There is a particular flavor of conspiracy theory surrounding disease cures that can be stated like this: private interests actively suppress disease cures because they can make more money by "milking" the diseased through on-going treatments that last a lifetime instead of cures which only earn money until the disease is mostly gone. Historical evidence does not favor this theory, but putting that aside I am interested in the underlying incentive problem.
Suppose it is extremely costly to research and develop a mechanism that totally kills all of the roaches, ants, and termites living in or around your home. Such a panacea insecticide could exist; it would just be very costly to develop it. On the other hand, suppose that common insect repellents are relatively cheap and easy to produce, or at least the chemists consulting with would-be insecticide company founders can give convincing reasons to expect it to be cheap.
Then the forecasted income stream from an on going business that makes the cheaper insecticides is more likely to succeed, more likely to get needed venture capital funding, and more likely to actually produce insect repellents that improve the lives of consumers. The savvy business investor will be incented to make products that solve a problem. Yes, an insect "cure" would be better than an on going insect "treatment" and we could grumble that the evil business investor is diverting funds that could otherwise be exhaustively spent on a cure search. But then in the meantime we might not have the useful stop gap repellents that, while not a cure, sure make life better and are more guaranteed due to their lower production burden.
Why doesn't similar reasoning apply to disease? I sure don't want to get cancer. It looks like a pretty difficult disease to understand and treat, much more so to cure. But smart people have already devoted a lot of time to explore potential cures, most of which haven't shown signs of working. So we should expect a full cure to be very, very difficult and expensive. So should I desire folks to go Indiana Jones style after that cure or praise them if they do? Their highly risky and expensive research efforts may fail to produce the "cancer repellent" equivalent along the way, leaving us with no cure, no treatment, and lost wealth.
Instead, perhaps a pharmaceutical company might look at the business implications of a long term revenue stream from on going cancer treatments... the better the treatment (less pain, no hair loss, less weakness or morbidity) the more money people will pay for the treatment stream. That sounds like a good world for future me to live in. Yes, I'd like a flat out cure more than that, but if the incentives can more reliably steer people towards a treatment that also improves my life, I'll happily take it.
To summarize, on going cancer treatments may very well be "better" than cancer cures, in the sense that treatments could be more cheaply and reliably achieved and actually offer investors an attractive revenue stream that will act as an incentive to get them to solve the problem. Going for the cure only, and sneering at treatments as if they are "greedy" ways to solve the problem is disingenuous: if it improves lives reliably then it's a good thing even if it's not the hard-to-get best thing.
I suspect some folks will not like this and will see it as "giving up" on a cure when, because of the high value of human life, we should practically give up anything to find a bullet proof cure. Economic behavior suggests that people only pay lip service to such an idea. But if you're more committed to your convictions than most, an excellent avenue to explore is prize-based charity so that you actively incent people to win a prize for single milestones of achievement. If it's true that people really want expensive cancer cures instead of just the cheaper cancer repellent, we ought to see a lot more private prize donations.