system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5 Why is market competition not driving down the prices of insulin in the US?
gpt
Many of the common modern insulin analogues are sometimes still under patent or only recently have had interchangable biosimilar products approved (also, getting an approval for a biosimilar also takes a very long time).

When a company has the legal right to be the only supplier of a particular specific good, even if mildly similar alternatives exist, that company can set their own prices without much restriction.