1. Manufacturing differences between biopharmaceuticals and low molecular weight drugs Basant Sharma, PhD Vice President, Pharmaceutical Technology Centocor Raritan, New Jersey, USA 1 September 2005

2. Manufacturing low molecular weight drugs Low molecular weight drugs are made by adding and mixing together known chemicals and reagents, in a series of controlled and predictable chemical reactions This is organic chemistry 2

3. Manufacturing biopharmaceuticals Biopharmaceuticals are made by harvesting the proteins that are produced and secreted by specially genetically engineered living cells This is genetic engineering 3

4. Differences in manufacturing • The manufacturing process for a biopharmaceutical is far more complex than that for a low molecular weight drug • For biopharmaceuticals, much more than for low molecular weight drugs, the quality of the end product (including therapeutic efficacy and safety) is dependent on the manufacturing process These differences clearly apply to biosimilars as well as to original biopharmaceuticals 4

5. How are biopharmaceuticals made? • Develop host cell • Establish a cell bank • Protein production • Purification • Analysis • Formulation • Storage and handling Each of these stages can have a major influence on the characteristics of the end product 5

6. 1. Develop host cell • Identify the human DNA sequence for the desired protein • Isolate the DNA sequence • Select a vector to carry the gene • Insert the gene into the genome of a host(a suitable bacterial or eukaryotic cell) The exact DNA sequence and the type of host cell used will significantly influence the characteristics of the product 6

7. 2. Establish a cell bank A cell bank is then established, using an iterative and elaborate cell screening and selection process, yielding a unique master cell bank No two master cell banks are exactly alike 7

8. 3. Protein production The ‘engineered’ cells are then cultured on a large scale under strictly defined growth conditions that optimize cellular production and secretion of the desired protein Cell bank frozen vial recovery 8

9. 3. Protein production (cont.) Spinners Bioreactor The conditions under which cells are cultured can affect the nature of the end product 9

10. 4. Purification • The cell culture medium is harvested • Undesired proteins and impurities are removed, in order to optimize the purity of the desired protein 10

11. 4. Purification (cont.) • Achieving maximum purity means that a considerable amount of product is lost Large cost implications Any change in the purification process can affect the clinical characteristics of the product 11

12. 5. Analysis • Protein molecules are analysed for uniformity in terms of structure and potency • A wide variety of analytical tools is used to examine: • 3D structure • Aggregation • Isoform profile, including glycosylation patterns • Heterogeneity • Potency These tests remain limited in their ability to detect all product characteristics that may affect clinical efficacy and safety 12

13. 6. Formulation • After isolation, purification, and testing, the therapeutic protein is formulated: • e.g. adding antioxidants, osmotic agents, buffers • Formulation is a key step in stabilizing the protein The components of the formulation, and the process used, can significantly affect the product’s behaviour in patients 13

14. Rotary piston pumps Stoppers Filling needles Product Syringes 6. Formulation (cont.) Syringe filling 14

15. 7. Storage and handling • The formulated product is stored, handled, and administered to patients • Biopharmaceuticals are very sensitive to temperature changes and/or shaking • Strict storage and handling conditions are therefore essential for maintaining product integrity and stability Poor adherence to (cold) storage requirements can affect clinical efficacy and safety 15 Crommelin DJA. EJHP 2003;1:73-94.

16. Additional issues • Each of the seven main steps consists of many smaller steps that must also be carefully controlled and validated • Experienced personnel familiar with the subtle nuances and proclivities of the process are essential for a consistent and productive operation • The average time from first cell culture to finished biological product is 8–9 months Manufacturing biopharmaceuticals is a complex, high-tech, and time-consuming process 16

17. Conclusions • The manufacturing process for biopharmaceuticals (and biosimilars) is far more complex than for low molecular weight drugs (and generics) • Any (minor) change made at any stage may have a critical effect on the clinical efficacy and safety • Major manufacturing changes include: • producing a biosimilar • opening/starting a new production site • scaling-up to meet market demands ‘The process is the product’ 17

18. Points to consider • Can a new manufacturer produce a biosimilar that is similar enough to the original biopharmaceutical to be considered the same? • How can the level of similarity be established without access to the bulk material? • Are there risks associated with currently undetectable differences? How similar is similar enough? 18