After these successful projects, Johnson had a reputation as a visionary at Eli Lilly. He was promoted to Vice President of Research, Clowes old position, in 1973.
When Johnson took over the job of Vice President of Research at Eli Lilly, he became aware of a looming crisis. Eli Lilly manufactured most of the insulin sold in the United States. From their detailed sales figures, they knew that the demand for insulin was growing each year.
Genetics is a primary cause of diabetes. When diabetes became a chronic disease in 1920’s with Banting’s discovery of insulin, it enabled people with diabetes to live longer and reproduce more. This led to an ever increasing population with diabetes. In addition, education and better equipment led to more diagnoses of diabetes. Together, the demand for insulin was growing at a steady 3-4% per year. This growth resulted in the demand for insulin doubling every 20 years, or so.
The production of insulin was limited by the amount of pancreases available. By 1977, Johnson and his team at Eli Lilly were predicting a crisis could occur within five years. They had a good idea of how many units of insulin would be required by US patients in 1982, and it was just about equal to all the available pancreases produced by the US meat packing industry.
Eli Lilly could pull a few tricks to increase the supply. About 10% of all pancreases were not being used for insulin, mostly they were sold for consumption as sweetbreads, a delicacy. (There are two types of sweetbreads. One is the thymus and the other is the pancreas. In the early days of insulin, some failed insulin preparations were tracked down to a butcher providing the thymus rather than the pancreas.) Many pancreases were not collected, perhaps 40% of the total. However, these were not collected for a number of reasons: the animal is slaughtered in small abattoirs, making collection inefficient; the animal might be sick and condemned; the animal was not slaughtered in a USDA certified facility.
The supply of pancreases was variable. The supply could be effected by weather, disease, and other factors. If nothing was done, within a decade not enough insulin would be available for all the patients who needed it. Unlike the production of vincristine, where you could just grow more periwinkle plants, one couldn’t just ask ranchers to grow more cattle. In the 1970’s cattle went for about $400/head. A pancreas was only worth $0.75. If you only grew cattle for the pancreas, the price of insulin would have to increase by at least a factor of 100. Eli Lilly was actively searching for alternatives.