What makes biological medicines different to other medicines?
To understand how biological medicines differ from other medicines, it helps to compare them to more common medicines that you may be familiar with, those made by chemical processes.
| Chemical medicines | Biological medicines | |
| Example | Aspirin | Infliximab |
| What do they look like under a microscope? | Small and simple, made up of 21 atoms | Very large and highly complex, made up of more than 20,000 atoms |
| How are they made? | Simple chemical process | Complex biological process using the latest technology to modify the genes to produce the active ingredients for the medicine |
| How do you take them? | Commonly taken as pills | Cannot be made into a pill and are given as an injection or infusion instead |
| Can we make copies? | Yes, the active ingredient will be 100% identical across all batches | No, we cannot make identical copies of biological medicines. It’s normal to find minor differences between batches of the same biological medicine |
| What are new brands of the same medicine called? | Generic medicine | Biosimilar medicines |
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