Biosimilars - What are they and how do they differ from the biologics

To understand what biosimilars are and how they differ to the current biologic drugs it is necessary to know a little bit about what biologic drugs are and how they are made. Unlike the more common standard disease modifying anti-rheumatic drugs (DMARDs), such as methotrexate and hydroxychloroquine which are small molecules and can be reproduced exactly, biologics are large molecules. They are manufactured in a different way to the standard DMARDs as are produced from a living organism that contains proteins from living cells. Because they are much larger and more complex than typical small molecule drugs, the manufacturing process for them is highly complicated and they are difficult to produce commercially.

Biosimilar is the term given to describe officially approved, subsequent versions of biologics made by a different company following the expiration of the patent on the original drug.  The new manufacturer does not have access to the original living cells that the original drug was made from, and the exact production process will be different, so they will not be exactly the same as the original biologic.  Biosimilars are permitted to have small, structural differences from the original but, these must not alter how well the drug works, how safe it is or how the drug reacts with the body’s immune system.

The following biosimilars have recently been licensed for use in the UK:- Inflectra, marketed by Hospira and Remsima, manufactured by Celltrion, which are essentially the infliximab (Remicade) biosimilar. They have been approved by the European Medicines Agency (EMA) for the treatment of inflammatory conditions including rheumatoid arthritis, ankylosing spondylitis and psoriatic arthritis. Although Inflectra and Remsima have been approved, a last minute extension of the original patent on Remicade means that they are now unlikely to be available in the UK before February 2015.

To read more about biosimilars and the work NRAS has been doing in regard to the advent of biosimilar medicines, please go to the NRAS website.

The EMA have also produced a very helpful information sheet which you can view on this link -