This is a place where billionaires and philanthropists could make a huge difference, if they had the will.
It’s definitely a problem that once something is off-patent and/or no longer exclusive, it becomes essentially worthless to investigate it further.
Interesting news item from November of last year:
Old laboratory mice develop substantially fewer and less-aggressive lung tumors than younger animals in a new study led by Stanford University researchers. The discovery flies in the face of established dogma that holds that cancer risk increases with age, but it dovetails with what’s seen in very elderly people, in whom cancer risk appears to either level off or even decline with age.
However, maybe very old mice die from other kinds of cancer at a faster rate. So, depending on the age of the mouse, different types of interventions might be needed to reduce the chance they get cancer – one intervention might work best when the mouse is middle-age, but utterly fail to prevent cancer in old age.