Technology & Medicine › Digital age › Genetic engineering (recombinant DNA)
Biotech drugs (human insulin)
1978 (Genentech); approved 1982· Invention or discovery· Germs, drugs & genetics
Well documentedSolid records, physical evidence or scientific consensus.
Medicines made by genetically engineered living cells, starting with human insulin produced by bacteria.
See it on the Technology & Medicine map →How it works
Genentech, founded in 1976 in South San Francisco, and the City of Hope medical center made synthetic genes for the two chains of human insulin, placed them in E. coli bacteria, and in September 1978 announced the bacteria were producing it. Eli Lilly scaled up production, and in 1982 the US approved Humulin, the first drug made with recombinant DNA. Growth hormone, the anemia drug EPO, and antibody drugs for cancer and arthritis followed.
Why it mattered
It replaced insulin extracted from millions of animal pancreases and created the biotech industry; drugs made by living cells are now among the world's best-selling medicines.
How we know
Genentech's 1979 paper in PNAS, the FDA's 1982 approval, Genentech and Lilly records, and drug-sales data in which antibody drugs rank near the top.
Still unknown or debated
US insulin prices rose steeply after about 2000 despite the old technology; patents on improved versions, middlemen and the small number of makers are all blamed.
Connections (3)
▸Insulin was remade by bacteria as Biotech drugs (human insulin)Well documented
The connection
For 60 years insulin was extracted from cattle and pig pancreases. Because it is a small protein whose structure Frederick Sanger had worked out in 1955, it was an ideal first target for genetic engineering. Genentech built synthetic human insulin genes, put them into bacteria, and Eli Lilly sold the result as Humulin from 1982.
When and how
Genentech in South San Francisco and the City of Hope in Duarte, California, August 1978; scaled up by Eli Lilly of Indianapolis and approved in October 1982.
How we know
Genentech's 1979 paper and the FDA's 1982 approval of Humulin, the first drug made with recombinant DNA, document the link directly.
Debates and open questions
Whether human insulin worked better than purified animal insulin is debated; late-1980s complaints that it blunted warning signs of low blood sugar were not confirmed by later studies.
▸Genetic engineering (recombinant DNA) led to Biotech drugs (human insulin)Well documented
The connection
Recombinant DNA let a human gene be inserted into bacteria, which then made the human protein in fermentation tanks. Herbert Boyer, co-inventor of the method, co-founded Genentech in 1976 with venture investor Robert Swanson to turn it into products; the company made the human hormone somatostatin in 1977 and human insulin in 1978.
When and how
South San Francisco, 1976–1982; Genentech's 1980 stock offering, whose share price more than doubled on the first day, launched a wave of biotech investment.
How we know
Boyer's role at Genentech, the Cohen–Boyer patents licensed to hundreds of companies, and FDA drug approvals document the direct path.
Debates and open questions
Whether universities should patent and profit from basic research, as Stanford and the University of California did with the Cohen–Boyer patents, is still debated.
▸Biotech drugs (human insulin) pioneered the protein manufacturing behind GLP-1 drugs (Ozempic, Wegovy)Mostly agreed
The connection
Genentech's 1978 human insulin showed that engineered microbes could manufacture human hormones at scale. Novo Nordisk, the Danish insulin maker, applied the same skills: liraglutide and semaglutide are peptides, short protein chains, made in genetically engineered yeast and then chemically modified to last longer in the blood.
When and how
Genentech in South San Francisco, 1978; Novo Nordisk in Denmark, making yeast-grown insulin from the 1980s; liraglutide approved 2010, semaglutide 2017.
How sure are we?
Regulatory filings describe semaglutide's production by recombinant DNA in yeast, followed by chemical modification.
Debates and open questions
Newer pill candidates such as orforglipron are small chemical molecules, not proteins, so future GLP-1 drugs may not need biotech manufacturing.