This information is for patients taking or considering taking biologic or biosimilar medicines. 

Biologic medicines

Most regular medicines are made with chemicals. 

Biologic medicines come from living cells that have been changed to produce a medicine. These medicines are more complex than regular medicines. This means they are more expensive to make.

Biologic medicines have been used for many years for a wide range of conditions. They include hormones such as insulin (used to treat diabetes) and growth hormones, as well as antibodies for the treatment of autoimmune diseases and cancers.

Biosimilar medicines

Generic medicines are copies of an original branded medicine. For example, supermarket own-brand ibuprofen is a generic version of Nurofen.

In the same way, a biosimilar medicine is a similar version of an original branded biologic medicine. However, it is not completely identical because of the larger and more complex structures involved.

The original biologic medicine is referred to as the ‘originator’.

An example is the medicine 'infliximab'. This is sold as the originator Remicade and the alternative biosimilar medicine Remsima.

Biosimilar medicines work in the same way as the originators. They are carefully tested to show there are no differences in safety and effectiveness.

Biosimilar medicines cost less than the originators. This means that the NHS can prescribe them to more patients.

Some medicines do not have a biosimilar version

New biologic medicines are developed all the time. For the first few years, cheaper biosimilar versions cannot be sold. This allows the developer to make back the cost of developing the new medicine. 

If your medicine is a newer biologic medicine, biosimilar versions may not yet be allowed. 

What it means for you

Whether you are starting treatment with a new biologic medicine or already using one, at some point you are likely to be switched to a biosimilar version. 

We expect you to have the same response and same side effects as you had with the originator medicine. All biologic drugs may stop being effective at some point, but this is no more likely to happen with the biosimilar than with the originator medicine.

If you receive your medicine as an infusion or injection on the Medical Day Unit, the medicine used will be changed to the biosimilar. You will be informed before this happens.

If you receive your medicine as a delivery to your home (homecare), you will be contacted by the homecare company to inform you of the change. Your deliveries will then change to the biosimilar.

If you have any concerns, contact the team looking after you. 

Contact information

For more information, contact whoever has prescribed your medicine(s), your local pharmacist or GP.