A vial of insulin costs far more in the U.S. than it does in Canada.
Drug prices are set by Canada’s Patented Medicine Prices Review Board which sets price caps by comparing drug prices across a group of 11 countries. The US used to be included in the formula, but was removed from the group in 2022 — because US drug prices are an insane global outlier.
https://en.wikipedia.org/wiki/Patented_Medicine_Prices_Review_Board
A group of Pharma companies including Pfizer and Merck have asked the Trump administration to put pressure on Canada. They are accusing the country of unfair trade practices.
And it was a Republican idea to let Americans buy from Canada.