There are many drugs that are used “off label” that save lives.

A common strategy for drug companies is to get approval for use on a pathology that is easy to demonstrate effectiveness against when the bigger market exists for another pathology that would take longer to get approval for.

So the maker will go through the approval process while simultaneously sponsoring university studies of the same molecule being used against other pathologies. When shown effective in such studies, many practitioners will go “off label” to use the drug against that other pathology.

This strategy has been vital to the development of oncology drugs that attack tumors by cutting off their blood supply.