concern that your arthritis may flare up if infliximab is stopped then you can continue with it throughout pregnancy – in this case, your baby should not have any live vaccines (such as BCG) until they're seven-months old.
Women who are also on methotrexate should stop taking it and use contraception for at least three months before trying for a baby.
The guidelines state that there's no need for men to stop methotrexate when trying to father a baby. There's only limited information about the use of infliximab while breastfeeding. Small amounts of infliximab may pass into the breast milk, but this doesn't appear to be harmful.
You should not re-start methotrexate until you stop breastfeeding.