What is infliximab and how is it used?
Infliximab is a type of drug known as a biological therapy. It can be prescribed for:
In some cases, doctors may prescribe infliximab to treat certain types of vasculitis.
The immune system normally works to protect the body from infections. But in some conditions, the immune system produces too much of a protein called TNF (tumour necrosis factor). This causes inflammation, pain and damage to the body’s own tissues.
Anti-TNF drugs such as infliximab block the action of TNF to reduce this inflammation. They’re not painkillers, but can modify the disease and should start to improve your symptoms over a period of two to 12 weeks.
There are national and local guidelines about when infliximab can be used, which vary depending on which condition you have. You won’t be given infliximab if you haven’t tried other drugs appropriate for your condition first.
Before you’re prescribed infliximab, doctors will assess your condition and may use a scoring system to work out how active your arthritis is. Depending on which condition you have, this may be a formal scoring system, or it may be based simply on how many joints are tender and swollen.
Infliximab was originally produced under the name Remicade. Several other versions of infliximab – called Flixabi, Inflectra and Remsima – have since become available. These newer drugs are known as biosimilars and work in a similar way to the original drug.
Infliximab will usually be prescribed under one of the specific drug names above. However, other new versions of the drug may become available. If your specialist team suggests you change from one version of infliximab to another, you should discuss this with them before any change is made.
Is infliximab suitable for me?
You’ll have blood tests and other health checks before starting infliximab to make sure it’s suitable for you.
Your doctor will check for previous tuberculosis (TB) and hepatitis infection, as infliximab can increase the risk of these starting up again. If you test positive for either of these, you may need treatment before starting infliximab.
Your doctor may also suggest an HIV test. If you have HIV, this should be well controlled before starting infliximab.
Your doctor may decide not to prescribe infliximab if you’ve had or have:
- an active infection, or repeated or serious infections
- multiple sclerosis (MS)
- certain heart conditions
- scarring of the lung tissue (pulmonary fibrosis).
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 into a vein. This is called an intravenous infusion. It’s usually done in hospital, and takes about two hours. You’ll need to wait for another hour or two before you go home, in case you develop any side effects.
After the first infusion you’ll have another one two weeks later, and another four weeks after that. After the third infusion you’ll continue to have them every eight weeks. Once you’ve been on the treatment for a while, the infusions may take less time.
Because it’s a long-term treatment it’s important to keep having your infliximab infusions even if it doesn’t seem to be working at first. You’ll also need to keep taking it when your symptoms start to improve, to help keep the condition under control.
Side-effects and risks
Like all drugs, infliximab can sometimes cause side effects but most people won’t have any problems, and most of the more common side effects aren’t serious.
Common side effects include a blocked or runny nose, headaches, dizziness, flushing, a rash, stomach pain, indigestion or feeling sick. A faster or irregular heartbeat is also quite common – you should speak to your doctor if this happens to you.
Because infliximab affects the immune system it can make you more likely to pick up infections. Rarely, your body may not produce enough of the blood cells that help to fight infections or 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.
Some people may have a reaction to the infusion. This is more likely during or soon after the first few infusions. The healthcare professional giving the infusion will be looking out for any problems so that they can be quickly dealt with. The infusion will be stopped if the reaction is severe. If you think you may be having a reaction to the infliximab at any other time, contact your specialist team straight away for advice.
If you have a break in your infliximab treatment of more than 16 weeks, there may be a higher risk of an allergic reaction when you start the treatment again. Your doctor or nurse will monitor you more closely when you restart the treatment.
Anti-TNF drugs have been linked with some types of skin cancer – these can be readily treated when diagnosed early. Make sure you use suitable protective sun cream when you’re out in the sun, and see your doctor promptly if you notice any changes in your skin. 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. Symptoms include a rash, fever and increased joint pain. If you develop these symptoms you should contact your specialist team. This condition is generally mild and usually clears up if infliximab is stopped.
Regular check-ups and tests while you’re on infliximab will help to pick up any problems. This should happen at least every six months, though in some cases your doctor may suggest more frequent checks.
Tips to reduce your risk of infection
- Try to avoid close contact with people you know have an infection.
- Wash your hands regularly and carry around a small bottle of antibacterial hand gel.
- Keep your mouth clean by brushing your teeth regularly.
- Stop smoking if you’re a smoker.
- Make sure your food is stored and prepared properly.
- Try to keep your house clean and hygienic, especially the kitchen, bathrooms and toilets.
Effects on other treatments
You may 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 healthcare team.
You can carry on taking non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, or painkillers if needed, unless your doctor advises otherwise. 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 best to discuss vaccinations with your specialist team and, if possible, to have any vaccinations you may need before you start infliximab. Chickenpox vaccine may be recommended before starting infliximab if you haven’t had chickenpox.
Some vaccines may be less effective once you’ve started infliximab. However, pneumococcal vaccinations, which help to protect against pneumonia, and yearly flu vaccines are usually recommended.
Live vaccines – such as yellow fever, shingles, rubella and oral polio vaccines – aren’t recommended for people who are already on infliximab, because of the possible risk of developing these conditions.
Having an operation
Talk this over with your specialist doctors and surgeon. Depending on the type of surgery, they may advise you to stop infliximab for a time before and after the operation. Because infliximab affects your immune system, there may be an increased risk of infection following surgery.
There’s no known interaction between infliximab and alcohol. However, 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 specialist.
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 restart methotrexate until you stop breastfeeding.