Overall, medicines have different sizes and complexities – ranging from small molecules with simple molecular structures to highly complex proteins as well as advanced therapies.

The focus of this paper is follow-on versions of smaller protein products developed to be marketed following expiry of patent and data protection of the reference product. They are synthetically produced while the reference product is manufactured recombinantly.

In recent years, significant progress in manufacturing technologies using chemical synthesis has made it technically feasible and economically viable to produce smaller proteins via chemical synthesis. This has enabled generic companies to develop synthetic follow-on versions, also in cases where the reference product is biologically produced.