DonkeyHody wrote:

Lots of little drug research companies can cook up new cancer drugs in
their laboratories. Only the big drug manufacturers have the
resources to fund the clinical trials necessary to get FDA approval
for a new drug. Sometimes, a new drug will show lots of promise. But
the manufacturer will shelve the drug because it would make their LAST
cancer drug obsolete, and they haven't made enough money from it yet
to recover the cost of getting it to market - unless a competitor is
about to launch a product better than their old one. Meanwhile,
people are dying that could be saved by the new drug. On the one
hand, it looks immoral to put profits ahead of the needs of dying
people. On the other hand, if they couldn't make money, they would go
out of business and no one would be able to fund the studies. Issues
that appear to be black and white seldom are.

In a similar vein, sometimes when researchers are looking for something
like a new cancer drug, they accidentally stumble across something that
shows promise for treating anther, much rarer condition. If the market
for this potential discovery isn't big enough to warrant the R&D
investment, it does not get pursued.