Quality Control of Protein and Peptide Drugs: Monoclonal Antibodies and some Biological Response Modifiers Derived by Recombinant DNA Technology

Monoclonal antibodies have found a wide and varied use in many areas of biomedical research, such as diagnosis, tumour imaging and immunopurification, and some of these protein products are already in use or will soon be used as therapeutic agents. Products derived by recombinant DNA technology, for instance biological response modifiers, offer prospects to develop new medicines. As for all other drugs, the quality of biotechnological products, intended for use in man or animal, should be established. Because of the complex nature of these proteins, when compared with a conventionally produced chemical product, and the production process, which may introduce several contaminants which are hard to detect, in-process control is a prerequisite. In order to understand die in-process controls, the theory of monoclonal antibodies as well as the theory of recombinant DNA technology is reviewed. Subsequently, the quality control and the validation of these tests are discussed. The main risk factors, being the contamination with DNA and viruses, and the purity and identity of the final product are underlined. As supplement, the main biological and biochemical characteristics of the interleukins, tumour necrosis factor, interferons, and colony stimulating factors are reviewed.