Biosimilars Compared to Generic Drugs
WHAT ARE BIOLOGICS AND BIOSIMILARS?
Definition
A wide range of medicinal substances are produced in living cell systems using biotechnology. There isn’t one universally recognised name for these products, but they have been described using terms such as biopharmaceuticals, biological products and as used in this website, biologics.
Biosimilars are successors to reference (i.e. original) biologic products, produced when patents relating to those reference products have expired (Figure 1). In order to develop a biosimilar, comparability with the reference product must be demonstrated. This takes several years of testing and clinical studies in order to meet the rigorous criteria required for licensing. This is to ensure that there are no significant differences in the quality, efficacy and safety of a biosimilar and its reference biologic.
Figure 1. Comparison of biologics and biosimilars
Adapted from Biosimilars Handbook, European Generic medicines Association, 2011
BIOSIMILARS COMPARED TO GENERIC DRUGS
Unlike generic drugs, biosimilars are not licensed purely on the results of pharmaceutical and bioequivalence studies. As well as demonstrating comparable efficacy and safety to their respective reference biologics, biosimilars must show that they are of the same equivalent quality as their reference products. Quality in this context refers to the controls and standards for all aspects of manufacturing, preparation and processing. The process of producing a biosimilar starts with the development of an equivalent host-cell clone followed by the second step of preparing cell bank clones which can take 1-1.5 years of research.1 Process development, fermentation, purification and manufacturing scale-up to reach the required standards can take another 1–1.5 years, whilst comparability testing, analytical characterisation, non-clinical and clinical studies can take a further 3.5-4.5 years1 (Figure 2). Thus, it takes many years to bring a biosimilar to market — far longer than producing a generic equivalent of a small molecule drug (Figure 3).
Figure 2. Timeline for development of a biosimilar medicine1
Adapted from Biosimilars Handbook, European Generic medicines Association, 2011
Figure 3. The pillars of biosimilar product development and marketing approval1
Adapted from Biosimilars Handbook, European Generic medicines Association, 2011
SMALL MOLECULE DRUGS COMPARISON
Biologics are 100 to 1000 times larger than small molecule drugs, such as aspirin, which is a relatively simple organic substance produced by chemical methods (Figure 4).
Figure 4. Comparison of the small-molecule drug aspirin and biologic products
Source: hospira