On Oct. 28, 1982, after only 5 months of review, the U.S. Food and Drug Administration (FDA) approved Humulin, Eli Lily’s recombinant insulin made from Genentech’s specially modified bacteria. It was the first drug made from recombinant DNA technology, and among the first genetically engineered products to be available to consumers.

In 1978, scientists at City of Hope and Genentech had jointly developed a method for producing biosynthetic human insulin (BHI) using recombinant DNA technology in a unique multi-step process. After extracting and manipulating the two polypeptide chains, A and B, that make up the human insulin gene, they inserted these into a common bacteria, which they programmed genetically to produce large amounts of insulin.

Eli Lilly subsequently signed an agreement with Genentech to use the rDNA method to make human insulin commercially available. The development of BHIs not only promised to resolve the supply and price volatility inherent in the production of animal insulins, but also enabled the development of efficient manufacturing design and protocols to achieve even greater purity and standard adherence. Yet, perhaps more importantly, the introduction of synthetic insulin marked a paradigm shift in diabetes therapeutics that soon led to the development of other non-animal derived products.