Whenever the spotlight falls on an expensive drug, some policymakers will point to drug re-importation as a potential solution: If a drug is too expensive here, let patients import them from Canada, where drug prices are much lower.

In America, importation can be the last resort for patients burdened by high drug prices. But in countries around the world, it may be the only way a patient can access lifesaving drugs that have not been cleared for use, or whose government-run health system may simply refuse to cover.