The use of zinc-initiated crystallization had dramatically improved insulin purity by the 1960s. Research into the causes
of antibody generation in response to insulin and allergenic reactions led both Eli Lilly & Co. and Novo Nordisk (Novo and
Nordisk were two separate companies at the time) to investigate new methods of purification: proinsulin, glucagon, somatostatin,
and modified forms of insulin such as desamido insulin were identified as the root cause of immunogenicity of bovine- and
porcine-derived products.30 Enabled by the introduction of columns for large-scale chromatography using "soft" gels and scale-up of insulin purification
on Sephadex G-50, Eli Lilly introduced "single peak insulin."31
This was termed so because it gave a single peak in analytical gel filtration. Novo introduced a "monocomponent" or "MC" insulin
in 197332 purified by ion exchange chromatography, which gave a single band in electrophoresis.
Throughout this period, Pharmacia Fine Chemicals dominated the chromatographic separations industry, launching Sepharose in
1966, Protein A Sepharose in 1975, HIC products in 1977, and IMAC in 1979. IBF (Industrie Biologique Française), a Rhône-Poulenc
company (now BioSepra, part of Pall Corp.), was also active, as were Whatman and Bio-Rad Laboratories. Tosoh (Toyo Soda),
in alliance with Rohm & Haas, focused on methacrylate supports and became known for its products for HIC and size exclusion.
Biologics research had a significant base in academia rather than the pharmaceutical industry.33 Some products were in the domain of government defense laboratories, partly for reasons of national security and because
specialized microbiological competence was located in such institutions. At this time, the focus of the pharmaceutical industry
was on the development of new chemical entities (NCEs), but that changed significantly with the molecular biology revolution
of the 1980s.
THE AGE OF DOWNSTREAM PROCESSING
The Asilomar conference of 1975 has been called the "Woodstock of molecular biology"34 and has served as a questioning reminder of the power of recombinant DNA technology. The conference triggered the first
guidelines for research on rDNA35 and marked the beginning of biopharmaceutical regulation in the United States and elsewhere. From 1980 to 1994, 29 new biologic
entities (NBEs), including 10 new recombinant entities, were approved, with an average time of 61 months from investigational
new drug (IND) to licensure, 38.9 months shorter than for NCEs during the same 15 year period.36 This was the era of molecular biology. Transiently, chromatography became a tool to expedite analysis and product purification
of what could be termed "new age" biologics. However, a new discipline of downstream processing was minted, and now biopharmaceutical
manufacturing divided into upstream (bacterial and yeast fermentation or mammalian cell culture) and downstream.
In contrast to the early years, new biopharmaceutical approvals currently run at about 40 per year in the US. The Biotechnology
Industry Organization cites 254 drugs approved for 385 indications from 1982 to 2005.37 In 2006, CDER approved only four new biological products and CBER approved nine new biological products. The number of products
entering clinical trials also has tapered off since 1980. Clinical and approval phase lengths vary widely, with a trend to
longer clinical phases. In 2003, the Tufts Center for the Study of Drug Development conservatively projected that more than
30 new biotherapeutics would be successful in the next six to seven years.38
In the European Union, 88 recombinant products and MAbs have been approved by 2002, representing 36% of all new approvals
since 1995 under the centralized European drug approval system.39 The success rate for biologics is significantly higher than for small-molecule NCEs,36 partly because of the way they are developed. A key area of focus for the safety of small molecules is their side effects,
whereas the concern for biologics is immunogenicity.40