For less common diseases, sometimes all medications are off-label, because the market is small enough that nobody will fund studies to get a new indication appr

For less common diseases, sometimes all medications are off-label, because the market is small enough that nobody will fund studies to get a new indication approved. There are approximately 100,000 human diseases known to science. Who is going to pay for new approvals (costing tens of millions each) for every single one? Should every patient with one of these diseases be yanked off their existing medication indefinitely, even if it works for them?