Tocilizumab

 

What is Tocilizumab?

Tocilizumab is a targeted disease modifying anti-rheumatic drug (DMARD) that is used to reduce inflammation produced by the body. In certain diseases the immune system is over active, this can target healthy tissues such as joints and blood vessels. Tocilizumab works on the inflammatory pathway to block a protein called IL-6, thereby reducing the symptoms you get from arthritis such as pain and joint swelling, vasculitis such as headaches and reduces the chance of further damage to the joints or organs.

 

What is Tocilizumab used for?

Tocilizumab is used for the treatments of inflammatory diseases such as rheumatoid arthritis and giant cell arteritis (GCA).

 

How is it taken?

Tocilizumab can be taken in 2 ways and can be given alongside other DMARDs such as methotrexate, or taken on its own.

 

Subcutaneous injection

Tocilizumab can be taken as an injection into the layer of fat between the skin and muscle. This is called a subcutaneous injection and is usually given into the thigh or abdomen. It is given at a dose of 162mg once a week.

The injection device is available as a pen or prefilled syringe. It should be stored in the fridge at home.

You will require your bloods to be monitored whilst on the subcutaneous injections; these are done every 8 weeks for the first 4 months and then every 3 months thereafter. If you are on other DMARDs that require blood monitoring, this should be continued as well.

 

Infusion

It can also be given as an injection into the vein through a drip. This is called an intravenous infusion and is usually given in the rheumatology day unit. You will be monitored throughout and for 1-2 hours after this to make sure you have not developed and side effects. The dose is calculated from your weight and it is given every 4 weeks.

Whilst you are receiving the infusions you will need your bloods monitored, this is initially done every month for 6 months, after this it can be stepped down to every 3 months.

 

The medication can take up to 12 weeks to have an effect. You will be reviewed in clinic at around 3-4 months to see how you are getting along.

If you symptoms are well controlled, your doses can be gradually reduced. Increasing the time between injections does this.

 

Side effects 

There are a few possible side effects that can occur in a small number of people that take tocilizumab, these include:

 

• Sore throat, stuffy nose and headaches
  • These usually settle after taking the medication for a few weeks.
• Increased risk of infections
  • As tocilizumab dampens the immune system, you can be more prone to infection. You should be seen by your GP if you feel unwell in case you need antibiotics. You must temporarily stop your injections/ infusions whilst you are unwell and receiving treatment, they can be started up again when you feel well.
  • You should try to avoid contact with others that have chicken pox or shingles.
• Subcutaneous injection site reactions
  • Irritation, rashes and blistering can occur.
  • Mild steroid creams and antihistamines can be used to settle things down. If these don’t work, then you should see your GP.
• Infusion reactions
  • Sometimes people can have a reaction whilst receiving the drip. Your observations including blood pressure and pulse are regularly checked.
  • If you have a severe reaction, no further tocilizumab will be given.
• High cholesterol
  • Tocilizumab can sometimes increase the level of cholesterol (fat) in the blood. This is checked at your 3 monthly blood tests.
• Liver derangement
  • Occasionally tocilizumab can increase the levels of liver enzymes seen on blood tests, this is often temporary. Trials have not shown any damage to the liver when this occurs.
• Bowel symptoms
  • Change in bowel habit and abdominal pain can sometimes occur. This can sometimes be due to underlying bowel condition called diverticulitis, treatment with tocilizumab will have to stop and your should contact your doctor about these symptoms.

 

Cautions of use 

Interactions with other medications

• Your doctor will check if there are any medications that could interact.
• You can carry on taking your usual painkillers including NSAIDs.

Contraindications of other conditions

• Before starting any biological therapy, your bloods will be checked for infections that can become active again when the immune system is suppressed, this includes hepatitis B, C and HIV. A blood and chest X-ray is taken to exclude previous TB exposure. If you are found to have had previous TB exposure you may need to start preventative antibiotics for a short period before the tocilizumab is commenced.
• If you have a history of diverticulitis, tocilizumab cannot be used.
• Tocilizumab is not safe to be used if you are being investigated for or have been diagnosed with cancer.

Operations

• Tocilizumab should be withheld for 1 week after the last dose would have been due. Depending on how you take your tocilizumab, surgery can be scheduled as below:
  • Subcutaneous injections- schedule from week 3
  • Infusions- schedule from week 5

During pregnancy and breastfeeding

• There is currently no data on tocilizumab in pregnancy or breastfeeding. Therefore it should not be used.
• If you are considering starting a family, tocilizumab should be stopped at least 12 weeks before trying to conceive.
• There is no data on the use in males who are trying to conceive.

Alcohol

• Alcohol and tocilizumab do not interact, however it is recommended to take alcohol within moderation, following the guidelines of less than 14 units weekly.

Vaccinations

• Flu and the pneumonia vaccine are safe and recommended whilst taking tocilizumab.
• Live vaccines including the shingles vaccine should not be given due to the dampening down of the immune system.

 

Useful Links

Versus Arthritis: http://www.versusarthritis.org