IL6 receptor inhibitors tocilizumab and sarilumab

Tocilizumab was approved for use in patients with RA in 2009, while sarilumab was approved in 2017. Both drugs target the IL6 cells that make up part of the immune system’s response in the body.

Original Biologic drugBiosimilars (up-to-date at time of printing)Method of administration
Tocilizumab (RoActemra)N/Aintravenous infusion, once every 4 weeks or weekly subcutaneous (under the skin) injection
Sarilumab (Kevzara)N/Asubcutaneous (under the skin) injection every other week

How does it work?

As with other biologic drugs, tocilizumab and sarilumab work by targeting proteins called cytokines, which are responsible for the inflammation caused by the immune system’s response. In this case, the cytokines being targeted are called ‘IL6 receptors’.

Most commonly reported side effects

As with any medication, tocilizumab has a number of possible side effects, although it is important to remember that these are only potential side effects. They may not occur at all.

Common side effects may include:

 Tocilizumab and sarilumab:

  • upper respiratory tract infections with typical symptoms such as cough, blocked nose, runny nose, sore throat and headache
  • high blood fat (cholesterol) levels
  • neutropenia (low neutrophils, which are a type of white blood cell)
  • increased liver enzymes (an indication that the liver is affected)
  • injection site reactions
  • upper respiratory infections and urinary tract infections

More information on side effects can be found in the patient information leaflet for tocilizumab. Remember to report any concerns about possible side effects to the doctors.

IL6 inhibitors with other medicines

Some biologic drugs are known to interact poorly with other biologics. You may therefore be asked to leave a gap between stopping one biologic drug and starting another so that the first drug has time to start coming out of your system.

Tocilizumab is known to interact poorly with the anti-psychotic drug ‘clozapine’.

IL6 inhibitors during pregnancy and breastfeeding

Tocilizumab and sarilumab should not be used during pregnancy unless clearly necessary, due to limited data on its safety during pregnancy. There is also limited evidence on its safety during breastfeeding. The decision of whether or not to stay on the drug while breastfeeding, and whether or not to continue breastfeeding should therefore be discussed with your rheumatologist and will weigh up the benefits of breastmilk to your baby with the benefits to your health of being on this drug.

IL6 inhibitors and alcohol

You can drink alcohol on these medications. However, it is not uncommon when taking a biologic drug to be on other medications, where different guidance applies. Methotrexate, for example, can affect the liver, so for those taking methotrexate alongside their biologic, moderate intake of alcohol is recommended in line with government guidelines.

IL6 inhibitors and immunisations/ vaccinations

Live vaccines (measles, mumps, rubella, i.e. MMR, chickenpox, oral polio (NOT injectable polio), BCG, oral typhoid and yellow fever) cannot be given to anyone already taking tocilizumab or sarilumab. If the treatment has not yet been started, it is important to seek advice on how long a gap to leave after having a live vaccine.

Medicines in rheumatoid arthritis

We believe it is essential that people living with RA understand why certain medicines are used, when they are used and how they work to manage the condition.