Article date: February 2008
What is a biosimilar?
A similar biological medicinal product (biosimilar) is a new biological product that has been developed to be similar to an existing biological product (“reference” product).
Biological products are fundamentally different from standard chemical products in terms of their complexity, and it is unlikely that the biosimilar product will have an identical structure to that of the “reference” product, thereby requiring evidence of safety and efficacy before approval. In this regard, biosimilars are different to the more familiar generic products. Examples of biosimilar products include:
|Reference product (substance)||Biosimilar products|
|Genotropin (somatropin),||Valtropin, Omnitrope|
|Eprex (epoetin alpha)||Binocrit (epoetin alpha)|
|Eprex (epoetin alpha)||Retacrit (epoetin zeta)|
Prescribing of biosimilars
All biosimilar products are prescription only medicines (POM). When prescribing biological products, it is good practice to use the brand name. This will ensure that automatic substitution of a biosimilar product does not occur when the medicine is dispensed by the pharmacist. Products (biosimilar and reference) that have the same international non-proprietary name (INN) are not to be presumed identical for the reasons given above.
Reporting suspected ADRs for biosimilars
In view of the subtle differences that are likely to exist between biosimilar products, even though the clinical effect of the products may be similar, and in view of the complexity of these molecules, it is very important that adverse drug reactions (ADRs) are properly assigned to the suspect product. Particular care needs to be taken when reporting ADRs associated with biosimilar products.
To ensure that any ADR that you report is assigned to the correct product, it is important that the product name rather than the substance name is used for reporting. For example, if reporting an ADR to Eprex, please report using the name Eprex rather than epoetin alpha.
Further information about biosimilar products can be found on the website of the European Medicines Agency:
Article citation: Drug Safety Update Feb 2008; Vol 1, Issue 7: 8