Starting a biologic or biosimilar medicine

This leaflet is intended to be given to any patient who starts a biologic or biosimilar medicine in the course of the treatment of any disease where these medications are prescribed for.

What is my medicine's name?

You may notice that your medicine has two names:

• the active medicine and
• the brand of the medicine on the packaging.

It is important that if the packaging changes, the active medicine name remains the same. The only time this will change is when your clinical team intentionally change your treatment. This will be discussed with you in detail.

You can search for patient information leaflets about medicines on the electronic medicines compendium website (opens in a new tab).

What is a 'biologic'?

Biologic medicines are complex medicines made or derived from a biological source. Because of the biological source and the manufacturing process, there is some variability in these medicines. The variability between batches of the same product is controlled and monitored during manufacturing to maintain this within defined and approved limits.

Biological medicines are used to treat many conditions including cancers, diabetes, arthritis, psoriasis and enzyme or hormone deficiencies.

What is a 'biosimilar'?

Biosimilar medicines are a highly similar copy of the original medicine (biologic).

The World Health Organization (WHO) defines a biosimilar as:

"a medicine that is similar in terms of quality, safety and effectiveness to the original licensed product."

NHS England defines a biosimilar as:

“a biological medicine which has been shown not to have any clinically meaningful differences from the originator medicine in terms of quality, safety and efficacy. Where NICE has already recommended the originator biological medicine, the same guidance will normally apply to a biosimilar of that originator.”​

What versions of my medicine are available in the UK?

Initially, when an original biologic medicine is produced, the pharmaceutical company who licensed the medicine will have a period of protection (several years) where they are the only company permitted to make and sell the medicine. As time goes on, other companies will be allowed to make a biosimilar of your medicine.

Are biosimilars safe?

The body in the UK that regulates medicines is the Medicines and Healthcare products Regulatory Agency (MHRA). All medicines have to pass rigorous tests for quality, biological activity, safety and effectiveness. Biosimilar medicines pass the same tests as the original biologic medicine.

What are the benefits?

You have personal goals to achieve with your treatment. You can expect to have the same results from your biosimilar as if you’d had the original biologic medicine to support you reaching these goals. Sometimes your treatment is provided in a new type of device such as an injection pen instead of an injection syringe.

There is a benefit to the NHS too. Biosimilars are usually provided at a much lower price than the original biologic medicine. This helps the NHS provide complex medicines at better prices and treat more patients than might otherwise be possible.

Will I be switched over to a biosimilar preparation?

The decision to switch over to biosimilar will be influenced by availability of the new preparation. Switching may take place at the point of a new prescription being written. You will be provided with training if the method of administration alters.

Will there be any side effects when I switch?

You shouldn’t experience any side effects when you switch from biologic to biosimilar as they contain the same active medicine.

Occasionally, some patients may experience some minor side effects when they take a new formulation of a medicine (eg pre-filled syringe to pre-filled pen or tablets to capsules). However, these should settle quickly, and we encourage all patients to persevere if these issues arise.

Please speak to your consultant, nurse or pharmacist if you think you are experiencing any new side effects that are more serious.

Contacts/further information

If you have questions regarding the content of this leaflet, please discuss them at your next appointment with your clinical service.

References/sources of evidence

• Electronic medicines compendium (opens in a new tab)
• NHS England Biosimilar Medicines:
  1. NHS England - Biosimilar medicines (opens in a new tab)
  2. NHS England - What is a biosimilar medicine? (opens in a new tab)

• World Health Organization (opens in a new tab)
• Medicines and Healthcare products Regulatory Agency (opens in a new tab)
• European Medicine Agency (opens in a new tab)