It's been around about a century. It's difficult to manufacture a consistent biosimilar insulin. Regulation, physicians and patients all place a high premium on

It's been around about a century. It's difficult to manufacture a consistent biosimilar insulin. Regulation, physicians and patients all place a high premium on consistency and especially avoiding inconsistent doses that cause hypoglycemia. Additionally, the manufacturers, physicians and patients all push to move to new insulins as often as they become available, reducing the demand for generics (which is why, even though Walmart and Costco sell cheap over-the-counter insulin, almost no one uses it.) One interesting project to watch is the partnership between Civica and the state of California to produce quality generic insulin. CA obviously has deeper pockets than Cuban was willing to commit to Cost Plus, so hopefuly the partnership will be more fruitful.